From: Robin Hollands Subject: Re: TECH: A 'how-to' for cheap headtracking Date: 27 Sep 1995 11:00:15 GMT Organization: University of Sheffield , UK From: Robin Hollands Daniel Delgado wrote: >I call this the world's cheapest head tracker.... at about 6 dollars >for the mouse (the price here in Silicon Valley for a cheap serial >mouse) and about 5 dollars for the foam core. > > info about device... What an intriging device! If you're feeling a bit braver, you might try opening your mouse and having a look at the two slotted wheels that turn between the opto-transmitter and receiver. In most mice, you can unsolder these and put them and the slotted wheel in a remote system, with long(ish) wires running back to mouse. You can then set up a simple boom (just for ease of positioning) using, say, a large standard lamp, or make your own. At the end of the 'boom' you simply have two perpendicular linkages: BOOM l l ----- Yaw wheel l l i _________i 1 i Pitch Wheel 1 i 1 1 HEAD Using them direct like this gives a fairly coarse resolution, although with little ingenuity, you can displace the slotted wheel and make the Yaw and Pitch wheels comparitevely large and turning the the comparitevly small stem of the slotted wheels (i.e. gears) giving greater resolution, e.g. ooooo o o oo o o oo o o ooooo Yaw wheel Slotted Wheel I hadn't thought of this in time to get it in the book, and I haven't got time now to write it up fully, so please don't ask for any extra info. Just get in the workshop/garage/bedroom and play with the idea yourself - that's what homebrew/garage VR is all about :-) Cheers, Robin (r.hollands@sheffield.ac.uk)