Nw. Hagood et Aj. Mcfarland, MODELING OF A PIEZOELECTRIC ROTARY ULTRASONIC MOTOR, IEEE transactions on ultrasonics, ferroelectrics, and frequency control, 42(2), 1995, pp. 210-224
A piezoelectric rotary ultrasonic motor is modeled for the purpose of
predicting, a priori, motor performance as a function of design parame
ters. The Rayleigh-Ritz assumed mode energy method is used to model th
e distributed piezoceramics and the traveling wave dynamics of the sta
tor. Natural frequencies and modeshapes are obtained for a generally c
onfigured motor. Nonlinear normal and tangential interface forces betw
een the rotor and stator are incorporated into the forcing function al
ong with the linear piezoelectric forcing. Given the applied torque, a
pplied axial Loading, and piezo drive voltages as inputs to the model,
general motor performance measures are obtained-namely speed, input p
ower, output power, and efficiency. The approach presented here provid
es a general framework for modeling these motors as well as a design t
ool for optimizing prototypes with the added flexibility of allowing f
or a wide variety of geometries and materials.