grbl is stepper motor controller ... for the normal drivers included on grbl Arduino shields (or integrated Arduino+drivers equivalents), and so I have been considering designing my own to link to ...

The solution is named Ethersweep, and is a small PCB stack that sits on the rear of the common NEMA17-format stepper motor ... with Arduino covering the firmware and host control side in python.

To get around this, [RoTechnic] moved the wrist stepper motors off the arms entirely. He built a push-pull mechanism that uses braided fishing line to transfer motion to the robot arm’s wrist ...