Improvement on the Structure Design of a Kind of Linear Piezoelectric Motor with Flexible Drive-Foot

Linear piezoelectric motors have wide application prospects in precision instrument, biomedical engineering and many other high technology fields. In this paper, a linear piezoelectric motor operating in non-resonant state was proposed by using a flexible mechanism with characteristics of precision displacement output. Since the stator structural characteristic affects the stability and output performance of the motor directly, this paper focused on the improvement on the structure design of a motor stator with flexible five-bar drive-foot. Firstly, by analyzing the displacement output characteristics of flexible five-bar mechanism, the elliptical trajectory of drive-tip was investigated. Then the drive-foot was particularly designed with the characteristics of flexible structure, and its main structure parameters ware improved by the finite element method. Further, the integrated structure of stator was designed and fabricated. Finally, the comparison tests of the two motors were carried out. The experimental results show that the output force and efficiency of the improved piezoelectric motor are increased by 52.38% and 159.15%, respectively.