Development of a two-degree-of-freedom piezoelectric motor using single plate vibrator

A two-degree-of-freedom piezoelectric motor using only one piezoelectric ceramic was proposed based on two vibration modes (B32 and B23) of a rectangular plate piezoelectric vibrator. The working principle was elaborated. Analytical and numerical models were established in order to design the piezoelectric vibrator. Calculations with finite element method were carried out using ANSYS software to validate the analytical models and demonstrate the elliptical trajectory of the four contact points between the stator and the sphere. Experimental result on the prototype shows that the numerical result including resonance frequency and elliptical motion of the motor indicate good agreement with the experimental one. The rotation speed around an axial along the direction of length of the rectangular piezoelectric vibrator of the motor is 37.7 r/min under the drive voltage 90 V and excitation frequency 44 kHz.