基于扰动观测器的机器宇航员协调操作阻抗控制

Coordinated Impedance Control of Robonaut Based on Disturbance Observer

针对未知干扰环境下机器宇航员执行协调操作任务的高精度控制要求,提出一种基于扰动观测器的协调操作阻抗控制算法.首先分析操作物与机器宇航员的几何约束和力约束关系,建立机器宇航员与操作物的统一动力学模型;其次利用机器人广义动量,设计适用于机器宇航员协调操作系统的动量扰动观测器;然后结合统一动力学模型,设计基于扰动观测器的机器宇航员协调操作阻抗控制算法;最后通过仿真对控制方法开展验证.结果表明,当臂杆受未知干涉力影响时,操作物的位置误差可被控制在10-5 m的量级内.所提出的算法有效减小了未知干涉力对操作物位姿控制精度的影响,保证了协调操作任务的高精度控制.

To meet the high-accuracy control requirements of the coordinated operation task performed by the Robonaut under unknown interferences, a coordinated impedance control method based on disturbance observer is proposed. Firstly,geometric constraints and force constraints between the object and the Robonaut are analyzed to establish a unified dynamics model of the object and the Robonaut. Secondly, a momentum disturbance observer is designed for the coordinated control system of the Robonaut based on the generalized momentum of the robot. Thirdly, an impedance control method is designed for coordinated operation of the Robonaut based on the disturbance observer, combining with the unified dynamic model.Finally, a numerical simulation is carried out to verify the proposed method. Results show that the position error of the object is controlled within the order of 10-5 m, when the arms are influenced by unknown interferences. The proposed method effectively reduces the influence of the unknown interferences on the accuracy of the object pose control, and ensures the high precision control of the coordinated operation task.