Thanks for your reply, Nikarus. I have looked at the Wii camera hack and it is a possibility along with Freetrack or TrackIR. Initially I was looking for something really simple and cheap. I have checked out such things as line following robots, robots that home on IR beacons and robotic tanks that aim at an IR target. I just need to get some bits and start playing.
Well the IR sensors and emitters I linked you are easy enough to hook up and start playing with. The thing I can see as a problem with your idea is it will be difficult to track what angle your head is relative to the screen. But I haven't given that kidn of system that exceptionally much thought (since the motors probably wouldn't be able to react to your head motions quite as fast as you'd want them to.
I am also thinking of light dependent resistors. You are supposed to be able to get ones that operate in the IR spectrum but I have not found one yet. Visible light ones might work though with a pencil beam and a shroud to keep out most of ambiant light.
Photoresistors could work to. These are best used for sensing the intensity of light though. I could see a lot of issues coming up with tryign to use them to track a particular light however.
I am busy researching and was hoping for some pointers given the application and distance involved. The Society of Robots site I found checking your link to Sparkfun is looking promising. Thanks again.
Given the distance your working, most any of the IR setups will work. Actually for airsoft I've tried putting IR strobes into the shoulders of a couple of my teammates and making it so that when I point my gun at them, the gun detects the strobe and will blink the red dot sight to show that its one of my friends I'm aiming at (within about 3 degrees accuracy too with the tube I setup to block out other angles). And when using an array of IR leds on each shoulder, I could get them to sense up to about 70ft away (far enough that through the trees I couldn't tell they were on my team) However that was a couple dozen LEDs For head to monitor, of about 3 ft range, you're definable gonna be fine for getting a good signal. Make sure to watch out for viewing angles on your detectors though.
Ps. A multi monitor setup still does not solve the issue of looking at a fixed point whilst the view moves behind but such a set up on a pan and tilt mechanism zooming around your head would be awesome.
Back to the zooming. Thinking fast It wouldnt be to expensive to hang your monitor from a rotating jig from the ceiling (with a counterweight). And with good bearings and a sufficiently powerful motor, It could probably respond fairly quick, Hope noone is standing nearby at the time. Now this mount would rotate the monitor around your head. and probably max out at going 90 degrees either way (since it would be hard to make the slip rings to do a 360 rotation). Pan and tilt motors wouldn't be too hard to manage cause they wouldnt need to be anywhere near the size. The lift and lower motor though I can see trouble.
Though I might just be blowing it out of proportion and you're just planning on panning and tilting the monitor so its always facing you, without it moving its base at all. Well thats easy then, the other ones hard but still doable.
If you could actually give a little more insight into what you're actually trying to build (quick drawing perhaps) I might be able to be a bit more helpful, cause I'm pretty sure what I'm envisioning is wrong. Best of luck to you though either way.
PS. which sims you play if any of them are online? Its a lot of trouble to get good matches going in a lot of games. And I'm always looking for a good fight.