A novel rotary piezoelectric motor for aerospace application

A novel in-plane mode rotary ultrasonic motor is designed in this paper. Four Langevin type bending vibrators are placed separately around the ring shaped stator and used to excite an in-plane vibration mode of the ring stator. Two tapered rotors are assembled to the inner ring of the stator and clamped together by screw nut. A thin cylindrical supporting is placed under the stator ring, which makes the motor more stable and convenient to fix. This ultrasonic motor has no bearings, which is good at operating in cryogenic and vacuum environment.