Force Feedback Citation List March, 1995 1 AN 16644930 AU Agba-Emmanuel-I. TI SeaMaster: an ROV-manipulator system simulator. (remotely operated vehicle). SO IEEE-Computer-Graphics-and-Applications. Jan, 1995. v15(n1). p24(8). IL chart. photograph. program. AB SeaMaster is a remotely operated vehicle (ROV)-manipulator system simulator which can be used both as an individual operator training system and along with the ROV-manipulator system to rehearse and automate jobs. It offers three control modes and its object interference detection strategy allows collisions to be forecasted, objects to be moved, force-feedback to be displayed as color changes and paths to be computed automatically. It has been used in operator training and rehearsal, and there is a scope for further improvements. 2 AN 16348646 AU Colgate-JE. TI Coupled stability of multiport systems - theory and experiments. SO Journal-of-Dynamic-Systems-Measurement-and-Control. Sept, 1994. v116(n3). p419(10). IL chart. graph. photograph. AB This paper presents both theoretical and experimental studies of the stability of dynamic interaction between a feedback controlled manipulator and a passive environment. Necessary and sufficient conditions for 'coupled stabili ty' - the stability of a linear, time-invariant n-port (e.g., a robot, lineariz ed about an operating point) coupled to a passive, but otherwise arbitrary, environment - are presented. The problem of assessing coupled stabili ty for a physical system (continuous time) with a discrete time controller is then addressed. It is demonstrated that such a system may exhibit the coup led stability property; however, analytical, or even inexpensive numerica l conditions are difficult to obtain. Therefore, an approximate conditi on, based on easily computed multivariable Nyquist plots, is developed. T his condition is used to analyze two controllers implemented on a two-lin k, direct drive robot. An impedance controller demonstrates that a feedb ack controlled manipulator may satisfy the coupled stability property. A LQG/LTR controller illustrates specific consequences of failure to meet the c oupled stability criterion; it also illustrates how coupled instability may arise in the absence of force feedback. Two experimental procedures - measurem ent of endpoint admittance and interaction with springs and masses - are int roduced and used to evaluate the above controllers. Theoretical and experimen tal results are compared. CP COPYRIGHT American Society of Mechanical Engineers 1994 3 AN 16118276 AU Jeng-One-Jang. Radwin-Robert-G. Rodriquez-Arthur-A. TI Functional psychomotor deficits associated with carpal tunnel syndrome. SO Ergonomics. June, 1994. v37(n6). p1055(15). IL chart. graph. table. AB Functional impairments caused by carpal tunnel syndrome (CTS) were examined by a quick pinch and release psychomotor task study. A strain gauge dynamometer was used to observe the psychomotor task performed by the median nerve activated muscles of the hand and the limited force feedback was analyzed. A comparative study of CTS afflicted subjects and those free from any hand afflictions was performed. The influential factors such as force level, inter subject variability hand dominance, learning and test retest reliability were analyzed. 4 AN 16075896 AU Liang-SY. Perry-SA. TI In-process compensation for milling cutter runout via chip load manipulation. SO Journal-of-Engineering-for-Industry. May, 1994. v116(n2). p153(8). IL chart. graph. AB This paper discusses a real-time chip load compensation methodology f or the elimination of cutting force oscillation and machined surface scallop ing due to cutter runout so as to gain better utilization of machine tools. T he concept and implementation of the methodology is illustrated using en d milling as a process of example. In this work a force feedback system was discussed in the angle domain based upon a proportional-integral cont rol strategy and a repetitive learning control strategy to actively manip ulate the chip load during end milling. Numerical simulations based on experimentally identified machining dynamics were presented to compar e the performance of the two control schemes. Experimental investigation un der various cutting conditions was performed to assess the viability of t he feedback compensation system in the context of cutting force response as well as machined surface finish. It has been shown that a proportional-int egral control has limited effectiveness in eliminating the runout-induced c utting force oscillation due to the constraints of system stability and dyna mic performance. On the other hand, the learning control system based on the internal model principal successfully yields a cutting force free of oscillatory components at the spindle frequency and significantly imp roves the quality of machined surfaces by cancelling the nonasymptotically stable dynamics of cutter runout. CP COPYRIGHT American Society of Mechanical Engineers 1994 5 AN 16088736 AU Massimino-Michael-J. Sheridan-Thomas-B. TI Teleoperator performance with varying force and visual feedback. SO Human-Factors. March, 1994. v36(n1). p145(13). IL chart. graph. AB An experimental study was conducted to determine the effects of vario us forms of visual and force feedback on human performance for several 'peg-in-hole'-type telemanipulation tasks. Each of six human test sub jects used a master/slave manipulator during two experimental sessions. In one session the subjects performed the tasks with direct vision, where su btended visual angle, force feedback, task difficulty, and the interaction of subtended visual angle and force feedback made significant difference s in task completion times. During the other session the tasks were perfor med using a video monitor for visual feedback, and video frame rate, forc e feedback, task difficulty, and the interaction of frame rate and forc e feedback were found to make significant differences in task times. An analysis between the direct and video viewing environments showed tha t apart from subtended visual angle and reduced frame rate, the video medium itself did not significantly affect task times relative to direct viewing. CP COPYRIGHT Human Factors Society Inc. 1994 6 AN 15383907 AU Youcef-Toumi-K. Gutz-DA. TI Impact and force control: modeling and experiments. SO Journal-of-Dynamic-Systems-Measurement-and-Control. March, 1994. v116(n1). p89(10). IL photograph. table. chart. graph. AB Robot manipulators and drive systems can experience instability or po or control performance after impacting with an environment. This paper p resents an analytical model for impact which is experimentally validated step-by-step. Extensive simulations and experiments are conducted to explain impact phenomena for the case of a force feedback control of a drive system. The results are based on an energy method and presented concisely in dimensionless form. To this end, a small number of dimensionless grou ps are used to characterize the impact behavior through simulations and test s. The study shows that an integral force compensation with a velocity feedb ack improves force tracking and reject impacts. It is also revealed that impact response can be tuned by selecting a favorable dimensionless ratio of force to approach velocity. CP COPYRIGHT American Society of Mechanical Engineers 1994 7 AN 15056062 AU Kahaner-David. TI Japanese activities in virtual reality. SO IEEE-Computer-Graphics-and-Applications. Jan, 1994. v14(n1). p75(4). IL photograph. AB Japanese companies, universities and government-sponsored research groups are engaged in about 20 major virtual reality (VR) research projects and as many as 80 small VR studies. Matsushita plans to release three products in spring 1994 that will bring VR technology to kitchen remodeling, massage and exercise cycling. Nippon Electric Co is developing hand agents that can grip and move onscreen images. The Kyoto Systems Research Laboratory is working on a natural interface that recognizes facial expressions and hand gestures for input. Researchers at Fujita are involved in building remote-control VR systems for construction robots. The Institute of Engineering Mathematics at the University of Tsukuba and the Product Science Research Institute have experimented separately with force feedback systems to convey VR sensory data to users. Designers at the Tokyo Institute of Technology has developed a finger-ring-based VR system. 8 AN 15056024 AU Encarnacao-Jose. Gobel-Martin. Rosenblum-Lawrence. TI European activities in virtual reality. SO IEEE-Computer-Graphics-and-Applications. Jan, 1994. v14(n1). p66(9). IL photograph. AB European businesses and nonprofit agencies in nearly every country on the continent are conducting research and development of virtual reality (VR) technology. In Germany, the Fraunhofer Institute for Computer Graphics has developed a Virtual Design toolkit for architectural, design and historical applications. UK companies Division Ltd and Advanced Robotics Research Ltd have provided, respectively, VR accelerator boards and workstations, and remote peripherals for robotics use. Another UK company, Virtuality Entertainment Systems, has made advances in VR games, including functions that allow players to integrate characteristics from virtual beings, such as voice. A number of VR demonstration centers have been set up in Germany. Projects in other countries are working on development of force feedback gloves, which use pneumatic pockets or small motors to send sensory input to users. 9 AN 15102789 AU Sukhan-Lee. Hahk-Sung-Lee. TI Modeling, design, and evaluation of advanced teleoperator control systems with short time delay. (Technical). SO IEEE-Transactions-on-Robotics-and-Automation. Oct, 1993. v9(n5). p607(17). IL chart. graph. table. AB A novel real-time teleoperator control system is designed and evaluated to achieve desired performance and robustness under shared compliance control and short time delays of up to a few seconds. For the design, the following are emphasized: 1: Telemonitoring force feedback is introduced as a new form of kinesthetic coupling. 2: Dynamic characteristics of the master and slave arms are actively modified based on generalized impedance control according to local design criteria. 3: The human dynamics involved in generating a control command based on visual and force stimuli are incorporated into the controller design. 4: To balance the robustness/performance trade-off, system performance is optimized subject to a known maximum time delay. The proposed teleoperator control system is simulated with modeled human dynamics in the control loop and compared with a number of conventional methods for evaluation. Simulation results suggest that the proposed control system is superior to conventional systems in terms of performance and robustness under short time delays and human control errors. Finally, experimental evidence is presented that supports the advantages of the proposed telemonitoring force feedback, and describe an experimental method for further validating the human dynamic model of teleoperation. (Reprinted by permission of the publisher.) PT Technical 10 AN 14619284 AU Wang-Danwei. McClamroch-N-Harris. TI Position and force control for constrained manipulator motion: Lyapunov's direct method. (Technical). SO IEEE-Transactions-on-Robotics-and-Automation. June, 1993. v9(n3). p308(6). AB The use of robot manipulators frequently requires the control of the position and velocity of the end-effector and the constraint force between the end-effector and the environment. A modified computed torque controller for achieving stable position and force tracking is described. Lyapunov's direct method is utilized to develop position and force control laws for constrained manipulators. The method eliminates problems related to nonlinearities of the robot dynamics and the coupling between them and the holonomic constraints. A class of position and force feedback controllers is developed. Force feedback is found to be useful in improving specific closed loop robustness properties, but is not mandatory for closed loop stabilization. PT Technical 11 AN 14001100 AU Lumelsky-Vladimir-J. Cheung-Edward. TI Real-time collision avoidance in teleoperated whole-sensitive robot arm manipulators. SO IEEE-Transactions-on-Systems-Man-and-Cybernetics. Jan-Feb, 1993. v23(n1). p194(10). IL photograph. chart. AB In traditional teleoperation systems, the human operator is saddled with two distinct tasks: 1) moving the robot arm to its desired position, and 2) avoiding obstacles that can obstruct the arm motion. The current robot teleoperation research concentrates on providing the operator with as much input information about the task site as possible using, for example, stereo vision or contact force feedback. These methods presume that the operator is capable of planning motion for the entire body of the robot in a cluttered environment. Studies show, however, that the operators, first, cannot address both tasks in real time, and second, are not good at generating collision-free motion in a complex environment. Recent results in sensor-based motion planning suggest that the collision avoidance task can be handled automatically, thus freeing the operator for global control. To this end, it is also proposed to use whole-sensitive arm manipulators whose whole bodies are covered with a sensitive skin sensor to detect nearby objects. The data from the skin is processed by motion planning algorithms, to avoid collisions for the entire arm body in an unknown or time-varying environment. The motion of the operator-controlled master arm is either repeated faithfully by the slave arm, or, to avoid collisions, is used as general guidance. In the latter case the slave arm attempts to be as close as possible to the positions commanded by the operator, without jeopardizing its safety. The result is an efficient, safe and robust hybrid system in which integration of control by the operator and the automatic system is done transparently and in real time. CP COPYRIGHT Institute of Electrical and Electronics Engineers Inc. 1993 12 AN 13690544 AU Brienza-David-M. Inigo-Rafael-M. Chung-Kao-Chi. Brubaker-Clifford-E. TI Seat support surface optimization using force feedback. SO IEEE-Transactions-on-Biomedical-Engineering. Jan, 1993. v40(n1). p95(10). IL table. chart. graph. AB The development, implementation and evaluation of an algorithm designed to find optimal seat support surfaces is presented. The algorithm has been developed and implemented on an active contour measurement device. The device consists of an array of positioning elements equipped with force sensors for feedback. With a patient seated on the array, the algorithm is designed to find a seat contour that optimally satisfies given performance criteria. The performance criteria are based on measured stiffness of the soft tissues. A theoretical development of the algorithm is presented along with the modifications made to the algorithm during implementation. The results from several tests using man-made test bodies and a prototype contour gage are presented to verify the algorithm's performance. CP COPYRIGHT Institute of Electrical and Electronics Engineers Inc. 1993 13 AN 14168244 AU Biocca-Frank. TI Virtual reality technology: a tutorial. (Virtual Reality: A Communication Perspective). SO Journal-of-Communication. Autumn, 1992. v42(n4). p23(50). IL photograph. chart. table. AB The elements of virtual reality technology or the media in which virtual reality is created and transmitted is presented. The media is an immersive system that has developmental logic. They must create a sense of presence. The hardware of such technology include head-mounted displays using graphic software and high density resolution. Alternative display units include direct retinal write displays using low-powered lasers, aural display units, tactile displays making use of haptic units, electrotactile and vibrotactile devices as well as force feedback devices. Other equipment include exoskeletons, data gloves, olfactory devices and data suits. Central to all systems is the graphic computer. 14 AN 13411489 AU Patton-R. Swern-F. Tricamo-S. van-der-Veen-A. TI Automated cloth handling using adaptive force feedback. SO Journal-of-Dynamic-Systems-Measurement-and-Control. Dec, 1992. v114(n4). p731(3). IL chart. AB In this paper, a control loop for the handling of cloth is described and tested. The control loop is an adaptive force feedback controller which both provides correct tension on the cloth and straightens wrinkles in the cloth. The control loop was implemented and tested on a PUMA 560 robot with a LORD 15/50 force/torque sensor mounted on its wrist. Experiments demonstrate the ability of the control loop to straighten the cloth and to exert a specified tension on the cloth. CP COPYRIGHT American Society of Mechanical Engineers 1992 15 AN 12804113 AU Shandle-Jack. TI Virtual reality needs better sensors. (Technology Briefing) (Column). SO Electronic-Design. Sept 17, 1992. v40(n19). p18(1). AB Virtual reality (VR) is providing fertile ground for engineers. VR still needs an optimum position-sensing technology that uses data from head-mounted position sensors to locate a participant within the x, y, and z axes of virtual space. Current products that deliver accuracy are still too expensive for business or consumer applications. The tactile sensing and force feedback areas of VR also present a variety of opportunities. Better systems for interacting with the virtual world are needed. Improved tactile sensing in gloves are needed; micromachined devices could be the answer. Force-feedback devices are needed that can simulate real objects. VR needs real sensor technology to move beyond the most expensive applications. PT Column 16 AN 12583281 AU Churbuck-David-C. TI Applied reality. (virtual reality becomes an industrial tool) (Computers/Communications). SO Forbes. Sept 14, 1992. v150(n6). p486(4). AB Virtual reality is coming of age in the industrial world as companies, such as VPL Inc, Bechtel and Boeing, design systems for factory controls, experimental aircrafts and construction equipment, among others. Research and experimentation, however, continues in the aspect of tactile control - an area in which virtual reality technology is deficient. A basic virtual reality system manipulates abstract objects via a disembodied hand that floats in space. The movements are then translated into commands that can control the visual display. For more complex applications such as surgery, however, information that can be had from tactile manipulation is essential for precise maneuvers. Virtual reality researchers are experimenting on various approaches to solve such tactile deficiency. One approach uses tactors, or tiny switches created from a 'shape memory' nickel-titanium alloy, that are sensitive to touch. A force feedback joystick being experimented on can mimic an object's texture. 17 AN 12339165 AU Gosch-John. TI Interactive trackball relies on force-feedback sensing. SO Electronic-Design. May 1, 1992. v40(n9). p32(2). IL photograph. AB Researchers at the Institute for Perception Research in Eindhoven, the Netherlands, have designed an innovative trackball cursor control device that greatly reduces user movement and eyestrain via its ease of use and ability to sense resistive force. Unlike traditional input devices that require hand and arm movement, this new trackball is moved using a single finger. Traditional trackballs allow the cursor to move any where on the screen, causing excessive motion and eyestrain, but the new trackball can be programmed to restrict he cursor's movement. If the cursor strays into inappropriate areas, the user feels resistance and is guided back to approved areas. Eye-hand reaction time is about 30 percent less because the direct movement of the cursor by the trackball makes it easier to locate. 18 AN 12010516 AU Holloway-Richard. TI Virtual worlds research today. (University of North Carolina). SO Byte. April, 1992. v17(n4). p180(1). AB A new system under development at the University of North Carolina (UNC) at Chapel Hill will let users 'walk through' virtual scenes with a three-dimensional interface. It combines VPL Research's EyePhone for displaying images, an optoelectronic tracker for monitoring head position and orientation and a massively parallel graphics engine for generating the images displayed on the head-mounted display. Ivan Sutherland first postulated the development of virtual worlds in 1965, and researchers at NASA-Ames, MIT and the University of North Carolina are among those who have developed new technologies to create 'artificial reality' which the user can directly experience. Major technical problems remain; image generation of complex scenes is still difficult at real-time rates, and force feedback has not yet been perfected. UNC researchers are addressing all of these issues. 1 AN 4898025. AU Sato-T. Ichikawa-J. Mitsuishi-M. Miyazaki-H. Hatamura-Y. IN Res. Center for Adv. Sci. & Technol., Tokyo Univ., Japan. TI Micro-teleoperation with manual task execution posture. SO IEEE Control Systems Magazine. vol.15, no.1. pp. 22-9. Feb. 1995. YR 1995. RN CCCC: 0272-1708/95/$04.00. AB This article describes a new micro-teleoperation system that is inherently suitable for micro-object handling since it mitigates several drawbacks associated with human interface devices. The system uses an upward-facing CRT display monitor mounted beneath a table. An operator performs micro-tasks in a sitting posture at the table while looking down at the monitor with a touch sensor screen situated between the operator's arms. To execute these tasks, microscope-observed images of the target objects are utilized in conjunction with the touch sensor screen and a specially designed, pencil-shaped master manipulator having a force-feedback function. The system incorporates the following characteristic features: (1) intuitive teleoperation is possible because coincidence of the operating and monitoring point is provided, (2) the pencil-shaped master manipulator enables sensitive bilateral micro-teleoperation because of its light weight and small inertia for movement, and (3) with the side of the right hand fixed in a pen-holder grip, the operator uses the master manipulator to generate commands with a wide dynamic range of force feedback, i.e., the operator can simultaneously feel force feedback during operation from both pressure/slip sensory receptors on the fingertips and sensory receptors which detects stretching of the finger muscles. The stated features are proved experimentally by the constructed micro-teleoperation prototype system. 2 AN 4895917. AU Massimino-M-J. IN McDonnell Douglas Aerosp., Houston, TX, USA. TI Improved force perception through sensory substitution. SO Control Engineering Practice. vol.3, no.2. pp. 215-22. Feb. 1995. YR 1995. RN CCCC: 0967-0661/95/$9.50+0.00. AB The objective of the research presented in this paper was to study the capabilities of sensory substitution for force feedback, presented to the operator of a teleoperation system, through the tactile and auditory senses. Traditional bilateral force feedback or force reflection, which applies forces to a human operator's hand or arm muscles, while generally beneficial can be limited in the operator's ability to perceive small force values. Sensory substitution for force feedback was shown in this study to increase the operator's ability to perceive small forces by allowing an increase in the effective feedback gain without risking instability or impeding the operator's inputs to the system. 3 AN 4895915. AU Liu-M-H. IN Dept. of Control Eng., Tech. Univ. Darmstadt, Germany. TI Force-controlled fuzzy-logic-based robotic deburring. SO Control Engineering Practice. vol.3, no.2. pp. 189-201. Feb. 1995. YR 1995. RN CCCC: 0967-0661/95/$9.50+0.00. AB In this paper a three-step active deburring strategy is proposed based on fuzzy logic and force feedback control. A strategy for automatic contour following is developed to identify unknown workpiece contours, to automatically generate desired robot motions, and to detect unknown burr sizes and positional inaccuracies. Under the deburring strategy the robot motion and force control are planned actively according to the detected burr sizes and positional inaccuracies. A fuzzy man-machine interface is built to make use of the knowledge of human operators to simplify the burr detection. A fuzzy model of the deburring process is developed to support the planning of deburring procedures. Implementation of and experiments with the proposed strategies are described. 4 AN 4894156. AU Chao-An-Shih. Shui-Shong-Lu. Han-Pang-Huang. IN Dept. of Mech. Eng., Nat. Taiwan Univ., Taipei, Taiwan. TI Robotic deburring with a hybrid-compliance end-effector. SO Journal of the Chinese Institute of Engineers. vol.17, no.4. pp. 499-511. July 1994. YR 1994. AB This paper presents a hybrid-compliance end-effector (HCEE) for the purpose of deburring. It is composed of springs and/or dashpots for passive compliance, and a deburring force feedback using a dc motor for active compliance. A coupled system concept taking the whole tool/workpiece system as integrated is used for the analysis. The system model includes the tool holder dynamics, the motor/controller dynamics and the deburring process. A simple proportional controller is used to provide the HCEE with active compliance. Simulation and experimental results show that the hybrid compliance end-effector design can achieve good performance results in the deburring task. 5 AN 4880743. AU Alter-D-M. Tsu-Chin-Tsao. IN Dept. of Mech. & Ind. Eng., Illinois Univ., Urbana, IL, USA. TI Dynamic stiffness enhancement of direct linear motor feed drives for machining. SO Published by: IEEE. New York, NY, USA. 1994. CT Proceedings of the 1994 American Control Conference (Cat. No.94CH3390-2). Baltimore, MD, USA. pp. 3303-7 vol.3. American Autom. Control Council. US Nat. Member Organization of IFAC. AIAA. AIChE. AISE. ASME. IEEE. ISA. SCS. 29 June-1 July 1994. YR 1994. AB Linear motion electric motors have shown promising potential for use as next generation machine tool feed drives since they can increase machining rates and improve servo accuracy by eliminating gear related mechanical problems. To combat chatter instability, large dynamic stiffness is desirable in the servo control loop. This paper investigates the use of optimal H/sub infinity / control to design for large stiffness. Position feedback alone is first considered, with cutting force feedback later added to augment closed loop stiffness. Optimal position feedback is experimentally seen to achieve up to a 46% stiffness improvement over that achievable with proportional derivative control. The addition of force feedback to the servo loop resulted in a further 70-100% stiffness improvement over the position feedback alone values. 6 AN 4879979. AU Chanezon-A. Takemura-H. Kitamura-Y. Kishino-F. IN ATR Commun. Syst. Res. Lab., Kyoto, Japan. TI A study of an operator assistant for virtual space. SO Published by: IEEE. New York, NY, USA. 1993. CT IEEE Virtual Reality Annual International Symposium (Cat. No.93CH3336-5). Seattle, WA, USA. pp. 492-8. Virtual Reality Technol. Committee IEEE Neural Networks Council. SPIE. IEEE Seattle Sect. IEEE Ind. Electron. Soc. IEEE Inf. Theory Soc. IEEE Laser & Electro Opt. Soc. IEEE Oceanic Eng. Soc. IEEE Robotics & Autom. Soc. IEEE Signal Process. Soc. 18-22 Sept. 1993. YR 1993. RN CCCC: 0 7803 1363 1/93/$3.00. AB A method to assist an operator to place an object on a surface in a virtual environment without any force feed-back tool is described and evaluated. The method used is to apply an attractive power to two faces that are likely to be attached. The system checks the distance of these faces and assists the operator by attaching two faces whose distance is less than a certain threshold. The real time calculation is achieved by limiting the number of faces that can be attached. Using this interface, the operator can move an object in some predefined planes. An experiment shows that the method is effective when the operator is requested to precisely place a virtual object in a certain location. 7 AN 4879957. AU McNeely-W-A. IN Boeing Comput. Services, Seattle, WA, USA. TI Robotic graphics: a new approach to force feedback for virtual reality. SO Published by: IEEE. New York, NY, USA. 1993. CT IEEE Virtual Reality Annual International Symposium (Cat. No.93CH3336-5). Seattle, WA, USA. pp. 336-41. Virtual Reality Technol. Committee IEEE Neural Networks Council. SPIE. IEEE Seattle Sect. IEEE Ind. Electron. Soc. IEEE Inf. Theory Soc. IEEE Laser & Electro Opt. Soc. IEEE Oceanic Eng. Soc. IEEE Robotics & Autom. Soc. IEEE Signal Process. Soc. 18-22 Sept. 1993. YR 1993. RN CCCC: 0 7803 1363 1/93/$3.00. AB A new conceptual solution is presented for the problem of providing force feedback for virtual reality, concentrating on potential CAD/CAM applications. The essential concept is that force feedback is provided by interactions between the human operator and specialized external (as opposed to worn) robots. This is called "robotic graphics" to express the analogy between robots simulating the feel of an object, and graphics displays simulating its appearance. This is illustrated by introducing the derivative concepts of "robotic shape displays" and "roboxels.". 8 AN 4879956. AU Ishii-M. Sato-M. IN Precision & Intelligence Lab., Tokyo Inst. of Technol., Midoriku, Yokohama, Japan. TI A 3D interface device with force feedback: a virtual work space for pick-and-place tasks. SO Published by: IEEE. New York, NY, USA. 1993. CT IEEE Virtual Reality Annual International Symposium (Cat. No.93CH3336-5). Seattle, WA, USA. pp. 331-5. Virtual Reality Technol. Committee IEEE Neural Networks Council. SPIE. IEEE Seattle Sect. IEEE Ind. Electron. Soc. IEEE Inf. Theory Soc. IEEE Laser & Electro Opt. Soc. IEEE Oceanic Eng. Soc. IEEE Robotics & Autom. Soc. IEEE Signal Process. Soc. 18-22 Sept. 1993. YR 1993. RN CCCC: 0 7803 1363 1/93/$3.00. AB The construction of the virtual work space for pick-and-place tasks with a new 3D interface device named SPIDAR II is discussed. The device can measure the motions of the thumb and the forefinger, and can provide the force sensations to the thumb and the forefinger. The operator can manipulate the virtual objects directly in the virtual work space using the device. The pick-and-place tasks are performed in the virtual space. The effects of the force sensations which are provided by the device are estimated. The results indicate that the appropriate forces are important for the pick-and-place task. The virtual block gives the best performance of pick-and-place tasks in virtual work space. 9 AN 4879950. AU Bostrom-M. Singh-S-K. Wiley-C-W. IN Thayer Sch. of Eng., Dartmouth Coll., Hanover, NH, USA. TI Design of an interactive lumbar puncture simulator with tactile feedback. SO Published by: IEEE. New York, NY, USA. 1993. CT IEEE Virtual Reality Annual International Symposium (Cat. No.93CH3336-5). Seattle, WA, USA. pp. 280-6. Virtual Reality Technol. Committee IEEE Neural Networks Council. SPIE. IEEE Seattle Sect. IEEE Ind. Electron. Soc. IEEE Inf. Theory Soc. IEEE Laser & Electro Opt. Soc. IEEE Oceanic Eng. Soc. IEEE Robotics & Autom. Soc. IEEE Signal Process. Soc. 18-22 Sept. 1993. YR 1993. RN CCCC: 0 7803 1363 1/93/$3.00. AB A computer-based simulation utilizing high-resolution 3D graphics and a force-feedback device to train students and/or residents in limiter puncture is discussed. The simulator consists of a combination of specialized hardware, custom software running on a high-resolution graphics workstation. The hardware under development for this project is described. The major piece of specialized hardware is the force-feedback needle simulator. Position sensors track the insertion angle or trajectory of the device, while a programmable motor or actuator provides variable resistance to insertion, depending upon which simulated anatomic structures the virtual needle is penetrating. Thus, the student may place the virtual needle at the desired angle and will feel realistic resistance while inserting. If an incorrect trajectory is used and bone is contacted, the resulting sudden sharp increase in resistance would be conveyed. 10 AN 4879948. AU Shimoga-K-B. IN Robotics Inst., Carnegie Mellon Univ., Pittsburgh, PA, USA. TI A survey of perceptual feedback issues in dexterous telemanipulation. I. Finger force feedback. SO Published by: IEEE. New York, NY, USA. 1993. CT IEEE Virtual Reality Annual International Symposium (Cat. No.93CH3336-5). Seattle, WA, USA. pp. 263-70. Virtual Reality Technol. Committee IEEE Neural Networks Council. SPIE. IEEE Seattle Sect. IEEE Ind. Electron. Soc. IEEE Inf. Theory Soc. IEEE Laser & Electro Opt. Soc. IEEE Oceanic Eng. Soc. IEEE Robotics & Autom. Soc. IEEE Signal Process. Soc. 18-22 Sept. 1993. YR 1993. RN CCCC: 0 7803 1363 1/93/$3.00. AB Some specific requirements on the design of dexterous master devices meant for teleoperating multifingered robotic hands, within the context of finger force feedback, are identified and analyzed. The requirements are of two categories, i.e., constructional and functional. The constructional issues consist of the isomorphism, portability, motion range capability, and accommodation for human hand size variability. The functional issues consist of bandwidth compatibility with the human hand (which itself has asymmetric input/output characteristics), proprioceptive (force limit) compatibility, and consideration of the psychometric stability of the human hand in sensing force magnitudes and variations. Also of importance is the sensitivity of the master device that must be more than that of the human hand. In this regard, 14 existing designs of hand masters are evaluated to see how well they satisfy the stated constructional and functional requirements. 11 AN 4879947. AU Hirota-K. Hirose-M. IN Dept. of Mechano-Inf., Toyko Univ., Japan. TI Development of surface display. SO Published by: IEEE. New York, NY, USA. 1993. CT IEEE Virtual Reality Annual International Symposium (Cat. No.93CH3336-5). Seattle, WA, USA. pp. 256-62. Virtual Reality Technol. Committee IEEE Neural Networks Council. SPIE. IEEE Seattle Sect. IEEE Ind. Electron. Soc. IEEE Inf. Theory Soc. IEEE Laser & Electro Opt. Soc. IEEE Oceanic Eng. Soc. IEEE Robotics & Autom. Soc. IEEE Signal Process. Soc. 18-22 Sept. 1993. YR 1993. RN CCCC: 0 7803 1363 1/93/$3.00. AB As a methodology to develop a force feedback system, the concept of "surface displaying" is introduced. A prototype mechanism and its control system is then designed and developed. Methodology for model calculation and simulation is discussed. The idea of texture mapping in a tactile sense is suggested, and is proven to be effective. 12 AN 4879942. AU Hashimoto-H. Kunii-Y. Buss-M. Harashima-F. IN Inst. of Ind. Sci., Tokyo Univ., Japan. TI Dynamic force simulator for force feedback human-machine interaction. SO Published by: IEEE. New York, NY, USA. 1993. CT IEEE Virtual Reality Annual International Symposium (Cat. No.93CH3336-5). Seattle, WA, USA. pp. 209-15. Virtual Reality Technol. Committee IEEE Neural Networks Council. SPIE. IEEE Seattle Sect. IEEE Ind. Electron. Soc. IEEE Inf. Theory Soc. IEEE Laser & Electro Opt. Soc. IEEE Oceanic Eng. Soc. IEEE Robotics & Autom. Soc. IEEE Signal Process. Soc. 18-22 Sept. 1993. YR 1993. RN CCCC: 0 7803 1363 1/93/$3.00. AB A dynamic force simulator (DFS) for force feedback in human-machine systems is proposed. The DFS simulates object dynamics contact model and friction characteristics of the human hand interacting with objects in a virtual reality environment. After derivation of kinematic and force relations between hand and object space, a method is proposed for calculation and feedback of appropriate forces to the force controlled actuators of the sensor glove which has been developed. 13 AN 4879940. AU Eberhardt-S-P. Bernstein-L-E. Coulter-D-C. Hunckler-L-A. IN Dept. of Eng., Swarthmore Coll., PA, USA. TI OMAR a haptic display for speech perception by deaf and deaf-blind individuals. SO Published by: IEEE. New York, NY, USA. 1993. CT IEEE Virtual Reality Annual International Symposium (Cat. No.93CH3336-5). Seattle, WA, USA. pp. 195-201. Virtual Reality Technol. Committee IEEE Neural Networks Council. SPIE. IEEE Seattle Sect. IEEE Ind. Electron. Soc. IEEE Inf. Theory Soc. IEEE Laser & Electro Opt. Soc. IEEE Oceanic Eng. Soc. IEEE Robotics & Autom. Soc. IEEE Signal Process. Soc. 18-22 Sept. 1993. YR 1993. RN CCCC: 0 7803 1363 1/93/$3.00. AB A system for haptic (i.e. kinesthetic and cutaneous) stimulation of the hand is described. While the immediate application involves display of speech information, a number of other man-machine interface applications may be feasible, including force-feedback devices for computer interaction and human pattern extraction from multiple datastreams. In an attempt to model more closely the information streams available via the Tadoma method, OMAR was developed to stimulate kinesthetic as well as tactile receptors, by moving and vibrating fingers in one or two dimensions using hard-disk head-positioning actuators. OMAR is being used in experiments involving basic haptic perception and supplementation of speechreading with haptic codings of speech correlates obtained via X-ray microbeam measurements. 14 AN 4872915. AU Stewart-A-M. IN Dept. of Appl. Math., Australian Nat. Univ., Canberra, ACT, Australia. TI The use of piezoelectric bimorphs to measure forces in colloidal systems. SO Measurement Science & Technology. vol.6, no.1. pp. 114-23. Jan. 1995. YR 1995. RN CCCC: 0957-0233/95/010114+10$19.50. AB An analysis is made of the effect of errors introduced by bimorph drift and decay upon measurements of colloidal forces made with piezoelectric bimorphs. For direct measurements the errors will be small provided that the time constant of the bimorph, given by the product of its capacitance and amplifier input impedance, is much larger than the total time of measurement. With the force-feedback technique the errors will be negligible provided that, in addition, the integrator time constant is much smaller than the bimorph time constant, which condition is easily satisfied. It is important to use an amplifier with a very high input impedance to buffer bimorphs used for this type of measurement. 