基于高阶滑模观测器的自适应时变滑模再入姿态控制

针对再入飞行器鲁棒姿态控制问题, 提出一种基于高阶滑模观测器的自适应时变滑模控制器设计方法. 首先, 设计了一种时变滑模面, 并在此基础上推导了相应的时变滑模控制律, 其中滑模控制中切换增益通过一种自适应算法获得, 消除了控制器设计过程中对系统不确定性上界已知的要求; 然后, 利用高阶滑模观测器对控制器设计过程中用到的姿态角导数信息进行观测, 同时能够获得系统扰动估计值, 从而构造一种基于观测器的控制器形式; 最后, 通过仿真验证了所提出的控制算法在提高再入飞行器姿态控制精度以及系统鲁棒性方面的有效性.

High-order sliding mode observer based adaptive time-varying sliding mode for re-entry attitude control

A high-order sliding mode observer based time-varying sliding mode control strategy is presented to address the robust attitude control problem of uncertain re-entry vehicle. Firstly, a time-varying sliding surface and the corresponding sliding control law are designed respectively, in which the switching gains are obtained through an adaptation scheme. Hence, the requirement of a prior knowledge of the upper bound on the model uncertainty is removed. Further, a high-order sliding mode observer is adopted to get the information of the attitude angle derivatives and estimate the system disturbances as well. Thus, an observer based control scheme is constructed. Finally, a numerical simulation is employed to illustrate the effectiveness of the proposed strategy in improving the attitude control accuracy as well as the system robustness.