基于轨迹跟踪的航天器姿态自适应鲁棒控制

Adaptive Robust Attitude Control of Spacecraft Based on Trajectory Tracking

针对存在不确定惯量和空间环境干扰的挠性航天器姿态大角度快速机动控制问题,提出了一种受细胞膜放电模型启发的自适应鲁棒姿态控制器设计方法.首先,为了快速完成姿态机动任务,并尽可能少激发挠性帆板振动,在挠性航天器运动学和动力学分析的基础上,提出了基于预先规划姿态运动轨迹且对不确定惯量具有自适应能力的自适应鲁棒控制器.在此基础上,为了改善机动过程中姿态跳变使系统指向精度和稳定度变差的问题,基于细胞膜放电的动力学模型设计了一种改进型自适应鲁棒控制器.所提出的控制器能够保证闭环系统渐进稳定;当惯量估计误差有界时,对于任意初始跟踪误差,该控制器可以保证姿态跟踪误差一致终值有界.仿真结果表明了所提出的改进型自适应鲁棒控制器的有效性.

In order to implement the rapid attitude maneuvering control of flexible spacecrafts in large-angle mobility mode in the presence of inertia uncertainties and external disturbances in space, inspired by the model of cell membrane discharge, an adaptive robust attitude controller is proposed. In the investigation, first, the kinematics and dynamics of flexible spacecraft are analyzed. Then, an robust control law, which is based on the pre-planned attitude trajectory and is adaptive to uncertain inertia, is put forward to improve the rapid attitude maneuvering performance and suppress the vibration of flexible panels. Finally, to avoid the degradation of pointing accuracy and stability due to the attitude jump during the maneuvering, an improved adaptive robust controller is designed based on the dynamic model of cell membrane discharge. It is proved that the proposed controller guarantees the asymptotical stability of the closed-loop system. Moreover, under bounded inertia estimation errors, uniformly-ultimate bounded tracking errors can be obtained with the controller. Simulation results verify the effectiveness of the proposed controller.