空间机器人目标捕获的自适应零反作用控制

Adaptive Reactionless Control for Target Capture of Space Robots

针对目标捕获后空间机器人的机械臂反作用力对其基座的姿态扰动问题,提出了一种自适应零反作用控制方案。首先,针对目标捕获带来的动力学不确定性,设计了一种激励矩阵调节的固定时间并行学习算法。该算法可在放松持续激励条件的同时,使参数估计的收敛率与回归通道中未知的激励水平无关,因此不同量级惯性参数的估计可在相近时间内收敛。此外,通过分别设计基座姿态控制器与机械臂轨迹跟踪控制器提出了一种具有输入扰动补偿的有限时间零反作用控制方法,能够在机械臂跟踪末端期望位姿轨迹的同时维持基座姿态的稳定性。仿真结果验证了该方案的有效性。

An adaptive reactionless control strategy is presented for free-floating space robots subject to parameter uncertainties and unknown bounded disturbances.Firstly,a novel fixed-time concurrent learning algorithm is proposed to relax the persistent excitation condition and make the convergence rates of parameter estimations independent of the excitation levels in regressor channels.As a result,the accurate estimations of inertia parameters with different magnitudes can be obtained at the same time.Then,a finite-time zero reaction control method with input disturbance compensation is proposed by designing a pedestal attitude controller and a manipulator trajectory tracking controller respectively,which can maintain the stability of the pedestal attitude while tracking the desired pose trajectory of the end of the manipulator.The simulation results demonstrate the effectiveness of the proposed control scheme.