航天器的有限时间时变滑模姿态控制方法设计

A Novel Finite-Time Sliding Mode Attitude Controller for Spacecraft

本文研究具有参数不确定性和外部扰动的航天器姿态控制问题.针对修正罗德里格参数表征的航天器姿态模型提出一种有限时间时变滑模函数,在此基础上设计一种有限时间收敛的滑模姿态控制方法,并证明其稳定性,给出控制参数的设计方法.该方法在保证系统渐近稳定的前提下,不仅能够实现姿态跟踪误差在有限时间内收敛,而且能够实现姿态跟踪误差在设定的时间收敛,且全局具有滑模动态确定的系统响应.通过仿真结果验证本文提出方法的有效性.

The problem of spacecraft attitude control is investigated in this paper. To solve this problem, a finite-time sliding mode control strategy is proposed based on a finite-time time-varying sliding manifold in the present of uncertainty and external disturbance. The stabilization is proved and the parameter selec- tion method is given. By using the proposed control strategy, the closed-loop system is asymptotically sta- ble and the convergence time is finite. In addition, the attitude tracking error can converge in a given time. Consequently the dynamic response of the closed-loop system is determined by the sliding mode dy- namics. Numerical simulations are finally provided to illustrate the performance of the control strategy.