Experimental investigation of a mathematical model for traveling wave ultrasonic motors

Ultrasonic motors have many excellent performance features such as high-holding torque, high driving torque at low speed, silent operation, compactness, and no electromagnetic interferences. Due to such characteristics these motors have a potential for many applications such as automation, and robotics. The performance estimation of the ultrasonic motor is a function of operating conditions such as stiffness, number of piezoelectric segments, motor diameter, etc. Such performance is modeled using the accurate parameters of the motor. In this paper, the derivation of a mathematical model for traveling wave ultrasonic motors and its experimental validation is presented. The different components of the motor have been modeled individually. The resulting submodels are then assembled together to give the model of the complete motor. In order to validate the model, it is simulated with properly parameters and compared with experimental results obtained from an actual traveling wave ultrasonic motor "Shinsei USR60". Good agreement is obtained between simulated and experimental results.