由于强非线性、强耦合和强时变等特征，柔性空间机器人的稳定精细控制问题一直是一个重大挑战。轻质小型化机器人受空间及重量限制，其关节柔性通常不可忽略，这部分柔性主要是由谐波减速器和力矩传感器的柔性造成的。传统的运动学控制在空载时能保持稳定，但是对大负载、快速运动时的适应性差，严重时机械臂抖动剧烈甚至发散。针对以上特征，提出了一种基于非线性干扰观测器和动力学极点配置的柔性空间机器人在轨精细操作控制方法。仿真实验证明，该方法可以有效地抑制柔性激振，保证响应的快速性和准确性，同时有较好的鲁棒性，能够适应不同类型扰动的影响和末端环境柔顺控制的要求，对工程应用具有一定的参考意义。
Due to characteristics such as strong nonlinearity, strong coupling and strong time-variation, the subtle stability control of flexible space robots has always been a major challenge. Limited by space and weight, the joint flexibility of lightweight miniaturized robots cannot be ignored, which is mainly caused by the flexibility of the harmonic reducer and the torque sensor. Traditional kinematics control can keep it stable in no-load states, while has poor adaptability to large loads and fast movement. In serious situations, the manipulator shakes violently, or even diverges. In view of the above problems, this paper proposes a precise operation control method for on-orbit flexible joint space robots based on a nonlinear disturbance observer and dynamics pole assignment. The simulation results show that this method can effectively suppress the flexible excitation, and ensure the rapidity and accuracy of the response; moreover, with good robustness, it can adapt to the influence of different types of disturbances and the requirements of terminal environment compliance control, providing reference for engineering application.
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