Fix motor drivers from over-currenting themselves.

[infinityspike]

Description

During the 2025 Makerfaire, @rtyocum and @infinityspike were testing Bluey's motors and the hardware started smelling smokey. The robot was immediately e-stopped, and not used for the rest of the day.

Later, an exhaustive experiment was done using a power supply and ammeter to measure the current draw at the rated voltage of the motors (12V) under normal load. Normal load being:
Axis 1 (Base): no external force
Axis 2: (Shoulder): Resisting the force of gravity.
Axis 3 (Elbow): resisting the force of gravity.
Axis 4&5 (Wrist): no external force.
Axis 6 (Gripper): Not tested.
Axis 7/External Axis (Slide Base): no external force.

The experiment concluded that no conditions exhibited current draw that would over-current the motor drivers. A possibility is that the instantaneous start and stop current (which are difficult to read) may have gone over the peak current of the driver (3.2 Amps) due to back EMF.

Difficulty: [Medium]

Expected Completion Date: [2026-01-20]

Related Issues

[infinityspike]

1. Swap Motor Hats so that the other motors can be run by the team
2. Develop an bEMF protection circuit on KiCAD
3. Implement onto physical robot