Performance analysis and optimization of the travelling wave ultrasonic motor

The authors present a method allowing evaluation of the mechanical performances (torque, speed, mechanical power, dissipated losses on the surface of contact between stator and rotor) of travelling wave ultrasonic motors. The visualization of the motor characteristics makes it possible for the manufacturer to optimize the operation point of the motor compared to the commonly used criteria. The method was developed based only on a 2-D equivalent mechanical model of the motor.