Stator analysis and design of a spherical piezoelectric motor

A spherical motor driven by piezoelectric actuators is developed. Each set of piezoelectric actuators are laid in a line around a spherical surface, which is designed to provide one degree-of-freedom motion. Applying appropriate voltage signal with phase difference on the neighboring actuators so that traveling wave is generated. All sets of a series of piezoelectric actuators are constructed mutually perpendicular. Curved piezoelectric actuator is designed in order to attach to the spherical surface. Stator design and analysis is presented in this article. Resonance frequency and vibration amplitude is estimated via ANSYS simulation. A sample of 2DOF is built to examine the performance of 1DOF and 2DOF by experiment. In comparison simulations with experimental results, they are in a good agreement. Performance evaluation of rotation speed and torque of the stator is also presented.