基于扰动观测器的倾斜镜滑模控制  

Sliding Mode Control of Tip-tilt Mirror Based on Disturbance Observer

作　　者：赵德春 宋延嵩[2,3] 刘洋[2,3] 董岩[1,2] 张柏硕 ZHAO Dechun;SONG Yansong;LIU Yang;DONG Yan;ZHANG Baishuo(School of Electronic Information Engineering,Changchun University of Science and Tecnology,Changchun 130022,China;Fundamental Science on Space-Ground Laser Communication Technology Laboratory,Changchun University of Scienceand Technology,Changchun 130022,China;School of Optoelectronic Engineering,Changchun University of Science and Technology,Changchun 130022,China)

机构地区：[1]长春理工大学电子信息工程学院,长春130022 [2]长春理工大学空地激光通信国防重点学科实验室,长春130022 [3]长春理工大学光电工程学院,长春130022

出　　处：《光子学报》2022年第6期296-306,共11页Acta Photonica Sinica

基　　金：吉林省科技厅自然科学基金(No.YDZJ202101ZYTS193)。

摘　　要：为解决在外部扰动情况下自适应光学中倾斜镜的控制问题,提出了一种基于扰动观测器的滑模控制方法来抑制结构振动。在倾斜镜控制系统中,将新的扰动观测器加入到传统滑模控制方法中,设计新的滑模控制率来抑制抖振。改进后的扰动观测器不受精确模型的限制,仿真结果证明了该方法能够比较准确的跟踪系统状态,抑制扰动效果明显,降低了系统误差,输出曲线更接近给定的输入信号。实验结果表明,所设计的方法与传统滑模控制方法相比,方位轴控制误差由1.637μrad降低到1.083μrad,精度提高约51.2%,俯仰轴控制误差由1.966μrad降低到1.614μrad,精度提高约21.8%。该方法可大幅削弱由滑模控制方法造成的抖振及外部扰动,提高倾斜镜控制系统的稳定性。Tip-tilt mirror is a type of precision optical equipment that controls the direction of beam propagation in modern photoelectric systems.It has been utilized in space laser communications,adaptive optics,vehicle/airborne laser systems,image stabilization,astronomical telescopes,confocal microscopy,real-time laser scanning,capture target tracking,and other applications.The tip-tilt mirror is used in adaptive optics to correct the phase wavefront caused by atmospheric turbulence,which accounts for approximately 87%of the overall tilt.As a result,the tip-tilt mirror helps to rectify the first-order tilt of the system.The closed-loop performance of the adaptive optics system is severely harmed because the tip-tilt mirror is susceptible to wind vibration,equipment vibration,and platform vibration.As a result,the vibration must be minimized to approach the diffraction limit of optics.The standard closed-loop feedback control is ineffective in suppressing the vibration of the tip-tilt mirror,reducing closed-loop performance.In consequence,research into novel anti-vibration technology is critical to improving the closed-loop performance of the tip-tilt mirror.There are numerous methods for reducing vibration in use today.For example,literature offered a disturbance-based feedforward control method to suppress structural vibration of the tip-tilt mirror system,which involved measuring the disturbance with an accelerometer or a gyroscope and then feeding the disturbance with signal reconstruction.Returning to the system,the controller is not limited by low-rate sampling because it can produce a large suppression bandwidth.Additional measurement equipment,on the other hand,will raise the cost of the system as well as its complexity and analytical difficulty.Accelerometers or gyroscopes suffer from severe low-frequency drift and high-frequency noise.Existing control systems face extra control issues as a result of the accuracy of vibration estimation.Many enhanced control structures and optimized controllers,such as the Line

关 键 词：自适应光学 倾斜镜 滑模控制 扰动观测器 抖振 

分 类 号：TP273.2[自动化与计算机技术—检测技术与自动化装置]