15 AN 4870971. AU Hadjiloucas-S. Karatzas-L-S. Keating-D-A. Usher-M-J. IN Dept. of Cybern., Reading Univ., UK. TI Optical sensors for plant water relations. SO Proceedings of the SPIE - The International Society for Optical Engineering. vol.2360. pp. 71-4. 1994. CT Tenth International Conference on Optical Fibre Sensors Conference. Glasgow, UK. Univ. Strathclyde. Glasgow Dev. Agency. Scottish Enterprise. et al. 11-13 Oct. 1994. YR 1994. RN CCCC: 0 8194 1699 1/94/$6.00. AB The potential of optical fibres in monitoring water uptake from plants is considered. Applications include an optical potometer that monitors water uptake from individual roots, the detection of xylem cavitation using audio acoustic emissions with an interferometric force feedback microphone, an optical displacement transducer that detects changes in leaf thickness in relation to leaf water potential, and the use of fluorescence to monitor water uptake and translocation. 16 AN 4864558. AU Kanestrom-R-K. Egeland-O. IN Norwegian Inst. of Technol., Trondheim Univ., Norway. TI Impedance-adjusted active strut. SO Published by: IEEE. New York, NY, USA. 1994. CT Proceedings of the 1994 American Control Conference (Cat. No.94CH3390-2). Baltimore, MD, USA. pp. 1462-6 vol.2. American Autom. Control Council. US Nat. Member Organization of IFAC. AIAA. AIChE. AISE. ASME. IEEE. ISA. SCS. 29 June-1 July 1994. YR 1994. AB A set of active strut controllers are developed based on desired impedance descriptions. Closed loop stability is investigated using the theory of passivity, and experimental results on a truss structure with a piezoelectric active strut are provided. The impedance describing a dashpot in series with the unsoftened open loop spring is found to be most attractive. 17 AN 4864233. AU Cadoz-C. IN CNRS, IMAG, Grenoble, France. TI Force feedback in gestural man-machine dialogue-the concept of instrumental communication. SO Published by: EC2. Nanterre, France. 1994. CT Montpellier '94. 3rd International Conference. Interface to Real and Virtual Worlds. Proceedings. Montpellier, France. pp. 119-29. 7-11 Feb. 1994. YR 1994. AB The development of man-machine communication as an issue in computer science is recent. Within this issue, most of the human communication modalities have been exploited. However, the gestural channel, yet rich, has remained aside. We present the communicational properties of the gestural channel and show how it can play a role in man-machine communication. We introduce a new and essential concept: the instrumental communication inspired by the communicational relationship between the instrumentalist musician and his instrument. Generalized to tasks other than the control of sound phenomena, the instrumental communication with the computer completes the triangular diagram of man-machine-environment interaction modes. 18 AN 4864002. AU Pagilla-P. Tomizuka-M. IN Dept. of Mech. Eng., California Univ., Berkeley, CA, USA. TI Hybrid force/motion control of two arms carrying an object. SO Published by: IEEE. New York, NY, USA. 1994. CT Proceedings of the 1994 American Control Conference (Cat. No.94CH3390-2). Baltimore, MD, USA. pp. 195-9 vol.1. American Autom. Control Council. US Nat. Member Organization of IFAC. AIAA. AIChE. AISE. ASME. IEEE. ISA. SCS. 29 June-1 July 1994. YR 1994. AB In this work we develop a hybrid force/motion controller for coordination of two robot arms carrying an object. A closed chain dynamic model is developed which helps in designing the motion controller independent of the force controller. A stable adaptive motion controller and a parameter adaptation law is designed to estimate the unknown parameters. A feedforward plus PI type force controller is developed. Stability analysis is done for both motion and force controller. It is shown that the motion controller is robust to bounded disturbances and the force controller is robust to small delay in force feedback. The theoretical results have been validated by simulations. 19 AN 4861577. AU Takemura-H. Kitamura-Y. Chanezon-A. Kishino-F. IN ATR Commun. Syst. Res. Labs., Kyoto, Japan. TI An operator assistance method for an object placement task in a virtual environment. SO Journal of the Institute of Television Engineers of Japan. vol.48, no.10. pp. 1312-17. Oct. 1994. YR 1994. AB Because virtual reality techniques can be used to provide an intuitive user interface using human spatial perception, they are promising methods for implementing a sophisticated user interface. Limitations in computational power, however, make it difficult to present a perfect virtual environment, and a simple task in a real environment therefore often becomes a skilled operation in a virtual environment. The paper describes a method enabling an operator in a virtual environment to place an object on a surface without any force-feedback tool. When a grabbed object comes to close to another object, it is attached. Experimental results show that the method is efficient in decreasing the time required for object placement when precise placement necessary. 20 AN 4851958. AU Xiao-Jizhong. Zeng-Xiangqiu. Huang-Yalou. Lu-Guizhang. Edited by: Yuan-Baozong. IN Dept. of Autom. Control, East China Inst. of Technol., Nanjing, China. TI Adaptive force control for position-controlled robot manipulators. SO Published by: IEEE. New York, NY, USA. 1993. CT Proceedings TENCON '93. 1993 IEEE Region 10 Conference on 'Computer, Communication, Control and Power Engineering' (Cat. No.93CH3286-2). Beijing, China. pp. 94-8 vol.4. 19-21 Oct. 1993. YR 1993. AB This paper presents an adaptive force control method for robot manipulators based on Popov's hyperstability criterion. As many researchers have found, one of the difficulties of the control problem is that the stability of the robot force control system is sensitive to the changes of the stiffness of the environment on which the force is exerted. To solve the problem, model reference adaptive control theory is used to identify the environment stiffness, and to determine an adaptive force feedback gain corresponding to the contacted environment. The theoretic analysis and experimental results show that this method can realize a stable force control when the environment stiffness changes to a sufficiently large extent. 21 AN 4847138. AU Kunii-Y. Hashimoto-H. IN Dept. of Inf. Sci., Tokyo Univ., Japan. TI Object grasping in virtual environment using dynamic force simulator. SO Published by: IEEE. New York, NY, USA. 1994. CT Proceedings. 3rd IEEE International Workshop on Robot and Human Communication. RO-MAN '94 Nagoya (Cat. No.94TH0679-1). Nagoya, Japan. pp. 261-4. IEEE Ind. Electron. Soc. Soc. Instrum. & Control Eng. Robotics Soc. Japan. Japan Soc. Mech. Eng. IEICE. New Technol. Found. IEEE Robotics & Autom. Soc. IEEE Neural Networks Council. Inst. Electr. Eng. Japan. Inf. Process. Soc. Japan. Japan Psychology Assoc. Japanese Neural Network Soc. Japan Soc. Fuzzy Theory & Syst. 18-20 July 1994. YR 1994. RN CCCC: 0 7803 2002 6/94/$4.00. AB Realizes force feedback with the dynamic force simulator (DFS) that the authors proposed previously. DFS simulates object dynamics, contact model and friction characteristics of human hand interacting object in virtual reality. After derivation of kinematic and force relations between hand and object space the authors realize desired feedback forces to human operator. Interaction with DFS allows the calculation and feedback of appropriate forces to the force controlled actuators of the sensor glove the authors have developed. 22 AN 4847136. AU Hirota-K. Hirose-M. IN Fac. of Eng., Tokyo Univ., Japan. TI Surface display: a force feedback system simulating the surface of an object. SO Published by: IEEE. New York, NY, USA. 1994. CT Proceedings. 3rd IEEE International Workshop on Robot and Human Communication. RO-MAN '94 Nagoya (Cat. No.94TH0679-1). Nagoya, Japan. pp. 251-4. IEEE Ind. Electron. Soc. Soc. Instrum. & Control Eng. Robotics Soc. Japan. Japan Soc. Mech. Eng. IEICE. New Technol. Found. IEEE Robotics & Autom. Soc. IEEE Neural Networks Council. Inst. Electr. Eng. Japan. Inf. Process. Soc. Japan. Japan Psychology Assoc. Japanese Neural Network Soc. Japan Soc. Fuzzy Theory & Syst. 18-20 July 1994. YR 1994. RN CCCC: 0 7803 2002 6/94/$4.00. AB Force feedback is an interface based on the phenomenon of contact. In the implementation of a virtual force feedback environment, the object is defined in a computer and the user is in the real world. Therefore, an interface device is required to transmit touch sensation to the user's finger when he or she touches a virtual object in virtual space. In this paper, methodology to realize force feedback is categorized from this view point, and the idea of "surface display" is presented as a force feedback method in a virtual environment. 23 AN 4847116. AU Yokoi-H. Yamashita-J. Fukui-Y. Shimojo-M. IN Nat. Inst. of Biosci. & Human Technol., Tsukuba, Japan. TI Development of 3D-input device for virtual surface manipulation. SO Published by: IEEE. New York, NY, USA. 1994. CT Proceedings. 3rd IEEE International Workshop on Robot and Human Communication. RO-MAN '94 Nagoya (Cat. No.94TH0679-1). Nagoya, Japan. pp. 134-9. IEEE Ind. Electron. Soc. Soc. Instrum. & Control Eng. Robotics Soc. Japan. Japan Soc. Mech. Eng. IEICE. New Technol. Found. IEEE Robotics & Autom. Soc. IEEE Neural Networks Council. Inst. Electr. Eng. Japan. Inf. Process. Soc. Japan. Japan Psychology Assoc. Japanese Neural Network Soc. Japan Soc. Fuzzy Theory & Syst. 18-20 July 1994. YR 1994. RN CCCC: 0 7803 2002 6/94/$4.00. AB This paper reports the virtual surface manipulation system with force feedback. The developed system is a Cartesian manipulator with stiffness, toughness, and linearity. The proposed manipulator allows the operator spatially manipulates the virtual space with 6DOF, using a force sensor. The control system of the manipulator realizes smooth movement using velocity control. As an application of the system, the deforming operation of virtual surface is shown in an experiment. This paper describes the mechanism and the control method of the manipulator with adaptive damper using network architecture learning through backpropagation technique. 24 AN 4846348. AU Yoshida-K. Yabuta-T. IN Telecommun. Field Syst. R&D Center, NTT Corp., Ibaraki, Japan. TI Design and evaluation of a bilateral master-slave hand system. SO Published by: IEEE. New York, NY, USA. 1993. CT Proceedings 2nd IEEE International Workshop on Robot and Human Communication (Cat. No.93TH0577-7). Tokyo, Japan. pp. 402-7. IEEE Ind. Electron. Soc. Soc. Instrum. & Control Eng. Robotics Soc. Japan. Japan Soc. Mech. Eng. Inst. Electron. Information & Commun. Eng. New Technol. Foundation. 3-5 Nov. 1993. YR 1993. RN CCCC: 0 7803 1407 7/93/$3.00. AB A prototype bilateral master-slave hand system has been developed. Both the master and slave hands consist of three robot fingers using 3 degree-of-freedom (DOF) small manipulators each equipped with 3-axis force sensor to enable force feedback to the operator. In this paper, the master-slave hand system is described, and the system performance is evaluated based on the concept of the two-terminal pair network. Simulation results are reported which show that this master-slave hand system, using a bilateral control algorithm which was proposed previously, can realize almost ideal response in the low-frequency domain. 25 AN 4846313. AU Kuni-Y. Buss-M. Hashimoto-H. IN Fac. of Sci. & Eng., Cheo Univ., Japan. TI Force flow between human and object in virtual world. SO Published by: IEEE. New York, NY, USA. 1993. CT Proceedings 2nd IEEE International Workshop on Robot and Human Communication (Cat. No.93TH0577-7). Tokyo, Japan. pp. 216-19. IEEE Ind. Electron. Soc. Soc. Instrum. & Control Eng. Robotics Soc. Japan. Japan Soc. Mech. Eng. Inst. Electron. Information & Commun. Eng. New Technol. Foundation. 3-5 Nov. 1993. YR 1993. RN CCCC: 0 7803 1407 7/93/$3.00. AB In this paper we propose a dynamic force simulator (DFS) for force feedback in human-machine systems. The DFS simulates object dynamics, contact model and friction characteristics of the human hand interacting with objects in a virtual reality and aims at the human skill acquisition as a first step of the previously proposed intelligent assisting system (IAS). After derivation of the kinematic and force relations between hand and object space we propose a method of realizing desired feedback forces to the human operator. Interaction with the DFS allows the calculation and feedback of appropriate forces to the force controlled actuators of the sensor glove we have developed. 26 AN 4846302. AU Singh-S-K. Bostrom-M. Popa-D-O. Wiley-C-W. IN Thayer Sch. of Eng., Dartmouth Coll., Hanover, NH, USA. TI Design of an interactive lumbar puncture simulator with tactile feedback. SO Published by: IEEE. New York, NY, USA. 1993. CT Proceedings 2nd IEEE International Workshop on Robot and Human Communication (Cat. No.93TH0577-7). Tokyo, Japan. pp. 156-9. IEEE Ind. Electron. Soc. Soc. Instrum. & Control Eng. Robotics Soc. Japan. Japan Soc. Mech. Eng. Inst. Electron. Information & Commun. Eng. New Technol. Foundation. 3-5 Nov. 1993. YR 1993. RN CCCC: 0 7803 1407 7/93/$3.00. AB Lumbar puncture for purposes of administering spinal or epidural anesthesia is a complex clinical skill which requires the clinician to precisely correlate a detailed mental map of hidden three-dimensional anatomy with tactile feedback from the spinal needle as it is inserted. To be successful the trainee must create a mental map of the anatomy by integrating atlas illustrations with bony and/or surface landmarks. The placement of the needle must then be guided by the continuous correlation of this mental map and the tactile feedback, or "feel," of the needle as it is being inserted. The simulator consists of a combination of specialized hardware and custom software running on a high-resolution graphics workstation. The major piece of specialized hardware is the force-feedback needle simulator. This is a specialized joystick which resembles a long, thin pen or wand swivel-mounted to a vertical face of a box roughly 12 inches on a side. Position sensors track the insertion angle or trajectory of the device while a programmable motor or actuator will provide variable resistance to insertion depending upon which simulated anatomic structures the virtual needle is penetrating. If an incorrect trajectory is used and bone is contacted the resulting sudden sharp increase in resistance would be conveyed. 27 AN 4841990. AU Ichinohe-M. Ohara-K. Yamaguchi-K. Maeda-K. IN Production Eng. Promotion Center, Hitachi Ltd., Tokyo, Japan. TI Deburring robot system for cast iron. SO Robot. no.100. pp. 83-7. Sept. 1994. YR 1994. AB Deburring operation is dusty and noisy, so automation of deburring is strongly required. To solve this problem, robot system which has vision sensing, automatic robot program generation, and force feedback control function is developed. The sequence of this system is as follows, at first, real work size and burr size of each work are measured by vision sensing. Next, automatic robot program generator calculates the optimum deburring condition (contact force, feed speed, etc.) which suits to the measured burr size, and generates the robot program. Then, robot deburrs according to this program. When robot is deburring, contact force is controlled to decided value by force feedback control. This system accomplishes high quality finishing surface, by generating robot program which includes optimum deburring condition to each work. 28 AN 4829413. AU Wen-Yeuan-Chung. Waldron-K-J. IN Dept. of Mech. Eng., Ohio State Univ., Columbus, OH, USA. TI Simulations of dexterous manipulation for multifingered systems. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1994. CT Proceedings 1994 IEEE International Conference on Robotics and Automation (Cat. No.94CH3375-3). San Diego, CA, USA. pp. 2321-6 vol.3. IEEE Robotics Autom. Soc. 8-13 May 1994. YR 1994. RN CCCC: 1050-4729/94/$03.00. AB Combined grasping and manipulation by multifingered hands was studied. A method of force allocation by optimizing the friction angles at finger contacts was combined with the computed torque method to find the torques to be commanded at finger joints for multifingered systems. In this way, the chance of slip can be minimized when the object is grasped or manipulated. A rolling motion between the grasped object and the fingertips was studied in simulation. A history-based method was proposed to improve the smoothness of the input torque commands, and force feedback was used to compensate for the uncertainty of the system. Any finger which moved beyond the boundaries of its working volume was also moved to a new position for regrasping. The proposed method can be efficiently used to find the necessary actuator torques, and is applicable for real-time application. Three dimensional simulation results are given in this paper. 29 AN 4829410. AU Hill-J-W. Green-P-S. Jensen-J-F. Gorfu-Y. Shah-A-S. IN SRI Int., Menlo Park, CA, USA. TI Telepresence surgery demonstration system. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1994. CT Proceedings 1994 IEEE International Conference on Robotics and Automation (Cat. No.94CH3375-3). San Diego, CA, USA. pp. 2302-7 vol.3. IEEE Robotics Autom. Soc. 8-13 May 1994. YR 1994. RN CCCC: 1050-4729/94/$03.00. AB Endoscopic surgical methods are replacing open surgery in many procedures, but dexterity and force feedback are not adequate with current tools. To enhance the ability of surgeons to operate endoscopically, we have developed a telepresence system with integrated 3D stereo viewing, a prototype force-reflecting manipulator, and aural feedback. Careful attention was paid to the human factors in the endoscopic surgery setting to make the system natural to use in the hope of eliminating the long training period normally required. The 4-axis (plus gripper) manipulator provides the same degrees of freedom as the laproscopic tools now being used for surgery. The bilateral control system provides for magnified motion and/or force reflection. This approach eliminates the motion reversal, or fulcrum effect, in operating through the abdominal wall. Preliminary dexterity experiments with different force feedback and viewing conditions verify intuitive use and fast learning. 30 AN 4824398. AU Sukhan-Lee. Hahk-Sung-Lee. IN Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA. TI Design of optimal time delayed teleoperator control system. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1994. CT Proceedings 1994 IEEE International Conference on Robotics and Automation (Cat. No.94CH3375-3). San Diego, CA, USA. pp. 3252-8 vol.4. IEEE Robotics Autom. Soc. 8-13 May 1994. YR 1994. RN CCCC: 1050-4729/94/$03.00. AB A new method for designing an optimal time-delayed teleoperator control system based on Smith's principle is presented. First, an optimal delay-free teleoperator control system is designed with the human dynamics of visual and force trackings in the control loop and with the concept of telemonitoring force feedback. Then, an optimal time-delayed teleoperator control system is obtained by applying Smith's principle to the designed delay-free teleoperator control system and by modifying system parameters to achieve robustness to modeling errors. The proposed method provides an analytic design of a closed loop control structure for conventional teleprogramming facility and of a visual and kinesthetic man-machine interface required for time-delayed teleoperation. Simulation results are shown. 31 AN 4824387. AU Chen-M-Z. Zheng-Y-F. IN Dept. of Electr. Eng., Ohio State Univ., Columbus, OH, USA. TI Deform flexible beams by two manipulators through neural network learning. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1994. CT Proceedings 1994 IEEE International Conference on Robotics and Automation (Cat. No.94CH3375-3). San Diego, CA, USA. pp. 3180-5 vol.4. IEEE Robotics Autom. Soc. 8-13 May 1994. YR 1994. RN CCCC: 1050-4729/94/$03.00. AB In a previous paper (1993), the authors proposed an optimal trajectory for two manipulators to bend a flexible beam. The criterion was to minimize the interaction forces and moments between the beam and the end-effectors. It turned out that computation for specifying such a trajectory was complicated since an elliptic integral was involved in the computation. In this study, a circular arc is used as the motion trajectory of the two end-effectors. Since a circular arc is easy to specify, the computation time is greatly reduced. However, the interaction forces and moments become non-minimal. To overcome this problem, a neural network mechanism is proposed to adjust the trajectory in real-time such that the interaction forces and moments are reduced. The residual forces and moments are further minimized by a force feedback control mechanism. Simulation results are presented to verify the proposed method. 32 AN 4824235. AU Oh-Y-H. Chung-W-K. Jeong-K-W. Youm-Y. IN Dept. of Mech. Eng., Pohang Inst. of Sci. & Technol., South Korea. TI Implementation of passive hardware damper for force and impact control. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1994. CT Proceedings 1994 IEEE International Conference on Robotics and Automation (Cat. No.94CH3375-3). San Diego, CA, USA. pp. 937-43 vol.2. IEEE Robotics Autom. Soc. 8-13 May 1994. YR 1994. RN CCCC: 1050-4729/94/$03.00. AB This paper deals with the modeling and implementation of a robot system for force and impact control using a newly developed passive hardware damper. The system with passive damper is modeled and based on the model, the stability of the whole system with respect to force feedback gain is analyzed. The limitations of the conventional velocity feedback to produce damping characteristic is discussed. Experiments are performed with/without passive damper to verify the effectiveness of the passive damping method and it is shown that the passive damper can help the system make stable contact during the contact period especially with highly stiff environment. 33 AN 4817270. AU Colgate-J-E. IN Dept. of Mech. Eng., Northwestern Univ., Evanston, IL, USA. TI Coupled stability of multiport systems-theory and experiments. SO Transactions of the ASME. Journal of Dynamic Systems, Measurement and Control. vol.116, no.3. pp. 419-28. Sept. 1994. YR 1994. RN CCCC: 0022-0434/94/$3.00. AB This paper presents both theoretical and experimental studies of the stability of dynamic interaction between a feedback controlled manipulator and a passive environment. Necessary and sufficient conditions for "coupled stability"-the stability of a linear, time-invariant n-port (e.g., a robot, linearized about an operating point) coupled to a passive, but otherwise arbitrary, environment-are presented. The problem of assessing coupled stability for a physical system (continuous time) with a discrete time controller is then addressed. It is demonstrated that such a system may exhibit the coupled stability property; however, analytical, or even inexpensive numerical conditions are difficult to obtain. Therefore, an approximate condition, based on easily computed multivariable Nyquist plots, is developed. This condition is used to analyze two controllers implemented on a two-link, direct drive robot. An impedance controller demonstrates that a feedback controlled manipulator may satisfy the coupled stability property. A LQG/LTR controller illustrates specific consequences of failure to meet the coupled stability criterion; it also illustrates how coupled instability may arise in the absence of force feedback. Two experimental procedures-measurement of endpoint admittance and interaction with springs and masses-are introduced and used to evaluate the above controllers. Theoretical and experimental results are compared. 34 AN 4815480. AU Luciani-A. Cadoz-C. Florens-J-L. IN LIFIA-INPG, Grenoble, France. TI The CRM device: a force feedback gestural transducer to real-time computer animation. SO Displays. vol.15, no.3. pp. 149-55. July 1994. YR 1994. RN CCCC: 0141-9382/94/03/0149-07$10.00. AB Movements in images or sounds are naturally produced by physical objects under the action of forces. These forces can be natural, such as those produced by gravity, wind or turbulence, artificial, as produced by manufactured motors, or human. Thus, to produce and control synthetic movements, computer simulation of physical objects can be monitored by specific interfaces, which provide the simulation of force generators, or convey real human gestural intervents. In this paper, we focus on the last approach. An analysis of human gestures driving a physical object is presented together with a force feedback gestural transducer we have developed, the CRM or modular retroactive keyboard. Finally, we show the computer context and paradigm in which we have developed this device, called the Instrumental Communication Interface (ICI). 35 AN 4815307. AU Hirata-Y. Mizuguchi-T. Sato-M. Kawarada-H. IN Precision & Intelligence Lab., Tokyo Inst. of Technol., Yokohama, Japan. TI Virtual work space for assembly. SO Systems and Computers in Japan. vol.25, no.7. pp. 92-100. 15 June 1994. YR 1994. AB To implement a human interface for efficiently modeling 3-D shapes on a computer, a virtual works space enabling direct manipulation of a shape model on a computer similar to manipulating a real 3-D object must be constructed. In this virtual work space, the tactile and force sensations arising while the object is manipulated must be fed back to the person. We previously proposed the space interface device SPIDAR capable of force feedback to the person's fingertips. However, only one finger could be used in SPIDAR, so operations where the object is held were not possible. We extend SPIDAR and propose the space interface device SPIDAR II to implement a virtual work space where operations involving holding and moving objects are possible. This device measures the position of the minimum of the two fingers needed to manipulate objects and can provide tactile feedback to the fingertips while an object is being held. A prototype device is built and a virtual work space is constructed where holding and moving objects is possible. Further, an experiment is conducted to investigate the effect of tactile feedback to work operability in this virtual work space, and its effectiveness is confirmed. 36 AN 4811628. AU Singh-S-K. Bostrom-M. Popa-D-O. Wiley-C-W. IN Thayer Sch. of Eng., Dartmouth Coll., Hanover, NH, USA. TI Design of an interactive lumbar puncture simulator with tactile feedback. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1994. CT Proceedings 1994 IEEE International Conference on Robotics and Automation (Cat. No.94CH3375-3). San Diego, CA, USA. pp. 1734-9 vol.2. IEEE Robotics Autom. Soc. 8-13 May 1994. YR 1994. RN CCCC: 1050-4729/94/$03.00. AB Lumbar puncture for purposes of administering spinal or epidural anesthesia is a complex clinical skill which requires the clinician to precisely correlate a detailed mental map of hidden three-dimensional anatomy with tactile feedback from the spinal needle as it's being inserted. At Dartmouth, a collaborative work between the engineering and medical schools is aimed at developing a computer-based simulation utilizing high-resolution 3D graphics and a force-feedback device to simulate the "feel" of inserting the needle. This paper describes the mechanical design, hardware and software issues and some of the technical challenges being addressed in this project. 37 AN 4811627. AU Sato-T. Ichikawa-J. Mitsuishi-M. Hatamura-Y. IN Res. Center for Adv. Sci. & Technol., Tokyo Univ., Japan. TI A new micro-teleoperation system employing a hand-held force-feedback pencil. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1994. CT Proceedings 1994 IEEE International Conference on Robotics and Automation (Cat. No.94CH3375-3). San Diego, CA, USA. pp. 1728-33 vol.2. IEEE Robotics Autom. Soc. 8-13 May 1994. YR 1994. RN CCCC: 1050-4729/94/$03.00. AB This paper describes a new micro-teleoperation system that is inherently suitable for micro-object handling since it mitigates several drawbacks associated with human interface devices. The system uses an upward-facing CRT display monitor mounted beneath a table. An operator performs micro-tasks in a sitting posture at the table while looking down at the monitor with a touch sensor screen situated between the operator's arms. To execute these tasks, microscope-observed images of the target objects are utilized in conjunction with the touch sensor screen and a specially designed, pencil-shaped master manipulator having a force-feedback function. The system incorporates the following characteristic features: (1) Intuitive teleoperation is possible because coincidence of the operating and monitoring point is provided. (2) The pencil-shaped master manipulator enables sensitive bilateral micro teleoperation because of its light weight and small inertia for movement, and (3) With the side of the right hand fixed in a pen-holder grip, the operator uses the master manipulator to generate commands with a wide dynamic range of force feedback, i.e., the operator can simultaneously feel force feedback during operation from both pressure/slip sensory receptors on the fingertips and sensory receptors which detects stretching of the finger muscles. The stated features are proved experimentally by the constructed micro teleoperation prototype system. 38 AN 4811596. AU Tarn-T-J. Ning-Xi. Ramadorai-A-K. Bejczy-A-K. IN Dept. of Syst. Sci. & Math., Washington Univ., St. Louis, MO, USA. TI A versatile experimental system for dual-arm planning and control. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1994. CT Proceedings 1994 IEEE International Conference on Robotics and Automation (Cat. No.94CH3375-3). San Diego, CA, USA. pp. 1515-20 vol.2. IEEE Robotics Autom. Soc. 8-13 May 1994. YR 1994. RN CCCC: 1050-4729/94/$03.00. AB This paper describes a distributed computing and control architecture for experiments in dual-arm sensor-based planning and control. The system comprises of two PUMA 560 robots with state-of-the-art joint-level motion controllers. These controllers have accurate joint position and velocity measurement, an accurate joint calibration system, and six-axis wrist force/torque sensors with optical fiber communication with the controller. A high-power Silicon Graphics workstation, through a shared memory interface with the joint-level controllers, provides a task-level command and control capability. A variety of control schemes can be easily implemented on this system. A servo rate of 1000 Hz, without interpolation, has been achieved for task-level servo schemes with force feedback. The experimental results presented here demonstrate the performance capabilities of the system. 39 AN 4810626. AU Repperger-D-W. Phillips-C-A. Chelette-T-L. IN Armstrong Lab., US Air Force Inst. of Technol., Wright-Patterson AFB, OH, USA. TI The application of force feedback control schemes from studies on robotic systems to analyze a teleoperation system involving humans. SO Published by: IEEE. New York, NY, USA. 1993. CT Second IEEE Conference on Control Applications (Cat. No.93CH3243-3). Vancouver, BC, Canada. pp. 41-6 vol.1. IEEE Control Syst. Soc. 13-16 Sept. 1993. YR 1993. RN CCCC: CH3243-3/93/0000-0041$1.00. AB The application of theoretical concepts and other principles from studies of force feedback control systems in robotics can be used to better understand a teleoperative system. Within the context of a robotic system, the teleoperation problem can be viewed as a strictly force control system in which the end-effector must maintain a specified force pattern on the environment. Using this analogy, the environment may be modelled as being subjected to disturbances or an active compliance. Such technical issues as stability, performance, controllability, and other developments in the control systems literature now easily extend to the area of teleoperation involving humans. To illustrate this procedure, an analysis is conducted of a system from an ongoing experiment. This experiment involves handicapped people and normals participating in a study to analyze the effect on performance of different types of force feedback algorithms and target tracking tasks. 40 AN 4809441. AU Sato-M. Sawatari-M. Ishii-M. Hirata-Y. Kawarada-H. IN Precision & Intelligence Lab., Tokyo Inst. of Technol., Yokohama, Japan. TI The effect of force-feedback in the virtual work space. SO Transactions of the Institute of Electronics, Information and Communication Engineers D-II. vol.J77D-II, no.8. pp. 1656-62. Aug. 1994. YR 1994. AB To develop a human interface for three-dimensional modeling, a new interface device has been proposed for constructing a virtual work space where we can manipulate object models directly. The paper discusses the effect of force-feedback on a pick-and-place task in the virtual work space. We first analyze a manipulation in the pick-and-place task. After that, the virtual work space, including force sensation, is constructed for this task. Finally the effect of force-feedback, especially gravity-feedback, is clarified through the experiment on the pick-and-place task. As a result, when the force-feedback is given, this task can be accomplished more accurately, promptly and comfortably. 41 AN 4806033. AU Dumay-A-C-M. Jense-G-J. IN TNO Phys. & Electron. Lab., The Hague, Netherlands. TI On the feasibility of virtual environments in medicine. SO Published by: AGARD. Neuilly sur Seine, France. 1994. CT Virtual Interfaces: Research and Applications (AGARD-CP-541). Lisbon, Portugal. pp. 3/1-8. 18-22 Oct. 1993. YR 1994. AB Virtual environments allow a human to interact with a (computer) system in such a way that a high level of presence in a computer-synthesised world is experienced. In principle, all human senses are involved with the interaction. Many applications may benefit from this type of human-machine interfacing, however, little have emerged so far for medicine. We elaborate on some realistic potential applications of virtual environment technology in the field of medicine. These applications can be found in education/training, therapy, surgery, rehabilitation, diagnosis, telemedicine and biomechanics. The value to be added to these applications by VE technology lies in the fact that patient data or patient models may be moderated to the physician in a more intuitive and natural manner. Despite these potentials, the short-term feasibility of these applications can be put into question for various reasons. Firstly, the current generation of display devices have a resolution that may show to be too low to achieve a sufficiently high degree of realism for medical applications. Secondly, there are no commercially-available actuators for tactile and force feedback which the physician desperately need for the simulation of the contact with the (virtual) patient. Thirdly, the enormous computing power required for these applications needs (yet) a considerable investment. With these limitations in mind, we believe that we are at the cradle of a whole new generation of VE applications in medicine. 42 AN 4802338. AU Pi-Cheng-Tung. Yen-Pu-Hsu. IN Dept. of Mech. Eng., Nat. Central Univ., Chung-Li, Taiwan. TI Application of fuzzy control to an inserting operation. SO Fuzzy Sets and Systems. vol.66, no.3. pp. 267-81. 26 Sept. 1994. YR 1994. RN CCCC: 0165-0114/94/$07.00. AB Because of the difficulty of dynamic equations for the inserting operation and the advantage of fuzzy control for easy execution without knowledge of the mathematical models, we used the force feedback signal measured by a force sensor and a fuzzy controller to regulate the position of a peg. The control strategy includes two control loops. In one, a PID position controller moves the peg's vague position nearer to the hole, and in the other, the fuzzy controller regulates the final position according to the contact force. Between the two control loops, we use an index to activate a switch. To verify the proposed control strategy, we performed experiments with a Cartesian manipulator system driven by AC servo motors. The experimental results reveal that we can insert a peg into a hole with a fitting clearance of less than 0.01 mm. 43 AN 4801977. AU Bronowicki-A. Innis-J. Casteel-S. Dvorsky-G. Alvarez-O. Rohleen-E. IN TRW Space & Technol. Div., One Space Park, Redondo Beach, CA, USA. TI Active vibration suppression using modular elements. SO Proceedings of the SPIE - The International Society for Optical Engineering. vol.2190. pp. 717-28. 1994. CT Smart Structures and Materials 1994. Smart Structures and Intelligent Systems. Orlando, FL, USA. SPIE. 14-16 Feb. 1994. YR 1994. RN CCCC: 0 8194 1485 9/94/$6.00. AB A system for active suppression of structural vibrations has been developed. The system consists of piezoelectric ceramic actuator and sensor elements which can be either bonded on to or embedded in structural components. For active damping, these are placed at locations of high modal strain energy. For active isolation, locations of high disturbance transmissibility are chosen. Small analog and digital control electronics units have been developed which include all sensing, processing and actuator drive electronics. The analog unit is appropriate for active damping using strategies such as positive position and integral force feedback. Damping levels in structures has been increased from 0.1% to 100% using a single analog controller. The digital system is capable of executing any algorithm having two inputs and two outputs. Active damping using feedback and active force cancellation using feedforward have been demonstrated. Block diagrams, specifications, photographs and test results describing the elements of the modular vibration suppression system are presented. 44 AN 4794782. AU Rupp-A. Velastin-S-A. IN Dept. of Electron. & Electr. Eng., King's Coll., London, UK. TI A gripper and sensor system for controlled slip and force. SO Published by: IEEE. New York, NY, USA. 1994. CT ISIE '94. 