4. Study of the reliability optimization of an ultrasonic motor

4.1 Presentation of the problem

Ring-shaped traveling-wave ultrasonic motors have many qualities, the most interesting of which are their simple architecture, high torque delivered at low rotational speed, high holding torque and insensitivity to stray magnetic fields. These features make them ideal for use in precision micromechanics, and open up a wide range of industrial applications. However, while these motors are used every day in complex mechatronic systems, the characterization of the actual mechanical behavior of each component is still imperfect. This example focuses on the SHINSEI USR 60 piezoelectric motor. The need to increase the service life of this motor, which is limited by high wear on its components, calls for in-depth analysis of the structure under operating conditions....