Improved Mathematical Model of a Traveling Wave Ultrasonic Motor (pp. 121-144)
Authors: (S. Belkhiat, Z. Boumous, F.Z. Kebbab, Laboratoire DAC HR UniversitÚ SÚtif I, Algeria)
Abstract: The traveling wave ultrasonic motor has excellent characteristics. It has advanced
features such as high-holding torque without supply high torque at low speed, absence of
parasitic magnetic fields, continuous contact, high response, quiet operation and small
size. All these properties make of this motor an ideal actuator, comparatively with the
electromagnetic one. During the last decade, many prototypes of ultrasonic motor have
been designed as a function needs. The advanced features are due to the working
principle that is based on high-frequency vibrations and due to the tribological
phenomenon acting in the zone of contact between stator and rotor. There is not a perfect
contact model that can control the contact dynamic between the rotor and the stator
because of it has a nonlinear behavior. For this reason, almost all research carried out is
based on a requirement that leads to some errors between the experimental and
theoretical results. Modeling of traveling wave ultrasonic motors (TWUM), has been, so,
subject much research.
In this chapter, optimal deformation angle and resonance frequency of frictional
material are investigated. Force expressions in the stator/rotor interface are developed.
Mechanical characteristics taking into account the effect of shearing deformation are
deduced and presented. Results of the simulation are validated using the measurements
made by other researchers on traveling wave piezoelectric motor AWM90-X, Daimler-
Benz type, and a prototype USM (AWM-90).