事件驱动的卫星编队姿态分布式协同控制

星间信息交互是卫星编队姿态协同控制的基础.为降低姿态协同控制对星间交互的信息量,满足资源和通信带宽受限等约束,在卫星编队Euler-Lagrange姿态动力学模型的框架内,提出了一种基于事件驱动的相对姿态分布式自适应控制算法.通过设计含有星间状态偏差、关联矩阵等的事件驱动函数,当该函数值满足条件时触发事件、更新数据,在非触发时间内利用触发时刻的信息设计控制算法,从而将卫星编队姿态一致性协同控制转化为事件驱动控制问题,有效降低了控制输入更新频次及星间信息交互量.基于Lyapunov理论证明了在事件驱动自适应控制器作用下,领航者—跟随者卫星编队系统是全局渐近稳定的.并证明了事件触发时间序列不会产生Zeno现象,即事件触发间隔时间存在下界.进行数值仿真验证事件驱动自适应控制算法的有效性,并将其与传统自适应控制算法相比较,仿真结果表明,所设计的控制算法在保证闭环系统控制性能的前提下,显著降低了控制输入更新频次和星间交互信息量,满足星上能量和星间通信能力等约束.

Event-triggered distributed attitude coordination control of satellite formation

Inter-satellite information interaction is the basis of satellite formation attitude coordination control. To reduce the amount of inter-satellite interaction information and meet the constraints of resource and communication bandwidth limitation, an event-triggered relative attitude distributed adaptive control algorithm is proposed based on the Euler-Lagrange attitude dynamics model of satellite formation. Event-triggered function is designed by utilizing inter-satellite state deviation and associative matrix, etc. Event is triggered and data is updated when function value satisfies the condition, and control algorithm is designed by utilizing information of event time during non-event time, thus the satellite formation attitude consensus coordination control is transformed into an event-triggered control problem. Update frequency of control input and the amount of inter-satellite interaction information are reduced effectively. Leader-follower satellite formation system using proposed control algorithm is proved to be globally asymptotic stable based on the Lyapunov theory. Event-triggered time sequence will not produce Zeno behavior, i.e. a lower bound exists during inter-event time. Numerical simulations were performed to verify the effectiveness of event-triggered adaptive control algorithm, which was in turn compared with a conventional one. Simulation results show that the proposed control algorithm significantly reduces update frequency of control input and the amount of inter-satellite interaction information, meet the constraints of energy on board and inter-satellite communication ability, and ensures control performance of closed loop system at the same time.