1994 IEEE International Symposium on Industrial Electronics. Symposium Proceedings (Cat. No.94TH0670-0). Santiago, Chile. pp. 329-34. IEEE Ind. Electron. Soc. Catholic Univ. Chile. IEEE Chile Sect. Chilean Assoc. Autom. Control. 25-27 May 1994. YR 1994. AB The paper describes the development of a robot gripper, sensors and associated electronics suitable for controlling slippage and contact force. A typical application is the handling of glass test tubes in an automated medical analysis laboratory. Through force control, the gripper first holds an object, then repeatedly releases and regrasps it for controlled slip. The basic mechanical principle consists of a rolling cylinder in direct contact with the (cylindrical) object, forming a cylinder-cylinder pivot with 5 degrees of freedom. A stable grasp is achieved by a finger/counter-finger arrangement with 3 contact points. In the left finger, contact force is reflected in the pivots of the roll and measured by piezoresistive force sensors. In the right finger, motion is measured by optical encoders. Analog electronics deal with gripper motor control and signal processing for the force sensors. Digital circuits handle the motion measurement from the optical encoders, A/D conversion of force sensor outputs and force feedback for motor control and communications with an external computer. The proposed design has been built and tested using an industrial SCARA robot. 45 AN 4794393. AU Bencsik-A-L. Rudas-I-J. IN Banki Donat Polytech., Budapest, Hungary. TI Mechatronic development for force feedback teleoperation system. SO Published by: IEEE. New York, NY, USA. 1993. CT Proceedings of the IECON '93. International Conference on Industrial Electronics, Control, and Instrumentation (Cat. No.93CH3234-2). Maui, HI, USA. pp. 57-61 vol.1. IEEE Ind. Electron. Soc. Soc. Ind. Control Eng. Japan. 15-19 Nov. 1993. YR 1993. RN CCCC: 0 7803 0891 3/93/$03.00. AB In this paper the authors present the mechatronic development of a hydraulic force reflecting master-slave system which is applicable for industrial robot control. The methods of force reflection is analysed. The new universal master-slave is described from technical and from economic points of view. A master-slave is also demonstrated which is suitable for a four degrees of freedom force feedbacking of robot manipulators when there are built-in integral force perceptions fitted either to joints or to the end effector of the robot. 46 AN 4794391. AU Buss-M. Hashimoto-H. IN Inst. of Ind. Sci., Tokyo Univ., Japan. TI Intelligent cooperative manipulation system. SO Published by: IEEE. New York, NY, USA. 1993. CT Proceedings of the IECON '93. International Conference on Industrial Electronics, Control, and Instrumentation (Cat. No.93CH3234-2). Maui, HI, USA. pp. 45-50 vol.1. IEEE Ind. Electron. Soc. Soc. Ind. Control Eng. Japan. 15-19 Nov. 1993. YR 1993. RN CCCC: 0 7803 0891 3/93/$03.00. AB Proposes an intelligent cooperative manipulation system-ICMS for human-machine cooperative manipulation. Using a force feedback sensor glove and virtual environment as human interfaces, essential data describing the performed manipulation task can be acquired and accumulated in a manipulation skill data base. A model for representation of hand manipulation skill is proposed. Using this model an example shows how human skill can be acquired and transferred to be executed by a robotic hand. 47 AN 4791766. AU Brimhall-O-D. Hasser-C-J. IN Tech. Res. Associates, Inc., Salt Lake City, UT, USA. TI Magnetostrictive linear devices for force reflection in dexterous telemanipulation. SO Proceedings of the SPIE - The International Society for Optical Engineering. vol.2190. pp. 508-19. 1994. CT Smart Structures and Materials 1994. Smart Structures and Intelligent Systems. Orlando, FL, USA. SPIE. 14-16 Feb. 1994. YR 1994. RN CCCC: 0 8194 1485 9/94/$6.00. AB Anthropomorphic exoskeletal systems with full force feedback are desired for intuitive telemanipulation. Current dexterous force-reflecting hand masters are fundamentally limited by available force actuators. Multiple degree of freedom dexterous exoskeletal systems are especially sensitive to mass, volume, force, velocity and geometric constraints. The authors discuss desired operational parameters and targets for ideal dexterous force feedback actuation. New resistive and active actuators, using Terfenol-D magnetostrictive driven elements, are proposed. Simple resistive and active magnetostrictive concepts, prototypes, and devices are demonstrated and evaluated. 48 AN 4783879. AU Karatzas-L-S. Keating-D-A. Usher-M-J. IN Dept. of Cybern., Reading Univ., UK. TI A practical optical force-feedback microphone. SO Transactions of the Institute of Measurement and Control. vol.16, no.2. pp. 75-85. 1994. YR 1994. AB A novel technique of measuring diaphragm displacement in microphones using a laser-diode Fabry-Perot system is presented. The microphone diaphragm is held within an electrostatic force-feedback loop so as to improve the performance. A second loop operates around the laser, for noise minimisation purposes. Following a brief introduction to the subject of optical detection in microphones, the modified Fabry-Perot interferometer is described and the complete system with the two feedback loops presented. The characteristics of the laser driver and laser diode are examined. Theoretical responses are shown, for different cases, and noise calculations yield the dynamic ranges without feedback. The effect of feedback is then examined, both around the laser (electronic) and around the microphone SNR capsule (electrostatic), and the dynamic ranges are recalculated to show the advantages of feedback. Intended directions for further research are also discussed. 49 AN 4778751. AU Kanestrom-R-K. Egeland-O. IN Dept. of Eng. Cybern., Trondheim Univ., Norway. TI Design of a nonlinear active vibration damping system for a flexible truss structure. SO Published by: IEEE. New York, NY, USA. 1993. CT Proceedings of the 32nd IEEE Conference on Decision and Control (Cat. No.93CH3307-6). San Antonio, TX, USA. pp. 1404-5 vol.2. IEEE Control Syst. Soc. 15-17 Dec. 1993. YR 1993. RN CCCC: 0191-2216/93/$3.00. AB A multivariable nonlinear controller is proposed for vibration suppression of flexible space structures. The controller gain which precedes the integrator in the integral force feedback scheme is exchanged with a gain consisting of a constant term added to a term proportional to the force measurement signal. This approach provides rapid cancellation of large deflections maintaining low noise sensitivity. L/sub 2/ is proved and experimental results show improved performance compared to the linear integral force feedback with constant gain. 50 AN 4776203. AU Langrana-N-A. Burdea-G. Lange-K. Gomez-D. Deshpande-S. IN Rutgers State Univ. of New Jersey, Piscataway, NJ, USA. TI Dynamic force feedback in a virtual knee palpation. SO Artificial Intelligence in Medicine. vol.6, no.4. pp. 321-33. Aug. 1994. YR 1994. RN CCCC: 0933-3657/94/$07.00. AB A virtual model of a knee joint with muscles, ligaments and bones has been developed. This model includes realistic 3D surface deformation and tissue stiffnesses. Tissue and bone deformation (palpation) produces real-time force feedback to the user hand wearing a DataGlove and Rutgers Master. Collision detection algorithms determine when and where the virtual hand palpates the surface model. This user interaction with the muscles and bones of a human knee model may be used as a training and planning tool for knee surgery. 51 AN 4776200. AU Satava-R-M. IN COL, US Army Med. Corps, Special Assistant in Biomedical Technol., Arlington, VA, USA. TI Emerging medical applications of virtual reality: a surgeon's perspective. SO Artificial Intelligence in Medicine. vol.6, no.4. pp. 281-8. Aug. 1994. YR 1994. RN CCCC: 0933-3657/94/$07.00. AB Medical applications for virtual reality (VR) technologies are just beginning to emerge. These include VR surgical simulators, telepresence surgery, complex medical database visualization, and rehabilitation. These applications are mediated through the computer interface and embody VR as an integral part of a paradigm shift in the field of medicine. The Green Telepresence Surgery System consists of two components, the surgical workstation and the remote worksite. At the remote site there is a 3D camera system and responsive manipulators with sensory input. At the workstation there is a 3D monitor and dexterous handles with force feedback. The VR surgical simulator is a stylized recreation of the human abdomen with several essential organs. Using a head-mounted display and Dataglove, a person can learn anatomy from a new perspective by 'flying' inside and around the organs, or can practice surgical procedures with a scalpel and clamps. Database visualization creates 3D images of complex medical data for new perspectives in analysis. VR applications in rehabilitation medicine permit impaired individuals to perform tasks not otherwise available to them, allow accurate assessment and therapy for their disabilities, and help architects understand their critical needs in public or personal space. And to support these advanced technologies, the operating room and hospital of the future will be first designed and tested in virtual reality, bringing together the full power of the digital physician. 52 AN 4755369. AU Bielefeldt-H. Horsch-I. Krausch-G. Lux-Steiner-M. Mlynek-J. Marti-O. IN Dept. of Phys., Konstanz Univ., Germany. TI Reflection-scanning near-field optical microscopy and spectroscopy of opaque samples. SO Applied Physics A (Solids and Surfaces). vol.A59, no.2. pp. 103-8. Aug. 1994. YR 1994. AB Opaque samples are imaged by scanning near-field optical microscopy (SNOM) in reflection mode: a quartz glass fiber tip is used both to illuminate the sample and to collect light locally reflected from or emitted by the surface. The collected light is coupled out by a 2*2 fiber coupler and fed into a grating spectrometer for spectral analysis at each sampled point. The tip-sample distance is controlled by a shear-force feedback system. The simultaneous measurement of topography and optical signals allows an assessment of imaging artifacts, notably topography-induced intensity changes. It is demonstrated that an optical reflectance contrast not induced by topographic interference can be found on suitable samples. Local spectral analysis is shown in images of a photoluminescent layer. 53 AN 4753555. AU Tarn-T-J. Bejczy-A-K. Ning-Xi. Ramadorai-A-K. IN Dept. of Syst. Sci. & Math., Washington Univ., St. Louis, MO, USA. TI Distributed control architecture for a sensor-driven dual arm system. SO Mechatronics. vol.4, no.5. pp. 481-502. Aug. 1994. YR 1994. RN CCCC: 0957-4158/94/$7.00+0.00. AB A distributed computing and control architecture for sensor-based control of a dual arm system is described. The system comprises of two PUMA 560 robots with state-of-the-art joint level motion controllers for accurate joint position and velocity measurement, an accurate joint calibration system, and six-axis wrist force/torque sensors with optical fiber links with the controller. A Silicon Graphics workstation, through a shared memory interface with the joint-level controllers, provides a task-level command and control capability. A computer vision system, with two CCD cameras, is also interfaced to the workstation. A variety of control schemes may be implemented on this system. A servo rate of 1000 Hz, without interpolation, has been achieved for task-level servo schemes with force feedback. The experimental results presented demonstrate the performance capabilities of the system. 54 AN 4740447. AU Lee-S. Lee-H-S. IN Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA. TI Teleoperator control system design with human in control loop and telemonitoring force feedback. SO Published by: IEEE. New York, NY, USA. 1992. CT Proceedings of the 31st IEEE Conference on Decision and Control (Cat. No.92CH3229-2). Tucson, AZ, USA. pp. 2674-9 vol.3. IEEE. 16-18 Dec. 1992. YR 1992. AB A design methodology for an advanced teleoperator control system using the paradigm of telemonitoring is presented. Human dynamics reacting to visual and kinesthetic force feedback is modeled and incorporated into the control loop for designing and evaluating teleoperator control systems. Monitoring force feedback is proposed for achieving a new kinesthetic coupling between the human operator and manipulators under significant communication time delay and shared control. A comparative study shows that (1) teleoperator control systems designed without human dynamics in the control loop become valid when a human is added to the control loop, and that (2) teleoperator control systems aimed at achieving telepresence or a passive system suffer from either poor performance or instability under communication time delay. Based on the comparative study, an optimal structure of the teleoperator system for resolving considerable communication time delay is proposed. 55 AN 4737894. AU Shi-Weixiang. Cao-Binggang. Wang-Sunan. IN Xian Jiaotong Univ., China. TI The electro-hydraulics servo techniques in China. SO Journal of the Japan Hydraulics and Pneumatics Society. vol.25, no.3. pp. 415-24. May 1994. YR 1994. AB As early as 1950s, the electrohydraulic servo techniques had been applied in China. In the 1970s, the electrohydraulic servo techniques were introduced into China from Moog Corp., Vickers Corp. in the USA and Rexroth Corp. in Germany. Then two types of servo valves, QDY and DY, were produced in China. The former uses a torque motor with flapper-nozzle and force feedback and has relatively high frequency response. The latter is a moving-coil two-stage spool type of servo valve, which has large flow and low frequency response. Since 1980s, the quality of the servo valves was improved gradually with the stimulation of electrohydraulic servo techniques in the USA, Germany and Japan. Meanwhile, the electrohydraulic proportional technique was also developed. In this aspect, a flow sensing position/force feedback type of proportional valve had been put into production. Now, the electrohydraulic servo technique has been applied widely in China. Representative introductions are given in this paper. 56 AN 4734428. AU Qiao-H. Dalay-B-S. Parkin-R-M. IN Dept. of Mech. Eng., De Montfort Univ., Leicester, UK. TI Precise robotic chamferless peg-hole insertion operation without force feedback and remote centre compliance (RCC). SO Proceedings of the Institution of Mechanical Engineers, Part C (Journal of Mechanical Engineering Science). vol.208, no.C2. pp. 89-104. 1994. YR 1994. AB Robots can be widely used in the industrial assembly operation if the task can be performed with high precision, high speed and with low cost. Peg-hole insertion is a fundamental operation whose problems have been the focus of much work. In the passive accommodation solution, remote centre compliance (RCC) is used to perform chamfered peg-hole insertion. The principle exploited involves using RCC as a mechanical map which transfers the translational and angular errors, between the peg and the hole, into corrective motion. The potential advantages of minimized cycle times are offset by the limited precision. This contrasts with techniques exploiting active accommodation which use a force sensor to arrive at the deviation, between the peg and hole axes, to achieve chamferless insertion. A strategy is developed here that uses neither of these additional accessories but instead exploits features of both techniques with defined initial conditions. The immediate advantages of reduced hardware complexity are supplemented by evidence of trials. These were based on a 31.99 mm diameter peg and a hole with a diameter clearance of 0.02 mm. The results showed that the algorithm operated reliably with small clearances and with minimum cycle times. This confirms its potentially wide application in industry where its simplicity can be fully exploited. 57 AN 4731048. AU Hirose-M. Hirota-K. Edited by: Salvendy-G. Smith-M-J. IN Fac. of Eng., Tokyo Univ., Japan. TI Surface display and synthetic force sensation. SO Published by: Elsevier. Amsterdam, Netherlands. 1993. CT Human-Computer Interaction. Proceedings of the Fifth International Conference on Human-Computer Interaction (HCI International '93). Orlando, FL, USA. pp. 645-50 vol.2. AT&T. Fuji Electr. Co. JGC Corp. NEC Corp. Purdue Univ. Univ. Central Florida. Univ. Wisconsin-Madison. 8-13 Aug. 1993. YR 1993. AB In the real world, the sensation of force is felt when a real object comes into contact with a part of our body. This fact motivated us to the idea of creating artificial touch sensation by using some type of force feedback device. A prototype display device for simulating force sensation based on this idea was developed and called surface display. In previous research, the touch sensation was often discussed and many prototypes for force feedback were developed. However, most of these devices were designed from a conventional force feedback perspective, which has been developed mainly in the robotics field. In this paper, another approach for designing a force feedback device, a 'mock-surface' method, is presented. Several prototype devices were implemented based on the approach and assessments were made from various point of view. This paper describes the conceptual design and implementation process as well as some experimental results. 58 AN 4729865. AU Haugland-M-K. Hoffer-J-A. Sinkjaer-T. IN Dept. of Med. Inf. & Image Anal., Aalborg Univ., Denmark. TI Skin contact force information in sensory nerve signals recorded by implanted cuff electrodes. SO IEEE Transactions on Rehabilitation Engineering. vol.2, no.1. pp. 18-28. March 1994. YR 1994. RN CCCC: 1063-6528/94/$04.00. AB When functional neuromuscular stimulation (FNS) is used to restore the use of paralyzed limbs after a spinal cord injury or stroke, it may be possible to control the stimulation using feedback information relayed by natural sensors in the skin. In this study the authors tested the hypothesis that the force applied on glabrous skin can be extracted from the electroneurographic (ENG) signal recorded from the sensory nerve. They used the central footpad of the cat hindlimb as a model of the human fingertip and recorded sensory activity with a cuff electrode chronically implanted around the tibial nerve. Their results showed that the tibial ENG signal, suitably filtered, rectified, and smoothed carries detailed static and dynamic information related to the force applied on the footpad. The authors derived a mathematical model of the force-ENG relation that provided accurate estimates of the ENG signal for a wide range of force profiles, amplitudes, and frequencies. Once fitted to data obtained in one recording session, the model could be made to fit data obtained in other sessions from the same cat, as well as from other cats, by simply adjusting its overall gain and offset. However, the model was noninvertible; i.e., the force could not be similarly predicted from the ENG signal, unless additional assumptions or restrictions were introduced. The authors discuss the reasons for these findings and their implications on the potential use of nerve signals as a source of continuous force feedback information suitable for closed-loop control of FNS. 59 AN 4725029. AU Vukobratovic-M. Stokic-D. TI A survey of joint force feedback methods for controlling manipulation robots. SO Tekhnicheskaya Kibernetika. pp. 175-90. TR Journal of Computer and Systems Sciences International. vol.32, no.2. pp. 89-101. March-April 1994. RN CCCC: 1064-2307/94/0002-0089. AB The problems of achieving both coarse and precision manipulator control by means of joint force feedback are examined. One of the purposes of this paper is to provide a survey of the establishment and development over the last two decades of the idea of employing joint force feedback. A variety of control designs containing joint torque feedback loops are examined. The main advantages of this approach are discussed. Joint torque feedback is promising for compensating dynamic effects in robot control without requiring real-time calculation of robot dynamics; the control system is robust to changes in parameters, etc. Various problems associated with the design and fabrication of torque sensors are examined. Particular attention is devoted to the proposed approach in hybrid position-force control systems. 60 AN 4706244. AU Taylor-R-M-II. Robinett-W. Chi-V-L. Brooks-F-P-Jr. Wright-W-V. Williams-R-S. Snyder-E-J. IN Dept. of Comput. Sci., North Carolina Univ., Chapel Hill, NC, USA. TI The Nanomanipulator: a virtual-reality interface for a scanning tunneling microscope. SO Published by: ACM. New York, NY, USA. 1993. CT Computer Graphics Proceedings. Anaheim, CA, USA. pp. 127-34. ACM. 1-6 Aug. 1993. YR 1993. RN CCCC: 0 89791 601 8/93/008/0127$01.50. AB We present an atomic-scale teleoperation system that uses a head-mounted display and force-feedback manipulator arm for a user interface and a Scanning Tunneling Microscope (STM) as a sensor and effector. The system approximates presence at the atomic scale, placing the scientist on the surface, in control, while the experiment is happening. A scientist using the Nanomanipulator can view incoming STM data, feel the surface, and modify the surface (using voltage pulses) in real time. The Nanomanipulator has been used to study the effects of bias pulse duration on the creation of gold mounds. We intend to use the system to make controlled modifications to silicon surfaces. 61 AN 4705625. AU Yao-B. Tomizuka-M. IN Dept. of Mech. Eng., California Univ., Berkeley, CA, USA. TI Adaptive control of robot manipulators in constrained motion. SO Published by: American Autom. Control Council. Evanston, IL, USA. 1993. CT Proceedings of the 1993 American Control Conference (IEEE Cat. No.93CH3225-0). San Francisco, CA, USA. pp. 1128-32 vol.2. IEEE. American Autom. Control Council. IFAC. et al. 2-4 June 1993. YR 1993. AB The adaptive motion and force control of robot manipulators in constrained motion in the presence of parametric uncertainties both in the robot and surface coefficient of dry friction is considered. A new constrained dynamic model is obtained to account for the effect of contact surface friction. An adaptive law is suggested with unknown parameters updated by both motion and force tracking errors to guarantee asymptotic motion and force tracking without any persistent excitation condition to be satisfied. The suggested controller includes an expected PI (proportional plus integral) type force feedback control structure with a low proportional force feedback gain. The acausality problem is analyzed by a quasi-static method to show that allowable proportional force feedback gain is severely limited in implementation. With a slight modification to the updating law, the controller also possesses robustness to bounded measurement noise and disturbances. 62 AN 4703210. AU Mei-Hua-Liu. IN Inst. fur Regelungstech., Tech. Hochschule Darmstadt, Germany. TI Development of a force-controlled robotic deburring system with the help of fuzzy logic. SO Automatisierungstechnik. vol.42, no.5. pp. 218-24. May 1994. YR 1994. AB This paper presents a robotic deburring strategy based on force feedback control and fuzzy logic. By controlling the deburring force in the normal and tangential directions of the desired trajectory, positional inaccuracies and unknown burr sizes are detected online and real-time motion connections are conducted in such a way that the positional inaccuracies are compensated and unknown burr sizes are completely removed. With the use of fuzzy logic control controller parameters are adjusted automatically according to working conditions, disturbances involved in data measurement are suppressed, and smooth behaviour in the compensation of the positional inaccuracies is achieved. Implementation of and experimental results about the proposed deburring strategy are described and its main features are discussed in relation with a conventional PID controller. 63 AN 4696786. AU Sinclair-M. Peifer-J. IN Georgia Inst. of Technol., Atlanta, GA, USA. TI Socially correct virtual reality: surgical simulation. SO Virtual Reality World. vol.2, no.4. pp. 64-6. July-Aug. 1994. YR 1994. RN CCCC: 1060-9547/94/$15.00+0. AB A proof-of-concept eye surgery simulation has been developed at the Georgia Institute of Technology as a collaboration with the Medical College of Georgia. This simulator provides both visual and force feedback, while a student surgeon operates on a computer-generated model of the eye in a virtual environment. Historically, physicians have learned new surgical procedures through passive observation and active practice on cadavers or animals, and then performing the procedure on patients under the supervision of an experienced surgeon. In the future, computer simulation will allow physicians to practice surgical procedures in a virtual environment in which there is no risk to patients. Mistakes can be immediately erased, and the procedure can be reviewed from new, insightful perspectives or situations that are impossible in the real world. 64 AN 4690867. AU Paetsch-W. von-Wichert-G. IN Dept. of Control Syst. Theor. & Robotics, Tech. Univ. of Darmstadt, Germany. TI Solving insertion tasks with a multifingered gripper by fumbling. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1993. CT Proceedings IEEE International Conference on Robotics and Automation (Cat. No.93CH3247-4). Atlanta, GA, USA. pp. 173-9 vol.3. IEEE. 2-6 May 1993. YR 1993. RN CCCC: 0 8186 3450 2/93/$3.00. AB Part mating with a multifingered gripper mainly comprises two areas, i.e., the control of the gripper or hand and the strategies to solve the task. The problem is made more difficult by the uncertainties from mechanical, sensor or control errors within the gripper system or the parts to be assembled. The authors examine how to find and to realize a hand behavior, which solves the task under the assumption that the system is heavily influenced by the uncertainties mentioned. The problem is solved by a force feedback loop, containing a comparatively simple mathematic description of strategies applied in parallel. The proof of the efficiency of the approach is given. Results of various experiments are presented. 65 AN 4687189. AU Yao-B. Tomizuka-M. IN Dept. of Mech. Eng., California Univ., Berkeley, CA, USA. TI Adaptive coordinated control of multiple manipulators handling a constrained object. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1993. CT Proceedings IEEE International Conference on Robotics and Automation (Cat. No.93CH3247-4). Atlanta, GA, USA. pp. 624-9 vol.1. IEEE. 2-6 May 1993. YR 1993. RN CCCC: 0 8186 3450 2/93/$3.00. AB Adaptive motion, internal force, and external contact force control of multiple manipulators handling a constrained object is achieved. Parametric uncertainties may exist in the manipulator and in the object as well as in the friction coefficients of contact surfaces. A set of transformed dynamic equations are obtained in the joint space, in which internal force and external contact force have the same form and, thus, can be dealt with in the same way. Based on some particular properties of a reformulated motion and force equation, and adaptive algorithm is developed with unknown parameters updated by both motion and force tracking error. The controller guarantees asymptotic motion and force tracking without any persistent excitation condition and has a proportional-integral (PI) force feedback control structure with a low P-gain, so that acausality is avoided. Robustness to bounded velocity and force measurement noise as well as to disturbances of the controller is discussed. 66 AN 4687151. AU Parker-N-R. Salcudean-S-E. Lawrence-P-D. IN Dept. of Electr. Eng., British Columbia Univ., Vancouver, BC, Canada. TI Application of force feedback to heavy duty hydraulic machines. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1993. CT Proceedings IEEE International Conference on Robotics and Automation (Cat. No.93CH3247-4). Atlanta, GA, USA. pp. 375-81 vol.1. IEEE. 2-6 May 1993. YR 1993. RN CCCC: 0 8186 3450 2/93/$3.00. AB The design and implementation of a force-reflecting controller for conventional heavy duty hydraulic machines are described. The unsuitability of direct force feedback with rate control has been shown analytically and confirmed on a simulator of a typical hydraulic machine. A stiffness control scheme to circumvent this problem was developed and used successfully in controlling the endpoint force on a CAT 215 log loader to better than 10% of a typical working load. A magnetically levitated wrist was used as a force-reflecting master, and the endpoint forces were obtained from hydraulic cylinder pressures. 67 AN 4687128. AU Wapenhans-H. Seyfferth-W. Pfeiffer-F. IN Lehrstuhl B fuer Mechanik. Tech. Univ. Munchen, Germany. TI Robotic force control for flexible assembly. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1993. CT Proceedings IEEE International Conference on Robotics and Automation (Cat. No.93CH3247-4). Atlanta, GA, USA. pp. 225-31 vol.1. IEEE. 2-6 May 1993. YR 1993. RN CCCC: 0 8186 3450 2/93/$3.00. AB The authors present a complete design procedure for determining an optimal force control for assembly tasks while assuring stability. Based on a constrained motion model of the robot, including elasticity of joints and force sensor, a custom design scheme may be applied for individual types of mating tasks. The approach guarantees separation of position and force controlled cartesian directions of the robot endpoint by complementary input/output decoupling. Position feedback parameters are optimized to obtain a maximum stability reserve and force feedback parameters are optimized to minimize settling time. Controller behavior is then predicted by the simulation of the potentially unsteady system dynamics including time-varying constraints on the workpiece. The design process is illustrated for a peg-in-hole insertion and verified by experimental results from a laboratory robot. 68 AN 4687109. AU Wilfinger-L-S. Wen-J. Murphy-S. IN Dept. of Electr.-Comput.-Syst. Eng., Rensselaer Polytech. Inst., Troy, NY, USA. TI Integral force control with robustness enhancement. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1993. CT Proceedings IEEE International Conference on Robotics and Automation (Cat. No.93CH3247-4). Atlanta, GA, USA. pp. 100-5 vol.1. IEEE. 2-6 May 1993. YR 1993. RN CCCC: 0 8186 3450 2/93/$3.00. AB Three robustness enhancement modifications to the standard integral force feedback control are presented. These modifications help to reduce the initial impact force of the robot gripper on the environment and maintain contact with the environment in the presence of disturbances. By combining all of the modifications into the force integral feedback algorithm, the best features of each modification are obtained. The result is a force control algorithm which maintains contact with a rigid surface and remains stable in the presence of large force disturbances. 69 AN 4683594. AU Gao-Weibing. Cheng-Mian. Xiao-Di. IN Seventh Res. Div., Beijing Univ. of Aeronaut. & Astronaut., China. TI Force control for tracking a set of tasks in presence of constraints. SO Control Theory & Applications. vol.11, no.1. pp. 40-50. Feb. 1994. YR 1994. AB A new approach to tracking tasks by robots in the presence of environmental constraints is proposed. Since the dynamic equations of a rigid object are written in a component form with respect to axes fixed with the object, a new model of constraints is given in a very simple form as linear functions of velocity components. As a result, the system of differential equations of motion of the object is automatically decomposed into two subsystems: equations of motion and equations of reactive force. Two force feedback schemes are developed. A hierarchical architecture is established for the overall control strategy such that the robot can trade a set of different objects for different desired motions. 70 AN 4683572. AU Jiang-Fan. Feng-Zuren. Shi-Ren. IN Dept. of Inf. & Control Eng., Xi'an Jiaotong Univ., China. TI An adaptive impedance control algorithm of robot manipulators. SO Control Theory & Applications. vol.10, no.6. pp. 638-43. Dec. 1993. YR 1993. AB In accordance with the robot motion control with unknown manipulator parameters and uncertain payloads, an adaptive impedance control algorithm of Pithy type is presented in this paper. The algorithm can ensure manipulators to track the desired impedance model and can strictly guarantee the asymptotic stability of the tracking error as well as the global stability of the manipulator and its environment. In addition, the control approach without direct force feedback is also discussed. 71 AN 4681558. AU Faucett-T. Westfall-S. IN OECO Corp, Milwaukie, OR, USA. TI A highly flexible automated odd-form component assembly cell. SO Published by: IEEE. New York, NY, USA. 1993. CT APEC '93. Eighth Annual Applied Power Electronics Conference and Exposition. Conference Proceedings 1993 (Cat. No.93CH3271-4). San Diego, CA, USA. pp. 234-9. IEEE. Power Sources Manuf. Assoc. 7-11 March 1993. YR 1993. RN CCCC: 0 7803 0983 9/93/$3.00. AB The authors describe the development of an automated odd-form assembly cell utilizing two high-speed, random accessed, elevator-type component tray feeders with 16 trays each, a SCARA-type pick-and-place robot, a force feedback servo-driven gripper, an active vision correction system, and a variable-width conveyor transport. This system represents a truly flexible, low cost, automated odd-form assembly cell. It features a minimum of 32 different odd-form components online, and provides fast component or product changeover time without the need or expense of multiple external feeders or feeder racks. The component feeder system used on this cell offers a simple and low-cost tooling solution for odd-form components compared to any previous odd-form assembly cell. 72 AN 4681423. AU Middleton-T. Edited by: Murphy-H-J. IN SRI Int., Menlo Park, CA, USA. TI Matching virtual reality solutions to special needs. SO Published by: California State Univ., Northridge. Northridge, CA, USA. 1992. CT Proceedings of the Seventh Annual Conference 'Technology and Persons with Disabilities'. Los Angeles, CA, USA. pp. 359-65. Office Disabled Student Services. 18-21 March 1992. YR 1992. AB In the past five or six years (1986-92), developers have carried virtual reality (VR) technology to the state where potential users can visualize applications for their own special needs. Applications for VR will include: communication, education and training; design, recreation and entertainment; and teleoperation. The purpose of the article is to identify promising matches between VR technology and the special needs of people with disabilities within the framework of these applications. VR technology is still in a very early stage of development, but we can expect to see many of the following developments during the coming years: reduction of system delays; inclusion of tactile and force feedback capabilities; use of speech and other input devices; improvement in visual display resolution; and mobility. 73 AN 4666320. AU Apostolos-M-K. Zak-H. Das-H. Schenker-P. IN Univ. of Southern California, Sch. of Theatre, Los Angeles, CA, USA. TI Multisensory feedback in advanced teleoperations: benefits of auditory cues (in simulated satellite repair task). SO Proceedings of the SPIE - The International Society for Optical Engineering. vol.1828. pp. 98-105. 1992. CT Sensor Fusion V. Boston, MA, USA. SPIE. 15-17 Nov. 1992. YR 1992. RN CCCC: 0 8194 1029 2/92/$4.00. AB The authors an experiment that demonstrated the value of auditory cues in teleoperation as part of a simulated Solar Maximum Satellite Repair (SMSR). The experiment was designed to examine a specific teleoperation task of unbolting an electrical connector screw based on the apparent significance of auditory signals. In addition to the visual cues available from a pair of stereoscopic cameras and contact force feedback cues from the operator's manual hand controller, the operator is given an amplified microphonic task presentation. In general, sounds within the robot workspace are not heard in the operator control room. Six subjects participated in the experiment which examined the performance benefits of vision, force, and sound feedback. The data infers that audio cues can make a significant difference in task completion time. 74 AN 4666222. AU Noll-A-M. IN Annenburg Sch. for Commun., Univ. of Southern California, Los Angeles, CA, USA. TI The beginnings of computer art in the United States: a memoir. SO Leonardo. vol.27, no.1. pp. 39-44. 1994. YR 1994. RN CCCC: 0024-094X/94/$3.00. AB Three decades ago, such terms as computer art, virtual reality and computer animation had not yet entered our vocabulary. This was a time for the experimentation and innovation that produced today's industry of computer art and animation, along with new media for creative experiences with computers. The author has used digital computers in a variety of the visual arts, including still images, stereoscopic images, computer holography, three-dimensional animation, four-dimensional animation, interactive stereoscopic displays and input devices and, ultimately, three-dimensional force-feedback-the latter becoming a major component of today's virtual reality. This research and experimentation in computer art was performed during the 1960s. In this article the author reminisces and describes his early work. 75 AN 4666146. AU Akamatsu-M. Sato-S. IN Nat. Inst. of Biosci. & Human-Technol., Agency of Ind. Sci. & Technol., Tsukuba, Japan. TI A multi-modal mouse with tactile and force feedback. SO International Journal of Human-Computer Studies. vol.40, no.3. pp. 443-53. March 1994. YR 1994. RN CCCC: 1071-5819/94/030443+12$08.00/0. AB We have developed a mouse with tactile and force feedback. Tactile information is provided to the operator by a small pin which projects slightly through the mouse button when pulsed. Force information is provided by an electromagnet inside the mouse in conjunction with an iron mouse pad. Tactile and force feedback are controlled by software linked to the visual information of targets on the visual display. In an empirical evaluation using a target selection task, the addition of tactile and force feedback shortened the response time and widened the effective area of targets. Design issues for interactive systems are discussed. 