Derivation and validation of a mathematical model for traveling wave ultrasonic motors

The derivation of a mathematical model for traveling wave ultrasonic motors and its experimental validation are reported. In a first step, the motor was structured into subsystems and models for the individual components were derived, simplified and described mathematically. The resulting submodels were then joined into an overall unified model of the motor, which allows us to study the impact of diverse motor parameters and control variables on the motor performance. In order to validate the model, systematic simulations with properly selected parameters were performed and compared with measurement results obtained from an actual traveling wave ultrasonic motor. Very good correspondence between model predictions and real motor behavior was observed. The validated model can be used in the design of traveling wave ultrasonic motors to optimize the performance by choosing the 'right' motor and control parameters at an early design stage.