Miniature flat type inertial piezoelectric motor

Abstract

Study of a novel design miniature linear piezoelectric motor is proposed in the paper. Size of the motor not exceeds 150 mm3. Piezoelectric motor consists of “butterfly” type actuator and slider. Elliptical trajectory of the actuator is achieved using bending oscillations of the plates of actuator when harmonic or short impulse type excitation is used. Contact zone trajectory of motion is analyzed for both type of excitation. Advantages of impulse type excitation are simpler electric circuit scheme, lesser dependence between the rotor torque and excitation frequency. It allows increasing torque of the rotor without increasing dimensions and mass of the actuator. Numerical modeling of the piezoelectric motor was done to analyze natural frequencies, modal shapes of the actuator and to examine actuator response to the harmonic and impulse type excitation. Experimental prototype of the piezoelectric motor was built and measurement contact zone motion was done. Results of numerical and experimental studies are discussed.