A novel 3-DOF ultrasonic motor with two cylinder stators clamped

In this paper, authors present a novel 3-DOF ultrasonic motor with two cylinder stators clamped. Two cylinder stators are used to grip the sphere rotor, and clamp force is applied to the stators instead of rotor. With this novel method, the pre-pressure of 3-DOF cylinder ultrasonic motor between the stators and the rotor is enlarged, and the output moment is also increased largely. The two stators are applied by cross excitation alternating voltage respectively, and the driving forces of the stators are in the same direction. So the pre-pressure is enlarged, and output moment is enlarged too.