自由漂浮双臂空间机器人基于速度滤波器的惯性空间轨迹跟踪鲁棒控制

Robust Control Based on Velocity Filter of Free-floating Dual-arm Space Robot System in Inertial Space

针对末端所持载荷参数未知的自由漂浮双臂空间机器人系统,提出了基于速度滤波器的鲁棒控制方法.利用拉格朗日方法进行运动学及动力学分析,建立了双臂空间机器人系统欠驱动形式的动力学模型.借助于增广变量法,证明了可将空间机器人系统的增广广义Jacobi矩阵及动力学方程表示为一组组合惯性参数的线性函数.在此基础上引入速度滤波器,设计了双臂空间机器人基于速度滤波器的惯性空间轨迹跟踪鲁棒控制方案.该速度滤波器可利用实测位置误差生成末端爪手的伪速度信号,有效避免了相关速度信号的实时测量与反馈.该方案的显著优点在于,不需要测量、反馈末端爪手的移动速度和加速度,同时有效消除了控制过程中的抖振现象.平面自由漂浮双臂空间机器人系统的数值仿真验证了算法的有效性.

Abstract The robust system with uncertain control scheme based on velocity filter of free-floating dual-arm space robot payload parameters was studied. Through the Lagrangian approach, the dynamic equation of the free-floating space robot was modeled as under-actuated system. With the augmentation approach, it was demonstrated that the dynamic equations and the augmented generalized Jacobi matrix of the system can be linearly dependent on a group of inertial parameters, respectively. Based on the results, a robust controller based on velocity filter was developed for dualarm space robot system with uncertain payload parameters to track the desired trajectories in inertial space. Ascribe to the pseudo-velocity signal acquired through the velocity filter, the proposed control scheme with only accurate positions of the joints and the end-effectors feedback avoid measuring thevelocity and acceleration of the end-effectors. And it can avoid the control chatter effectively at the same time. The effect of the controller is testified by computer simulation.