A neural-network-based iterative controller of speed control for ultrasonic motors

A neural-network-based iterative controller is presented focusing on the speed control of ultrasonic motors. Suitable ranges of the adaptive learning rates are presented through the theoretical analysis on the proposed model, which could guarantee the fastest convergence of the neural network controller. Numerical results show that the neural-network-based controller is effective for various kinds of reference speeds of ultrasonic motors. Comparisons with the existing method show that the precision of control could be increased using the proposed method. Simulations also show that the proposed scheme is fairly robust against random disturbance to the control variables.