滑模变结构控制的月球着陆舱姿态控制系统设计  

The Design of Lunar Lander Attitude Control System based on Variable Structure Control with Sliding Mode

作　　者：常晓飞[1] 闫杰[1] 段丽娟[1] 

机构地区：[1]西北工业大学航天学院,陕西西安710072

出　　处：《火力与指挥控制》2009年第6期75-78,共4页Fire Control & Command Control

摘　　要：在我国的探月计划中,要实现月球探测器软着陆于月球表面。在分析月球着陆舱软着陆段的飞行任务对于姿态控制要求的基础上,基于滑模变结构控制方法,根据实际姿态角和期望姿态角的偏差,给出了线性滑动模态面的切换方程,采用指数趋近律和边界层削抖的方法,推导出期望控制力矩的计算公式。并研究了姿控发动机的配置特点和点火逻辑,给出了由期望力矩计算实际控制力矩的方法。仿真结果表明,该姿态控制系统能迅速地将着陆舱跟踪到期望姿态,着陆舱经过514 s飞行,在距月面2 km处将速度减为零,将姿态调整到垂直向下,完成了飞行任务。飞行轨迹比较平滑,具有较好的鲁棒性和自适应性。In the chinese lunar exploration project, soft landing of the lunar explorer on the lunar surface is to be realized. The control requirement in the powered descending phase of thequnar lander is analyzed in the paper. The switch equation for linear sliding surface is deduced by the result of the deflection between the real attitude angles and the anticipant attitude angles based on variable structure control with sliding mode. The formula of anticipant control moment is deduced by adopting the method of exponent reaching law and twitter reducing of boundary layer. The configuration character and ignition logic of the attitude control engine are studied, and the method of calculating actual control moment by anticipant moment is given. The simulation results show that attitude control system can adjust the lander to anticipant attitude. The lander velocity reduces to zero at the point that is 2 km far away from the lunar surface after flying 514 s, and the attitude is tuned vertically downwards, it implements the flying mission. The flight track is smooth. Therefore, The attitude control system possesses good robustness and adaptability.

关 键 词：软着陆 姿态控制系统 滑模变结构控制 

分 类 号：V476.3[航空宇航科学与技术—飞行器设计]