optical mouse motion sensor thread

[Nibbles]

Originally Posted by Don Rotolo

In a definitely unscientific experiment I wiggled my mouse about 6 inches at a rate of 'there-and-back' four times a second - about 4 FPS - and it seemed to track OK. Maybe it only tracked the ends (where I was moving slower as direction reversed). The link groves provided implied that it could be used - with modification - at fairly high (for a robot) speeds.

A better job then the mice I have access to (nothing fancy). My criteria was to have some tracking accuracy rate, report roughly the same velocity that is actually occurring , say, 99.9% of the time at max speed (20f/s). Anything less would mean that every few seconds it will report traveling in the wrong direction, enough to be problematic.

Looking at some of the more advanced mice (that I could find numbers for... seems like only marketing buzzwords like "LASER" and "OPTICAL" matter) can go up to 45in/s. Likely, since the playing surface grains (variance in contrast the mouse can lock onto) are larger then that on a mouse pad, you can pull back the mouse and shrink the size 4-6 times, so you could get up to 18 feet a second (or 35ft/s absolute best case if the tech specs are to be believed). But, you would have to find a USB to serial converter, and that mouse doesn't support PS/2 output (mice that do ship with a USB to PS/2 converter support the connection natively, the converter doesn't do any actual conversion of data). Take a really cheap computer with USB2.0 and serial, do some (quite a bit) of programming, and feed the results into the cRIO. And of course this is only theoretical, I haven't actually done any testing.