Using Kevin's PWM outputs for a quieter drive system.

[Kevin Sevcik]

Phil,

The PWM outputs on the robot we're so fond of don't actually spit out a true PWM signal that you would directly use for controlling a motor. They spit out a pulse train of 1ms to 2ms pulses. The Victors interpret this as 100% reverse to 100% forward and PWM their outputs accordingly at their own PWM frequency. So in answer to your question, you can't make your motors quieter by sending the pulses faster, you can only update their speed faster than the standard 38Hz.

You could however call Kevin's PWM function faster to gain slightly better control over your steering or any other feedback controlled system. Most systems on our robots have bandwidths less than 38Hz, so the gain isn't going to be huge, but you should see an improvement. You should keep in mind however that you can only update the victors at around 120Hz max, so be certain you don't call the function any faster than that.