“…A piezoelectric motor has the advantages of a simple structure, convenient control, easy miniaturization, a high displacement resolution, a fast response speed, and miniature precision actuation, which has been widely studied by many researchers [ 1 , 2 ]. According to the working principle, piezoelectric motors can be roughly divided into four types [ 3 , 4 , 5 , 6 , 7 , 8 ], including standing wave, travelling wave, inchworm, and impact motors. The standing wave and travelling wave motors are collectively called an ultrasonic motor.…”