小天体撞击的自主光学导航方法

Autonomous Optical Navigation Algorithm for Small Body Impact Mission

针对小天体撞击任务中撞击器高精度导航的要求,在撞击器相对目标天体的位置和速度矢量夹角很小的任务条件下,研究了一种基于B平面坐标系的自主光学导航算法。该算法以目标天体图像中心点像素值为观测量,将撞击器位置和姿态欧拉角作为状态变量,设计了卡尔曼滤波器,对B平面内位置分量和相应姿态分量进行了高精度估计。蒙特卡洛数学仿真结果表明,该自主光学导航算法具有较高的精度和较强的稳定性。

Aiming at the high precision requirement of the orbit determination system, an autonomous optical navigation strategy based on B-plane coordinate system was investigated for a small-body impact mission, in which the angle between the target-relative position and velocity vectors could be ignored. The algorithm used images of the target body to update target relative state information. This involved using the object center-of-figure data as the observations and then processing the data through a Kalman filter to update the impactor position and attitude components in the B-plane coordinate. Monte Carlo simulations demonstrate the feasibility of the approach, including the numerical accuracy and stability.