Experimental Study of a Radial Composite Ultrasonic Motor

A radial composite ultrasonic motor is studied with experimental method in this paper. Firstly, the impedance-frequency characteristics of the stator under free condition and assembled condition are measured with impedance analyzer in order to investigate the impact of the preload force between the stator and rotor on the resonant frequency of the stator. Subsequently, the vibration mechanism of the stator is studied with laser Doppler vibrometer. The radial vibration amplitude of the stator under different voltages are measured and analyzed. Finally, Torque-speed curves of the ultrasonic motor under different voltages are measured and compared. The feasibility of the motor is verified by experimental results. The study in this paper provides a reference value for designing and optimizing the radial composite ultrasonic motor.