基于时变增益ESO的多航天器SO(3)姿态协同控制

针对多航天器姿态协同控制问题，基于特殊正交群（SO（3））研究了存在干扰情形下的控制设计方法。结合有向通信拓扑建立了多航天器SO（3）模型，在此模型的基础上提出了一种时变增益扩张状态观测器（ESO）对系统的总干扰进行估计，削弱了常值增益ESO的峰化现象。利用相邻航天器的信息给出了旋转矩阵形式的协同指令，进一步基于SO（3）方法设计了协同控制器。同时采用ESO的输出在所设计的控制器中对系统的干扰进行补偿，从理论上给出了ESO的收敛性以及闭环系统的稳定性证明，保证多航天器系统能够实现稳定协同。仿真结果验证了本文方法的有效性和快速性。 

Cooperative attitude control on SO(3) for multiple spacecraft with time-varying gain ESO

This paper is concerned with the cooperative attitude control of multiple spacecraft, and the control design method on special orthogonal group (SO(3)) with disturbance is studied. The multiple spacecraft system is modeled using SO(3) method and directed communication topology. Then, a time-varying gain extended state observer (ESO) is proposed to estimate the total disturbance in the system, and it lessens the peaking phenomenon. The control commands are formulated in the form of rotation matrices using the information of adjacent spacecraft. Thus, the cooperative controller based on SO(3) method is designed, and at the same time ESO output is used to compensate the disturbance on the system. The convergence of the ESO and the stability of the closed-loop system are analyzed in this paper, which shows that the attitudes of the multiple spacecraft could reach stable consensus. Simulation is conducted to verify the effectiveness of the proposed method.