A ring-type traveling wave ultrasonic motor using optimized design of piezoelectric ceramics

This paper presents and verifies an idea for enhancing the vibration amplitude of a stator. In the optimized structure, two polarization areas are added to make full use of a piezoelectric ceramic. Vibration expressions of the stator are then derived to validate the feasibility of the design. Furthermore, a hollow ring-type ultrasonic motor (USM) is designed to coordinate the piezoelectric ceramic and structure of the motor is optimized by Finite Element Method (FEM) analysis. The resonant frequency is calculated by modal analysis and harmonic response analysis indicates that vibration amplitude of the stator has increased by 14.2%. Finally, a prototype is fabricated and simulation results are verified by experiment.