Nonholonomic nonlinear oscillator model for a bar-type piezoelectric motor

Over the past years, piezoelectric ultrasonic motors have received considerable attention. Significant research has been done towards modeling disc and shell type ultrasonic traveling wave motors. In this paper, a simple mathematical model of a different kind of ultrasonic motor, the bar-type or wobbling-disc motor is attempted, giving reliable results in the torque-speed characteristics including stick as well as slip conditions.