外部扰动下空间机器人基于扰动观测器的鲁棒控制  

ROBUST CONTROL OF SPACE ROBOT BASED ON DISTURBANCE OBSERVER UNDER EXTERNAL DISTURBANCE

作　　者：尤鑫烨 陈力[1] You Xinye;Chen Li(College of Mechanical Engineering and Automation,Fuzhou University,Fuzhou 350116,China)

机构地区：[1]福州大学机械工程及自动化学院,福州350116

出　　处：《动力学与控制学报》2021年第2期37-42,共6页Journal of Dynamics and Control

基　　金：国家自然科学基金资助项目(11372073,11072061);福建省工业机器人基础部件技术重大研发平台资助项目(2014H21010011)。

摘　　要：针对参数不确定及存在外部扰动的情况下,载体位置不控、姿态受控的漂浮基空间机器人末端抓手轨迹跟踪控制问题,提出了一种基于扰动观测器的鲁棒控制方法.结合动量守恒定律,采用拉格朗日第二类方程建立了系统动力学方程.假设外部扰动是随时间变化的未知量,设计了扰动观测器估计由外部干扰和参数不确定构成的总扰动,并基于估计的总扰动引入扰动补偿项,保证了系统的控制性能.根据Lyapunov稳定性理论,证明了文中所提出控制律的稳定性.该控制律能补偿由于参数不确定和外部扰动引起的总扰动,从而提高了系统的轨迹跟踪性能.所提出的控制方案与传统鲁棒控制方案相比,具有控制器结构简单,不需要测量机械臂角加速度及基座的位置、移动速度、移动加速度,系统所需的传感器数量少等优点.最后通过数值仿真模拟,验证了上述控制方案的有效性.A disturbance observer based robust control method is proposed to solve the trajectory tracking problem of the terminal grasp of a floating-based space robot with uncertain parameters and external disturbances.Based on the law of conservation of momentum,the second Lagrange equation is used to establish the dynamic equation of the system.As⁃suming that the external disturbance is an unknown time-varying variable,a disturbance observer is designed to estimate the total disturbance consisting of external disturbance and parameter uncertainty.Based on the estimated total distur⁃bance,a disturbance compensation term is introduced to guarantee the control performance of the system.The stability of the proposed control law is proved.The control law can compensate the total disturbance caused by parameter uncer⁃tainties and external disturbances,thus improving the trajectory tracking performance of the system.Compared with the traditional robust control scheme,the proposed control scheme has various advantages including a simple controller structure,no need to measure the hinge acceleration and the position,moving speed and acceleration of the base of the manipulator,and less sensors needed in the system.Finally,the effectiveness of the above control scheme is verified by numerical simulation.

关 键 词：空间机器人 外部扰动 扰动观测器 LYAPUNOV函数 鲁棒控制 

分 类 号：V448[航空宇航科学与技术—飞行器设计] TP242[自动化与计算机技术—检测技术与自动化装置] TP273[自动化与计算机技术—控制科学与工程]