[Alan Anderson]

I have two immediate thoughts.

First, did you do your drive practice on carpet? Robot handling is very dependent on the surface it's on. Many teams find that a robot which turns okay on tile or concrete won't turn at all on carpet.

Second, the general description you give, with separate systems seeming to be affected, points to a common problem. How does your battery wiring look? It sounds like you have a poor connection somewhere in the high current path. Double-check all the contact points: the main breaker, the distribution block, the breaker panels, etc. Feel for hot spots. Look at your battery voltage while you are running the motors.