[cgmv123]

Originally Posted by Dr. Poptart

Thanks, I was thinking of doing this from the start but I just got around to it. That solved our movement problem, but now we've got another two problems on our hands. The first one we can fix - when we move forward, one side moves forward while the other moves backwards. This behavior persists through all movements as expected. We can solve that.

This is actually an expected behavior on most drive trains. You need to reverse one side in code. Like you said it's a very easy fix.

But we're also getting some issues with just driving. The left set of wheels will only move at very low speeds and behavior is unpredictable; sometimes it behaves as explained, and sometimes it just won't move at all. The right side can handle a bit more speed, but when I push our control joystick all the way forward the wheels stop and there is a stripping sort of sound in the gearbox. An outside mentor has suggested that perhaps one or more of the gearbox motors' keys may have slipped off. We're looking into the issue now. Does anyone else have any other ideas?

Make sure both motors in each gearbox are being powered. The easiest way to do this it to check the temperature of both motors after a long period of driving.