Extended state observer-based control with an adjustable parameter for a large ground-based telescope

作     者：Xiao-Xia Yang Yong-Ting Deng Bin Zhang Jian-Li Wang Xiao-Xia Yang;Yong-Ting Deng;Bin Zhang;Jian-Li Wang

作者机构：Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China 

出 版 物：《Research in Astronomy and Astrophysics》 (天文和天体物理学研究（英文版）)

年 卷 期：2021年第21卷第12期

页      面：509-518页

核心收录：

学科分类：07[理学] 070401[理学-天体物理] 0704[理学-天文学] 

基　　金：supported in part by the National Natural Science Foundation of China (Grant Nos. 12122304 and 11973041) in part by the Youth Innovation Promotion Association CAS (No. 2019218) 

主　　题：extended state observer large ground based telescope recursive least square disturbance rejection 

摘      要：The high-precision requirements will always be constrained due to the complicated operating conditions of the ground-based telescope. Owing to various internal and external disturbances, it is necessary to study a control method, which should have a good ability on disturbance rejection and a good adaptability on system parameter variation. The traditional proportional-integral(PI) controller has the advantage of simple and easy adjustment, but it cannot deal with the disturbances well in different situations. This paper proposes a simplified active disturbance rejection control law, whose debugging is as simple as the PI controller, and with better disturbance rejection ability and parameter adaptability. It adopts a simplified second-order extended state observer(ESO) with an adjustable parameter to accommodate the significant variation of the inertia during the different design stages of the telescope. The gain parameter of the ESO can be adjusted online with a recursive least square estimating method once the system parameter has changed significantly. Thus, the ESO can estimate the total disturbances timely and the controller will compensate them accordingly. With the adjustable parameter of the ESO, the controller can always achieve better performance in different applications of the telescope. The simulation and experimental verification of the control law was conducted on a 1.2-meter ground based telescope. The results verify the necessity of adjusting the parameter of the ESO, and demonstrate better disturbance rejection ability in a large range of speed variations during the design stages of the telescope.