76 AN 4663789. AU Youcef-Toumi-K. Gutz-D-A. IN Dept. of Mech. Eng., MIT, Cambridge, MA, USA. TI Impact and force control: modeling and experiments. SO Transactions of the ASME. Journal of Dynamic Systems, Measurement and Control. vol.116, no.1. pp. 89-98. March 1994. YR 1994. RN CCCC: 0022-0434/94/$3.00. AB Robot manipulators and drive systems can experience instability or poor control performance after impacting with an environment. This paper presents an analytical model for impact which is experimentally validated step-by-step. Extensive simulations and experiments are conducted to explain impact phenomena for the case of a force feedback control of a drive system. The results are based on an energy method and presented concisely in dimensionless form. To this end, a small number of dimensionless groups are used to characterize the impact behavior through simulations and tests. The study shows that an integral force compensation with a velocity feedback improves force tracking and reject impacts. It is also revealed that impact response can be tuned by selecting a favorable dimensionless ratio of force to approach velocity. 77 AN 4656421. AU Sukhan-Lee. Hahk-Sung-Lee. IN Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA. TI Modeling, design, and evaluation of advanced teleoperator control systems with short time delay. SO IEEE Transactions on Robotics and Automation. vol.9, no.5. pp. 607-23. Oct. 1993. YR 1993. RN CCCC: 1042-296X/93/$03.00. AB A real-time teleoperator control system designed to achieve desired performance and robustness under shared compliance control and short time delays of up to a few seconds is evaluated. In the design, telemonitoring force feedback is introduced as a new form of kinesthetic coupling; dynamic characteristics of the master and slave arms are actively modified based on generalized impedance control according to local design criteria; the human dynamics involved in generating a control command based on visual and force stimuli are incorporated into the controller design; and to balance the robustness/performance trade-off, system performance is optimized subject to a known maximum time delay. Simulation results suggest that the system is superior to conventional systems in terms of performance and robustness under short time delays and human control errors. Experimental evidence is presented to supports the advantages of the proposed telemonitoring force feedback. An experimental method for further validating the human dynamic model is described. 78 AN 4643297. AU Wilfinger-L-S. Wen-J-T. Murphy-S-H. IN Dept. of Electr., Comput., & Syst. Eng., Rensselaer Polytech. Inst., Troy, NY, USA. TI Integral force control with robustness enhancement. SO IEEE Control Systems Magazine. vol.14, no.1. pp. 31-40. Feb. 1994. YR 1994. RN CCCC: 0272-1708/94/$04.00. AB For robotic tasks involving contact between the robot end effector and the environment, force feedback is frequently used to maintain the required force of interaction. Among the many force control strategies proposed in the literature, integral force feedback has been found to be the most desirable algorithm due to its robustness with respect to the measurement time delay and its removal of steady state force error. However, there has not been any serious investigation of the controller performance under large force disturbances. We have experimentally observed that large force disturbances can cause bouncing instability of a nominally stable force control system. Motivated by this observation, we augment the standard integral force controller with three robustness enhancements: integral error scaling, force set-point scheduling, and integral windup saturation. Extensive experimentation on surfaces with different stiffness has shown the dramatic improvement of the modified controller. 79 AN 4641993. AU Bencsik-A. Rudas-I-L. Edited by: Zurawski-R. Dillon-T-S. IN Banki Donat Polytech., Budapest, Hungary. TI Adaptive control of force constrained robot manipulators using master-slave systems. SO Published by: CRL Publishing. Aldershot, UK. 1992. CT IEEE International Workshop on Emerging Technologies and Factory Automation - Technology for the Intelligent Factory - Proceedings (IEEE Cat. No.92TH0500-9). Melbourne, Vic., Australia. pp. 619-23. IEEE. Swinburne Inst. Technol. La Trobe Univ. 11-14 Aug. 1992. YR 1992. AB The authors describe the development of master control arms at their institution. In the late 1980s a hydraulic force-feedback master arm was developed and connected to an ATR HD 500 (Daido) type industrial robot. Based on this result a universal master arm which is kinematically independent of the slave manipulator is under development. The results of these projects are summarized. 80 AN 4637938. AU Diner-D-B. TI Monocular TV vs stereo TV for solar maximum satellite repair subtasks. SO Proceedings of the SPIE - The International Society for Optical Engineering. vol.2057. pp. 325-36. 1993. CT Telemanipulator Technology and Space Telerobotics. Boston, MA, USA. SPIE. 7-9 Sept. 1993. YR 1993. RN CCCC: 0 8194 1322 4/93/$6.00. AB Several operators performed two solar maximum repair subtasks while viewing the workspace with either three monocular (nonstereo) black and white TV cameras or with one pair of stereo black and white TV cameras. For the monocular TV viewing, the three camera views were presented on three TV monitors, and a second operator controlled the pan, tilt and zoom lens power of two of the cameras. For the stereo TV viewing, neither pan, tilt, nor zoom adjustments were allowed, and no second operator was present. Operators were instructed to perform the subtasks as quickly as possible. In all cases, operators completed the tasks more quickly with stereo TV viewing than with multiple monocular TV viewing. Operators reported the learning of the subtasks to be easier with stereo viewing, and reported the most difficult aspect of learning with monocular viewing to be learning which monitor to observe during the various phases of the subtasks. End-effector force and torque feedback was applied to the hand controller, and force and torque data was collected during all experimental runs. However, for the sub-task examined in this paper, no clear relationship between the force/torque data and operator performance could be found. 81 AN 4632242. AU Anderson-R-J. IN Sandia Nat. Labs., Intelligent Machine Syst. Div., Albuquerque, NM, USA. TI Teleoperation with virtual force feedback. SO Proceedings of the SPIE - The International Society for Optical Engineering. vol.2057. pp. 32-9. 1993. CT Telemanipulator Technology and Space Telerobotics. Boston, MA, USA. SPIE. 7-9 Sept. 1993. YR 1993. RN CCCC: 0 8194 1322 4/93/$6.00. AB We describe an algorithm for generating virtual forces in a bilateral teleoperator system. The virtual forces are generated from a world model and are used to provide real-time obstacle avoidance and guidance capabilities. The algorithm requires that the slave's tool and every object in the environment be decomposed into convex polyhedral primitives. Intrusion distance and extraction vectors are then derived at every time step by applying Gilbert's polyhedra distance algorithm, which has been adapted for the task. This information is then used to determine the compression and location of nonlinear virtual spring-dampers whose total force is summed and applied to the manipulator/teleoperator system. Experimental results validate the whole approach, showing that it is possible to compute the algorithm and generate realistic, useful pseudo forces for a bilateral teleoperator system using standard VME bus hardware. 82 AN 4632158. AU Spanos-J. Rahman-Z. von-Flotow-A. IN Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA. TI Active vibration isolation on an experimental flexible structure. SO Proceedings of the SPIE - The International Society for Optical Engineering. vol.1917, no.2. pp. 674-80. 1993. CT Smart Structures and Materials 1993. Smart Structures and Intelligent Systems. Albuquerque, NM, USA. SPIE. 1-4 Feb. 1993. YR 1993. RN CCCC: 0 8194 1150 7/93/$6.00. AB The authors describe experimental research in the area of active vibration isolation. The objective of the research is to quantitatively assess the performance gained by augmenting a passive isolator with an active stage. Vibration isolation experiments were carried out on a flexible structure utilizing a proof-mass shaker as the disturbance source and a newly developed active member as the isolator. Broad band force feedback control demonstrated more than 20 dB reduction in force transmissibility over passive isolation alone. The broad band controller was augmented with notch filters which resulted in reducing force transmissibility by 40 dB over the passive stage in select narrow bands. 83 AN 4625231. AU Merrill-R. IN Lawrence Livermore Nat. Lab., CA, USA. TI Application of an interactive controlled gantry robot in a glove box environment. SO Published by: Robotic Ind. Assoc. Ann Arbor, MI, USA. 1993. CT Proceeding of the International Robots and Vision Automation Conference. Detroit, MI, USA. pp. 6/29. Robotic Ind. Assoc. Autom. Imaging Assoc. Nat. Service Robot Assoc. et al. 5-8 April 1993. YR 1993. AB In order to reduce operator radiation exposure in hazardous operations, LLNL is developing a robotics system which can be utilized in a glove box environment. The system uses an IBM developed gantry mounted seven axis robot with modifications to incorporate force feedback, vision, and interactive control. This robot can be used in both an autonomous mode for routine repetitive tasks or in a real time mode for off-normal tasks which require intelligent human interaction. 84 AN 4613581. AU Purnell-G. Maddock-N. Khodabandehloo-K. IN Manuf. & Autom. Lab., Bristol Univ., UK. TI Robotic deboning: a fundamental approach to engineering a system. SO Published by: EC2. Nanterre, France. 1993. CT AIFA Conference. Artificial Intelligence for Agriculture and Food. Equipment and Process Control Proceedings. Nimes, France. pp. 117-25. 27-29 Oct. 1993. YR 1993. AB Deboning meat is not a simple task. The task requires a high degree of manual dexterity and considerable knowledge and experience. The product itself also presents problems; carcasses are variable in size and shape, and possess non-rigid, temperature influenced properties. For these reasons it is a particularly challenging problem for robotic technology. The production of a robot butcher would not only be a creditable technical achievement, but could also improve meat quality and remove the human from a potentially hazardous environment. This paper gives a summary of the three and a half years' progress made at the University of Bristol towards an automated beef deboning system. In the proposed system each meat section is appraised visually and compared to a database of previous experience. If a match is found, previous cutting information is used to make the deboning cut. However, if no match is found, cut end points are estimated by the vision system and the robot determines its own deboning path using force feedback from the knife. An experimental system operating in 2D on a section of beef has been constructed and has been used to demonstrate the deboning system concept. 85 AN 4602338. AU Richard-P. Burdea-G. Coiffet-P. IN Lab. de Robotique de Paris, Paris 6 Univ., France. TI Human performances in tasks involving virtual objects with force feedback. SO Published by: EC2. Paris, France. 1993. CT Informatique '93. 2nd International Conference on Interface to Real and Virtual Worlds. Proceedings and Exhibition Catalogue. Montpellier, France. pp. 229-38. 22-26 March 1993. YR 1993. AB This paper analyses human performance in tasks involving interactions with virtual objects. Six tests were performed using the 'Rutgers Portable Dextrous Master with Force Feedback' (PDMFF). This master gives force feedback to multiple fingers of the DataGlove. Three virtual objects with different characteristics were used: a ball, a spring and a soda-can. Results show that the learning time was reduced by 50% when virtual force feedback was used. Measured by occurrence of unwanted plastic deformation of the soda-can, the dexterity was increased by 50% due to force feedback. 86 AN 4602319. TI Informatique '93. 2nd International Conference on Interface to Real and Virtual Worlds. Proceedings and Exhibition Catalogue. SO Published by: EC2. Paris, France. 536 pp. 1993. CT Informatique '93. 2nd International Conference on Interface to Real and Virtual Worlds. Proceedings and Exhibition Catalogue. Montpellier, France. 22-26 March 1993. YR 1993. AB The following topics were dealt with: vision and image processing; multimodal interaction; virtual reality tools; natural language processing; virtual reality applications; gestural command; force feedback; database interfaces; hypertext; entertainment; speech processing; office automation; CAD and groupware. 87 AN 4596349. AU Vince-J. IN Hughes Rediffusion Simulation, Crawley, UK. TI VR impacts in flight simulation. SO Published by: Meckler. London, UK. 1993. CT VR93 Virtual Reality International 93. Proceedings of the Third Annual Conference on Virtual Reality. London, UK. pp. 106-10. Meckler. 6-7 April 1993. YR 1993. AB Features such as immersion, real-time interaction, 3D graphics and force-feedback are well-known system concepts, but only recently have they been associated with low-cost VR systems. However, they have been used in flight simulation for over a decade, and this paper describes their use. 88 AN 4586456. AU Figueiredo-M. Bohm-K. Teixeira-J. IN Dept. de Matematica, Coimbra Univ., Portugal. TI Advanced interaction techniques in virtual environments. SO Computers & Graphics. vol.17, no.6. pp. 655-61. Nov.-Dec. 1993. YR 1993. RN CCCC: 0097-8493/93/$6.00+.00. AB Fundamental to much of the virtual reality work is, in addition to high-level 3D graphical and multimedia scenes, research on advanced methods of interaction. The "visitor" of such virtual worlds must be able to act and behave intuitively, as he would in everyday situations, as well as receive expectable natural behaviour presented as feedback from the objects in the environment, in a way that he/she has the feeling of direct interaction with his/her application. We present several techniques to enrich the naturalness and enhance the user involvement in the virtual environment. We present how the user is enabled to grab objects without using any specific and elaborate hand gesture, which is more intuitive and close to the way humans are used to do. We also introduce a technique that makes it possible For the user to surround objects without any force-feedback interaction device. This technique allows the user to surround or "walk" with the virtual hand on the object's surface and look for the best position to grab it. 89 AN 4582531. AU Wang-D. McClamroch-N-H. IN Sch. of Electr. & Electron. Eng., Nanyang Technol. Univ., Singapore. TI Position and force control for constrained manipulator motion: Lyapunov's direct method. SO IEEE Transactions on Robotics and Automation. vol.9, no.3. pp. 308-13. June 1993. YR 1993. RN CCCC: 1042-296X/93/93/$3.00. AB A design procedure for simultaneous position and force control is developed, using Lyapunov's direct method, for manipulators in contact with a rigid environment that can be described by holonomic constraints. Many manipulators that interact with their environment require taking into account the effects of these constraints in the control design. The forces of constraint play a critical role in constrained motion and are, along with displacements and velocities, to be regulated at specified values. Lyapunov's direct method is used to develop a class of position and force feedback controllers. The conditions for gain selection demonstrate the importance of the constraints. Force feedback has been shown not to be mandatory for closed-loop stabilization, but it is useful in improving certain closed-loop robustness properties. 90 AN 4577312. AU Milanesi-S. Rovetta-A. Sala-R. Togno-A. Wen-X. IN Dept. of Mech., Politecnico of Milano, Italy. TI Utilization of stepping motors in the realization of a prototype of perceptive glove with feedback force for telerobotics. SO Published by: IEEE. New York, NY, USA. 1993. CT ISIE'93 - Budapest. IEEE International Symposium on Industrial Electronics. Conference Proceedings (Cat.No.93TH0540-5). Budapest, Hungary. pp. 634-7. IEEE. EPRI. Hungarian Electrotech. Assoc. Hungarian Acad. Sci. et al. 1-3 June 1993. YR 1993. RN CCCC: 0 7803 1227 9/93/$3.00. AB Force feedback is a basic element in realizations for telemanipulation and virtual reality. In telemanipulation, tactile but especially force information permits the remote operator to carry out efficiently operations which would otherwise be difficult to perform; nevertheless it permits a better simulation and interaction of virtual environment in the case of virtual reality. A system for grasping objects was projected and realized in a robotics laboratory. The operator wearing a glove drives a mechanical hand, having a force sensor on his own hand. This increases the performance of the telemanipulation system. The whole project is explained with particular attention to the control system of stepping motors used for force feedback. 91 AN 4554945. AU Lee-S. Lee-H-S. IN Univ. of Southern California, Los Angeles, CA, USA. TI Advanced telemanipulation under time delay. SO Proceedings of the SPIE - The International Society for Optical Engineering. vol.1833. pp. 92-101. 1993. CT Telemanipulator technology. Boston, MA, USA. SPIE. 15-16 Nov. 1992. YR 1993. RN CCCC: 0 8194 1034 9/93/$4.00. AB An advanced teleoperator control system is designed based on the paradigm of telemonitoring and the Smith principle. By incorporating the model of human dynamics reacting to visual and force feedbacks into the control loop, a systematic and analytic way of obtaining an optimal teleoperator controller supporting operator's case of control as well as of designing an optimal human/machine interface is established. The designed teleoperator control system also provides a proper coordination between the human operator and manipulators under shared control through monitoring force feedback. The Smith principle is used to construct an optimal teleoperator control system under time delay, which allows not only to interpret the role of simulators in teleprogramming under time delay but also to provide an analytic result of what kind of sensory information is required and how the sensory information is fed back to the human operator. Simulation results are shown. 92 AN 4548774. AU Massimino-M. Sheridan-T. IN Space Station Div., McDonnell Douglas Space Syst. Co., Houston, TX, USA. TI Using auditory and tactile displays for force feedback. SO Proceedings of the SPIE - The International Society for Optical Engineering. vol.1833. pp. 325-36. 1993. CT Telemanipulator technology. Boston, MA, USA. SPIE. 15-16 Nov. 1992. YR 1993. RN CCCC: 0 8194 1034 9/93/$4.00. AB The use of tactile and auditory displays to present force feedback is discussed. These displays can provide the human operator with force information without some of the disadvantages of force reflection. The design of the displays are explained, as well as an experimental study on the effectiveness of the displays for remote manipulation tasks. These displays compared favorably to traditional force reflection for basic force perception tests, and improved the human operator's sensitivity for detecting small forces. With a time delay, the displays improved operator performance for peg-in-hole tasks without instabilities. They also improved performance during degraded visual conditions. The benefits of using such displays for telemanipulation tasks is discussed, as well as potential applications and future research. 93 AN 4548762. AU Howe-R-D. Kontarinis-D. IN Div. of Appl. Sci., Harvard Univ., Cambridge, MA, USA. TI Task performance with a dextrous teleoperated hand system. SO Proceedings of the SPIE - The International Society for Optical Engineering. vol.1833. pp. 199-207. 1993. CT Telemanipulator technology. Boston, MA, USA. SPIE. 15-16 Nov. 1992. YR 1993. RN CCCC: 0 8194 1034 9/93/$4.00. AB Examines the role of force bandwidth in performance of close-tolerance peg-in-hole insertion. The experiments use a two fingered teleoperated hand system with finger-level force feedback. Low-pass filters are used to vary the frequency content of the force feedback signal. Task completion times and error rates decrease as force reflection bandwidth increases. Most of the benefit appears between 2 and 8 Hz bandwidth, although some improvement is seen at 32 Hz, the highest frequency examined. These experiments also indicate that even low bandwidth force feedback improves the operator's ability to moderate task forces. However, force feedback does not enable the operator to minimize the grasp force, since this requires information about the friction at the contact between the grasped object and the slave finger tip. 94 AN 4529180. AU Cai-Hegao. Yang-Ting. Zhao-Jie. IN Robot Res. Inst., Harbin Inst. of Technol., China. TI The implementation of active/passive coordinated manipulation in precision assembly based on force-feedback. SO Published by: IEEE. New York, NY, USA. 1992. CT Proceedings of the IEEE International Symposium on Industrial Electronics (Cat. No.92TH0371-5). Xian, China. pp. 347-51 vol.1. IEEE. Soc. Instrum. & Control Eng. Japan. et al. 25-29 May 1992. YR 1992. AB The authors present a new idea on assembly principle and a newly developed robotic assembly system based on force feedback, which employs a specially designed active/passive micro manipulator (APMM) to combine both active accommodation and passive compliance function in one. The test setup consists of a PUMA 562 robot, an APMM and its driver unit, a 6 dimensional force/torque sensor and its controller, an IBM-PC computer and specially designed interfaces. During assembly, the PUMA robot takes care of coarse positioning and insert motion, while the APMM, which is mounted on the end of PUMA robot, executes fine position adjustment by optimal cooperation of active and passive mating based upon force feedback. The system can carry out assembly operation along arbitrary direction within several seconds even under the condition of unchamfered parts. 95 AN 4529174. AU Xu-Chen. Shi-Weixiang. Zhang-Jinghui. IN Xi'an Jiaotong Univ., China. TI An investigation of the effect of distributed structure flexibility on behavior of single-link manipulator force-feedback control system. SO Published by: IEEE. New York, NY, USA. 1992. CT Proceedings of the IEEE International Symposium on Industrial Electronics (Cat. No.92TH0371-5). Xian, China. pp. 320-3 vol.1. IEEE. Soc. Instrum. & Control Eng. Japan. et al. 25-29 May 1992. YR 1992. AB In previous research, the authors obtained some high accuracy dynamic models for flexible manipulators. On the basis of the above dynamic models, some further research was made, which is going to be reported in this paper, to investigate the effect of distributed structure flexibility on behavior of a single-link manipulator force-feedback control system. 96 AN 4522039. AU Jimenez-S. Luciani-A. Laugier-C. IN ACROE-IMAG/LIFIA, Grenoble, France. TI Simulating physical interactions between an articulated mobile vehicle and a terrain. SO Robotics and Autonomous Systems. vol.11, no.2. pp. 97-107. Sept. 1993. YR 1993. RN CCCC: 0921-8890/93/$06.00. AB This paper deals with the problem of planning the motion of a complex land vehicle moving in a natural environment. The contribution presented is a motion generator which predicts the dynamic behaviour of the vehicle when executing a given nominal motion plan. This plan is expressed in terms of a channel that must be followed and of a set of intermediate subgoals that must be reached. Solving this motion generation problem requires to explicitly reason about the geometric and the physical aspects of the movements that the vehicle has to execute. This is done by using two basic constructions derived from the concept of physical model: the 'generalized obstacles' are used to physically guide the movements of the vehicle using an explicit model of the vehicle-terrain interactions, and the 'physical targets' are used to map the strategic information onto a physical representation of the world and to introduce the force feedback gestural control. 97 AN 4508638. AU Bergamasco-M. IN ARTS Lab., Pisa Univ., Italy. TI Design of hand force feedback systems for glove-like advanced interfaces. SO Published by: IEEE. New York, NY, USA. 1992. CT Proceedings. IEEE International Workshop on Robot and Human Communication (Cat. No.92TH0469-7). Tokyo, Japan. pp. 286-93. IEEE. Soc. Instrum. Control Eng. Robotics Soc. Japan. et al. 1-3 Sept. 1992. YR 1992. RN CCCC: 0 7803 0753 4/92/$3.00. AB In this paper the general concept of force feedback on the operator's hands is considered by analyzing the contact forces occurring during general exploratory and manipulative procedures performed by both the robot and virtual hands. The design aspect of hand force feedback systems for glove-like advanced interfaces is based on the specific spectrum of forces required to reproduce on the human hand. 98 AN 4508050. AU Brienza-D-M. Chung-K-C. Brubaker-C-E. Kwiatkowski-R-J. IN Pittsburgh Univ., PA, USA. TI Design of a computer-controlled seating surface for research applications. SO IEEE Transactions on Rehabilitation Engineering. vol.1, no.1. pp. 63-6. March 1993. YR 1993. RN CCCC: 1063-6528/93/$03.00. AB The design of a system to facilitate investigations of the loading of the human body on a seat surface and the ongoing evaluation of a prototype system are presented. Knowledge and understanding of the effect of support surface shape on load distribution at the body and seat interface are vital components of an automated seat contour design and fabrication system. The need for a research tool that allows for control of surface shape with simultaneous measurement of the interface forces is of considerable importance to current research in the area of custom and specialized seating. The computer-aided seating system (CASS) presented allows for development of surface control algorithms based on force feedback that are not possible using currently available contour sensing and evaluation devices. Additionally, the contour-controlled force feedback system will facilitate the study of tissue distortion at the loaded seat interface. Such information about how the body distorts under load can be directly applied to passive custom seating systems, assist in clinical seat contour design and benefit designs on noncustom wheelchair cushions. The specification, design and testing of a prototype of the CASS is described. 99 AN 4489592. AU Mansfield-P-K. IN Intelligent Auto. Syst. Inc., Cambridge, MA, USA. TI Robotic real-time adaptive grasping. SO Robotics World. vol.11, no.2. pp. 18-20. Summer 1993. YR 1993. AB The objective of adaptive grasping is to use sensory feedback to guide and plan the strategy employed when grasping an unfamiliar or unmodeled object. Using force feedback to modulate actuator effort for the purpose of controlling end-effector force applied to a touched object and tactile sampling to measure contact locations can provide a robotic grasping system that is simultaneously adaptive, powerful and gentle. The applications for this technology are very broad. Adaptive grasping has been demonstrated on an autonomous robot developed by Intelligent Automation Systems Inc. for NASA's Johnson Space Center. 100 AN 4488769. AU Engstrom-J-W. Goldmann-L-H. Truitt-R-W. IN Westinghouse Hanford Co., Richland, WA, USA. TI A facility to remotely assemble radioisotope thermoelectric generators. SO AIP Conference Proceedings. no.271, pt.2. pp. 1133-7. 1993. CT 10th Symposium on Space Nuclear Power and Propulsion. Albuquerque, NM, USA. Inst. Space Nucl. Power Studies. NASA. et al. 10-14 Jan. 1993. YR 1993. RN CCCC: 0094-243X/93/$2.00. AB Radio isotope Thermoelectric Generators (RTGs) are electrical power sources that use heat from decaying radioisotopes to directly generate electrical power. The RTG assembly process is performed in an inert atmosphere inside a large glovebox, which is surrounded by radiation shielding to reduce exposure to neutron and gamma radiation from the radioisotope heat source. In the past, allowable dose rate limits have allowed direct, manual assembly methods; however, current does rate limits require a thicker radiation shielding that makes direct, manual assembly infeasible. To minimize RTG assembly process modifications, telerobotic systems are being investigated to perform remote assembly tasks. Telerobotic systems duplicate human arm motion and incorporate force feedback sensitivity to handle objects and tools in a human-like manner. A telerobotic system with two arms and a three-dimensional (3-D) vision system can be used to perform remote RTG assembly tasks inside gloveboxes and cells using unmodified, normal hand tools. 101 AN 4482500. AU Noma-H. Iwata-H. IN Inst. of Eng. & Mech., Tsukuba Univ., Japan. TI Development of a 9 d.o.f. force display and its performance evaluation. SO Transactions of the Society of Instrument and Control Engineers. vol.29, no.4. pp. 455-60. April 1993. YR 1993. AB Artificial reality is expected to form a new configuration of human-computer interaction. This paper describes a method of implementation of the force feedback device (force display) and its performance evaluation. The device presents a desktop virtual space in which a computer generates visual and tactile sensation. An operator wears a 9 d.o.f. master manipulator on the right hand and puts a head mounted display on. The operator can touch and hold virtual objects in virtual space. Evaluating system performance, behavior and reaction time for operating a virtual toggle switch are examined. Distance and size of the toggle switch were considered as indices of difficulty of the operation. From the results, it was suggested that an operation with tactile sense has advantage on recognizability of switch. 102 AN 4480070. AU Bryfogle-M-D. Nguyen-C-C. Antrazi-S-S. Chiou-P-C. IN Science Applications Inter. Corp., McLean, VA, USA. TI Kinematics and control of a fully parallel force-reflecting hand controller for manipulator teleoperation. SO Journal of Robotic Systems. vol.10, no.5. pp. 745-66. July 1993. YR 1993. RN CCCC: 0741-2223/93/050745-022. AB Force feedback can enhance the efficiency of a teleoperation system by providing the operator with a sense of feel of the forces and torques arising from the interaction of the slave manipulator with the remote environment. The article addresses the kinematic analysis and control of a parallel force-reflecting hand controller (PFORHC) whose design and implementation are based on a fully parallel mechanism. Kinematic analysis on the PFORHC is performed and results in a closed-form solution for the inverse kinematics. The forward kinematics is solved by Newton-Raphson's method. A fixed-gain PD control scheme is developed for force feedback control. Experiments are conducted to study the performance of the force-reflecting capability of the PFORHC. Experimental results show that the force control scheme utilizing a handgrip force sensor provides smaller steady-state errors as compared to the case utilizing no handgrip force sensor. 103 AN 4477513. AU Weijie-Yun. Howe-R-T. IN BEI Electron., Inc., Sylmar, CA, USA. TI Sigma - Delta modulator interfacing with silicon microsensors. SO Sensors. vol.10, no.5. pp. 11-14, 16, 18. May 1993. YR 1993. AB Sigma-delta ( Sigma - Delta ) modulation has become a popular design technique for data conversion circuits. In Sigma - Delta modulators, the input signal is sampled at a frequency much higher than its Nyquist rate, so that adjacent samples are correlated with each other. The sampled data are integrated, digitized by a coarse quantizer at the output, fed back, and subtracted from the next input samples. The quantization noise is then shaped such that it is significantly suppressed in the baseband and 'pushed' to high frequencies. Sigma - Delta modulation techniques have many applications in sensor and actuator systems. They have inherent advantages for interfacing with the digital control environment. The research in force-balance accelerometers indicates that for electrostatic force-feedback systems, the Sigma - Delta modulator offers an approach for incorporating the ADC in the sensor front-end. 104 AN 4463073. AU Stokic-D-M. Vukobratovic-M-K. Surdilovic-D-M. IN Inst. M. Pupin, Beograd, Yugoslavia. TI An adaptive hybrid control scheme for manipulation robots with implicit force control. SO Published by: IEEE. New York, NY, USA. 1991. CT 91 ICAR. Fifth International Conference on Advanced Robotics. Robots in Unstructured Environments (Cat. No.91TH0376-4). Pisa, Italy. pp. 1505-8 vol.2. CNR. CPR. Univ. Genoa. ENEA. IBM SEMEA. Univ. Pisa. IEEE et al. 19-22 June 1991. YR 1991. RN CCCC: 7803-0078/91/0600-1505$01.00. AB An adaptive hybrid position/force control scheme for manipulation robots in constrained motion tasks is considered in the paper. The proposed control scheme is based on implicit force control, although it includes an explicit force feedback loop too. The scheme includes a block for identification of contact force parameters, as well as a block for tuning of feedback gains according to the identified parameters. The scheme is briefly described and the simulation tests are presented. 105 AN 4463030. AU Marbot-P-H. Hannaford-B. IN Dept. of Electr. Eng., Washington Univ., Seattle, WA, USA. TI Mini direct drive robot arm for biomedical application. SO Published by: IEEE. New York, NY, USA. 1991. CT 91 ICAR. Fifth International Conference on Advanced Robotics. Robots in Unstructured Environments (Cat. No.91TH0376-4). Pisa, Italy. pp. 859-64 vol.1. CNR. CPR. Univ. Genoa. ENEA. IBM SEMEA. Univ. Pisa. IEEE et al. 19-22 June 1991. YR 1991. RN CCCC: 7803-0078/91/0600-0859$01.00. AB The potential of electromagnetic actuation in a very small machine has been investigated. It has been compared to the newer technology of electrostatic micro-machines. Considerations on energy density, scaling capability, heat dissipation and actual geometry of a design have lead the authors to the conclusion that electromagnetic actuators are also competitive in the submillimeter range. The authors give a description of their 4 degree of freedom direct drive force feedback mini robot. It uses winchester disk drive technology, which is compact, powerful, clean and getting smaller, year after year. This robot could be the prototype of a family of mini-robots adapted to micro-surgery, biology and clean-room environment. 106 AN 4461638. AU Bay-J-S. Hemami-H. IN Bradley Dept. of Electr. Eng., Virginia Polytech. Inst. & State Univ., Blacksburg, VA, USA. TI Localization of hybrid controllers for manipulation on unknown constraints. SO Journal of Intelligent and Robotic Systems: Theory and Applications. vol.7, no.3. pp. 301-20. June 1993. YR 1993. AB A robotic control problem is proposed in which a six degree of freedom manipulator is to explore the surface of an object which is a priori unknown to the controller. Choice of an exploration strategy is discussed. The exploration strategy developed uses the maximal freedom of choice allowed under the restrictions of the problem. In particular, it is shown that any admissible reference trajectory can be used, provided it lies in a two-dimensional manifold which maps continuously into the surface. The inverse kinematic velocity problem is then solved using pseudo-inverses which fully exploit the redundancy of the system. The controller used as an example uses computed torque for linearization and compliant motion theory for movement along the desired path. The solution to the inverse kinematic problem together with the online generation of 'selection-mappings' constitute a hybrid force/velocity controller. Successful exploration is shown to depend heavily on reliable force control, so PI force feedback is also proposed. Simulation and experimental results demonstrate the effectiveness of the overall design. 107 AN 4459159. AU Fukuda-T. Fujiyoshi-M. Kosuge-K. Arai-F. IN Dept. of Mech. Eng., Nagoya Univ., Japan. TI Design and dextrous control of micromanipulator with 6 D.O.F. SO Published by: IEEE. New York, NY, USA. 1991. CT 91 ICAR. Fifth International Conference on Advanced Robotics. Robots in Unstructured Environments (Cat. No.91TH0376-4). Pisa, Italy. pp. 343-8 vol.1. CNR. CPR. Univ. Genoa. ENEA. IBM SEMEA. Univ. Pisa. IEEE et al. 19-22 June 1991. YR 1991. RN CCCC: 7803-0078/91/0600-0343$01.00. AB A six-degrees-of-freedom micromanipulator using PZT actuators has been designed and tested. The main features are that: (1) the micromanipulator is very small and light: (2) it has a position and force feedback system, and can control desired poses and forces; (3) since the manipulator has 6 d.o.f., the tip of this manipulator can move along three axes, and can also rotate along each axis; (4) a fuzzylike variable gain feedback control system is employed, and hence the system performs better than the fixed gain feedback system. These technical merits will make it possible to operate this dextrous micromanipulator in much more complicated environments under a microscope. 