Proc. SPIE. 9677, AOPC 2015: Optical Test, Measurement, and Equipment
KEYWORDS: Control systems, Control systems design, Error analysis, Signal processing, Performance modeling, Servomechanisms, Detection and tracking algorithms, Systems modeling, Optical testing, Computer programming
According to the larger error when reversing in photoelectric tracking control system, the improved cascade Active Disturbance Rejection Controller (ADRC) is put forward to improve the system position tracking performance and tracking precision. First of all, this essay analyses the controlled object model and system control strategy; Then, it gives design method of the improved cascade ADRC; Finally, in order to analyses the improved cascade’s better control performance, in the condition of the same input signal ,the improved cascade ADRC, conventional ADRC-ADRC and traditional PI-PI controller are used in photoelectric tracking control system to do comparative experiment. The experiment results show that the improved cascade ADRC's performance is better than other two algorithms, the tracking error and the steady state mean square error are significantly reduced, tracking accuracy is significantly improved. The improved cascade ADRC is an appealing solution in dealing with industrial control system problems where uncertainties and interference abound.
In this paper, an improved Active Disturbance Rejection control (ADRC) method is proposed to enhance the tracking precision of telescope if the telescope runs in a low velocity. Low velocity telescope system usually suffers some obvious nonlinear disturbances, such as nonlinear friction and unknown external disturbance. Thereby, to ensure the tracking precision, multiple loops control structure is a common control method in telescope system, which includes current loop, velocity loop and position loop. The proposed control method is used in the velocity loop which consists of a PD controller and an Extend State Observer (ESO). The ESO is designed to estimate the disturbance involved in the telescope system. Besides, the PD controller is designed to stabilize the closed-loop system. Furthermore, this control method theoretically guarantees a prescribed tracking performance and final tracking accuracy. Finally, the experiment results show that the proposed control method has excellent performance for reducing the tracking error of low velocity.