针对四反作用飞轮配置的刚体航天器执行机构故障以及外部干扰等问题,提出一种姿态容错控制分配算法.该方法通过设计滑模观测器,实现在有限时间内对执行机构故障与外部干扰的精确重构；特别地,应用Lyapunov稳定性理论证明了所设计的控制器能够在有限时间内实现对闭环姿态的全局渐近稳定控制,且该控制策略可实现对反作用飞轮故障与外部干扰的鲁棒性.此外,采用计算量较小的基序最优控制分配方法快速实现了期望控制力矩到四反作用飞轮指令控制力矩分配.最后,针对某型号航天器以及各种反作用飞轮故障进行数值仿真,仿真结果表明所设计过驱动航天器飞轮故障重构与姿态容错控制方法能够在线、及时、精准地完成故障重构与控制分配.%A novel attitude control scheme is proposed for a rigid spacecraft with four reaction wheels as actuators in the presence of actuator failure and external disturbances. More specially, a sliding mode observer is firstly designed to accurately reconstruct reaction wheel faults in finite time, and it is proved from the Lyapunov analysis that the satellite attitude and the angular rate are governed in finite time to be asymptotically stable, and the proposed control law can be utilized to deal with actuator faults and external disturbances. In addition, the base sequence optimal control allocation method is also applied to accomplish the distribution from desired control torque to the commanded control torque of four reaction wheels. Finally, a numerical simulation example for a spacecraft attitude control system is included to illustrate effectiveness and feasibility of the proposed control scheme.
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