A resonant inertial impact rotary piezoelectric motor based on a self-clamping structure

Rev Sci Instrum. 2023 Apr 1;94(4):045003. doi: 10.1063/5.0133681.

Abstract

A resonant inertial impact rotary piezoelectric motor based on a self-clamping structure is designed, assembled, and tested. The designed piezoelectric motor mainly includes a rotor (two vibrators, preload mechanism, and intermediate connection mechanism), a clamping mechanism, and another auxiliary mechanism. The piezoelectric ceramic sheet on the rotor drives the vibrator to swing under the excitation of a single harmonic wave. Because there is a clamping mechanism formed by the combination of clamp baffle and fixed clamp ring, thus the half-cycle resonant rotation of the rotor can be effectively completed, and repeated harmonic excitation can realize the unidirectional continuous rotation and swing of the rotor. The whole excitation process of the motor is in a resonance state, which has significant advantages, such as low friction and simple structure, compared with the traditional quasi-static piezoelectric motor. The structure of the piezoelectric motor is designed and analyzed using COMSOL5.5 software and then the motor performance is tested and analyzed by building an experimental platform to verify the feasibility of the motor design. The final experimental results show that the optimal working frequency of the piezoelectric motor is 150 Hz, which is consistent with the characteristic frequency of the simulation. When the motor prototype is under the conditions of optimal operating frequency 150 Hz, voltage 240 Vp-p, and preload torque 7.8 N.mm, the maximum angular speed can reach 2.4 rad/s, the maximum load can reach 27.8 N mm and the maximum resolution of the movement angle can reach 0.941°.