A miniature cylindrical piezoelectric motor with an asymmetric vibrator.

In this paper, a miniature cylindrical-type traveling wave piezoelectric motor with an asymmetric vibrator is reported. The proposed piezoelectric motor uses only a single piezoelectric plate that is asymmetrically bonded on a cylindrical tube, but it still can excite two bidirectional traveling waves by changing the driving signal frequencies. Typical elliptic motions are observed by using the finite element method (FEM).

High resolution miniaturized stepper ultrasonic motor using differential composite motion.

Experiments show that there is a limited minimum stepped angle in ultrasonic motors (USM). The research on the minimum angle of stepper USM with 15 mm in diameter and wobbling mode is being carried out. This paper presents a novel way to decrease the minimum stepped angle of USM based on the principle of differential composite motion (DCM), i.