Fuzzy modeling and position control of a traveling wave ultrasonic motor

The nonlinearities of ultrasonic motors (USMs) vary with driving condition and load-dependent characteristics such as the dead zone. Therefore, modeling and control of USMs are a difficult and challenging task. In this paper, the identification of the rotary traveling-wave type ultrasonic motor (RTWUSM) with dead-zone by means of Fuzzy Hammerstein model is proposed. The obtained model is used in model based predictive control. Simulation results not only show the good matching between the developed model and experimental measurements, but also indicate that the proposed modeling approach is useful for position control and disturbance rejection.