Quote:
|
Originally Posted by Kevin Sevcik
Ok, so the motors spinning at different speeds is utterly unrelated to programming, and almost definitely has nothing to do with the Victor calibration. The real issue is that all the motors FIRST gives us are wound with a lead angle of some amount. What it boils down to is that they have a preferred direction of rototation. So a given motor will run faster clockwise than counterclockwise. See this for ideas to compensate:
Robot Drifting |
Pages 8 and 9 of the FIRST Guidelines, tips, & good practices cover Motor Bias. There it states that there is no inherant bias in the windings of the CIM motor.
There will always be a few % difference between different motors. There can be a few more % in the gearbox and more from the chain tension. Weight distribution can cause the robot to be biased to one side as well. Poor wire connections can cause it as well. You should check all these. Even in the best case, it won't go perfectly straight (although the longer the wheelbase, the straighter). You can play with all of the above things to try and make it better, though.