The kinematic analysis of three-degree of freedom cylindrical ultrasonic motors

Based on the basic vibration equation and finite element analysis of stator, this paper first gets the fundamental equation of vibration excited by three phase driving excitations with same frequency, different voltage amplitude, phases. Then three fundamental equation of vibration are combined into final equation of motion of three-DOF (degree of freedom) CUSM (cylindrical ultrasonic motors) with spherical rotor excited simultaneously by three phase driving excitations. The obtained expressions provide a theoretical understanding of the motor operation and driving mechanism and are very valuable to the control of locus and position, the optimized designing of cylinder stator