月球软着陆的高精度自主导航与控制方法研究

Pinpoint Autonomous Navigation and Control for Lunar Soft Landing

提出了一种月球软着陆的高精度自主导航和控制方法.根据测距波束视线相对月面的几何关系,确定本体系的月心方向,组合利用测速仪获取的本体系三维速度确定本体系相对轨道系的姿态、速度及高度,并根据确定的参数性质选取适应的制导和控制方法.算法基于直接测量数据确定和控制姿态、高度和速度,不受惯性导航误差的影响,可以有效地提高姿态、速度与高度的确定精度和控制精度.数学仿真表明了算法的有效性.

A pinpoint autonomous navigation and control algorithm for lunar soft landing is presented in the paper. In the algorithm, first, the direction of landing spacecraft relative to the lunar center is determined according to the geometry relation of several ranging beams relative to the lunar surface. Second, attitude, velocity and altitude relative to the orbit reference frame are determined by combining the veloci- ty vector provided by the velocimeter in the body reference frame. Third, the adaptive guidance and con- trol method is selected based on the character of determined parameter. The algorithm can determine and control parameters of attitude, velocity and altitude based on direct measurement data and can improve the estimation and control accuracy of attitude, velocity and altitude, and can＇ t be affected by the inertial navigation error. Finally, the presented algorithms are validated by mathematical simulations.