基于反步法与动态控制分配的航天器姿态机动控制

Backstepping and dynamic control-allocation for attitude maneuver of spacecraft with redundant reaction fly-wheels

中文关键词  航天器  反作用飞轮  反步法  二次规划  动态控制分配

英文关键词  spacecraft  reaction fly-wheel  backstepping  quadratic programming  dynamic control-allocation

中文摘要

      针对存在未知转动惯量与外部干扰的航天器姿态机动控制问题, 提出了一类基于反步法的鲁棒自适应控制器, 并利用Lyapunov方法分析了系统的稳定性; 考虑到作为执行机构的反作用飞轮存在冗余性, 进一步提出了一种基于约束最优二次规划的动态控制分配算法来实现指令到期望飞轮的指令分配, 克服传统伪逆法难以考虑飞轮动态特性、最大力矩等物理约束, 并能有效的抑制姿态敏感器的测量噪声和测量异常值, 实现控制力矩的平稳性. 最后, 将本文提出的控制方案应用于某型轮控刚体航天器的姿态机动任务中, 仿真结果验证了本文提出方法的可行性、有效性.

英文摘要

      We develop a robust adaptive controller based on the backstepping method for the attitude maneuver of the spacecraft with unknown rotational inertia and unknown external disturbances. The stability of the closed-loop system is validated by using Lyapunov analysis. In considering the redundancy of the actuators-the reaction fly-wheels, we propose a dynamic allocation algorithm based on the constrained optimal quadratic programming for distributing the control command to the proper fly-wheel. This eliminates the physical restrictions on the fly-wheel characteristics and the limitation of the maximal torque, which are required in the conventional pseudo-inverse method. In addition, it also effectively suppresses the measurement noises and rejects the abnormal data from attitude sensors, improving the smoothness of the control torque. The proposed scheme has been applied to control the attitude maneuver of a wheel-control rigid spacecraft. Simulation results validate the efficacy of the proposed method.