[NoSkaOnTheRadio]

hey all,

Team 1757 is running the shoulder joint of our arm with a pair of Keyang motors and an ANSI 25 chain, geared down by a 1:6 ratio. We're generating enough torque no problemo, but we just bent the axel that our drive sprocket is sitting on. We'd had problems with set screws before and managed to compe with those, but we're stumped now. The bent shaft is definitely a result of the motors; our hypothesis is that the motors have a bias in one direction (they're facing each other), and that they are twisting our shaft, thuereby weakening it and rendering it pretty vulnerable to bendage.

Has anyone observed bias in the Keyang motors? If so, has anyone quantified it so that we can compensate for it in our code? We have limited access to the machine shop at a neighboring school, and the lead time on these shafts is a few days. We would really love to stop beating them up.

Any help would be greatly appreciated, and repaid in full with a life debt. Well, maybe not a life debt, but lots of gratitude.

J*Dogg