执行机构部分失效的挠性航天器多界依赖容错控制

Multi-bound-dependent fault-tolerant control for flexible spacecraft under partial loss of actuator effectiveness

针对挠性航天器在轨运行时受到的外部干扰,输入时滞以及执行机构部分失效问题,本文提出了一种基于不确定参数的鲁棒H_∞容错控制方法.首先,将执行机构部分失效容错控制问题转化为不确定参数的鲁棒控制问题.然后,设计了一个新型的多界依赖状态反馈鲁棒H_∞控制算法.此算法不仅依赖时滞积分不等式分割参数和时滞界信息,还依赖部分失效因子.因此,本文设计的控制器能同时实现对输入时滞的敏感,对部分失效故障的容错及对外部干扰的抑制.最后,通过一系列的仿真验证本文方法的有效性.

A fault tolerant control based on robust H--infinity control with uncertain parameters is proposed for an onorbiting flexible spacecraft in the presence of partial loss of actuator effectiveness,external disturbance and input delays.Firstly,the fault tolerant control with loss of actuator effectiveness is transformed into robust control with uncertain parameters.Secondly,a new multi-bound-dependent robust state feedback H--infinity control algorithm is designed.This algorithm is not only dependent on the decomposition coefficient of the time delay integral inequality and time delay bounds,but also depends on the partial failure factor.Therefore,the controller designed in this paper can be sensitive to the input delays,be tolerant to actuator partial failure and be rejective to external disturbance.Finally,the effectiveness of the proposed design method is demonstrated in a spacecraft attitude control system subject to loss of actuator effectiveness.