Investigation of omnidirectional piezoelectric actuator

Abstract

A study of a novel design composite piezoelectric actuator for omnidirectional object positioning is given in the paper. The actuator consists of a vibrating disc with a small cylinder mounted at the centre and a piezoceramic disc. The cylinder magnifies resonant bending vibrations of the vibrating disc and transmits driving force to the slider. Electrodes of the piezoceramic disc cover all the surface of the bottom and are divided into four equal sectors. 2D motion and rotation of the slider is achieved depending on the excitation scheme of the electrodes. Numerical modeling based on the finite element method was performed to obtain resonance frequencies and modal shapes of the actuator and to calculate the trajectories of contact point's movements under different excitation schemes of the electrodes. A prototype actuator was made and experimental outcomes of the oscillations of the working surfaces are given. Results of the numerical and experimental investigations are analyzed and discussed.