Fuzzy sliding-mode control for thin-disc ultrasonic motor

An approach of controller design based on fuzzy set and sliding-mode control scheme for positioning of a thin-disc ultrasonic motor is developed. A commercial available thin-disc buzzer as an actuating component of ultrasonic motor with simply structure has been demonstrated the benefit of cost and design in mechanism. The driving mechanism with hysteresis was studied. Through system identification, the approximated transfer function was obtained for fuzzy sliding-mode controller. It has been successfully applied to position tracking to prove the excellent robust performance in noise rejection.