So we have run into this issue a few times, where one of our motors (its happened with both a Neo and a 550) seems like it doesn’t have enough torque to start spinning. After enabling and attempting to run it, even just from Rev Hardware Client, it requires a small manual bump by hand to then immediately runs up to speed.
We’ve tried everything - taking off chains that would cause friction, re-wiring, fiddling with maximum currents and ramp-up times, and all sorts of other things. We also sometimes get brownout sticky faults in hardware client, not sure if that has to do with this. Is there something we’re missing or is this a internal motor or sparkmax issue?
That sure sounds like a loose phase connection or a loose encoder cable connection. It could also be a problem with that particular Spark Max - maybe one of the phases in the H-bridge is open. Before you switch Spark Maxes though, check your motor winding to encoder resistance to be sure your NEO / NEO550 hasn’t failed short between encoder and phases, this will kill any Spark Max that attempts to run the motor.
I’ll take a look when I can get back to our robot. I’m now assuming that its a wiring issue - all our motors and sparkmaxes are brand-new for this year and haven’t been run much.