挠性航天器轨控期间姿态容错控制

Fault tolerant attitude control of flexible spacecraft during orbit control

轨道调控期间,轨道控制推力会对挠性航天器的质心运动与姿态运动产生影响。针对轨道控制期间挠性航天器姿态控制系统的执行机构故障问题,提出了一种基于扩张状态观测器(extended state observer,ESO)的滑模容错控制算法。该算法将执行器故障,系统干扰及参数摄动量视为未知动态,通过设计相应的扩张状态观测器,能有效的实现对滑模状态量及未知动态的估计;在此基础上,利用未知动态的估计信息,设计了滑模容错控制控制律。最后,针对轨控期间反作用飞轮故障的挠性航天器姿态系统进行了仿真研究,仿真结果表明该算法能够有效处理执行器故障并使闭环系统稳定。

The orbit control force would generate disturb torque which has impacts on the centroid and attitude motion of flexible spacecraft during spacecraft orbit maneuver. A sliding mode fault tolerant control approach was proposed based on an extended state observer（ ESO） for the flexible spacecraft attitude control system with actuator faults during orbit control. In this approach,unknown actuator faults,internal and external disturbance,and parameter perturbation are considered as unknown dynamics. Based on the ESO design approach,sliding mode and unknown dynamics were effectively estimated,and sliding mode fault tolerant control approach was designed by using the estimating information. At last,the simulation results of flexible spacecraft were presented to demonstrate the effective of this approach.