Abstract—When the ultrasonic motor is used to drive a stabilized platform, there will be variable load are applied on the motor. So the motor’s motion state is changed. It is necessary to carry out some relative researches on the problem. Firstly, this paper establishes the dynamics model of stabilized platform driven by the ultrasonic motor. Secondly, combined with the established model, the internal model controller is designed to satisfy the stability requirement of the stabilized platform from the disturbance to the output. In order to verify the control effect of the proposed controller, the control effect of the proposed controller is simulated and compared with the Proportion-Integral-Derivative controller. We can find that this control method is better than classical Proportion-Integral-Derivative controller. The unit step response time reduces 0.03s. The tracking error of 1Hz sinusoidal reference signal reduces from 1.9% to 0.6%. The ability of restraining the external disturbance improves about 10dB and the suppression band at about -30dB also increased by about 4Hz.

Index Terms—Ultrasonic motor, stabilized platform, sensitivity function, digital control.

Pan Song, Xu Zhang-Fan are with State Key Laboratory of Mechanics and Control of Mechanical Structures, Nanjing University of Aeronautics and Astronautics, 210016 Nanjing, China (email: pansong@nuaa.edu.cn).
Huang Wei-Qing is with School of Mechanical and Electrics Engineering, Guangzhou University, 510006 Guangzhou, China.

Cite: Pan Song, Xu Zhang-Fan, Huang Wei-Qing, "Digital Internal Module Controller Shaped by Sensitivity Function of Platform Driven by Ultrasonic Motor," International Journal of Applied Physics and Mathematics vol. 8, no. 3, pp. 45-52, 2018.