Eigenfrequency identification for optimization on multicomponent ultrasonic actuators

Abstract

The design of ultrasonic motors can be divided into following steps: dynamic studies and application of finite element method (FEM) of piezoelectric actuators, optimization of the actuator and development of a control scheme. This paper presents a study of optimization of the electrodes dislocation of ultrasonic actuators. The goals of the optimization problem are to unify excitation voltage forms, to achieve reverse motion and maximum coefficient of efficiency. Fulfilling this requirement means that a source of current has to generate voltage of constant frequency, amplitude and phase; reverse motion must be achieved only by changing the polarity of a source of current, and that the surface of the ultrasonic actuator is fully covered with electrodes. Also, an algorithm of modal shape identification is presented in this paper.