108 AN 4459139. AU Funda-J. Paul-R-P. IN Dept. of Comput. & Inf. Sci., Pennsylvania Univ., Philadelphia, PA, USA. TI Efficient control of a robotic system for time-delayed environments. SO Published by: IEEE. New York, NY, USA. 1991. CT 91 ICAR. Fifth International Conference on Advanced Robotics. Robots in Unstructured Environments (Cat. No.91TH0376-4). Pisa, Italy. pp. 219-24 vol.1. CNR. CPR. Univ. Genoa. ENEA. IBM SEMEA. Univ. Pisa. IEEE et al. 19-22 June 1991. YR 1991. RN CCCC: 7803-0078/91/0600-0219$01.00. AB Addresses the problem of teleoperation in the presence of feedback delays. Delay occurs with Earth-based teleoperation in space and with surface-based teleoperation of untethered submersibles when acoustic communication links are involved. The delay in obtaining position and force feedback from remote slave arms makes direct teleoperation impossible. This paper proposes a new control methodology for time-delayed remote manipulation, teleprogramming, based on a novel combination of computer graphics, virtual reality, and manipulator programming. The teleprogramming methodology allows for continuous and efficient control of remote workcells in the presence of significant feedback delays. An overview of the methodology for a single workcell is presented and experimental results using a prototype laboratory system are reported. 109 AN 4459129. AU Bergamasco-M. De-Micheli-D-M. Parrini-G. Salsedo-F. Marchese-S-S. IN ARTS Lab., Scuola Superiore S. Anna, Pisa, Italy. TI Design considerations for glove-like advanced interfaces. SO Published by: IEEE. New York, NY, USA. 1991. CT 91 ICAR. Fifth International Conference on Advanced Robotics. Robots in Unstructured Environments (Cat. No.91TH0376-4). Pisa, Italy. pp. 162-7 vol.1. CNR. CPR. Univ. Genoa. ENEA. IBM SEMEA. Univ. Pisa. IEEE et al. 19-22 June 1991. YR 1991. RN CCCC: 7803-0078/91/0600-0162$01.00. AB Addresses general aspects associated with the design of glove-like advanced interfaces used for both teleoperation of dexterous robot hands and virtual environments. The function of glove components such as kinesthetic sensors and hand force feedback systems are analyzed. Discrimination between tactile and hand force feedback is outlined. 110 AN 4438139. AU Mertz-J. Marti-O. Mlynek-J. IN Fak. fur Phys., Konstanz Univ., Germany. TI Regulation of a microcantilever response by force feedback. SO Applied Physics Letters. vol.62, no.19. pp. 2344-6. 10 May 1993. YR 1993. RN CCCC: 0003-6951/93/192344-03$06.00. AB A feedback mechanism is used to control the forces incident on a mechanical microcantilever as a function of the monitored cantilever motion. The control is effected by modifying the intensity of an auxiliary laser beam that generates a thermally induced stress. The feedback is designed to reduce the effective resonance quality factor of the cantilever. The resultant regulation of the cantilever motion is shown to improve the measurement dynamics in atomic force microscopy, without significantly degrading the signal to noise ratio. 111 AN 4426029. AU Jimenez-S. Luciani-A. Raoult-O. IN Association pour la Creation et la Recherche sur les Outils d'Expression, Inst. d'Infor. et de Math. Appliquees, Grenoble, France. TI Physical simulation of land vehicles with obstacle avoidance and various terrain interactions. SO Journal of Visualization and Computer Animation. vol.4, no.2. pp. 79-94. April-June 1993. YR 1993. AB Programming the motions of an autonomous planetary robot moving in an hostile and hazardous environment is a complex task which requires both the construction of nominal motion plans and the anticipation as far as possible of the effects of the interactions existing between the vehicle and the terrain. The authors show how physical models and dynamic simulation tools can be used for amending and completing nominal motion plan provided by a classical geometrical path planner. The purpose of the physical modeller-simulator is to anticipate the dynamic behaviour of the vehicle while executing the nominal motion plan. Then the obtained simulation results can be used to assess and optimize the nominal motion plan. The authors outline the physical models that have been used for modelling the different types of vehicle, of terrain and of vehicle-surface interactions. Then they formulate the motion planning problem through the definition of two basic abstract constructions derived from physical model: the concept of generalized obstacle and the concept of physical target. They show with various examples how it is possible, when using this method, to solve the locomotion problem and the obstacle avoidance problem simultaneously and, furthermore, to provide the human operator with a true force feedback gestural control over the simulated robot. 112 AN 4424313. AU Brienza-D-M. Inigo-R-M. Chung-K-C. Brubaker-C-E. IN Dept. of Electr. Eng., Pittsburgh Univ., PA, USA. TI Seat support surface optimization using force feedback. SO IEEE Transactions on Biomedical Engineering. vol.40, no.1. pp. 95-104. Jan. 1993. YR 1993. RN CCCC: 0018-9294/93/$0.300. AB The development, implementation and evaluation of an algorithm designed to find optimal seat support surfaces are presented. The algorithm has been developed and implemented on an active contour measurement device. The device consists of an array of positioning elements equipped with force sensors for feedback. With a patient seated on the array, the algorithm is designed to find a seat contour that optimally satisfies given performance criteria. The performance criteria are based on measured stiffness of the soft tissues. A theoretical development of the algorithm is presented along with the modifications made to the algorithm during implementation. The results from several tests using man-made test bodies and a prototype contour gauge are presented to verify the algorithm's performance. 113 AN 4422509. AU Clark-W-W. Robertshaw-H-H. IN Dept. of Mech. Eng., Pittsburgh Univ., PA, USA. TI Application of adaptive trusses to vibration isolation in flexible structures. SO Published by: American Autom. Control Council. Evanston, IL, USA. 1992. CT Proceedings of the 1992 American Control Conference (IEEE Cat. No.92CH3072-6). Chicago, IL, USA. pp. 2215-19 vol.3. American Autom. Control Council. 24-26 June 1992. YR 1992. AB It is shown through analysis that force feedback can be used to provide complete vibration isolation in two directions. Simulations were carried out to demonstrate the use of two control methods applied to an adaptive truss as an active mount. The first technique was simple force feedback with a gain. This method has the potential to provide excellent vibration isolation performance. It requires no model of the system and no knowledge of the applied disturbance, and is easily implemented in an adaptive truss. Experimental results have shown performance advantages over passive techniques even for small gains. The second technique presented is the LQR method, with disturbance modeling. A method is presented for using the LQR method for vibration isolation with the intention of achieving performance with guaranteed stability and relatively lower loop gains. An accurate system model is required. The method works; however, the performance is not as good as expected. It is believed that the difference in performance is partly due to an increase in active damping which is inadvertently provided by the LQR method. 114 AN 4386775. AU Lin-S-T. Yae-K-H. IN Dept. of Mech. Eng., Iowa Univ., Iowa City, IA, USA. TI Controller design for robot tasks involving free and contact motion. SO Published by: American Autom. Control Council. Evanston, IL, USA. 1992. CT Proceedings of the 1992 American Control Conference (IEEE Cat. No.92CH3072-6). Chicago, IL, USA. pp. 765-70 vol.1. American Autom. Control Council. 24-26 June 1992. YR 1992. AB A controller design strategy is proposed for a task entailing both free and contact motion. Position control is developed in free motion. Using impedance control, force control is then added through the contact force feedback loop. A compensator in this feedback loop helps to reach the target impedance when the end-effector is in contact with the environment. Contact force is assumed to be available from a wrist force sensor. Since the force sensor signal may also contain inertial force, a Kalman filter is used to extract contact force from the signal. The development is illustrated with three examples. 115 AN 4382227. AU Galbiati-L. Raimondi-T. Garetti-P. Costi-G. IN JET Joint Undertaking, Abingdon, UK. TI Control and operational aspects of the Mascot 4 force feedback servomanipulator of JET. SO Published by: IEEE. New York, NY, USA. 1992. CT 14th IEEE/NPSS Symposium. Fusion Engineering. Proceedings (Cat. No.91CH30355-3). San Diego, CA, USA. pp. 563-6 vol.1. IEEE. 30 Sept.-3 Oct. 1991. YR 1992. RN CCCC: 91CH3035-3/$03.00. AB The telemanipulator developed for maintenance of the JET (Joint European Torus) tokamak (Mascot 4) is a microprocessor-controlled unit based on bilateral position servosystems. The main objective of this type of force-feedback servomanipulator is to give the operator, as nearly as possible, the tactile sensations of actually doing the job. Servomanipulator sensitivity, stiffness, time response and low reflected inertia characteristics are achieved by using low-friction AC motors, high-resolution R/D converters, fast sampling time, and short delays in the signal transmissions. There is a 16-bit Z8001 CPU and a servo amplifier for each servo system, and a global CPU with 16+16 I/O for general supervision. For the advanced function an auxiliary CPU with 256 Kb of RAM is used. Communication between master and slave is via a high-speed full duplex serial link at 1 MHz. The digital system has permitted a reduction of the cabling required and the introduction of advanced aids to the operator: teach and repeat, tool weight compensation, and constraint of the trajectory on given planes or lines. 116 AN 4368177. AU Lange-F. Hirzinger-G. IN Inst. of Flight Syst. Dynamics, DLR, Oberpfaffenhofen, Germany. TI Iterative self-improvement of force feedback control in contour tracking. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1992. CT Proceedings. 1992 IEEE International Conference on Robotics And Automation (Cat. No.92CH3140-1). Nice, France. pp. 1399-404 vol.2. IEEE. 12-14 May 1992. YR 1992. RN CCCC: 0 8186 2720 4/92$03.00. AB A very general three-level learning method for self-improvement of the parameters of a force feedback controller is demonstrated in contour tracking tasks. It is assumed that no model is known a priori, either of the robot or of the contour to be tracked. The system identifies such a model, including information about its reliability. The model and estimated noise were used to generate optimal control actions for the sample trajectory. They were then used for estimation of the parameters of the controller. This controller then produces a new trajectory, which in turn could be optimized and trained. Kalman filter techniques were applied in all adaptation levels involved. Learning was possible off-line or online. The model and controller may be based on linear difference equations or include nonlinear mappings as associative or tabular memories or neural networks. It was shown that even for a linear controller substantial improvements could be attained as no assumptions were needed about the bandwidth. 117 AN 4368143. AU Lee-S. Lee-H-S. IN Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA. TI An advanced teleoperator control system: design and evaluation. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1992. CT Proceedings. 1992 IEEE International Conference on Robotics And Automation (Cat. No.92CH3140-1). Nice, France. pp. 859-64 vol.1. IEEE. 12-14 May 1992. YR 1992. RN CCCC: 0 8186 2720 4/92$03.00. AB The design goal of an advanced teleoperator control system is twofold: (1) to allow the operator's manual control to be robust to system nonlinearities such as time delays and operator's control errors, and (2) to support the high performance of teleoperation while reducing the operator's control burden by providing the master and slave arms with desirable dynamic properties and by allowing the slave arm to automatically perform such control tasks as compliance and force control in the form of task sharing. The authors present a novel teleoperator control system achieving the above design goal by taking the following into consideration: the human dynamics involved in generating control command based on visual and force feedback is modeled and incorporated into the controller design and evaluation: the dynamic characteristics of slave and master arms are actively modified in such a way as to implement the desirable dynamic characteristics; and the force feedback is redefined in terms of the combination of opposition and force discrepancies in order to establish the required man/machine dynamic coordination under shared control. The proposed control system with human dynamics in the control loop is simulated and compared with a number of conventional methods in the presence of human control errors and time delays. 118 AN 4362945. AU Kazanzides-P. Zuhars-J. Mittelstadt-B. Taylor-R-H. IN Integrated Surg. Syst., Sacramento, CA, USA. TI Force sensing and control for a surgical robot. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1992. CT Proceedings. 1992 IEEE International Conference on Robotics And Automation (Cat. No.92CH3140-1). Nice, France. pp. 612-17 vol.1. IEEE. 12-14 May 1992. YR 1992. RN CCCC: 0 8186 2720 4/92$03.00. AB The authors describe the use of force feedback in a surgical robot system (ROBODOC). The application initially being addressed is total hip replacement (THR) surgery, where the robot must prepare a cavity in the femur for an artificial implant. In this system, force feedback is used to provide safety, tactile search capabilities, and an improved man-machine interface. Output of the force sensor is monitored by a safety processor, which initiates corrective action if any of several application-defined thresholds are exceeded. The robot is able to locate objects using guarded moves and force control (ball-in-cone strategy). In addition, the force control algorithm provides an intuitive man-machine interface which allows the surgeon to guide the robot by leading its tool to the desired location. An application of force control currently under development is described, where the force feedback is used to modify the cutter feed rate (force controlled velocity). 119 AN 4362439. AU Patton-R. Swern-F. Tricamo-S. van-der-Veen-A. IN Mississippi State Univ., Mississippi State, MS, USA. TI Automated cloth handling using adaptive force feedback. SO Transactions of the ASME. Journal of Dynamic Systems, Measurement and Control. vol.114, no.4. pp. 731-3. Dec. 1992. YR 1992. AB Control loop for the handling of cloth is described and tested. The control loop is an adaptive force feedback controller which both provides correct tension on the cloth and straightens wrinkles in the cloth. The control loop was implemented and tested on a PUMA 560 robot with a LORD 15/50 force/torque sensor mounted on its wrist. Experiments demonstrate the ability of the control loop to straighten the cloth and to exert a specified tension on the cloth. 120 AN 4359484. AU Wang-D. IN Sch. of Electr. & Electron. Eng., Nanyang Technol. Univ., Singapore, Singapore. TI Stability and control of a constrained manipulator. SO Published by: Instn. Eng. Australia. Barton, ACT, Australia. 1992. CT Control 92. Enhancing Australia's Productivity Through Automation, Control and Instrumentation. Preprints of Papers. Perth, WA, USA. pp. 393-401. Inst. Eng. Australia. Process Control Soc. Inst. Instrum. Control, Australia. 2-4 Nov. 1992. YR 1992. AB Stability and control problems for a constrained two link manipulator are analyzed and solved. The contact force with environmental constraint is formulated as part of the potential energy function. The effect of constraint reaction force is shown to be critical to stability of constrained motion. The slope of a straight line constraint is a key factor in the stability and control design. Simple PD controllers are designed for simultaneous regulation of position and contact force on constraint. Feedback control design requires that constraint functions be taken into account in feedback gain selections to guarantee position and force regulations. Contact force feedback is used to improve force response in uncertain environment. 121 AN 4358957. AU Long-G-L. Collins-C-L. IN Mech. & Aerosp. Eng., California Univ., Irvine, CA, USA. TI A pantograph linkage parallel platform master hand controller for force-reflection. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1992. CT Proceedings. 1992 IEEE International Conference on Robotics And Automation (Cat. No.92CH3140-1). Nice, France. pp. 390-5 vol.1. IEEE. 12-14 May 1992. YR 1992. RN CCCC: 0 8186 2720 4/92$03.00. AB The authors discuss the kinematics of a serial/parallel six degree-of-freedom generalized hand controller for teleoperation. A description of the device is presented with equations needed for control of a remote manipulator. The pantograph linkages extend the workspace of traditional platform designs, while the parallel structure provides force regulation at the platform that is well suited for force-feedback to a teleoperator. The generalized teleoperator controller described will be part of a larger telerobotics system comprising a radio-controlled robotic arm module with appropriate end-effectors and a general-purpose supervisory controlled system. The robotic system is planned for remote handling of toxic solid and liquid debris. 122 AN 4340779. AU Stewart-A-M. Parker-J-L. IN Dept. of Appl. Math., Res. Sch. of Phys. Sci. & Eng., Australian Nat. Univ., Canberra, ACT, Australia. TI Force feedback surface force apparatus: principles of operation. SO Review of Scientific Instruments. vol.63, no.12. pp. 5626-33. Dec. 1992. YR 1992. RN CCCC: 0034-6748/92/125626-08$02.00. AB The principles of operation of a force feedback surface force apparatus are described. A magnetic force transducer and a bimorph displacement sensor are connected in a servo loop. The dynamic behavior of the system is analyzed and the effect of eddy currents on the frequency response of the magnetic field is discussed. The apparatus has several advantages over more traditional force measuring techniques. Cantilever instability associated with the measurement of attractive forces is reduced and the apparatus may be used for hydrodynamic measurements. A resonance technique for measuring the spring constant is also described. 123 AN 4336350. AU Brezina-M. Khan-M. IN Dept. of Mech. Eng., Sherbrooke Univ., Que., Canada. TI Some strategies in automated assembly of small rigid parts based on force feedback. SO Published by: Univ. Metz. Metz, France. 1992. CT CARs and FOF. 8th International Conference on CAD/CAM, Robotics and Factories of the Future. Metz, France. pp. 1887-900 vol.2. Int. Soc. Productivity Enhancement. INRIA. Univ. Metz. Univ. Nancy. et al. 17-19 Aug. 1992. YR 1992. AB The paper describes a hybrid system composed of a remote center compliance device and a 6-axes force sensor mounted at a manipulator's wrist. It also describes the algorithms developed for and used in a peg-chamfered hole assembly operation. 124 AN 4330202. AU Zhou-Y. IN Sch. of Electr. Eng., Purdue Univ., West Lafayette, IN, USA. TI Dynamic model and force control for two manipulators handling a pin-jointed object. SO Published by: IEEE. New York, NY, USA. 1991. CT Proceedings of the 30th IEEE Conference on Decision and Control (Cat. No.91CH3076-7). Brighton, UK. pp. 2763-8 vol.3. IEEE. 11-13 Dec. 1991. YR 1991. RN CCCC: CH3076-7/91/0000-2763$01.00. AB A dynamic model for two coordinated robots handling a pin-jointed object system is developed. Both kinematic and dynamic constraints are considered, but dynamic constraints are specifically studied. The dynamic model is obtained bv combining the dynamic model for each manipulator with dynamic constraints. The force/torque acting at the end-effector is formulated by a different approach. With this external force expression, the force control problem can be simplified as torque compensation in joint space. Therefore, the original PID (proportional plus integral plus derivative) joint position control loop of an industrial robot can be preserved. An additional force feedback loop is used for compensation of extra external force. 125 AN 4326656. AU Kim-W-S. Schenker-P. IN Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA. TI A teleoperation training simulator with visual and kinesthetic force virtual reality. SO Proceedings of the SPIE - The International Society for Optical Engineering. vol.1666. pp. 560-9. 1992. CT Human Vision, Visual Processing and Digital Display III. San Jose, CA, USA. SPIE. Soc. Imaging Sci. Technol. 10-13 Feb. 1992. YR 1992. RN CCCC: 0 8194 0820 4/92/$4.00. AB A force-reflecting teleoperation training simulator with a high-fidelity real-time graphics display has been developed for operator training. A novel feature of this simulator is that it enables the operator to feel contact forces and torques through a force-reflecting controller during the execution of the simulated peg-in-hole task, providing the operator with the feel of visual and kinesthetic force virtual reality. A peg-in-hole task is used in the simulated teleoperation trainer as a generic teleoperation task. A quasi-static analysis of a two-dimensional peg-in-hole task model has been extended to a three-dimensional model analysis to compute contact forces and torques for a virtual realization of kinesthetic force feedback. The simulator allows the user to specify force reflection gains and stiffness (compliance) values of the manipulator hand for both the three translational and the three rotational axes in Cartesian space. Three viewing modes are provided for graphics display: single view, two split views, and stereoscopic view. 126 AN 4323562. AU Driels-M. Spain-H. Aviles-W. IN Dept. of Mech. Eng., Naval Postgraduate Sch., Monterey, CA, USA. TI The effect of sensory feedback on the identification of objects using a teleoperator. SO Automation in Construction. vol.1, no.2. pp. 167-73. Sept. 1992. YR 1992. AB The authors discuss the role that the haptic system plays in teleoperation i.e. the exploration and manipulation of objects by a human operator using a remote robot arm. The approach is to incrementally enhance the remote touch-sensing capability beyond kinesthetic force feedback to include contact data and local re-perception and compare the time to identify quasi-two dimensional objects with that of a directly held probe. Results obtained indicated that action between the remote probe and the environment made the force feedback signal 'noisy' leading to conflicting and inaccurate hypothesis by the operators. Sensory feedback improved the signal to noise ratio giving performance levels approaching those of direct, as opposed to remote probing. 127 AN 4318847. AU Bicchi-A. Melchiorri-C. Edited by: Troch-I. Desoyer-K. Kopacek-P. IN Dept. of Electr. Syst. & Autom., Pisa Univ., Italy. TI Quasi-static compensation of force errors for flexible manipulators. SO Published by: Pergamon. Oxford, UK. 1992. CT Robot Control 1991 (SYROCO '91). Selected Papers from the 3rd IFAC/IFIP/IMACS Symposium. Vienna, Austria. pp. 381-5. IFAC. IFIP. IMACS. 16-18 Sept. 1991. YR 1992. AB This paper deals with the problem of controlling the interactions of flexible manipulators with their environment. For executing a force control task, a manipulator with intrinsic (mechanic) compliance has some advantages over a rigid manipulator. On the other hand, the deformations of the arm under the applied load give rise to errors in the evaluation of the kinematic model of the arm based on its rigid model. Since force feedback is usually provided by a force/torque sensor placed at the end-effector, kinematic errors reflect in force sensing errors, when a force task is specified in the world frame. This paper addresses the problem of evaluating these errors, and of compensating for them with suitable joint angle corrections. A solution to this problem is proposed in the simplifying assumptions that an accurate model of the arm flexibility is known, and that quasi-static corrections are of interest. 128 AN 4318817. AU Gao-W-B. Cheng-M. Xiao-D. Edited by: Troch-I. Desoyer-K. Kopacek-P. IN Seventh Res. Div., Beijing Univ. of Aeronaut., Astronautics, China. TI Force control for tracking a set of tasks in presence of constraints. SO Published by: Pergamon. Oxford, UK. 1992. CT Robot Control 1991 (SYROCO '91). Selected Papers from the 3rd IFAC/IFIP/IMACS Symposium. Vienna, Austria. pp. 201-6. IFAC. IFIP. IMACS. 16-18 Sept. 1991. YR 1992. AB A new approach to tracking tasks by robots in the presence of environmental constraints is proposed. When the equations of the object as a rigid body are written in a component form with respect to axes fixed with the object, a new model of constraints is given in a very simple form as linear functions of velocity components. As a result, the system of differential equations of the motion of the object is automatically decomposed into two subsystems: equations of motion and equations of reactive force. Two schemes of force feedback are given. A hierarchical architecture is established for the overall control strategy such that the robot can track a set of different objects, may be with different desired motion. 129 AN 4312743. AU Sato-M. IN Precision & Intelligence Lab., Tokyo Inst. of Technol., Yokohama, Japan. TI Force display for virtual reality. SO Journal of the Institute of Television Engineers of Japan. vol.46, no.6. pp. 681-4. June 1992. YR 1992. AB In order to realize virtual space and directly handle an object of the virtual world, it is required for the object to be recognized by hand. Accordingly, it is necessary to feed back tactile sensation or force sense in accordance with the movement of operator's hand and fingers. Such force feedback equipment is different from the regular display and is called a force display. The author reviews the roles of tactile sensation or force sense in the virtual control space, and describes some detailed examples of force display, referring to force display by machines, pressure and tensile force. 130 AN 4292368. AU Cadoz-C. IN LIFIA/IMAG/ACROE, Grenoble, France. TI Instrumental communication interface: modular retroactive keyboard. SO Published by: EC2. Nanterre, France. 1992. CT Informatique '92. International Conference Interface to Real and Virtual Worlds. Proceedings and Exhibition Catalog. Montpellier, France. pp. 43. 23-27 March 1992. YR 1992. AB The device described is retroactive in the sense that it presents to the musical instrumentalist a characteristic mechanical resistance (force feedback) which is a function of the nature of the simulated music-making process. Its modularity allows free choice of the number of keys (or degrees of freedom), and some choice of external shape, key movement paths, spatial and geometrical constraints and types of contact. Descriptions of the sectional motor and alternative joystick mountings are given. 131 AN 4292331. AU Burdea-G. Roskos-E. Silver-D. Thibaud-F. Wolpov-R. IN Rutgers Univ., Piscataway, NJ, USA. TI A distributed virtual environment with dextrous force feedback. SO Published by: EC2. Nanterre, France. 1992. CT Informatique '92. International Conference Interface to Real and Virtual Worlds. Proceedings and Exhibition Catalog. Montpellier, France. pp. 255-65. 23-27 March 1992. YR 1992. AB Force feedback is a welcome enhancement to virtual environments, telerobotics, entertainment, or medicine. The paper describes work towards a distributed system built around the Rutgers Portable Force Feedback Master. This maser gives force feedback to multiple fingers of the Dataglove (VPL Research Inc.). The system also uses two Sun 4 workstations and a HP graphics workstation communicating over the Ethernet. Several examples are presented of virtual dextrous force feedback. 132 AN 4292308. TI Informatique '92. International Conference Interface to Real and Virtual Worlds. Proceedings and Exhibition Catalog. SO Published by: EC2. Nanterre, France. 766 pp. 1992. CT Informatique '92. International Conference Interface to Real and Virtual Worlds. Proceedings and Exhibition Catalog. Montpellier, France. 23-27 March 1992. YR 1992. AB The following topics were dealt with: virtual reality interface technologies; three-dimensional vision; behavioural animation; natural language interfaces; teleoperation; electronic pen-pads; human factors and interface prototyping; gesture driven interactions and force feedback; virtual reality applications; graphical interface design and implementation; arts and interfaces; computer aided instruction; computer-supported cooperative work; taste and olfactory systems; multimedia; handicapped aids; vehicle driving; multimodal interaction; vocal communication; and visual designation. 133 AN 4280496. AU Yamashita-T. Godler-I. Takahashi-Y. Wada-K. Katoh-R. IN Dept. of Control Eng., Kyushu Inst. of Technol., Japan. TI Peg-and-hole task by robot with force sensor: Simulation and experiment. SO Published by: IEEE. New York, NY, USA. 1991. CT Proceedings IECON '91. 1991 International Conference on Industrial Electrlnics, Control and Instrumentation (Cat. No.91CH2976-9). Kobe, Japan. pp. 980-5 vol.2. IEEE. Soc. Instrum. & Control Eng. Japan. 28 Oct.-1 Nov. 1991. YR 1991. RN CCCC: CH2976-9/91/0000-0980$01.00. AB A simple peg-and-hole task using a robot with a force-torque sensor mounted in a wrist was studied. The goal of the research was to test if the insertion can be successfully performed by using only a robot with force feedback and no other special tools. There was no chamfer provided either on the hole's edge or on the peg's edge, to preserve geometrical independence of the insertion procedure. Simulations and experiments showed that the insertion is possible if an appropriate insertion procedure with a hybrid position/force controller is used. Conditions for a peg to be jammed in a hole were studied and it was found out that jamming can be avoided when a force control loop reference point is placed at the peg's tip. 134 AN 4225806. AU Preumont-A. Dufour-J-P. Malekian-C. IN Free Univ. of Brussels, Belgium. TI Active damping by a local force feedback with piezoelectric actuators. SO Journal of Guidance, Control, and Dynamics. vol.15, no.2. pp. 390-5. March-April 1992. YR 1992. RN CCCC: 0731-5090/92/$2.00+.50. AB This paper summarizes research in the field of active damping of space structures. The test facility consists of a truss structure provided with two active elements that can be placed in various locations. Each of the active elements consists of a linear piezoelectric actuator collocated with a force transducer. Each active element is controlled in a decentralized manner, with an integral feedback of the force on the voltage applied to the piezoactuator. This control law is always stable and has been found very effective; the damping ratio of the first mode has been increased from 0.003 (open loop) to 0.09 with one actuator. 135 AN 4221231. AU Carre-M. Grignon-P. Lefebvre-J-M. TI A command sequence for the control of maintenance robots in nuclear power plants. SO La Technique Moderne. vol.84, no.1-3. pp. 39-42. March 1991. YR 1991. AB The authors attempt to provide a generic solution to problems to provide solution to problems of robot command in the steam generator by endowing robots with possibilities of adapting to their environments as well as of communicating with the processes. The concept calls for software and hardware which is either standard or in the process of being standardized by the company. for the user interface ACT CAD-robotics software permits piloting of redundant robots, with obstacle avoidance by means of the local-based approach for path-planning manipulators. This software provides multiwindow 3D display. The environment is managed by a relational database: physical objects and their relationships are clearly identified graphically by users who can manipulate and modify them with ease. A number of icons permit manual or automated piloting of robots, as well as access to all parameters for configuration and operation of the robotic cell. An Ethernet network allows communication with the real-time controller of the robot, using a standard transmission protocol based on TCP/IP. The first industrial application is the Flexivera robot for which the industrial prototype was completed at the end of 1991. An attempt will be made to repeat this architecture in other contexts, most particularly in 1992 that of remote manipulation with force feed-back. The long-term objective is to achieve an open structure with proven reliability for all telerobotic applications. 136 AN 4218652. AU Macfarlane-K-T. Matthew-D. Macdonald-S. Evans-R. IN Dept. of Comput. Sci., Paisley Coll., UK. TI Development of PC and transputer-based walking robots. SO Published by: IEE. London, UK. 1992. CT IEE Colloquium on 'Multi-Arm Robotics' (Digest No.147). London, UK. pp. 6/1-10. IEE. 17 June 1992. YR 1992. AB Robotic walking is one of the key activities on the critical path to the integration of computers into a world designed for use by bipeds, the others being real-time image processing, scene analysis and depth ranging, and touch sensors for force feedback. The dynamic control of balance while walking, by stepwise refinement of controllers for successively decreasing numbers of legs is considered. With this aim the authors have constructed a 6, a 4, and most recently a 2 legged robot. The work done on PC and transputer-based hexapod and quadruped is described. 137 AN 4206226. AU Tomono-A. Kishino-F. TI Human interface technology for communication with realistic sensations. SO Journal of Japanese Society for Artificial Intelligence. vol.6, no.3. pp. 358-69. May 1991. YR 1991. AB The following topics are discussed: human interfaces; virtual space; realism; telecommunication; teleconferencing; eye movement detection; stereoscopic display; direct manipulation; and force feedback. 138 AN 4206207. AU Fukui-Y. Shimojo-M. IN Ind. Products Res. Inst., Tsukuba, Japan. TI Edge tracing of virtual shape using input device with force feedback. SO Systems and Computers in Japan. vol.23, no.5. pp. 94-104. 1992. YR 1992. RN CCCC: 0882-1666/92/0005-0094$7.50/0. AB In manipulating shapes displayed on a screen by means of a keyboard, mouse, or tablet, the operator can only confirm his/her operation visually through the eyes. This process can easily cause eye fatigue, resulting in low work efficiency. To improve this situation, a reaction force to the operator's hands should also be used to provide feedback from the operation. The authors have devised an input device based on this idea. Its main feature is a two-dimensional force sensor mounted on the head of an XY recorder connected to a graphics computer. The XY recorder head with mounted sensor can be controlled by the computer to move in the direction in which the finger force is applied. Using this input device, the authors have done experiments on human sensitivity to virtual shapes through following their contours when force feedback is available. 139 AN 4203788. AU Kotoku-T. Tanie-K. Fujikawa-A. IN Mech. Eng. Lab., AIST-MITI., Ibaraki, Japan. TI Environment modeling for the interactive display (EMID) used in telerobotic systems. SO Published by: IEEE. New York, NY, USA. 1991. CT Proceedings IROS '91. IEEE/RSJ International Workshop on Intelligent Robots and Systems '91. Intelligence for Mechanical Systems (Cat. No.91TH0375-6). Osaka, Japan. pp. 999-1004 vol.2. IEEE. RSJ. SICE. New Technol. Found. JSME. et al. 3-5 Nov. 1991. YR 1991. AB Discusses a method of calculating the interaction forces produced between objects which will contact in model space. Recently, needs of robotic simulators are increasing to provide efficient off-line teaching tools, effective human-robot interfaces for telerobotic systems and so on. In almost simulators, currently operators can see good images of the environments to be manipulated by introducing computer graphics techniques. However, such simulators only can display the environments unilaterally without feeling any constraint force which will occur during teaching tasks. In some applications of the simulators, the lack of force feedback causes low efficiency of the system. In order to overcome this problem, a method which can generate constraint forces in a model world is proposed, which will be called the EMID (environment modeling for the interactive display) system. After the method is formulated, using the EMID method will be confirmed. 140 AN 4199174. AU Inoue-Y. Kitamura-S. Kidawara-Y. IN Graduate Sch. of Sci. & Technol., Kobe Univ., Japan. TI Force feedback control and collision avoidance of redundant manipulator. SO Published by: IEEE. New York, NY, USA. 1991. CT Proceedings IROS '91. IEEE/RSJ International Workshop on Intelligent Robots and Systems '91. Intelligence for Mechanical Systems (Cat. No.91TH0375-6). Osaka, Japan. pp. 149-52 vol.1. IEEE. RSJ. SICE. New Technol. Found. JSME. et al. 3-5 Nov. 1991. YR 1991. AB A method of compliant and collision avoidance control is presented. The collision avoidance motion is first generated in off-line routine and its data are stored as as a sequence of desired joint angles. Next, virtual impedance model-following control is employed as force feedback control. Redundancy is used for minimization of the variance from the desired joint angle during compliant motion. In particular, the computation time for the inverse kinematics at each sampling time was reduced by using approximate values of Jacobian matrix. The stability of the control system is analyzed and the effectiveness of the proposed method is discussed. 