Design and Experiments of a Piezoelectric Motor Using Three Rotating Mode Actuators

This paper represents a numerical and experimental investigation of the multicell piezoelectric motor. The proposed design consists of three individual cells that are integrated into the stator, double rotor, and a preload system combined into a symmetrical structure of the motor. Each of the cells is characterized by a traveling wave and rotating mode motor. A finite element numerical analysis is carried out to obtain optimal geometrical dimensions of the individual cell in terms of generated vibrations and resonant frequencies of the structure. The results of the numerical analysis are compared with analytical calculations based on the equivalent circuit theory. Experimental tests are also presented, including laser interferometry measurements of vibrations generated at the surface of the stator, impedance analysis, as well as measurements of mechanical characteristics of the complete motor. The final stage of the study concludes that the presented motor can provide relatively high torque compared with other traveling wave rotary motors.