Design and primitive study of a cylindrical traveling wave ultrasonic motor using outer excitation

A cylindrical traveling wave ultrasonic motor using outer excitation of two bending transducers is proposed in this paper. To avoid the drawbacks of conventional traveling wave ultrasonic motors, sandwich structure of PZT elements and d₃₃ mode of PZT are used here. Working principle and design analysis by means of FEM method are detailed. A prototype motor has been fabricated and tested. Although the tested results of output torque was not ideal as compared with desired, the original configuration idea has great potential to obtain strong out put in our further study on it.