Electodynamic Characteristics of Ultrasonic Spherical Motors

摘要

An ultrasonic spherical motor consisting of piezoelectric curvilinear drivers is designed and its electrodynamic characteristics are evaluated in this study. Fundamental design concept is discussed and its key component, i.e., a piezoelectric curvilinear arc driver, is evaluated. System equations, vibration behavior and wave propagation are investigated. Then, a conceptual model of piezoelectric circular arc driver with required electronics is built and tested to demonstrate the feasibility and performance of the spherical motor. Fabrication of the piezoelectric circular arc driver and implementation are respectively discussed, followed by simulations of the finite element (FE) model, and demonstration of the conceptual model. Experimental data of the conceptual curvilinear arc motor is compared with the finite element results. Operating frequency of the conceptual motor compares well with the finite element result. The conceptual model also demonstrates that the curvilinear arc motor performs as expected and is capable to achieve spherical motion.