含有参数不确定性的挠性航天器姿态跟踪滑模控制

Sliding-mode attitude tracking control for a flexible spacecraft with parametric uncertainty

中文关键词  滑模控制  挠性航天器  姿态跟踪  参数不确定性  观测器

英文关键词  sliding-mode control  flexible spacecraft  attitude tracking  parametric uncertainty  observer

中文摘要

      对有不确定参数的挠性航天器姿态跟踪控制, 提出了一种基于滑模控制的姿态跟踪控制律. 挠性航天器动力学采用混合坐标法进行建模; 构造挠性模态观测器对挠性模态变量进行观测. 基于Lyapunov稳定性原理得到含有挠性模态观测器的滑模控制律, 并给出了全局渐近稳定性的证明. 对各个仿真结果进行比较, 显示出本文提出的滑模控制律针对航天器惯量阵不确定性具有良好的鲁棒性, 而且具有较强的扰动抑制能力.

英文摘要

      For the attitude tracking control of a flexible spacecraft with parametric uncertainty, an attitude tracking control law is presented based on the sliding-mode control. The dynamic model of the flexible spacecraft is built by the hybrid coordinate method; and a flexible modal-observer is developed for observing the flexible variables of this model. A sliding-mode control law containing the flexible modal-observer is then obtained by using Lyapunov approach; the closedloop system under this control is proved to be global asymptotically stable. Comparison of simulation results also shows that this control law provides high robustness to the inertia-matrix uncertainty of the spacecraft and attenuates the external disturbance well.