双臂空间机器人关节运动的一种增广鲁棒控制方法

讨论了载体位置与姿态均不受控制情况下,漂浮基双臂空间机器人系统的控制问题.结合系统动量守恒关系进行的运动学、动力学分析表明,可以得到一组与适当选择的惯性参数呈线性函数关系的、欠驱动形式的系统动力学方程.以此为基础,并采用增广变量的思想,克服了通常情况下,空间机器人系统动力学方程关于系统惯性参数呈非线性关系的难点,针对双臂空间机器人末端爪手所持载荷参数不确定,但误差范围可确定的情况,设计了漂浮基双臂空间机器人关节运动的变结构鲁棒控制方案.该控制方案的优点在于,不需要反馈、测量漂浮基的位置、移动速度及移动加速度;与自适应控制方案相比,化积分运算为简单四则运算,计算量大为减少,有利于实时应用.通过对一个平面双臂空间机器人系统的数值仿真,证实了算法的有效性.

Robust Variable Structure Control for Free-Floating Space Robot System With Dual-Arms in Joints Space

In this paper,the kinematics and dynamics of free-floating space robot system with dual- arms are analyzed.It is shown that the dynamic equations of the system are nonlinearly depending on inertial parameters.In order to overcome these problems,the system is modeled as under-actuated robot system,and the idea of augmentation approach is adopted.It is demonstrated that the dynamic equations of the system can be linearly dependent on a group of inertial parameters.Based on the results,a robust variable structure control scheme for free-floating space robot system with dual- arms with uncertain inertial parameters to track the desired trajectory in joint space is proposed, and a planar space robot system with dual arms is simulated to verify the proposed control scheme. The advantage of the control scheme proposed is that it requires neither measuring the position, velocity and acceleration of the floating base with respect to the orbit nor controlling the position and attitude angle of the floating base.In addition to this advantage,it is computationally simple, more suitable for real time applications.