基于扩张状态观测器的航天器自适应姿态控制

Adaptive Controller for Spacecraft Attitude Maneuver Based on Extended State Observer

针对航天器三轴姿态大角度机动时动力学特性耦合强烈的情况,同时考虑外界干扰及执行器的不确定性,根据扩张状态观测器的相关理论,提出了航天器姿态机动的一种自适应输出反馈控制策略。首先,采用动量矩定理和欧拉法建立了航天器的姿态动力学模型。然后,在此基础上,利用扩张状态观测器能够准确地获取航天器三轴间非线性耦合及其他未知的外界干扰信息的能力,设计了一种仅需要姿态角测量值的自适应输出反馈控制律,使航天器在大角度姿态机动的同时能够通过自适应律补偿控制力矩的输出偏差。仿真结果表明,在多种任务模式下,航天器都可以很好地完成姿态机动任务,从而验证了控制律的正确性和有效性。

To deal with spacecraft three-axis large attitude maneuver with the external disturbances and actuator uncertainties,a new adaptive output feedback controller was presented based on the extended state observer.Firstly,an attitude dynamic model by the Momentum theorem and Euler method was established.Secondly,based on the fact that the extended state observer could minimize the nonlinear coupling and external disturbances,the adaptive output feedback control strategy was developed only with the attitude angle output,which could compensate the control toque error during the large angle attitude maneuver.Finally,simulation results show that the precise attitude maneuver can be accomplished and the angles can converge to the desired states for different cases.