自主的高精度相对控制是实现卫星编队任务的关键技术,自主性要求控制器尽可能只利用星载设备所能提供的测量信息以减少星间通信量,高精度要求控制器连续的消除干扰力、期望轨迹推演以及参考星轨道控制与机动所造成的跟踪误差,为此,本文推导了描述星间相对运动的完整动力学模型以及对期望轨迹的跟踪误差模型,基于Lyapunov方法设计了自适应控制器,并证明了此控制器可以保证闭环系统的最终跟踪误差小于指定的界。本文给出的控制器仅需要星间的相对位置和相对速度测量,不需要主星的轨道参数、轨道位置和轨道机动信息,从而具有较高的自主性。仿真结果表明本文给出的控制器可以完成对期望轨迹的跟踪。
Autonomous accurate relative control is a key technique for formation flight missins, and requires that the controller only utilizes information provided by spacecraft-borne relative navigations sensors to continuously cancel the tracking errors resulted from disturbances, the propagation of the desired trajectory and the orbit control and maneuver of the reference. The full nonlinear relative dynamics of the follower with respect to the leader in an elliptic reference orbit is derived and the dynamics of the tracking error relative to the desired trajectory is given. An adaptive control law is derived based on Lyapunov theory and proved to guarantee global uniform ultimate boundedness of the closed-loop system. The controller in this paper requires only the relative position and velocity measurements and is independent of the leader' s position, orbit parameters and maneuvers, thus reducing inter-satellite communication burden. Simulation results are presented to illustrate the effectiveness of the control law.