Cause of Vibration in Stepper Motors

When a stepper motor makes a move from one step to the next, the rotor doesn't immediately stop. the rotor actually passes the final position, is drawn back, passes the final in the opposite direction and continues to move back and forth until it finally comes to a rest. We call this "ringing" and it occurs every single step the motor takes. Similar to a bungee cord, the momentum carries the rotor past its stop point, it then "bounces" back and forth until finally coming to rest. In most cases, however, the motor is commanded to move to the next step before it comes to a rest.