软着陆小行星的自主导航与制导

讨论了软着陆小行星的自主导航与制导问题，首先给出了一种使用星上光学相机和激光雷达的自主导航方法，测量探测器相对着陆点的距离与速度；接着提出了一种自主软着陆的制导方案，为了保证垂直软着陆，事先规划了满足约束的理想下降高度与速度轨迹，并设计滑模变结构控制器跟踪理想轨迹，实现在小行星表面垂直软着陆。最后通过数学仿真验证了提出的自主光学导航与制导方法的可行性。

Autonomous navigation and guidance for soft-landing asteroid

In this paper,we discussed the problem of autonomous optical guidance and navigation for descent to a small body.First,an autonomous optical navigation method using on board optical camera and laser radar was given to measure relative position and velocity between probe and asteroid,and then an autonomous guidance strategy was proposed.A prescribed altitude and velocity profile was defined to ensure vertical soft landing.A sliding mode controller was designed to track prescribed altitude and velocity profile for safely soft landing on surface of small body.Finally,simulations are conducted to verify the guidance precision.The effects for the guidance precision of varies perturbation including observation errors,initial state errors,parameter errors is discussed.