对翻滚非合作目标终端逼近的姿轨耦合退步控制

Coupled backstepping control for spacecraft to approach with a tumbling non-cooperative object during the final phase

摘要:

为在空间操控任务中实施对翻滚非合作目标的安全逼近与抓捕,论文建立了描述航天器近距离相对运动的六自由度动力学模型,通过对模型的分析,提出了摄动引起的耦合和动力学耦合．针对模型的非线性和时变性,对非线性高阶项进行多步递推得出系统化的积分退步控制器,并基于李雅普诺夫稳定性理论证明了控制器的全局渐进稳定．考虑到失控目标的旋转特性,提出一种沿最大惯量轴方向的直线型同步自旋逼近策略以保证航天器在逼近过程中的安全性．通过数值仿真验证了逼近策略的正确性以及控制律的有效性．

Abstract:

To insure the safety of autonomous approaching and capturing of a non-cooperative tumbling target in the on-orbit operating missions, 6 DOF dynamics model of relative translation and rotation is established to describe the relative motion of two spacecrafts in close distance, and the perturbation induced coupling and dynamic coupling existing in the model are presented to make clear what the coupling effect is. Due to the effects of time-varying and nonlinear terms in the model, the systemized integrator backstepping controller is derived after multi-step recursion with regard to the nonlinear high-order terms. The stability of the controller is proved to be global asymptotic stable based on the Lyapunov’s stability theory. With the consideration of rotating characteristic of the target satellite, a linear synchronization rotating approach strategy along the maximum inertial axes is presented to ensure the safety during the final approach. The validity of approach strategy and the effectiveness of controller is verified by the numerical simulation.