[purduephotog]

Has anyone achieved the perfect velocity sensor platform?

I've seen measurements done with mice (x/y), but that wouldn't help too much with rotation. I believe a set of 3 or 4 sensors (three would be easier) arranged in an equilateral triangle underneath would achieve that.

Encoders? Don't catch slippage.
Accelerometers? Can be affected by jerk and/or require precise timing and encoding (see rotation).
Gyros? Fix the rotation issue- assuming the lever arms are correctly accounted for.
Ultrasonic? Some great success on a whitepaper at 40mph with a modified set of transducers.
GPS? Heh.
Wifi signal?

Suggestions would be most welcome. I've been wanting to build a sensor for this for years.