Characterization of an Asymmetric Disk-Type Ultrasonic Motor With Single-Phase Current Drive

This paper presents experimental measurement techniques for the characteristics and performance of an asymmetric disk-type ultrasonic motor with single-phase current drive. A single-phase driving circuitry with a constant-current output is proposed to provide a steady driving current for the motor´s stator to maintain the driving frequencies at resonant and antiresonant frequencies of the stator. Experimental results obtained from the laser vibrometer, dynamic analyzer, and photodetector are employed to investigate and discuss the characteristics and speed servoing performance of the motor with its proposed driver and a simple proportional-integral (PI) speed controller via a digital signal processor (DSP).