A NONCONTACT MEASUREMENT TECHNIQUE FOR PIEZOELECTRIC TRANSDUCERS

Amplitude and velocity of vibration and their spatial distribution are very important parameters for ultrasonic motors. A complete automatic measurement unit built around a laser vibrometer has been developed i n our laboratory. The main object of this non-contact measurement tech nique is to obtain experimental values of the particular displacement on the stator surface. Theoretical values can be obtained by modelling but the nonlinear effects are difficult to take into account in these complex structures. In this paper, we report on the measurement syste m and we show some results obtained with two types of motor.