含时变时延的卫星编队姿态协同自适应滑模L_2增益控制

L_2-gain based adaptive sliding mode coordinated attitude control of satellite formation with time-varying delays

针对带有时变通信时延和输入时延的卫星编队飞行姿态协同控制问题,考虑卫星转动惯量参数不确定性及干扰,提出了一种自适应滑模L2增益控制算法。该方法首先利用自适应参数辨识技术对由转动惯量参数不确定给系统带来的扰动上界进行估计,进而设计了含时变时延信息的滑模自适应控制器,构造Lyapunov-Krasovskii函数,从理论上证明了闭环系统在该控制器作用下可以协同达到渐进稳定。在此基础上,进一步考虑存在外部干扰的影响,定义包括外部干扰与自适应参数估计误差在内的广义干扰,设计了对广义干扰具有L2增益抑制作用且含时变时延信息的姿态协同控制器。最后,仿真结果表明了所提出的控制器的可行性、有效性。

With the consideration of communication time-varying delays and input time-varying delays, as well as parametric uncertainties and external disturbance, an adaptive sliding mode L2-gain attitude coordinated controller is proposed for satellite formation under a general undirected interaction topology. Firstly, an adaptive sliding mode con- troller is developed, in which the adaptive technique is employed to estimate the upper bound of the perturbation suf- fered from parametric uncertainties of the inertia matrix. A Lyapunov-Krasovskii function with information of time-de- lays is constructed to prove the asymptotic stability of the closed-loop system theoretically. Then, the controller is im- proved to ensure high robustness in the sense of L2-gain to the total perturbation from both error of parameter estimation and external disturbance, in which time-varying delays are also included explicitly. Numerical simu- lations demonstrate the effectiveness of the proposed attitude coordinated controller.