Drivetrain Stalling

Hey all,

Our team has a high-speed 4 motors 6 wheel tank drive that is directly connected to the motor. The drivetrain was fine at the start of the drive, but after quickly going back and forward, it will stall for 5 or 6 seconds. So our team concerned what’s the problem, is it the robot holds too much of weight? Or might just be some others issues? Our team’s solution right now is to change the high-speed motors to high torque motors, but I am still afraid it will stall after replacement. Anyone else faced the same issue?

Are you using a power expander? If so, how is it wired?

You are tripping a circuit breaker somewhere. Judging from your stated situation, it sounds like you are tripping the PTCs (heat activated circuit protection) on the motors. This is caused by putting too much strain on the motors. There maybe several reasons that this is happening. One, rapid changes in direction will cause the motors to overheat and trip the PTCs. Two, the robot might be too heavy for the load you are placing on it. You can change that several ways. In order to not lose speed, you would need to lighten your robot. That might not be an acceptable option, you might need everything you have on the robot.
Or you could switch to high torque, that should help. They will not stall as easily and might be a little slower.
If you are not tripping the motor PTCs, then you are tripping the circuit protection in the Cortex. Make sure that you distribute the load on the ports on the Cortex. There is a circuit breaker on motor ports 1-5 and another on ports 6-10. Otherwise, it is also a good idea to use a power expander.

Yes, we used two power expander for our 6 motors arm.

Thank you so much!