Stepper Motors

A typical hybrid stepper has 200 steps per revolution (1.8° per step). Driving the coils in sequence moves the rotor step by step; microstepping drivers (A4988, DRV8825, TMC2209) divide each step into up to 256 microsteps for smoothness.

$\text{steps per mm} = \frac{\text{steps/rev} \times \text{microsteps}}{\text{mm per rev}}$

Pros: precise positioning without feedback, high holding torque. Cons: torque falls at high speed, and if overloaded they lose steps silently. Set the driver's current limit to the motor rating.