Minimising heat dissipation in ultrasonic piezomotors by working in a resonant mode

Heat dissipation in ultrasonic motors should be limited, especially in precision applications since it causes thermal deformations. Therefore, n easy-to-understand mechanical model was developed to simulate heat dissipation in an ultrasonic motor. This model involves the dielectric, iezoelectric and mechanical hysteretic losses of the piezoelectric material. Both the model and the experiments lead to the same recommendations o minimise the heat dissipation for ultrasonic motors. Large piezoactuators, exciting passive structures at high resonance frequencies result in a inimum heat dissipation. Furthermore, it was shown that the optimal frequency regarding minimal heat dissipation lies between the resonance nd the antiresonance frequency of the system, close to the resonance frequency. 2007 Elsevier Inc. All rights reserved.