well, michael designed us a multi motor drive train, and it's still kicking (well, if the robot was put back together). maybe i can get a pic of it later today. i know that we had a small gear on the chiphua motor shaft, and then a really big one on the drill motor. they don't spin at exactly the same speed, but it's made so that the chiphua will just use it's power to time it correctly. then, we used the drill motor transmission, set to high (i think), and used the shaft on that to drive wheels/treads. i know that's not an extremely detailed explination, but i'm a programmer
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