The wheels are 8" stock trick wheels with the epdm (?) rollers. I don't know if we are going to keep them though, because they compress and we don't want to damage the floor. The acetals roll amazingly but don't have enough friction to make it up the ramp, so that's kind of up in the air as to what were going to do. The gearboxes are from Dewalt XRP Drills, interfaced to small CIM motors. We followed the whitepaper precisely, which can be found here.
http://www.chiefdelphi.com/forums/pa...le&paperid=398
We have a 9-tooth sprocket on the gearboxes and an 18 tooth sprocket on the wheel, though we may end up increasing the size of the sprocket on the wheel. Hope that answers any questions.