小行星动能撞击自主导航与制导方法研究

Autonomous Navigation and Guidance for Asteroid Kinetic Impact Mission

针对近地小行星精确撞击任务需求,提出了一种小行星高精度撞击自主导航、制导与控制(Guidance Navigation&Control,GNC)方法,包括高精度的小行星中心视线提取、基于小行星中心视线测量的高精度自主相对导航及迭代预测制导。该设计利用小行星中心视线测量实现了在垂直于视线方向上撞击器相对于小行星位置和速度的精确估计,在沿视线方向上撞击器相对位置和速度存在误差的情况下利用迭代预测制导实现了高精度撞击。数值仿真表明,所提出的方案能够实现50 m级近地小行星4 m级撞击精度,满足了任务要求。

According to the requirements of near-Earth Asteroid kinetic impact mission,an autonomous GNC scheme is proposed,which contains the high-precision extraction method for the line of sight(LOS) of the asteroid center,high-precision autonomous relative navigation based on LOS measurement of the asteroid center,and iterative prediction guidance method. In this scheme,the LOS measurement of the asteroid center is used to estimate the relative position and velocity between the impactor and the asteroid in the direction perpendicular to the LOS. Although the elative position and velocity errors along the LOS are not estimated,the high-precision impact can be realized by the iterative prediction guidance method. The mathematical simulation shows that the proposed scheme can ensure the impactor to hit a near-Earth asteroid with the diameter 50 meter,the impact accuracy is better than 4 meter,which meets the mission requirements.