141 AN 4193974. AU Funda-J. Paul-R-P. Edited by: Zajc-B. Solina-F. IN Pennsylvania Univ., Philadelphia, PA, USA. TI Model-based, delay-tolerant teleoperation in unstructured environments. SO Published by: IEEE. New York, NY, USA. 1991. CT 6th Mediterranean Electrotechnical Conference. Proceedings. (Cat. No.91CH2964-5). LJubljana, Slovenia. pp. 908-11 vol.2. IEEE. 22-24 May 1991. YR 1991. RN CCCC: CH2964-5/91/0000-0908$01.00. AB The problem of teleoperation in the presence of communication delays is addressed. Because of the delay in obtaining position and force feedback from the remote slave arms, direct teleoperation is not feasible. A combination of computer graphics and manipulator programming is proposed to solve the problem by allowing the operator to kinesthetically, as well as visually, interact with a graphical simulation of the remote environment and to interactively (online) teleprogram the remote manipulator through a sequence of elementary symbolic instructions, which are generated automatically by the operator's station software. The slave robot executes these symbolic commands delayed in time and, should an error occur, reports the relevant information back to the operator's station, where the master environment is reset to the error state. 142 AN 4181818. AU Kim-W-S. Hannaford-B. Fejczy-A-K. IN Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA. TI Force-reflection and shared compliant control in operating telemanipulators with time delay. SO IEEE Transactions on Robotics and Automation. vol.8, no.2. pp. 176-85. April 1992. YR 1992. RN CCCC: 1042-296X/92/$03.00. AB Shared compliant control has been incorporated into an advanced six-degree-of-freedom force-reflecting telemanipulation system. With this system the authors have investigated the effect of time delay on human telemanipulation task performance. Time delays of between 2 and 4096 ms were introduced between master and slave arms, and high-precision peg-in-hole tasks were performed by six test operators with two modes of control: kinesthetic force feedback (KFF) and shared compliant control (SCC). Task performance was quantified in terms of the completion time (CT) and the sum of square forces (SOSF). The experimental results demonstrate the superiority of SCC over KFF for time-delayed telemanipulation. SCC has significantly lower rates of increase than KFF in both CT and SOSF with time delay. Only SCC enabled task performance at delays above 1 s. Constant force maintenance tasks were also performed to investigate the effect of time delay on the stability of force reflection. SCC also has beneficial effects on telemanipulation without time delay. 143 AN 4174007. AU Luciani-A. Jimenez-S. Florens-J-L. Cadoz-C. Raoult-O. Edited by: Post-F-H. Barth-W. IN Inst. d'Inf. et de Math. Appliquees de Grenoble, France. TI Computational physics: a modeler-simulator for animated physical objects. SO Published by: North-Holland. Amsterdam, Netherlands. 1991. CT EUROGRAPHICS '91. Proceedings of the European Computer Graphics Conference and Exhibition. Vienna, Austria. pp. 425-37. 2-6 Sept. 1991. YR 1991. AB Physical modeling for animation is now firmly established. The authors design and build a structured and well-defined tool rather than merely specific algorithms to simulate physical knowledge. The authors first define the basic functions of a modeler-simulator for physical modeling which enables operator gestural control, and where the simulation processes are real time oriented. These constraints cannot be achieved by any kind of models and algorithms. Concerning the theoretical elements, the choice of the underlying physics and the categorization of interactions are presented. They then introduce the Cordis-Anima system, its constructive language, its real time simulator and its force feedback gestural transducers. Finally, they describe, with some examples, how they model, simulate and manipulate a large variety of physical objects and scenes. 144 AN 4173778. AU Murphy-S-H. Wen-J-T. IN Rensselaer Polytech. Inst., Troy, NY, USA. TI Force decomposition in robot force control. SO Published by: American Autom. Control Council. Evanston, IL, USA. 1991. CT Proceedings of the 1991 American Control Conference (IEEE Cat. No. 91CH2939-7). Boston, MA, USA. pp. 2533-8 vol.3. American Autom. Control Council. 26-28 June 1991. YR 1991. AB The unit inconsistency in force decomposition has motivated an investigation into the force control problem in multiple-arm manipulation. Based on physical considerations, it is argued that the force that should be controlled is the internal force at the specified frame in the payload. This force contains contributions due to both applied forces from the arms and the inertial force from the payload and the arms. A least-squares scheme free of unit inconsistency for finding this internal force is presented. The force control issue is analyzed, and an integral force feedback controller is proposed. 145 AN 4168953. AU Singh-S-K. Waite-D-T. IN Thayer Sch. of Eng., Dartmouth Coll., Hanover, NH, USA. TI Precise tip-position control of a cable-controlled flexible beam. SO Published by: American Autom. Control Council. Evanston, IL, USA. 1991. CT Proceedings of the 1991 American Control Conference (IEEE Cat. No. 91CH2939-7). Boston, MA, USA. pp. 1440-1 vol.2. American Autom. Control Council. 26-28 June 1991. YR 1991. AB A unique concept is proposed: a single flexible link, which can be deformed into desired configurations. A single link may thus provide multiple degrees of freedom. Further, the authors suggest the use of cable tensions as the prime movers of this link, and the use of force feedback, to control the cable tensions. 146 AN 4154871. AU Brogliato-B. Lozano-Leal-R. IN Lab. d'Autom. de Grenoble, CNRS, ENSIEG-INPG, Saint-Martin d'Heres, France. TI Adaptive force/position control of constrained manipulators with flexible joints. SO Published by: American Autom. Control Council. Evanston, IL, USA. 1991. CT Proceedings of the 1991 American Control Conference (IEEE Cat. No. 91CH2939-7). Boston, MA, USA. pp. 968-9 vol.1. American Autom. Control Council. 26-28 June 1991. YR 1991. AB A hybrid controller for flexible joint manipulators subject to holonomic constraints is presented. The basic methods have been extended making use of physical properties of manipulators. The position and force tracking errors are shown to converge asymptotically to zero when all the physical parameters are known. In the adaptive case, only the position error converges to zero while the force error remains bounded. However, stability is insured for any value of the joint flexibility K. Measurements of the joints and motorshaft position and velocity only are needed, though the schemes can be improved by adding a force feedback term in the control law. 147 AN 4147631. AU Mat-Isa-A-R. Usher-M-J. IN Dept. of Cybern., Reading Univ., UK. TI An angular accelerometer for reducing the effects of tilt in seismic records. SO Geophysical Journal International. vol.109, no.1. pp. 197-208. April 1992. YR 1992. AB Seismometers for measuring horizontal vibrations respond not only to the required ground motion but also to unwanted tilts, cause by atmospheric or local effects. Because of th equivalence of inertial and gravitational accelerations, it is not possible to separate these effects in a single instrument. However, absolute rotation is detectable and an angular accelerometer has been developed, responding only to tilt and not to either horizontal or vertical ground motion. The design of the instrument is very similar to that of a modern horizontal-component seismometer, comprising a double balanced pendulum pivoted at its centre of gravity and operated in a force feedback configuration. Details of the design, testing and calibration are presented. Recordings obtained under different conditions of wind and seismic activity are presented. 148 AN 4144927. AU Suehiro-T. Edited by: Devanathan-R. IN Fukuoka Ind. Technol. Center, Mechanics & Electron. Res. Inst., Kitakyusyu, Japan. TI Adaptive control for a robot arm and a robot drive system with elasticity. SO Published by: Pergamon Press. Oxford, UK. 1991. CT Intelligent Tuning and Adaptive Control. Selected Papers from the IFAC Symposium. Singapore. pp. 199-204. IFAC. Instrum. Control Soc. IEEE. 15-17 Jan. 1991. YR 1991. AB First, this paper presents an application of a model reference adaptive control system (MRACS) to the position control, and the force feedback control of a flexible robot arm. Second, this paper investigates the application of an MRACS to the speed control, and the position control of a DC servo system and a direct-drive(DD) servo system with a flexible transmission element. The flexible robot arm is simply modelled as a flexible cantilever beam. The servo systems with a flexible transmission element are treated as a servo mechanism with a one degree of freedom oscillatory load. Using discrete-time mathematical models as a lumped parameter system, the discrete MRACS is designed for each discrete model. Experimental results have shown that the control performance is good and the MRACS is effective. 149 AN 4143821. AU Matsueda-T. Kuraoka-K. Goma-K. Sumi-T. Okamura-R. IN Nat. Space Dev. Agency of Japan, Tokyo, Japan. TI JEMRMS system design and development status. SO Published by: IEEE. New York, NY, USA. 1991. CT NTC '91. National Telesystems Conference Proceedings. Vol.1. (Cat. No.91CH3010-6). Atlanta, GA, USA. pp. 391-5. IEEE. 26-27 March 1991. YR 1991. RN CCCC: CH3010-6/91/0391$01.00. AB The authors present an overview of the baseline configuration of the JEMRMS (Japanese Experiment Module Remote Manipulator System) and summarize the status of the system and element development tests. JEMRMS has mother-daughter type manipulators: a 10 m long mother arm (main arm) and a 2 m-long daughter arm (small fine arm). The main arm (MA) provides that capability of transferring, retrieving, and berthing user (mission) payload or a JEM element in the vicinity of the servicing bay, called the exposed facility. The small fine arm (SFA), which is attached to the MA, performs dexterous tasks such as assembly of antenna and change-out test samples. The MA is routinely controlled by an automatic control mode, but can also be controlled by a manual mode using a six degree-of-freedom hand controller. The SFA is controlled by a manual control mode mainly in a bilateral (force feedback) and master-slave fashion. The MA is commonly used for the SFA as will as the MA and provides a human operator with the feedback force detected by a force moment sensor at the SFA wrist. 150 AN 4127255. AU Joyce-S-A. Houston-J-E. Smith-B-K. IN Sandia Nat. Lab., Albuquerque, NM, USA. TI Interfacial force sensor with force-feedback control. SO Published by: IEEE. New York, NY, USA. 1990. CT International Electron Devices Meeting 1990. Technical Digest (Cat. No.90CH2865-4). San Francisco, CA, USA. pp. 621-4. IEEE. 9-12 Dec. 1990. YR 1990. RN CCCC: CH2865-4/90/0000-0621$01.00. AB A novel interfacial force microscope capable of measuring the forces between two surfaces over the entire range of surface separations, up to contact, has been developed. The design is centered around a differential capacitance displacement sensor where the common capacitor plate is supported by torsion bars. A force-feedback control system balances the interfacial forces at the sensor, maintaining the common capacitor plate at its rest position. This control eliminates the instability which occurs with the conventional cantilever-based force sensors when the attractive force gradient exceeds the mechanical stiffness of the cantilever. The ability to measure interfacial forces at surface separations smaller than this instability point using the feedback control is demonstrated. 151 AN 4125071. AU Fiala-J. Wavering-A-J. IN Robot Syst. Div., Nat. Inst. of Stand. & Technol., Gaithersburg, MD, USA. TI Experimental evaluation of Cartesian stiffness control on a seven degree-of-freedom robot arm. SO Journal of Intelligent and Robotic Systems: Theory and Applications. vol.5, no.1. pp. 5-24. Feb. 1992. YR 1992. AB The programmability of Cartesian stiffness in Cartesian servo control algorithms that do not use explicit force feedback is examined. A number of Cartesian algorithms are implemented and evaluated on a commercial seven degree-of-freedom robot arm, using the NASREM robot control system testbed. It is found that Cartesian servo algorithms which use the transpose of the Jacobian and model-based gravity compensation, provide easy programmability and accurate reproduction of stiffnesses over a wide range. When dynamic behavior is a consideration, dynamic damping control, augmented to include a parameterization of the manipulator self-motion, provides superior performance and programmability. 152 AN 4121339. AU Burdea-G. Jiachen-Zhuang. Roskos-E. Silver-D. Langrana-N. Edited by: Tzafestas-S-G. IN Coll. of Eng., Rutgers State Univ. of New Jersey, Piscataway, NJ, USA. TI Direct-drive force feedback control for the Dataglove. SO Published by: Kluwer Academic Publishers. Dordrecht, Netherlands. 1991. CT Engineering Systems with Intelligence. Concepts, Tools and Applications. Corfu, Greece. pp. 453-60. 23-28 June 1991. YR 1991. AB Dextrous masters control robots or artificial environments through hand gestures. The paper describes a portable dextrous master with force feedback that uses several pneumatic actuators placed in the hand. The resulting system is light, compact, desk-top and relatively inexpensive. This system addresses the needs of certain applications which now operate in open-loop and where the addition of feedback to some degrees of freedom is beneficial. The authors describe the system hardware configuration. They then give actuator characteristics and a model for the control loop. 153 AN 4106548. AU Kim-W-S. Backes-P-G. Hayati-S. Bokor-E. IN Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA. TI Orbital replacement unit changeout experiments with a telerobot testbed system. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1991. CT Proceedings. 1991 IEEE International Conference on Robotics and Automation (Cat. No.91CH2969-4). Sacramento, CA, USA. pp. 2026-31 vol.3. IEEE. 9-11 April 1991. YR 1991. RN CCCC: CH2969-4/91/0000-2026$01.00. AB Orbital replacement unit (ORU) changeout experiments were performed with the JPL/NASA telerobot testbed system for three different control modes: force reflecting teleoperation (FR), shared compliant control (SCC), and autonomous control (AC). In FR, the operator was provided with kinesthetic force feedback, feeling contact forces through a force-reflecting hand controller. In SCC, the operator controlled a compliant robot, where the robot compliance was implemented by an autonomous compliant control force feedback. In AC, telemanipulation tasks were performed autonomously by using a sequence of macros. Experimental results indicate that SCC greatly reduces the magnitudes and durations of contact forces as compared to FR. AC took the least time to complete the ORU changeout task and, with appropriate operator intervention capabilities, it could be very pleasant to use in some applications with well-structured task environments. 154 AN 4102061. AU Nguyen-T. Wang-J. Hwang-J. Alder-K. IN Lockheed Eng. & Sci. Co., Houston, TX, USA. TI Force accommodation control of the Space Shuttle remote manipulator system: a unique problem. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1991. CT Proceedings. 1991 IEEE International Conference on Robotics and Automation (Cat. No.91CH2969-4). Sacramento, CA, USA. pp. 2510-15 vol.3. IEEE. 9-11 April 1991. YR 1991. RN CCCC: CH2969-4/91/0000-2510$01.00. AB The Space Shuttle remote manipulator system (SRMS) is a man-in-the-loop, rate-servoed manipulator that has flown on numerous shuttle missions. A force feedback control law is being investigated for the SRMS to enhance its capabilities for current shuttle robotic activities and future space station tasks. Since it is not feasible to experiment with the SRMS in a laboratory environment, control laws are developed and tested on an industrial manipulator while the different SRMS dynamic characteristics relative to the experimental arm are identified using simulation models. These unique characteristics complicate the design of a force control law for the SRMS. The approach used and preliminary results are discussed. 155 AN 4100201. TI A remotely operated excavator(nuclear applications). SO Nuclear Engineering International. vol.37, no.450. pp. 41-3. Jan. 1992. YR 1992. AB Force feedback enables a single operator to use the HAZ-TRAK remotely operated excavator with ease at nuclear waste sites and during decommissioning of nuclear facilities. 156 AN 4097126. AU Fukuda-T. Fujiyoshi-M. Arai-F. Matsuura-H. IN Dept. of Mech. Eng., Nagoya Univ., Japan. TI Design and dextrous control of micromanipulator with 6 DOF. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1991. CT Proceedings. 1991 IEEE International Conference on Robotics and Automation (Cat. No.91CH2969-4). Sacramento, CA, USA. pp. 1628-33 vol.2. IEEE. 9-11 April 1991. YR 1991. RN CCCC: CH2969-4/91/0000-1628$01.00. AB A six-degree-of-freedom micromanipulator using PZT actuators has been designed and tested. The micromanipulator is very small and light, because it is made of PZT actuators. Since this micromanipulator has a position and force feedback system, it can control desired poses and forces. Since the manipulator has 6 degrees of freedom, its tip can move along three axes, and can also rotate along each axis. A fuzzy-like variable gain feedback control system is employed, making this system perform better than the fixed gain feedback system. These technical merits will make it possible to operate this dextrous micromanipulator in much more complicated environments under a microscope. 157 AN 4084955. AU Ahmad-S. Lee-C-N. IN Real-Time Robot Control Lab., Sch. of Electr. Eng., Purdue Univ., West Lafayette, IN, USA. TI Shape recovery from robot contour-tracking with force feedback. SO Advanced Robotics. vol.5, no.3. pp. 257-73. 1991. YR 1991. AB The authors describe a process for shape recovery from robot contour-tracking operations with force feedback. Shape recovery is an important task for self-teaching robots and for exploratory operations in unknown environments. An algorithm which directs a position-controlled robot around an unknown planar contour using the steady-state contact force information is described. Shape recovery from planar contouring is not a trivial problem. It was found experimentally that there is significant distortion of the original contour is direct kinematics are used to recover the object's shape, as it is not possible to recover the exact position of the robot tool owing to the errors present in the kinematic model of the arm and the nonlinearities of the drive train. Drive train errors can consist of the joint compliance, gear backlash, and gear eccentricity. A mathematical model of the errors generated by the drive train has been previously addressed. A compensation process is explored for purposes of planar shape recovery. It was found through experimentation that the joint compliance is most conveniently compensated for in practice. Improvements in the shapes recovered from robot contouring result from the compensations. Experimental details and difficulties are also discussed. 158 AN 4066535. AU Brossard-J-P. IN La Calhene, Villacoublay, France. TI Ten years of life for the MA23M servomanipulator. SO Transactions of the American Nuclear Society. vol.64. pp. 602. 1991. CT American Nuclear Society 1991 Winter Meeting (papers in summary form only received). San Francisco, CA, USA. 10-14 Nov. 1991. YR 1991. AB The MA23M is a force-feedback servomanipulator with a handling capacity of 23 daN. The actuators are direct current torquers equipped with potentiometers, and tapes and cables provide the transmissions. The servocontrol is analog, and the link between master and slave is analog through a multicore electrical cable. Specially designed to be repaired in a glove box, the slave arm is protected by a ventilated booting working under pressure, allowing its use in highly alpha contaminated atmosphere; its irradiation resistance is limited to 5.10 to 7 rad. Equipped with a special device, the MA23M can be used under 20 m of water without modification. Fifteen identical manipulators have been delivered since 1982. The MA23M can be classed as industrial equipment: all components are interchangeable piece by piece, and the simple design and validated manuals allow a suitably qualified technician to do the maintenance. 159 AN 4056555. AU Jae-Ook-Jeong. Bum-Hee-Lee. Myoung-Sam-Ko. TI A study on the implementation of edge-following insertion and grinding tasks using robot force control. SO Transactions of the Korean Institute of Electrical Engineers. vol.40, no.2. pp. 207-16. Feb. 1991. YR 1991. AB The robot force control method is implemented with a force/torque sensor, two personal computers, and a PUMA 560 manipulator for performing the various application tasks. The hybrid position/force control method is used to control the force and position axis separately. An interface board is designed to read the force/torque sensor output into the computer. Since the two computers should exchange the information quickly, a common memory board is designed. Before the algorithms of application tasks are developed, the basic force commands must be supplied. Thus, the MOVE-UNTIL command is used at the discrete time instant and the MOVE-COMPLY is used at the continuous time instant for receiving the force feedback information. Using the two basic force commands, three application algorithms are developed and implemented for edge-following, insertion, and grinding tasks. 160 AN 4056326. AU Nguyen-C-C. Antrazi-S-C. Zhen-Lei-Zhou. Campbell-C-E-Jr. IN Dept. of Electr. Eng., Catholic Univ. of America, Washington, DC, USA. TI Analysis and implementation of a 6 DOF Stewart platform-based robotic wrist. SO Computers & Electrical Engineering. vol.17, no.3. pp. 191-203. 1991. YR 1991. RN CCCC: 0045-7906/91/$3.00+0.00. AB Presents the kinematic analysis and implementation of a 6 DOF robotic wrist which is mounted to a general open-kinematic chain manipulator to serve as a testbed for studying precision robotic assembly in space. The wrist design is based on the Stewart platform mechanism and consists mainly of two platforms and six linear actuators driven by DC motors. Position feedback is achieved by linear displacement transducers mounted along the actuators and force feedback is obtained by a 6 DOF force sensor mounted between the gripper and the payload platform. The robot wrist inverse kinematics, which computes the required actuator lengths corresponding to Cartesian variables, has a closed-form solution. The forward kinematics is solved iteratively using the Newton-Raphson method which simultaneously provides a modified Jacobian matrix which relates length velocities to Cartesian translational velocities and time rates of change of roll-pitch-yaw angles. Results of computer simulation conducted to evaluate the efficiency of the forward kinematics and modified Jacobian matrix are presented and discussed. 161 AN 4052613. AU Sato-M. TI Interface device for artificial reality. SO Journal of the Japan Society of Precision Engineering. vol.57, no.8. pp. 1343-6. Aug. 1991. YR 1991. AB The author discusses artificial reality, virtual space, force feedback, perception cycle, the interface device, and CAD. 162 AN 4052609. AU Iwata-H. TI Virtual reality and force display. SO Journal of the Japan Society of Precision Engineering. vol.57, no.8. pp. 1326-9. Aug. 1991. YR 1991. AB The author discusses virtual reality, artificial reality, force feedback, tactile sensors, haptics and interactive graphics. 163 AN 4052066. AU Hannaford-B. Wood-L. McAffee-D-A. Zak-H. IN Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA. TI Performance evaluation of a six-axis generalized force-reflecting teleoperator. SO IEEE Transactions on Systems, Man and Cybernetics. vol.21, no.3. pp. 620-33. May-June 1991. YR 1991. RN CCCC: 0018-9472/91/0500-0620$01.00. AB Recent work in real-time distributed computation and control has culminated in a prototype force-reflecting telemanipulation system having dissimilar master (cable-driven force-reflecting hand controller) and slave (PUMA 560 robot with custom controller), extremely high sampling rate (1000 Hz), and low loop computation delay (5 ms). In a series of experiments with this system and five trained test operators covering more than 100 h of teleoperation, performance in a series of generic and application-driven tasks with and without force feedback was measured, and with control shared between teleoperation and local sensor referenced control. Measurements defining task performance include 100-Hz recording of six-axis force-torque information, task completion time, and visual observation of predefined task errors. It is shown that all performance measures improved as capability was added along a spectrum of capabilities ranging from pure position control through force-reflecting teleoperation and shared control. Performance was maximal for the barehanded operator. 164 AN 4043225. AU Fukui-Y. Shimojo-M. IN Ind. Products Res. Inst., Tsukuba, Japan. TI Edge tracing of virtual shape using input device with force feedback. SO Transactions of the Institute of Electronics, Information and Communication Engineers D-II. vol.74D-II, no.8. pp. 1052-9. Aug. 1991. YR 1991. AB The input devices that are commonly used for computers are the keyboard mouse and tablet. However it is inconvenient and tiring for the operator to handle shapes defined in the computer with such devices, because the feedback of operation by his hands are only obtained by the visual organs. Force feedback is required in such a case. Therefore, have developed input devices with force feedback, by 2-dimensional force sensor attached to the head of XY-recorder. The authors have taken experiment of tracing the edges of virtual shapes and recognized the slight change of curvature more easily with the developed device than without it. Through this experiment, they have found that force feedback is desirable for the interactive device. 165 AN 4029847. AU Luo-Zhi-wei. Kato-A. Ito-M. IN Fac. of Eng., Nagoya Univ., Japan. TI On adaptation of robot to dynamic environment in compliant manipulation. SO Transactions of the Society of Instrument and Control Engineers. vol.27, no.7. pp. 806-14. July 1991. YR 1991. AB Concerns the control of a robot to perform compliant manipulation on unknown dynamic environments. Compliant manipulation requires the robot to adapt to environment dynamics. For manipulators to succeed in performing such manipulation, control of position or force alone is inadequate. Focussing on the input-output responses of position and force of the robot control system, the authors propose a model-matching approach. For the selection of a reference model and the design of a force feedback compensator, accurate information on environment dynamics is needed. However, in most contact tasks, the dynamics are known poorly if at all. Based on very unfavourable cases, the authors give an algorithm for robot manipulators to adapt to the unknown environment dynamics autonomously during the manipulation. An experimental system of 1 d.o.f. robot and its environment is used to study various control approaches. 166 AN 4012792. AU Benady-M. Flash-T. Gershon-D. Edited by: Halevi-G. Weill-R. Yudilevich-I. IN Dept. of Appl. Math. & Comput. Sci., Weizmann Inst. of Sci., Rehovot, Israel. TI Robot learning of contact tasks. SO Published by: North-Holland. Amsterdam, Netherlands. 1990. CT Robotic Systems and AMT. Proceedings of the IFIP TC5/WG 5.3 International Conference. Jerusalem, Israel. pp. 147-59. 11-14 Dec. 1989. YR 1990. AB Describes a learning scheme for an impedance-controlled robot performing manipulation tasks. An impedance controller was developed in which an outer impedance control loop is closed around an inner position control loop. This approach requires force feedback from a wrist force sensor mounted between the robot flange and the tool. Optimal impedance parameters are learned using an associative search network (ASN). The network solves an optimization problem of minimizing the deviation of the manipulator tip from specified criteria (e.g. force and velocity profiles). The learning scheme is a stochastic scheme which uses a single scalar value as a measure of the system performance. The learning scheme was implemented for a surface-following task on the Adept-One manipulator. 167 AN 4002587. AU Patrick-N-J-M. Sheridan-T-B. Massimino-M-J. Marcus-B-A. IN Dept. of Mech. Eng., MIT, Cambridge, MA, USA. TI Design and testing of a nonreactive, fingertip, tactile display for interaction with remote environments. SO Proceedings of the SPIE - The International Society for Optical Engineering. vol.1387. pp. 215-22. 1991. CT Cooperative Intelligent Robotics in Space. Boston, MA, USA. SPIE. 6-7 Nov. 1990. YR 1991. RN CCCC: 0277-786X/91/$4.00. AB During interaction with remote environments, the operator may benefit from the addition of force feedback to the ubiquitous visual feedback. However, the apparatus required for reactive force feedback (feedback which imposes the remote environment's motion-constraints on the user by applying joint torques) is cumbersome and expensive, especially when implemented in conjunction with high degree-of-freedom precision joint motion sensing. Nonreactive, tactile feedback can provide similar information, and can be implemented at much lower cost. The purposes of this research were to design and demonstrate an inexpensive tactile feedback system, and to determine the extent to which such a system could aid in the performance of a simple teleoperation task. After experimentation with display technologies, and preliminary design, a vibrotactile display was chosen because of its low weight, size, and low cost. The final design consisted of two voice-coils, one each for the thumb and the index finger, which were driven by a 250 Hz variable-amplitude signal produced by an analog electronics unit controlled by a PC. Experimental results are provided to show that the addition of the tactile display provides a small but significant improvement in manual tracking performance over the use of the visual display alone, and that the tracking task may be performed with only the tactile display. In further experiments the tactile display is compared with reactive force-feedback and is shown to confer most of the reactive display's performance improvement over tracking with only a visual display. 168 AN 3986685. AU Chin-K-P. Sheridan-T-B. Edited by: Smith-M-J. Salvendy-G. IN Dept. of Mech. Eng., MIT, Cambridge, MA, USA. TI The effect of force feedback on teleoperation. SO Published by: Elsevier. Amsterdam, Netherlands. 1989. CT Work With Computers: Organizational, Management, Stress and Health Aspects. Proceedings of the Third Conference on Human-Computer Interaction. Vol.1. Boston, MA, USA. pp. 504-11. Assoc. American Publishers. AT&T. IBM. Perdue Univ. et al. 18-22 Sept. 1989. YR 1989. AB The authors argue that 'telepresence', the sense of being present at a remote location, should be a means to achieve higher performance, but not a purpose in itself. Force feedback, considered as a subset of telepresence, is essential in constrained motion tasks. However, force feedback to the operator may reduce the performance because, firstly, it is fatiguing; secondly, it limits the dexterity and capacity of the system; and thirdly, it causes the teleoperator system to be unstable and hard to control especially in the presence of time delay. Therefore, they suggest that force information should be analyzed and interpreted at the remote site to avoid dynamic coupling between the task and operator. They also discuss the possibility and technology needed to replace force feedback with a supervisory control system in order to achieve a higher performance level in teleoperation. 169 AN 3983654. AU Tedford-J-D. IN Dept. of Mech. Eng., Auckland Univ., New Zealand. TI Design of a robot gripper with force feedback control. SO Mechatronics. vol.1, no.3. pp. 311-19. 1991. YR 1991. RN CCCC: 0957-4158/91/$3.00+0.00. AB The design of a two-jaw robot gripper using a DC servomotor with optical encoder is described. Force control of the gripper is achieved using armature current sensing as a means of detecting motor torque and hence the force applied between the gripper jaws. The motor was modelled mathematically to obtain the second order equation relating the armature current to the applied motor voltage. This relationship was used to develop a proportional-plus-integral digital control algorithm enabling force feedback to be achieved. Two-way communication between the ASEA robot controller and the IBM-XT gripper controller enables a range of gripping forces to be accessed throughout the robot programme cycle, any one of which may be selected at a particular time. Anticipated problems associated with the thermal drift and transient responses have largely been overcome by repeatedly recalibrating the gripper throughout a work shift. 170 AN 3979743. AU Burdea-G. Zhuang-J. IN Dept. of Electr. & Comput. Eng., Rutgers State Univ. of New Jersey, Piscataway, NJ, USA. TI Dextrous telerobotics with force feedback-an overview. 2. Control and implementation. SO Robotica. vol.9, pt.3. pp. 291-8. July-Sept. 1991. YR 1991. AB For pt.I see ibid., vol.9, pt.2, p.171 (1991). The control strategy for a dextrous masters is different from the general case of bilateral teleoperation since it models the human hand in much more detail. Such a model is discussed together with the selection of actuators used for force feedback control. Existing prototypes of dextrous masters with force feedback are then reviewed. These are the Servo-Controlled Manipulator Device, the Portable Dextrous Force Feedback Master (PDMFF), the Remote Handler, and the Advanced Multiple DOF Force Reflective Hand/Wrist Master. 171 AN 3941277. AU Goldenberg-A-A. Bastas-D. Strassberg-Y. IN Dept. of Mech. Eng., Toronto Univ., Ont., Canada. TI On the bilateral control of master-slave teleoperators. SO Robotersysteme. vol.7, no.2. pp. 91-9. May 1991. YR 1991. AB A two-port model of a master-slave system, commonly used in teleoperation, is developed to find the most suitable force feedback controller configuration and parameters. In the paper, results of mathematical analysis and experiments performed on a single axis force reflecting master-slave system are reported. The proposed controller is evaluated experimentally and compared to other controllers. Furthermore, a control scheme for multi-degree of freedom force-reflecting teleoperation systems is proposed. In this scheme, full control over the impedance characteristics of the master arm is obtained. Preliminary simulation results (for a simple decoupled teleoperator) are presented to demonstrate the dynamic behaviour of the proposed control method. 172 AN 3919441. AU Burdea-G. Zhuang-J. IN Dept. of Electr. & Comput. Eng., Rutgers State Univ. of New Jersey, Piscataway, NJ, USA. TI Dextrous telerobotics with force feedback-an overview. 1. Human factors. SO Robotica. vol.9, pt.2. pp. 171-8. April-June 1991. YR 1991. AB Complex tasks that need to be performed through teleoperation led to the development of multifinger robot hands. A dextrous master is a multi-DOF controller which is worn by the operator in order to teleoperate these anthropomorphic hands. Force feedback is very useful when there is interaction with the environment. Providing force feedback to dextrous masters is an area of active research. The authors outline some of the human factors that influence the design of such masters. Of obvious importance is the hand geometry and the desired number of degrees of freedom. Additional criteria relate to the force perception of the hand. Finally, the man-machine impedance is of importance, since at the man/machine interface there are two impedances acting in series. One is the effective impedance of the human operator holding the master controller, the second is the impedance of the master controller being manipulated. 173 AN 3914335. AU Di-Mauro-E-C. Karatzas-L-S. Usher-M-J. IN Dept. of Cybern., Reading Univ., UK. TI Optical tiltmeter. SO Measurement Science & Technology. vol.2, no.4. pp. 346-51. April 1991. YR 1991. RN CCCC: 0957-0233/91/040346+06$03.50. AB An optical tiltmeter has been developed. It comprises a force-feedback pendulum device in which both the sensing and feedback are by means of optical fibres, so that there are no external electrical connections. Optical fibres of two different types are used, polymer fibres to detect the angular error and glass fibre bundles to convey light power. 174 AN 3911704. AU Lorenz-R-D. Zik-J-J. Sykora-D-J. IN Wisconsin Univ., Madison, WI, USA. TI A direct-drive, robot parts, and tooling gripper with high-performance force feedback control. SO IEEE Transactions on Industry Applications. vol.27, no.2. pp. 275-81. March-April 1991. YR 1991. RN CCCC: 0093-9994/91/0300-0275$01.00. AB The authors present the design of a direct-drive parts and tooling gripper for use in robotic assembly operations. The gripper design incorporates three-dimensional force vector sensing and both force and position control with extremely-low-friction, direct linear motor drives. The authors present a state-variable approach to force control and discuss the design techniques required for a manipulator to achieve high-performance force control. They introduce an underlying principle in force control by demonstrating that the contact stiffness between the environment and the manipulator must be known and of an optimum range to provide good force control. To verify the techniques, a servo-controlled manipulator with compliant vector force sensing was developed. The manipulator features direct-drive, linear motors and compliant, vector force sensors. Force resolution was optimized by eliminating friction sources. Inertia was kept to a minimum to allow command following performance. A compliant vector force sensor provides the known contact stiffness between the manipulator and the workpiece environment. Experimental results show that force sensor stiffness is a key element in force loop control design and that robust force control dynamics are comparable to robust position control loop dynamics. 175 AN 3908099. AU Wen-J-T. Murphy-S. IN Rennselaer Polytech. Inst., Troy, NY, USA. TI Stability analysis of position and force control problems for robot arms. SO Published by: American Autom. Control Council. Green Valley, AZ, USA. 1990. CT Proceedings of the 1990 American Control Conference (IEEE Cat. No.90CH2896-9). San Diego, CA, USA. pp. 2806-11 vol.3. American Autom. Control Council. 