航天器姿态机动优化容错控制

Optimal Fault-tolerant Control for Spacecraft Attitude Maneuver

针对存在未知时变惯量不确定性、外部干扰力矩和执行机构衰退故障的非刚体航天器系统,研究了非刚体航天器自适应优化容错控制问题。首先,为了根据误差变量优化控制增益,设计一种动态增益调整函数实时优化控制增益;然后,基于非线性鲁棒控制方法、动态增益函数调整方法、自适应方法、容错控制理论与参数估计方法,提出一种新颖的自适应优化姿态跟踪容错控制器。所设计的控制器克服了执行器故障、惯量不确定性以及外界干扰的影响,保证航天器姿态及角速度能够跟踪时变的参考轨迹,实现跟踪误差系统最终一致有界稳定;最后,数字仿真结果验证了所提出方法的有效性,而且与已有控制方法相比,该方法具有更高的控制精度和稳定性。

This paper investigates an adaptive optimal f{ault tolerant control problem {or non rigid spacecra{t attitude maneuver with unknown time varying inertia,external disturbance and actuator fading. Firstly, a dynamic gain adjustment {unction is de signed to optimize the control gain according to the error variables. Secondly,based on nonlinear robust control, the dynamic adjustment function, adaptive approach,fault- tolerant control theory and parameter estimation method, a novel adaptive optimal at titude tracking fault-tolerant controller is proposed. The proposed controller overcomes the influence of actuator fault,inertia un certainty and external disturbance, andit can guarantee the attitude and angular velocity to track the reference time varying trajectory and guarantee that the uniformly ultimately bounded stability of the error system is achieved. Finally, simulation results validate the effectiveness of the presented control algorithm and demonstrate higher control precision and better performance of the designed control approach compared with existing methods.