Servo drives are a cornerstone of modern machinery, enabling precise control of motion in industrial and automated systems.

A servo uses a potentiometer attached to the output shaft in order to sense position, and the internal electronics take care of driving the motor to move the shaft to the desired angle.

[Frank Herrmann] had an interesting idea to turn a geared DC motor into a servo motor assembly, but with a stepper motor-like interface. By stacking some small PCBs behind the motor body ...