23-25 May 1990. YR 1990. AB Stability issues involving the control of a robot arm under the influence of external forces are discussed. Several different scenarios are considered: position control with the external force as an unmodeled disturbance, compliant control for a bounded external force in some subspace, and compliant control for a force due to the interaction with an environment whose dynamical behavior can be modeled. In each of these cases, a stability analysis using the Lyapunov method is presented. An explanation of instability is put forth for the case in which the environment has flexibility and the gains are inappropriately chosen. When the environment is stiff in the force control subspace, robust stability can be achieved with the integral force feedback. 176 AN 3906670. AU Noritsugu-T. Wada-T. Shigeyoshi-M. IN Fac. of Eng., Okayama Univ., Japan. TI Compliance control of a pneumatic robot with improved sliding mode control method. SO Transactions of the Society of Instrument and Control Engineers. vol.27, no.1. pp. 77-84. Jan. 1991. YR 1991. RN CCCC: TR0001/91/2701-0077. AB An active compliance control method of a pneumatic robot is considered. A compliance control system regulates the relation between the manipulator position and the contact force along each task axis. This study proposes a position-based compliance control system which has a minor position control loop inside a force feedback loop. This position control loop dominates the overall compliance control performance. Unfortunately, a pneumatic robot cannot easily provide the high position control performance with usual control schemes owing to the low stiffness and the high nonlinearities. To overcome this problem, a sliding mode control scheme with a pressure feedback compensation is adopted in the position control loop. This compensation is effective to inhibit the chattering. The proposed compliance control method is applied experimentally to a pneumatic robot comprising two arms performing tracking control on constrained wall. stability and accuracy are examined. 177 AN 3901713. AU Wen-J-T. Murphy-S. IN Dept. of Electr., Comput. & Syst. Eng., Rensselaer Polytech. Inst., Troy, NY, USA. TI Stability analysis of position and force control for robot arms. SO IEEE Transactions on Automatic Control. vol.36, no.3. pp. 365-71. March 1991. YR 1991. RN CCCC: 0018-9286/91/0300-0365$01.00. AB Stability issues involving the control of a robot arm under the influence of external forces are discussed. Several different scenarios are considered: position control with the external force as an unmodeled disturbance, compliant control for a bounded external force in some subspace, and compliant control for a force due to the interaction with an environment whose dynamical behavior can be modeled. In each of these cases, a stability analysis using the Lyapunov method is presented. An explanation of instability is suggested in the case that the environment has flexibility and the gains are inappropriately chosen. When the environment is stiff in the force control subspace, robust (in time delay) stability can be achieved via the integral force feedback. However, the integral feedback gain should be chosen sufficiently small to account for possible flexibility in the system. 178 AN 3897843. AU Henrion-W. DiSanza-L. Ip-M. Terry-S. Jerman-H. TI Wide dynamic range direct accelerometer. SO Published by: IEEE. New York, NY, USA. 1990. CT Technical Digest. IEEE Solid-State Sensor and Actuator Workshop (Cat. No.90CH2783-9). Hilton Head Island, SC, USA. pp. 153-7. IEEE. 4-7 June 1990. YR 1990. RN CCCC: CH2783-9/90/0000-0153-7$1.00. AB The acceleration input-digital-output sigma-delta modulator accelerometer and the finite-element analysis of the mechanical structure are described. The performance obtained from prototype units is also presented. Silicon micromachining techniques were used to fabricate a high-precision, micro-gee accelerometer. Operating in a closed-loop configuration, the accelerometer utilizes electrostatic field sensing and electrostatic force feedback. The sensor assembly consists of three silicon chips, bonded together at the wafer level. The micromachined sensor is operated in a vacuum to eliminate nonlinear viscous damping and to provide a high-Q second-order mechanical resonant circuit. Near-critical damping is provided by the closed-loop control system. The control system is a highly oversampled sigma-delta modulator that produces a wide dynamic range and a direct digital output. These accelerometers can be built to serve widely diverse markets at a reasonable cost. Frequency ranges from DC to thousands of hertz, accelerations from nano-gees to hundreds of gees, and dynamic ranges in excess of 120 dB can all be accommodated in small rugged silicon accelerometers. 179 AN 3896034. AU Joyce-S-A. Houston-J-E. IN Sandia Nat. Labs., Albuquerque, NM, USA. TI A new force sensor incorporating force-feedback control for interfacial force microscopy. SO Review of Scientific Instruments. vol.62, no.3. pp. 710-15. March 1991. YR 1991. RN CCCC: 0034-6748/91/030710-06$02.00. AB An interfacial-force microscope capable of measuring the forces between two surfaces over the entire range of surface separations, up to contact, is described. The design is centered around a differential-capacitance displacement sensor where the common capacitor plate is supported by torsion bars. A force-feedback control system is incorporated which balances the interfacial forces at the sensor, maintaining the common capacitor plate at its rest position. This control therefore eliminates the instability or 'jumping' which occurs with conventional cantilever-based force sensors when the attractive force gradient between the fixed sample and sensor exceeds the mechanical stiffness of the cantilever. The operating characteristics of the sensor and its ability to measure interfacial forces using the feedback control at surface separations smaller than this instability point are demonstrated. 180 AN 3896033. AU Miller-G-L. Griffith-J-E. Wagner-E-R. Grigg-D-A. IN AT&T Bell Labs., Murray Hill, NJ, USA. TI A rocking beam electrostatic balance for the measurement of small forces. SO Review of Scientific Instruments. vol.62, no.3. pp. 705-9. March 1991. YR 1991. RN CCCC: 0034-6748/91/030705-05$02.00. AB There exists interest in the measurement of small forces for applications such as microtopography of semiconductor devices and atomic force microscopy. A new method is introduced in which a small silicon beam, that is acted on by the external force of interest, has its position sensed by an RF phase shift technique. The position information in turn is fed back via electrostatic forces to continuously rebalance the beam about its central support. This force-feedback approach provides high sensitivity, submillisecond response, inherent force calibration, and electronically controlled stiffness. 181 AN 3886640. AU Asada-H. IN Center for Inf.-Driven Mech. Syst., MIT, Cambridge, MA, USA. TI Teaching and learning of compliance using neural nets: representation and generation of nonlinear compliance. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1990. CT Proceedings 1990 IEEE International Conference on Robotics and Automation (Cat. No.90CH2876-1). Cincinnati, OH, USA. pp. 1237-44 vol.2. IEEE. 13-18 May 1990. YR 1990. RN CCCC: CH2876-1/90/0000-1237$01.00. AB A new approach to the representation and learning of compliance control laws using neural networks is presented. Compliance is treated as a nonlinear mapping from a measured force to a corrected motion. The nonlinear mapping is represented by a multilayered neural network, which makes it possible to deal with complex strategies of force feedback. This network representation provides not only linear compliance, as represented by stiffness and damping matrices, but also nonlinear compliance, which has never been explored extensively. This network approach also makes it possible to teach a desired compliance from teaching data by using an iterative learning algorithm. Conventional methods of compliant motion control are reviewed, linear compliance and its limits are discussed, and nonlinear compliance based on the network representation is introduced. An analysis is made of the nonlinearity of compliance that arises in performing assembly tasks, and the network structure that meets the requirements for representing a group of nonlinear compliances necessary for performing the assembly tasks is obtained. 182 AN 3885225. AU Noritsugu-T. Wada-T. Asanoma-T. IN Fac. of Eng., Okayama Univ., Japan. TI Impedance control of a pneumatic servo system with adaptive control method. SO Transactions of the Society of Instrument and Control Engineers. vol.26, no.12. pp. 1414-20. Dec. 1990. YR 1990. AB Pneumatic servos have relatively high compliance due to the air compressibility. To control them, an impedance control concept is suggested. The impedance of the overall control system depends not only on the manipulator but also on the manipulated object, of which the characteristics are usually unknown. Therefore, to attain the desired impedance over extensive operating conditions an adaptive control strategy is required. This paper proposes a method using a position-based approach where an adaptive position control system is constructed inside the force feedback loop. The proposed method is applied to an experimental pneumatic servo system comprising a pneumatic cylinder, electro-pneumatic proportional control valves and a spring object. It is found that both static stiffness and dynamic impedance of the pneumatic servo system can be independently regulated by setting a desired reference model. The impedance can be held constant for changes in system parameters such as object stiffness. Further, the instability problem for the low stiffness setting can be overcome by setting the high damping in the reference model. 183 AN 3883248. AU Waibel-B-J. Kazerooni-H. IN Waibel Tech. Comput., Newark, DE, USA. TI Theory and experiments on the stability of robot compliance control. SO IEEE Transactions on Robotics and Automation. vol.7, no.1. pp. 95-104. Feb. 1991. YR 1991. RN CCCC: 1042-296X/91/0200-0095$01.00. AB The authors present a nonlinear stability analysis for constrained robotic motion, a maneuver where the manipulator contacts the environment. The external disturbances, sensor noises, parameter uncertainties, and the dynamics of the total system composed of the robot and the environment have been modeled. The control of the manipulator is divided into two components: a computed torque trajectory controller that regulates the robot position and a compliance controller that modulates contact forces. Three sufficient conditions for stability have been derived. The first condition guarantees the stability of the system of robot and finite stiff environment when no force sensor and, consequently, no force feedback is considered for the system. The second condition guarantees stability of the robot and environment when a compliance compensator (operating on the contact force) supplements the trajectory controller. The third stability criterion shows that, for a robot contacting a very stiff environment, the gain of the compliance compensator must vary in inverse proportion to the gain of the trajectory compensator. 184 AN 3879113. AU Iwata-H. IN Inst. of Eng. Mech., Tsukuba Univ., Ibaraki, Japan. TI Artificial reality and simulator. SO Journal of the Japan Society for Simulation Technology. vol.9, no.4. pp. 238-48. Dec. 1990. YR 1990. AB Artificial reality is a configuration of a human interface presenting a computer-generated virtual world to sense organs such as eyes, ears, skins, and so on. The major objective of artificial reality is to amplify human intelligence by natural communication between computer and human being. The paper presents a brief history of artificial reality and topics of force display and virtual space walking systems. Force display is a virtual space operation system, combining real-time computer graphics and force feedback device. The paper describes issues of artificial reality technology and examples of developed systems. Expected application areas and future direction are discussed. 185 AN 3863667. AU Ahmad-S. Lee-C-N. IN Sch. of Electr. Eng., Purdue Univ., West Lafayette, IN, USA. TI Shape recovery from robot contour-tracking with force feedback. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1990. CT Proceedings 1990 IEEE International Conference on Robotics and Automation (Cat. No.90CH2876-1). Cincinnati, OH, USA. pp. 447-52 vol.1. IEEE. 13-18 May 1990. YR 1990. RN CCCC: CH2876-1/90/0000-0447$01.00. AB A process for shape recovery from robot contour-tracking operations with force feedback is described. Shape recovery is an important task for self-teaching robots and for exploratory operations in unknown environments. An algorithm which directs a position controlled robot around an unknown planar contour using the steady-state contact force information is described. A compensation process is explored for purposes of planar shape recovery. It is found through experimentation that the joint compliance is most conveniently compensated for in practice. Improvements in the shapes recovered from robot contouring are seen with the compensations. Experimental details and difficulties are also discussed. 186 AN 3863643. AU Liu-L. Ulrich-B-J. Elbestawi-M-A. IN Dept. of Mech. Eng., McMaster Univ., Hamilton, Ont., Canada. TI Robotic grinding force regulation: design, implementation and benefits. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1990. CT Proceedings 1990 IEEE International Conference on Robotics and Automation (Cat. No.90CH2876-1). Cincinnati, OH, USA. pp. 258-65 vol.1. IEEE. 13-18 May 1990. YR 1990. RN CCCC: CH2876-1/90/0000-0258$01.00. AB The design and implementation of force control for robotic rigid disk grinding are described. Experiments were conducted using a PUMA 762/VAL II industrial robot equipped with a 4-hp pneumatic grinder and a JR/sup 3/ force sensor. An external, 386-based host microcomputer, communicating with VAL II online, performs the force control algorithm calculations. The robotic grinding force model used was an experimentally verified analytic model. It was found that the grinding forces are very sensitive to the robot arm stiffness. Also, the end-effector path tracking errors, caused by the limited accuracy of the PUMA robot, significantly affect the grinding forces. The experimental results show, however, that a finely tuned PID force-feedback controller is able to maintain the grinding forces at a specified value. It can effectively compensate for force errors caused by both step force disturbances and robot path-tracking errors. The benefits of such force control are demonstrated by improved profiles of finished workpieces. 187 AN 3863642. AU Wen-J-T. Murphy-S. IN Dept. of Electr., Comput. & Syst. Eng., Rensselaer Polytech. Inst., Troy, NY, USA. TI Stability analysis of position and force control problems for robot arms. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1990. CT Proceedings 1990 IEEE International Conference on Robotics and Automation (Cat. No.90CH2876-1). Cincinnati, OH, USA. pp. 252-7 vol.1. IEEE. 13-18 May 1990. YR 1990. RN CCCC: CH2876-1/90/0000-0252$01.00. AB A stability analysis for robot manipulators under the influence of external forces is presented. Several control objectives are considered: rejecting the external force as a source of disturbance, complying to the external force as a generalized mass-spring-damper system, and actively controlling the external force when a dynamic model for the environment is available. An explanation of instability is given for the case in which the environment has flexibility and the gains are inappropriately chosen. When the environment is stiff in the force control subspace, robust stability can be achieved via the integral force feedback. 188 AN 3863641. AU Elosegui-P. Daniel-R-W. Sharkey-P-M. IN Dept. of Eng. Sci., Oxford Univ., UK. TI Joint servoing for robust manipulator force control. SO Published by: IEEE Comput. Soc. Press. Los Alamitos, CA, USA. 1990. CT Proceedings 1990 IEEE International Conference on Robotics and Automation (Cat. No.90CH2876-1). Cincinnati, OH, USA. pp. 246-51 vol.1. IEEE. 13-18 May 1990. YR 1990. RN CCCC: CH2876-1/90/0000-0246$01.00. AB An experimental and theoretical comparison is made of force control performance with different types of innerloop joint servoing techniques. The problem of disturbance rejection and sensitivity to plant dynamics variations (robustness) is addressed. Position, velocity, strain gauge derived joint torque, and current servos are designed and implemented on a specially instrumented industrial robot, and the end-effector force feedback performances achieved are compared. Joint strain derived torque servoing is found to provide the best overall robust force control performance. Experimental results of the robust hard-on-hard contact achieved with the novel force controller implementation based on joint torque sensing are provided. Conclusions are drawn on the force control performance achievable on a geared robot given the joint servoing technique. 189 AN 3823236. AU Spain-E-H. IN Adaptive Syst. Branch, Naval Ocean Syst. Center, Kailua, HI, USA. TI Stereo advantage for a peg-in-hole task using a force-feedback manipulator. SO Proceedings of the SPIE - The International Society for Optical Engineering. vol.1256. pp. 244-54. 1990. CT Stereoscopic Displays and Applications. Santa Clara, CA, USA. SPIE. SPSE. 12-14 Feb. 1990. YR 1990. AB An improved assessment methodology has been implemented at NOSC and tested using an instrumented peg-in-hole (PiH) taskboard. Several aspects of the methodology are discussed in light of their implications for future studies of manipulator performance. Using a simple (but high-fidelity) force-feedback manipulator, a group of nine trained operators showed a consistent advantage for stereoscopic TV viewing over monoscopic TV viewing when performing the PiH task. To introduce a controlled element of spatial uncertainty into the testing procedure, taskboard orientation relative to the manipulator and remote video camera head was changed in a randomized order on a trial-by-trial basis. The stereoscopic advantage demonstrated by this study can reasonably be expected to be even more pronounced as the quality of the stereo TV interface is improved and force-feedback provided through the manipulator system is diminished and/or distorted. 190 AN 3819108. AU Taejun-Um. Jisup-Yoon. Wootae-Jung. Jaesol-Lee. IN Korea Adv. Energy Res. Inst., Seoul, South Korea. TI Enhancement of electromechanical manipulator performance by external sensory feedback. SO Transactions of the American Nuclear Society. vol.62. pp. 595-6. 1990. CT 1990 Winter Meeting of the American Nuclear Society (papers in summary form only received). Washington, DC, USA. 11-15 Nov. 1990. YR 1990. AB The electromechanical manipulator (EMM) is widely used in nuclear facilities because of its strength and mechanical reliability. Nevertheless, the lack of internal position or force feedback makes it unsuitable for many tasks that require a high level of dexterity. At the remote handling department of Korea Atomic Energy Research Institute (KAERI), a series of research and development (R&D) activities was conducted to provide a higher degree of intelligence to the EMM with the aid of external sensory devices. These R&D activities focus on remote viewing and remote measurement in radioactive environments. As a result, an improved EMM system was achieved that incorporates various sensory devices such as a motion tracking system and a laser vision system. The authors present detailed technical descriptions of these sensors and test results. 191 AN 3800204. AU Bergamasco-M. Dario-P. Sabatini-A. Edited by: Kim-Y. Spelman-F-A. IN Scuola Superiore S. Anna, Pisa, Italy. TI Advanced interfaces for teleoperated biomedical robots. SO Published by: IEEE. New York, NY, USA. 1989. CT Images of the Twenty-First Century. Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society (Cat. No.89CH2770-6). Seattle, WA, USA. pp. 912-13 vol.3. IEEE. 9-12 Nov. 1989. YR 1989. RN CCCC: CH2770-6/89/0000-0912$01.00. AB General considerations are presented for the use of advanced interfaces for teleoperating robots capable of performing medical/surgical procedures. The authors point out that the design of a device that could allow the surgeon to command robot motion and force and to receive from the robot the sensory information about the external environment is strictly related to: (1) the availability of a sensorized dexterous end-effector as a slave device; (2) the ability of the master operator to control the robotic end-effector in the most natural way, i.e. by performing the same movements required in a real situation; and (3) the availability, on the master device, of components able to recreate for the human operator the sensory information acquired by the remote sensory systems. An instrumented glove able to transmit to the human operator kinesthetic force feedback and tactile feedback is presented. 192 AN 3800196. AU Sabatini-A-M. Bergamasco-M. Dario-P. Edited by: Kim-Y. Spelman-F-A. IN Scuola Superiore di Studi, Pisa Univ., Italy. TI Force feedback-based telemicromanipulation for robot surgery on soft tissues. SO Published by: IEEE. New York, NY, USA. 1989. CT Images of the Twenty-First Century. Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society (Cat. No.89CH2770-6). Seattle, WA, USA. pp. 890-1 vol.3. IEEE. 9-12 Nov. 1989. YR 1989. RN CCCC: CH2770-6/89/0000-0890$01.00. AB In order to investigate basic problems in the use of robots for surgical applications, an experimental testbed aimed at performing tasks requiring fine control of force and movement such as cutting a soft tissue was developed. Preliminary results obtained with the present version of the robot system confirm the importance of tactile and force sensing capabilities in order to perform tasks potentially useful for surgical applications. Tactile sensing detects features of the material to be cut which can be useful in planning cutting strategies. As for force sensing, the adopted control strategy requires a force feedback from the slave finger sensors to inform the master on the progress of the operation: this feedback signal can be used to counteract the movements of the stick. 193 AN 3799649. AU Asada-H. Hirai-S. Edited by: Miura-H. Arimoto-S. IN MIT, Cambridge, MA, USA. TI Towards a symbolic-level force feedback: recognition of assembly process states. SO Published by: MIT Press. Cambridge, MA, USA. 1990. CT Robotics Research. Fifth International Symposium. Tokyo, Japan. pp. 341-6. 28-31 Aug. 1989. YR 1990. AB A model-based approach to the in-process monitoring of assembly operations is presented. Force and displacement information acquired in the process is interpreted by using geometric models of assembly parts in order to estimate the state of the assembly process. In particular, the system is capable of monitoring the contact state at which the assembly parts are contacting each other. Based on geometric models, the authors derive a type of pattern classifiers by which the system can determine the contact state from sensory information such as force and displacement. The classifiers of the contact state are formulated by use of the theory of polyhedral convex cones, which allows one to treat nonholonomic geometric constraints in a systematic manner. 194 AN 3795186. AU Borovoi-A-V. TI Stability of a manipulator with force feedback. SO Izvestiya Akademii Nauk SSSR, Mekhanika Tverdogo Tela. vol.25, no.1. pp. 37-44. 1990. TR Mechanics of Solids. vol.25, no.1. pp. 37-45. 1990. YR 1990. 1990. RN CCCC: 0025-6544/90/$20.00. AB Considers a model of a manipulator with feedback based on position, the speed of the working element, and the deformation of the force sensor. The model takes account of the mass of the working element, and also the delay in the amplifier of the electric drive. A steady-state solution is obtained for the case of programmed motion with constant velocity. Stability of the given steady-state solution in the region of feedback parameters and the coefficient of elasticity of the force sensor is investigated analytically. 195 AN 3792057. AU Purnell-G. Maddock-N-A. Khodabandehloo-K. IN Dept. of Mech. Eng., Bristol Univ., UK. TI Robot deboning for beef forequarters. SO Robotica. vol.8, pt.4. pp. 303-10. Oct.-Dec. 1990. YR 1990. AB Initial development of a vision-aided robotic meat cutting system based on force feedback control and continuous path planning is described. Forequarter beef cutting is attempted where each carcass processed is compared to a database containing cut information from previously processed beef carcasses. Using the database information, cut start and end points can be defined along with initial path direction for each cut. A robot then drives a powered knife through the carcass utilising force feedback control to follow bone profiles, thus removing meat from the forequarter. An original cutting scheme suitable for robotic butchery of a beef forequarter is defined, along with a notation scheme for describing the cutting procedures. 196 AN 3791402. AU Iwata-H. IN Inst. of Eng. Mech., Tsukuba Univ., Ibaraki, Japan. TI Artificial reality with force-feedback: development of desktop virtual space with compact master manipulator. SO Computer Graphics. vol.24, no.4. pp. 165-70. Aug. 1990. CT SIGGRAPH 1990. 17th Annual ACM Conference on Computer Graphics and Interactive Techniques. Dallas, TX, USA. ACM. IEEE. 6-10 Aug. 1990. YR 1990. RN CCCC: 0097-8930/90/008/0165$00.75. AB A configuration for a human interface for artificial reality is discussed. The paper describes a method of implementing force-feedback in a virtual space manipulation system. The system is composed of two subsystems, a real-time graphic display system and a tactile input device with reaction force generator. A specialized graphics computer (Stardent TITAN) provides a real-time image of the virtual space. A 9 degree-of-freedom manipulator has been developed as a tactile input device. The manipulator applies reaction forces to the fingers and palm of the operator. The generated forces are calculated from a solid model of the virtual space. The performance of the system is exemplified in manipulation of virtual solid objects such as a mockup for industrial design and a 3D animated character. 197 AN 3768356. AU Kircanski-N. Timcenko-A. Vukobratovic-M. IN Mihailo Pupin Inst., Belgrade, Yugoslavia. TI Position control of robot manipulators with elastic joints using force feedback. SO Journal of Robotic Systems. vol.7, no.4. pp. 535-54. Aug. 1990. YR 1990. RN CCCC: 0741-2223/90/040535-20$04.00. AB Transmission flexibility, as a predominant source of mechanical resonance, often results in inaccurate tracking of prescribed robot trajectories. Thus, the control algorithm must compensate not only for nonlinear dynamics of the arm and payload variations, but also for resonant effects in joints. The compensation for all of these effects results in a very complicated control algorithm which are difficult to apply in practice. The authors suggest the measurement of torque/force on the output shaft of the elastic reducer in order to compensate for elastic effects. The torque measurement can be replaced by the simultaneous measurement of the joint and the motor-shaft angle. Then, they introduce a dynamic compensator with two zeros and two poles to filtrate the torque signal. It appears that the obtained control law is very simple and compensates for nonlinear system dynamics, variable payload parameters and resonant effects in joints. The proposed control scheme is illustrated by computer simulation of a six-degree-of-freedom robot. 198 AN 3764180. AU Hollis-R-L. Salcudean-S. Abraham-D-W. IN IBM Thomsas J. Watson Res. Center, Yorktown Heights, NY, USA. TI Toward a tele-nanorobotic manipulation system with atomic scale force feedback and motion resolution. SO Published by: IEEE. New York, NY, USA. 1990. CT Proceedings. IEEE Micro Electro Mechanical Systems. An Investigation of Micro Structures, Sensors, Actuators, Machines and Robots (Cat. No.90CH2832-4). Napa Valley, CA, USA. pp. 115-19. IEEE. 11-14 Feb. 1990. YR 1990. RN CCCC: CH2832-4/90/0000-0115$01.00. AB Steps toward the realization of a tele-nanorobotic manipulation system using a magnetically levitated hand controller coupled with a scanning tunneling microscope are discussed. With this system, it is possible to 'manually' probe surfaces at atomic scale, while 'feeling' the atomic-scale topography back in the operator's hand. Results for sputtered gold and graphite are presented. 199 AN 3727506. AU Tao-J-M. Luh-J-Y-S. Zheng-Y-F. IN Dept. of Electr. & Comput. Eng., Clemson Univ., SC, USA. TI Compliant coordination control of two moving industrial robots. SO IEEE Transactions on Robotics and Automation. vol.6, no.3. pp. 322-30. June 1990. YR 1990. RN CCCC: 1042-296X/90/0600-0322$01.00. AB When two robots execute coordinated motion in industrial application such as assembly, not only is the specification of the desired motion of each robot's end effector required, but also that of the desired contact force exerted on the end effectors. The involvement of the forces is the motivation for a consideration of compliance. The compliant coordination control scheme of two moving robots is presented. One robot is equipped with a force/torque sensing wrist, which provides force feedback signals and permits the fine coordinated motion control of complex assembly tasks. A control strategy is derived so that the measured force/torque can be used to modify the trajectory of one of the robots. This control scheme can be realized in real time by using the proposed computational structure. The system stability is related to the force-displacement conversion gain in the forward path. An experiment that screws a moving nut onto a moving bolt has been carried out as an illustration. 200 AN 3724366. AU Lorenz-R-D. Meyer-K-M. Van-De-Riet-D-M. IN Dept. of Mech. Eng. & Comput. Eng., Wisconsin Univ., Madison, WI, USA. TI A novel, compliant, four degree-of-freedom, robotic fingertip sensor. SO IEEE Transactions on Industry Applications. vol.26, no.4. pp. 613-19. July-Aug. 1990. YR 1990. RN CCCC: 0093-9994/90/0700-0613$01.00. AB A novel, low-cost, compliant fingertip sensor for robotic gripper applications is presented. The fingertip sensor is intended for use in grippers where force feedback information is needed, such as in clean room or space applications where telerobotic operation is desired. The fingertip is approximately the size of the thumb of an adult male and is approximately as compliant as human flesh. The sensor was designed to optimize the sensitivity to four components of force/torque: the normal force, both tangential force terms, and the torque about the normal axis. Finite-element analysis was used to optimize the shape of the fingertip and the location/size of the polyvinylidene fluoride (PVDF) film piezoelectric sensing elements. The design analysis and the experimental results from evaluation of the prototype robot fingertip sensors are presented. 201 AN 3707404. AU Pertin-Troccaz-J. IN LIFIA/IMAG-CNRS-Lab., Grenoble, France. TI Automation of grasp planning for a dextrous hand. SO Published by: IEE. London, UK. 1990. CT IEE Colloquium on 'High-Tech Help for the Handicapped' (Digest No.054). London, UK. pp. 6/1-3. IEE. 2 April 1990. YR 1990. AB An approach is presented for the automatic preshaping of a dextrous multifingered hand. Due to the high number of degrees of freedom, it is impossible to build and to explore the whole set of possible configurations of the gripper in order to choose a single way of grasping compatible with the object shape, as it is classically done for simple parallel jaws grippers. Research in neurophysiology has shown that during the reaching of an object, the human hand preshapes in order to prepare the matching between the hand and object shapes; a preshape represents a class of configurations, among which the exact grasping configuration is chosen from tactile and force feedback coming from the fingers at grasping time. The problem is studied for three types of preshape, the encompassing preshape, the precision preshape and the lateral preshape. 202 AN 3706659. AU Buzan-F-T. Sheridan-T-B. IN MIT, Cambridge, MA, USA. TI A model-based predictive operator aid for telemanipulators with time delay. SO Published by: IEEE. New York, NY, USA. 1989. CT 1989 IEEE International Conference on Systems, Man and Cybernetics. Conference Proceeding. (Cat. No.89CH2809-2). Cambridge, MA, USA. pp. 138-43 vol.1. IEEE. 14-17 Nov. 1989. YR 1989. RN CCCC: CH2809-2/89/0000-0138$01.00. AB A dynamic user aid was developed to help operators compensate for several-second time delays in telemanipulator systems. The approach includes state prediction, position feedback presentation, force feedback presentation, and slave impedance control. The aid helps the operator anticipate the delayed system response by providing predicted force and position feedback using dynamic models of both the manipulator and the environment. Three predictive force feedback techniques are also presented. Results of tests with a single-degree-of-freedom simulation showed operator performance to improve with the predictive aid. Tests also showed that 'dual' force reflection provides better performance than other techniques. 203 AN 3706658. AU Hannaford-B. Kim-W-S. IN Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA. TI Force reflection, shared control, and time delay in telemanipulation. SO Published by: IEEE. New York, NY, USA. 1989. CT 1989 IEEE International Conference on Systems, Man and Cybernetics. Conference Proceeding. (Cat. No.89CH2809-2). Cambridge, MA, USA. pp. 133-7 vol.1. IEEE. 14-17 Nov. 1989. YR 1989. RN CCCC: CH2809-2/89/0000-0133$01.00. AB Time delays of between 2 ms and 4096 ms were introduced between master and slave manipulators in advanced 6-DOF (degrees-of-freedom) force-reflecting telemanipulation system. The effects of the imposed delay were quantified in terms of completion time (CT) and sum-of-squared-force (SOSF) with six test operators and two modes of control: kinesthetic force feedback (KFF) and shared compliant control (SCC). KFF applies forces and torques proportional to those sensed by the slave robot to the human operator through the master. SCC uses the force/torque information entirely at the slave side to implement a variation on impedance control in parallel with the operator's position commands. Experiments measured effects of human operator grasp variation on stability of contact with KFF. CT and SOSF performance in a peg-in-hole task decreased linearly with imposed time delay using KFF, and decreased at a lower rate with SCC. SCC enabled task performance for 2 and 4 second delays, critical values for low-earth-orbit applications. 204 AN 3702579. AU Inoue-M. Yamada-K. Tanaka-K-I. Nakagawa-J. Machida-K. Toda-Y. IN Mitsubishi Elect. Corp., Hyogo, Japan. TI Six-axis bilateral control of an articulated slave manipulator using a Cartesian master manipulator. SO Advanced Robotics. vol.4, no.2. pp. 139-50. 1990. YR 1990. AB A bilateral master-slave manipulator system with different kinematics is described. In order to obtain good manoeuvrability, it is required to reduce the computational time for coordinate transformation and data communication between the master and the slave. The authors propose methods for improving the performance: (1) the joints of the master manipulator are arranged along a Cartesian coordinate frame and force-control using a force/torque sensor in the handle; (2) the attitude of the hand or handle of the manipulators is described by quaternions; and (3) a dual CPU system connected by a serial communication line is used. A system that employs these methods realizes smooth operation and precise force feedback. 205 AN 3685174. AU Wang-D. McClamroch-N-H. IN Dept. of Electr. Eng., Nan Yang Technol. Inst., Singapore. TI Position/force control design for constrained mechanical systems: Lyapunov's direct method. SO Published by: IEEE. New York, NY, USA. 1989. CT Proceedings of the 28th IEEE Conference on Decision and Control (Cat. No.89CH2642-7). Tampa, FL, USA. pp. 1665-9 vol.2. IEEE. 13-15 Dec. 1989. YR 1989. RN CCCC: CH2642-7/89/0000-1665$01.00. AB A design procedure for simultaneous position/force control is developed, using Lyapunov's direct method for mechanical systems with holonomic constraints. Many mechanical systems which interact with their environment require the effects of these constraints to be taken into account in the control design. The force applied by the constraint plays a critical role in constrained motion and is, along with displacements and velocities, to be regulated at specified values. Lyapunov's direct method is used to develop a class of decentralized position/force controllers. The approach avoids coordinate transformation and does not require force feedback. The conditions for gain selection demonstrate the importance of the constraints. An example is used to demonstrate this control design method; closed-loop characteristics are indicated by computer simulations. 206 AN 3648803. AU Yoshida-Y. Yabuki-A. Nakata-Y. Nishimoto-K. IN Fujitsu Lab. Ltd., Kanagawa, Japan. TI High-speed force controller for SCARA robots. SO Published by: IEEE. New York, NY, USA. 1989. CT IECON '89. 15th Annual Conference of IEEE Industrial Electronics Society (Cat. No.89CH2795-3). Philadelphia, PA, USA. pp. 629-33 vol.3. IEEE. 6-10 Nov. 1989. YR 1989. RN CCCC: CH2795-3/89/0000-0629$01.00. AB The SCARA (selective compliance assembly robot arm) robot has horizontal compliance. However, the amount and direction of compliance must be controlled before the robot can be used in actual applications. The authors have developed an active compliance controller that uses force sensors on the wrists of the robot to determine the contact forces acting on the end effector. The sensors feed this information to the trajectory generator of the robot controller. The controller achieves high-speed control (the sampling time is 1 ms) by performing all control operations in parallel using two MB8764 digital signal processors. The stability of the control was analyzed for joints having an arm that is not rigid. The force control can be stabilized by keeping the force feedback gain reasonably small. 207 AN 3648438. AU Nagata-Y. Edited by: Yokoyama-Y. IN IBM Japan, Tokyo, Japan. TI Soft motion robot and its application. SO Published by: IFS Publications. Kempston, UK. 1989. CT Proceedings of the 10th International Conference on Assembly Automation. Kanazawa, Japan. pp. 199-206. Japan Soc. Mech. Eng. Soc. Instrum. Control Eng. Japan Ind. Robot Assoc. Soc. Manuf. Eng. et al. 23-25 Oct. 1989. YR 1989. AB Today, the requirement for industrial robot application to dextrous operation, such as precise insertion is increasing. Ordinary industrial robot is controlled by position feedback, therefore the robot cannot follow unexpected positional change. In the worst case, misalignment of parts causes parts damage. The author has developed a practical compliance controlled robot (soft motion robot) using force feedback. This robot can move softly and delicately like a human hand, in order to absorb shock of collision between two objects of insertion. The paper explains the soft motion robot and its application for connector insertion in the automated manufacturing line. 208 AN 3640740. AU Gorinevsky-D-M. Shneider-A-Yu. IN Inst. for Problems of Inf. Transmission, Acad. of Sci., Moscow, USSR. TI Force control in locomotion of legged vehicles over rigid and soft surfaces. SO International Journal of Robotics Research. vol.9, no.2. pp. 4-23. April 1990. YR 1990. AB The control system of the hexapod walking vehicle, designed at the Institute for Mechanics at Moscow State University and at the Institute for Problems of Information Transmission at the USSR Academy of Sciences, is extended to effect the control of foot-contact forces and locomotion in soft soil. The previously developed positional control system enables the computation of commanded motion of the vehicle legs and positional feedback to track this commanded motion. Force feedback is added to the control system, in addition to computation of commanded forces and leg position corrections for leg sinkage during soft soil locomotion. A number of algorithms are proposed to control vertical force components (loads on legs) and leg sinkage in locomotion in elastic and consolidating soils. In the latter case, which corresponds to most natural soils, the bearing properties of the surface are considered a priori unknown. The results of the experimental implementation of the algorithms are presented. 209 AN 3639996. AU Tae-Sang-Chung. TI A stability effect of passive compliance on active compliance control. SO Transactions of the Korean Institute of Electrical Engineers. vol.39, no.1. pp. 92-106. Jan. 1990. YR 1990. AB Active compliance is often used in the control of robot manipulators for the implementation of complex tasks such as assembly, multi-finger fine motion, legged-vehicle adaptive control, etc. This technique balances the interactive force between the manipulator tip and its working environment with its position and velocity errors to achieve the operation of a damped spring. The author investigates the effect of passive compliance on system stability with regard to force feedback implementation for actively compliant motion. Usually it is understood that accurate position control requires a stiff system. However, theoretical examination of control experiments on a legged suspension vehicle suggests that, if the control includes discrete-time force feedback, some passive compliance is necessary at the legs of the vehicle for system stability. A theoretical analysis, numerical simulation, and experimental result, confirming the above conclusion, are introduced. 210 AN 3624190. AU Lorenz-R-D. Zik-J-J. Sykora-D-J. IN Wisconsin Univ., Madison, WI, USA. TI A direct-drive, robot parts and tooling gripper with high performance force feedback control. SO Published by: IEEE. New York, NY, USA. 1989. CT Conference Record of the IEEE Industry Applications Society Annual Meeting (Cat. No.89CH2792-0). San Diego, CA, USA. pp. 1678-84 vol.2. IEEE. 1-5 Oct. 1989. YR 1989. RN CCCC: CH2792-0/89/0000-1678$1.00. AB The authors present the design of a direct-drive parts and tooling gripper for use in robotic assembly operations. The gripper design incorporates three-dimensional force vector sensing and both force and position control with extremely-low-friction, direct linear drives. The authors discuss a state-variable approach to force control and the design technique required for a manipulator to achieve high-performance force control. They demonstrate that stiffness of the contact between the environment and the manipulator must be known and of an optimum range to provide good force control. To verify the techniques, a servo-controlled manipulator with compliant vector force sensing was developed. The manipulator features direct-drive, linear motors and a compliant, vector force sensor. Force resolution was optimized by eliminating friction sources. A compliant vector force sensor provides the known contact stiffness between the manipulator and the workpiece environment. Experimental results show that force sensor stiffness is a key element in force loop control design and that robust force control dynamics is comparable to robust position control loop dynamics. 211 AN 3617083. AU Komada-S. Ohnishi-K. IN Dept. of Electr. Eng., Mie Univ., Japan. TI Force feedback control of robot manipulator by the acceleration tracing orientation method. SO IEEE Transactions on Industrial Electronics. vol.37, no.1. pp. 6-12. Feb. 1990. YR 1990. RN CCCC: 0278-0046/90/0200-0006$01.00. AB The authors propose a novel approach to force and compliance control of multi-degree-of-freedom (DOF) robot manipulators. The acceleration tracing orientation method (ATOM) is applied to both controllers. The control law is described in the Cartesian space; however, the final command is the acceleration in the joint space. The interactive terms in each joint disturb and deteriorate the joint motion. The disturbance observer cancels out the total sum of these terms and enables each joint to trace the acceleration command. As a result, a robust control is possible in the force task. The testing of the proposed system in a three-DOF robot manipulator is discussed. 212 AN 3615243. AU Pearce-C-H. IN Syst. & Equipment Div., BAe plc, Plymouth, UK. TI Microflex Attitude and Heading Reference System. SO Published by: IEE. London, UK. 1990. CT IEE Colloquium on 'Inertial Navigation Sensor Development' (Digest No.5). London, UK. pp. 4/1-3. IEE. 9 Jan. 1990. YR 1990. AB The author describes the Microflex attitude and heading reference system (MAHRS) which is an all attitude system that provides outputs of magnetic heading, pitch and roll attitude, aircraft body rates and accelerations, together with their associated validity status. It is a full strapdown system utilising two Microflex two axis rate gyroscopes, three force feedback linear accelerometers and a three axis magnetic sensor. The Microflex gyroscope provides a wide dynamic range from a few degrees/hr drift to in excess of 300 degrees/sec., by skewing the sensing axes, roll rates in excess of 400 degrees/sec can be measured. Each sensor provides two axes of rate information from a forced feedback closed loop system, that rate output being the analogue voltage developed by the torquer restoring current across a precision resistor. 213 AN 3556885. AU Fiori-N. Richardson-J. Bouin-M. Edited by: Mason-C-A. IN Paris Univ., France. TI The effects of varying force-feedback on performance and workload in a telemanipulation task. SO Published by: IFS Publications. Bedford, UK. 1988. CT Teleoperation and control 1988. Proceedings of the International Symposium. Bristol, UK. pp. 319-29. 12-15 July 1988. YR 1988. AB Recent developments in the design of teleoperators have provided the human operator with various functions aimed at reducing physical workload. In the paper, the possibility of modifying force-feedback and the ability to suppress the vertical force component on the manipulated object are studied. 214 AN 3556873. AU Sharpe-J-E-E. Edited by: Mason-C-A. IN Queen Mary Coll., London Univ., UK. TI Technical and human operational requirements for skill transfer in teleoperations. SO Published by: IFS Publications. Bedford, UK. 1988. CT Teleoperation and control 1988. Proceedings of the International Symposium. Bristol, UK. pp. 175-87. 12-15 July 1988. YR 1988. AB The development of the concepts of covariant bilateral control of robotic manipulation has enabled operators to control remote resonant loads, to operate systems with pure delays and perform with improved accuracy. The paper outlines the needs of skilled operation and the design of practical covariant bilateral systems that have been used to provide quantitative data on the performance of operators with and without force feedback. 215 AN 3554297. AU Kotter-W. IN Robert Bosch GmbH, Stuttgart, West Germany. TI Proportional electrohydraulic control of directional control valves for mobile applications. SO Oelhydraulik und Pneumatik. vol.33, no.11. pp. 862-7. Nov. 1989. YR 1989. AB Describes a new concept for position control using force feedback. The strength of electronics in mobile hydraulics lies in the auxiliary functions offered. In addition to the required input signal current for the pilot valves they also include safety circuits, interconnections with other functions and the elimination of undesirable characteristics associated with directional valves. Circuits using the electrohydraulic directional valves for energy-saving and rational operation are listed as examples. 216 AN 3531799. AU Merlet-J-P. TI Parallel manipulators part 3: applications. SO 99 pp. March 1989. YR 1989. RN 1003. Issuing organization: Inst. Nat. Recherche Inf. Autom., Le Chesnay, France. AB Considers the potential applications of parallel manipulators, especially those involving force-feedback control. The author deals with some features of this kind of manipulators which are important for their control. The author describes the programming environment developed, the hardware which has been used and its consequences upon the performances. The author introduces recent developments in the singular configuration theory presented in part two, especially the study of the eigenvectors yielding the motion of the manipulator in these configurations. 217 AN 3527142. AU Brown-D-B. Hemami-H. Istefanopulos-Y. IN Loral Defense Syst., Akron, OH, USA. TI On-line exploration of an unknown surface by a robotic probe. SO Journal of Robotic Systems. vol.6, no.5. pp. 521-43. Oct. 1989. YR 1989. RN CCCC: 0741-2223/89/050521-23$04.00. AB A control strategy is developed for a robotic probe with tactile sensing to explore an unknown surface without losing contact. Digital computer simulations are performed of a three-link, planar manipulator exploring an ellipsoidal surface in order to test the control strategy. The equations of motion are written and linear, time-varying, state-variable feedback is applied to stabilize and decouple the system. A tactile sensor is simulated to supply the normal force between the robot and the surface. From the magnitude and direction of this force, the desired trajectory is determined. An inverse plant and force feedback are implemented to provide the required input torques to the robot's actuators. 218 AN 3526765. AU Chiou-B-C. Shahinpoor-M. IN Dept. of Mech. Eng., New Mexico Univ., Albuquerque, NM, USA. TI Effect of joint stiffness on the dynamic stability of a one-link force-controlled manipulator. SO Robotica. vol.7, pt.4. pp. 339-42. Oct. 1989. YR 1989. AB Studies are the effects of joint flexibility on the dynamic stability of a one-link force-controlled manipulator. The closed-loop dynamic equation with the explicit force controller and the damping force controller are first derived. Stability analysis is then carried out by computing the system eigenvalues. Results indicate a conditionally stable system. Due to the presence of discontinuous contacts with the environment during the interaction process, the system exhibits a stable limit cycle when the force feedback gain goes beyond the critical value. 219 AN 3509185. AU Pribadi-K. Bay-J-S. Hemami-H. IN Lord & Co. Inc., Manassas, VA, USA. TI Exploration and dynamic shape estimation by a robotic probe. SO IEEE Transactions on Systems, Man and Cybernetics. vol.19, no.4. pp. 840-6. July-Aug. 1989. YR 1989. RN CCCC: 0018-9472/89/0700-0840$01.00. AB A strategy for motion of a planar manipulator on an unknown surface is presented. To estimate a parameter vector for the surface, least-squares estimators are formulated that use both the kinematic and dynamic data available online. The authors begin with the presentation of a control strategy that uses local sensory data to guide the end effector incrementally over the surface. Force feedback is given, which is later shown to be successful in the uninterrupted maintenance of contact. Motion over the unknown shape is justified by demonstrating that a simple shape estimation algorithm can converge to give a parametric description of the surface. Geometric and differential models of the surface are presented and the estimation procedure is specified. Also presented are the results of a number of computer simulations for a three-link planar manipulator moving over an ellipse whose parameters are unknown to the controller. It is found that, in the presence of noise, dynamic data degrade the estimates. 220 AN 3492182. AU Ostoja-Starzewski-M. Skibniewski-M. IN Purdue Univ., West Lafayette, IN, USA. TI A master-slave manipulator for excavation and construction tasks. SO Robotics and Autonomous Systems. vol.4, no.4. pp. 333-7. April 1989. YR 1989. RN CCCC: 0921-8890/89/$3.50. AB Currently used excavators and other construction machines use hydraulic actuators as the means of providing the necessary power to their effector tooling. The tools lack the flexibility of applying varying forces on an excavated object, thus preventing the use of powered equipment for the excavation and handling of buried sensitive objects. The prototype design of a master-slave force-feedback hydraulic manipulator described in the paper will enable equipment operators to 'feel' the force applied by the tool on a handled object as well as its location in space. This new tool may be provided as an optional feature on the traditional excavators, thus contributing to a greater flexibility of these machines and to the productivity enhancement of related work tasks. 221 AN 3471282. AU Hannaford-B. IN Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA. TI Stability and performance tradeoffs in bi-lateral telemanipulation. SO Published by: IEEE Comput. Soc. Press. Washington, DC, USA. 1989. CT Proceedings. 1989 IEEE International Conference on Robotics and Automation (Cat. No.89CH2750-8). Scottsdale, AZ, USA. pp. 1764-7 vol.3. IEEE. 14-19 May 1989. YR 1989. RN CCCC: CH2750-8/89/0000-1764$01.00. AB Kinesthetic force feedback provides measurable increase in remote manipulation system performance. Intensive computation time requirements or operation under conditions of time delay can cause serious stability problems in control-system design. The author presents a simplified linear analysis of this stability problem for the forward-flow generalized architecture and uses the hybrid two-port representation to express the loop gain of the traditional master-slave architecture, which can be subjected to similar analysis. The hybrid two-port representation is also used to express the effects on the fidelity of manipulation or feel of one design approach used to stabilize the forward-flow architecture. The results suggest that, when local force feedback at the slave side is used to reduce manipulator stability problems, a price is paid in terms of telemanipulation fidelity. 222 AN 3467236. AU Kanzaki-K. Kobayasi-N. Yamada-T. TI Compensation of transfer deviation on symmetry type bilateral servo mechanisms. SO Journal of the Japan Society of Precision Engineering. vol.55, no.4. pp. 754-60. April 1989. YR 1989. AB There are two types of the bilateral servo mechanisms utilized to move a reaction type manipulator. The simple symmetry type has the larger transfer deviation. The force feedback type with the smaller transfer deviation needs troublesome force sensing devices. The authors describe the simple compensation method of transfer deviation on the symmetry-type. It is found that the transfer deviation of the torque decreases by subtracting the output of the tachometer generator through a PD circuit from the driving input of the opposite motor. The system is unstable when the gain constants in compensation circuits are over the limits, which are decided to equivalent mechanical inertia moment and viscous damping factor. The transfer deviation of the compensated symmetry type system is near to that of the force feedback system. 223 AN 3452471. AU Munday-E-G. IN North Carolina Univ., Charlotte, NC, USA. TI Computer simulation of compliant motion control for a robotic arm. SO Published by: IEEE Comput. Soc. Press. Washington, DC, USA. 1989. CT Proceedings. The Twenty-First Southeastern Symposium on System Theory (Cat. No.89CH2714-4). Tallahassee, FL, USA. pp. 98-103. IEEE. FAMU/FSU Coll. Eng. 26-28 March 1989. YR 1989. RN CCCC: CH2714-4/89/0000-0098$01.00. AB A hybrid position force control scheme was used to simulate the control of a two-degree-of-freedom robotic arm. The contact force between the end-effector and a surface was controlled while the end-effector moved parallel to the surface under position control. The end-effector was modeled as having passive compliance. Five simulations were performed using different levels of random noise in the force feedback loop. Stability was achieved and significant force control was maintained, despite high levels of noise in the force feedback. 224 AN 3452410. AU Liu-L. Crago-P-E. Edited by: Harris-G. Walker-C. IN Dept. of Biomed. Eng., Case Western Reserve Univ., Cleveland, OH, USA. TI Simulation of hand grasp control by force and position feedback. SO Published by: IEEE. New York, NY, USA. 1988. CT Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society (IEEE Cat. No.88CH2566-8). New Orleans, LA, USA. pp. 1641-2 vol.4. IEEE. 4-7 Nov. 1988. YR 1988. RN CCCC: CH2566-8/88/0000-1641$01.00. AB A computer simulation of hand grasp control by force and position feedback has been implemented with a digital controller and a discrete-time muscle model. The simulated system consists of a stiffness controller, a pulse-width activation controller, a coactivation map, a flexor and an extensor muscle, and separate internal and external loads. The measured feedback quantities are the position and the contact force between the digit and the external load. In clinical use, the control system must perform well under a wide range of external loads and be robust to variation in muscle properties. The simulation is being used to study the system performance and to optimize tuning procedures to be used in the clinical setting. 225 AN 3451310. AU Youcef-Toumi-K. Gutz-D-A. IN Dept. of Mech. Eng., MIT, Cambridge, MA, USA. TI Impact and force control. SO Published by: IEEE Comput. Soc. Press. Washington, DC, USA. 1989. CT Proceedings. 1989 IEEE International Conference on Robotics and Automation (Cat. No.89CH2750-8). Scottsdale, AZ, USA. pp. 410-16 vol.1. IEEE. 14-19 May 1989. YR 1989. RN CCCC: CH2750-8/89/0000-0410$01.00. AB Robot manipulators and drive systems can experience instability or poor control performance after impacting with an environment. The authors present an analytical model for impact which is experimentally validated step-by-step. Extensive simulations and experiments are conducted to explain impact phenomena for the case of a force feedback control of a single-axis drive system. The experimental tests were conducted on a manipulator drive system which consists of a motor, a transmission, a link, a force sensor, and a movable environment. The results are based on an energy method and presented concisely in dimensionless form. To this end, a small number of dimensionless groups are used to characterize the impact behavior through simulations and tests. It is shown that integral force compensation with velocity feedback improves force tracking and reject impacts. It is also revealed that impact response can be tuned by selecting a favourable dimensionless ratio of force to approach velocity. 226 AN 3451309. AU Colgate-E. Hogan-N. IN Dept. of Mech. Eng., Northwestern Univ., Evanston, IL, USA. TI An analysis of contact instability in terms of passive physical equivalents. SO Published by: IEEE Comput. Soc. Press. Washington, DC, USA. 1989. CT Proceedings. 1989 IEEE International Conference on Robotics and Automation (Cat. No.89CH2750-8). Scottsdale, AZ, USA. pp. 404-9 vol.1. IEEE. 14-19 May 1989. YR 1989. RN CCCC: CH2750-8/89/0000-0404$01.00. AB The authors explore the sources of and solutions to robot contact instability associated with force feedback. The behavior of several linear robot models is analyzed in terms of the properties of their admittances. Using the novel technique of passive physical equivalents, an explanation for the often-observed instability of a force-controlled robot contacting a stiff surface is offered, and it is shown that a fundamental limit exists to the efficacy of any force feedback controller implemented on a robot with noncolocated actuators and sensors. Suggestions for improved force control involving both mechanical design and compensator design are also presented. 227 AN 3450311. AU Raimondi-T. TI JET experience with remote handling equipment and future prospects. SO 24 pp. Oct. 1988. YR 1988. RN JET-P(88)64. Issuing organization: JET Joint Undertaking, Abingdon, UK. AB The commissioning and testing of numerous pieces of equipment are in progress at JET. Two microprocessor controlled force feedback MASCOT IV servomanipulators have shown comparable characteristics to those of the previous analogue types. Teach and repeat software permits precision welding and repetitive operations in a robotics mode. Other computer aids are planned to improve the man-machine interface: tool-weight compensation, constraints along preferred lines or planes, automatic tracking of the TV cameras. The in-vessel transporter, provided with five vertical hinges, a pan-tilt-roll extension and special purpose end effectors, has been used under direct visual control to install 32 toroidal limiters and eight radiofrequency antennae. Tests of remote installation in teach and repeat were done, using the JET spare octant as a mock-up, achieving repeatability of better than 5 mm. A considerable number of special remote handling tools were used inside the vessel hands-on to align, cut and weld diagnostics ports and water pipes. The cutting and welding trolleys were used hands-on, on a total of 250 m of lip joints. The ex-vessel transporter, a crane-mounted vertical telescope, 17 m high with a 10 m horizontal arm, is being manufactured. It will be equipped with manipulator and TV systems and controlled via joystick or keyboard or in teach and repeat. Image processing for collision avoidance is being studied. A low level transporter was used for turbo-pump replacement and is now being equipped with remote control. Mock-up work has started on the replacement of the Neutral Injector sources. Bench tests on flanges, heating jackets and connectors are being done to identify refinements needed. The in-vessel inspection system has been used at high temperature in vacuum. 228 AN 3446289. AU Raimondi-T. IN JET Joint Undertaking, Abingdon, UK. TI The JET experience with remote handling equipment and future prospects. SO Fusion Engineering and Design. vol.11, no.1-2. pp. 197-208. June-July 1989. CT 15th Symposium on Fusion Technology. Utrecht, Netherlands. 19-23 Sept. 1988. YR 1989. RN CCCC: 0920-3796/89/$03.50. AB The commissioning and testing of numerous pieces of equipment are now in progress at JET. Two microprocessor controlled force feedback MASCOT IV servomanipulators have shown comparable characteristics to those of the previous analogue types. Teach and software permits precision welding and repetitive operations in a robotics mode. Other computer aids are planned to improve the man-machine interface: tool-weight compensation, constraints along preferred lines or planes, automatic tracking of the TV cameras. The in-vessel transporter, provided with 5 vertical hinges, a pan-tilt-roll extension and special purpose end effectors has been used under direct visual control to install 32 toroidal limiters and 8 radio frequency antennae. Tests of remote installation in teach and repeat were done, using the JET spare octant as a mock-up, achieving repeatability of better than 5 mm. A considerable number of special remote handling tools were used inside the vessel hands-on to align, cut and weld diagnostics ports and water pipes. The cutting and welding trolleys were used hands-on, on a total of 250 m of lip joints. The ex-vessel transporter, a crane-mounted vertical telescope, 17 m high with a 10 m horizontal arm, is being manufactured. It will be equipped with manipulator and TV systems and controlled via joystick or keyboard or in teach and repeat. Image processing for collision avoidance is being studied. A low level transporter was used for turbo-pump replacement and is now being equipped with remote control. Mock-up work has started on the replacement of the Neutral Injector sources. Bench tests on flanges, heating jackets and connectors are being done to identify refinements needed. The in-vessel inspection system has been used at high temperature in vacuum. 229 AN 3444058. AU Ozguner-U. Yurkovich-S. Al-Abbass-F. IN Dept. of Electr. Eng., Ohio State Univ., Columbus, OH, USA. TI Decentralized variable structure control of a two-arm robotic system. SO Journal of Robotic Systems. vol.4, no.3. pp. 377-95. June 1987. YR 1987. RN CCCC: 0741-2223/87/030377-19$04.00. AB The control problem for a two-arm robotic system in coordinated motion is addressed. A hierarchical framework, employing two levels of control hierarchy, it utilized, and the decentralized model reference adaptive control approach using variable structure controllers (DMRA-VSC) is applied. Within the control hierarchy, the DMRA-VSC strategy is accomplished at the lower level, where control is responsible for the servoing of each joint. These local controllers are coordinated by the high-level, central controller, whose task is to provide the local controllers with the upper bound on the dynamical interactions with other subsystems. The local controllers are responsible for making each link follow the prescribed local reference subsystem in moving from one position to another. This is done using the local measurements and the information provided by the central controller. Advantages of the DMRA-VSC approach for multiple manipulator control include the inherent robustness properties to nonlinearities and interaction effects, the decentralization structure facilitating ease in multiple manipulator system programming and implementation, and the general structure of the controller which allows further extensions such as force feedback. 230 AN 3402810. AU Massey-J-T. Hovey-G-W. Schneider-W. Chubbuck-J-G. Georgopoulos-A-P. IN Dept. of Neurosci., Johns Hopkins Univ., Baltimore, MD, USA. TI A method for studying the control of three-dimensional isometric forces using dynamic stereogram. SO Journal of Neuroscience Methods. vol.26, no.2. pp. 123-7. Dec. 1988. YR 1988. RN CCCC: 0165-0270/88/$03.50. AB A system has been developed for measuring the three-dimensional (3D) isometric forces produced by the arm in response to a visual stimulus. The output of 3 load cells is combined to determine the components of the 3D response force. The maximum force range of the load cells is 2000 g which can be read with a resolution of 4 g and with a measured accuracy of +/-10 g. An overload stop protects the device to a load of 23 kg. The visual instruction to the subject concerning the direction and magnitude of the 3D force vector to be produced is presented using a vivid spherical stereogram. This stereogram is produced using the anaglyphic technique where the left and right images are separated by color filters. A dense aggregation of points defines the target cursor, which can be positioned anywhere inside or on the surface of the sphere. This cursor can represent a stationary or a moving target. A force feedback cursor can be provided to indicate to the subject his/her response. The color display on the cathode ray tube is produced by a display generator driven by a computer. 231 AN 3389686. AU Lorenz-R-D. Meyer-K-M. Van-De-Riet-D-M. IN Wisconsin Univ., Madison, WI, USA. TI A novel, compliant, four degree-of-freedom, robotic fingertip sensor. SO Published by: IEEE. New York, NY, USA. 1988. CT Conference Record of the 1988 Industry Applications Society Annual Meeting (IEEE Cat. No.88CH2565-0). Pittsburgh, PA, USA. pp. 1414-19 vol.2. IEEE. 2-7 Oct. 1988. YR 1988. RN CCCC: CH2565-0/88/0000-1414$01.00. AB A novel, low-cost, compliant fingertip sensor for robotic gripper applications is presented. The sensor is intended for use in grippers where force feedback information is needed, such as in clean room or space applications where telerobotic operation is desired. The fingertip is approximately the size of a male, adult thumb and is approximately as compliant as human flesh. The sensor was designed to optimize the sensitivity to four components of force/torque; the normal force, both tangential force terms, and torque about the normal axis. Finite-element analysis was used to optimize the shape of the fingertip and the location/size of the PVDF piezoelectric sensing elements. The authors present the design analysis and experimental results from evaluation of prototype sensors. 232 AN 3383797. AU Hagner-D. Webster-J-G. IN Dept. of Electr. & Comput. Eng., Wisconsin Univ., Madison, WI, USA. TI Telepresence for touch and proprioception in teleoperator systems. SO IEEE Transactions on Systems, Man and Cybernetics. vol.18, no.6. pp. 1020-3. Nov.-Dec. 1988. YR 1988. RN CCCC: 0018-9472/88/1100-1020$01.00. AB The control and operation of mechanical manipulators by a human and the use of sensory tactile and force feedback is reviewed. The terms telepresence, teleproprioception, and teletouch are defined and relevant technologies that have or could have been applied to teleoperation are discussed. An ideal method of tactile sensory feedback for teleoperators that is based upon reproduction of the object's contour is discussed, and its practicality considered. Previously developed components that could be used to build a system incorporating sensory tactile and force feedback are presented. 233 AN 3347121. AU Gorinevskii-D-M. Shneider-A-Yu. TI Dynamics of small motions of a walking robot when there is feedback with respect to the support reactions. SO Izvestiya Akademii Nauk SSSR, Mekhanika Tverdogo Tela. vol.22, no.6. pp. 39-47. 1987. TR Mechanics of Solids. vol.22, no.6. pp. 37-46. 1987. YR 1987. 1987. RN CCCC: 0025-6544/87/$20.00. AB A six-legged walking robot is a statically indeterminate mechanical system. The problem of distributing the support reactions acting on the legs is one of the key problems in setting up the motions of such a robot. The criteria used as a basis for solving the distribution problem vary; they include the requirement that the support reactions belong to the cones of friction, that the power consumed by the drives be minimized, that the pressure of the legs on the ground be uniform, and so forth. Specified values of the support reactions can be maintained by using feedback with respect to readings of force sensors mounted in the legs. When there is position and force feedback, the leg responds to an external stimulus like an elastic spring with a compliance that is proportional to the force feedback coefficient. This behavior is called 'active compliance'. By realizing active compliance of the legs of a walking robot, it is possible to control the distribution of the support reactions upon motion over rigid and nonrigid ground. 234 AN 3343109. AU Stokic-D-M. Vukobratovic-M-K. IN Inst. 'Mihajlo Pupin', Beograd, Yugoslavia. TI Robust control of a multirobot system. SO Robotics and Computer-Integrated Manufacturing. vol.5, no.2-3. pp. 165-72. 1989. CT International Conference on Robotics. Dubrovnik, Yugoslavia. 24-27 Aug. 1987. YR 1989. RN CCCC: 0736-5845/89/$3.00+.00. AB The synthesis of control for a multirobot system is considered. The executive control level for a system consisting of several robots, which may come into contact with each other, is synthesized as a decentralized controller. The authors synthesized a local controller around each joint of each robot in the system. Then they analyzed whether the multirobot system is stable with such local controllers. Since the robots may come into contact with each other the structure of the interconnections between the subsystems may change during the operation of the system. Thus, one must consider the connective stability of the robotic system. To compensate for changes in the structure of the interconnections the authors introduced force feedback as a global control. 235 AN 3304802. AU Conrad-F. Jensen-C-J-D. Edited by: Isermann-R. IN Control Eng. Inst., Tech. Univ. of Denmark, Lyngby, Denmark. TI Design of hydraulic force control systems with state estimate feedback. SO Published by: Pergamon. Oxford, UK. 1988. CT Automatic Control - World Congress, 1987. Selected Papers from the 10th Triennial World Congress of the International Federation of Automatic Control. Munich, West Germany. pp. 307-12 vol.3. IFAC. IMACS. IFIP. et al. 27-31 July 1987. YR 1988. AB The control problem of keeping a desired force acting on a machine part can often be solved by using a servo controlled oil hydraulic actuator unit. The paper describes the results of an analytical and experimental investigation of some new design principles of force control systems which are based on the application of an electro-hydraulic servovalve controlling the volume rate flow to a hydraulic motor. It is shown how the system performance can be improved compared to a conventional force feedback by using the following control principles: a controller with output feedback and velocity feedforward: a Luenberger observer and state estimate feedback, a Luenberger observer, state estimate feedback, and unity output feedback; and velocity feedforward combined with the third principle given above. 236 AN 3301463. AU El-Maraghy-H-A. Payandeh-S. IN Centre for Flexible Manuf. Res. & Dev., McMaster Univ., Hamilton, Ont., Canada. TI Knowledge-based contact reasoning for compliant robot tasks. SO International Journal of Advanced Manufacturing Technology. vol.3, no.5. pp. 61-80. Nov. 1988. YR 1988. AB A method for interpreting the contact force feedback, during compliant robot motion control, using kinematic screws is presented. Domain specific rules combined with partial a priori knowledge of mating parts geometry and interpreted force signals are used to reason and make inferences about the initial contact configuration. The likely contact surfaces are predicted and point(s) of contact are fully defined. These surfaces are idealised and represented by quadratic equations or polyhedral surfaces. The geometric properties of surfaces at the contact location are used to select the contact configuration when multiple solutions exist. An algorithm for predicting the expected contact configuration (ECC) has been developed. 237 AN 3286803. AU Kreutz-K. Lokshin-A. IN Jet Propulsion Lab., California Inst. of Technol., Pasadena, CA, USA. TI Load balancing and closed chain multiple arm control. SO Published by: American Autom. Control Council. Green Valley, AZ, USA. 1988. CT Proceedings of the 1988 American Control Conference. Atlanta, GA, USA. pp. 2148-55 vol.3. American Autom. Control Council. 15-17 June 1988. YR 1988. AB The authors give the general dynamical equations for several rigid link manipulators rigidly grasping a commonly held rigid object. It is shown that the number of lost arm configuration degrees of freedom due to imposing the closed-loop kinematic constraints is the same as the number of degrees of freedom for controlling the internal forces of the closed-chain system. This number is equal to the dimension of the kernel of the Jacobian operator which transforms contact forces to the net forces acting on the held object, and it is shown that this kernel can be identified with the subspace of controllable internal forces of the closed-chain system. Control of these forces makes it possible to regulate the grasping forces imparted to the held object or to control the load taken by each arm. It is shown that the internal forces can be influenced without affecting the control of the configuration degrees of freedom. Control laws of the feedback linearization type are shown to be useful for controlling the location and attitude of a frame fixed with respect to the held object, while simultaneously controlling the internal forces of the closed-chain system. Force feedback can be used to linearize and control the system even when the held object has unknown mass properties. If saturation effects are ignored, an unconstrained quadratic optimization can be performed to distribute the load optimally among the joint actuators. 238 AN 3260411. AU Tello-E-R. TI Between man and machine (user interfaces). SO BYTE. vol.13, no.9. pp. 288-93. Sept. 1988. YR 1988. AB New advances in user-interface technology could change the way users interact with computers. The paper looks at some of these advantages: the DataGlove, DataSuit, force-feedback technology, eye tracking, voice-recognition systems, and combinations of these.