一种基于视向信息的航天器自主导航方法  

An Autonomous Navigation Method for Spacecraft Based on Line-of-Sight Information

作　　者：张念程 戴振东 吴英浩 孙昭行 ZHANG Niancheng;DAI Zhendong;WU Yinghao;SUN Zhaoxing(Shanghai Aerospace Control Technology Institute,Shanghai 201109)

机构地区：[1]上海航天控制技术研究所,上海201109

出　　处：《上海航天(中英文)》2024年第S2期200-210,共11页Aerospace Shanghai(Chinese&English)

摘　　要：鉴于我国地理限制对全球监测站布局的影响,本文提出了一种航天器自主导航方案,旨在减少对地面站测控站的依赖,以提高航天器的自主导航能力。该方案利用空间在轨目标(RSO)的视向信息,通过观测RSO实现航天器的自主定位。首先,系统处理图像,提取空间目标和恒星的像点坐标。随后,通过星图识别算法确定恒星的赤经赤纬参数,并确定目标与恒星之间的夹角。基于恒星与空间目标的几何关系,计算目标的赤经赤纬及其误差协方差矩阵。最终,选择轨道动力学模型作为状态更新的基础,并将空间目标的视线方向信息作为观测方程,通过应用扩展卡尔曼滤波技术(EKF)估算航天器的状态。另外,本文还分析了影响定位精度的因素。仿真结果表明,该方案稳态后的位置误差均方根为123.44 m,速度误差均方根为0.13 m/s。Considering the impact of China's geographical constraints on the layout of global monitoring stations,this paper proposes an autonomous navigation scheme for spacecraft aimed at reducing dependence on ground stations and enhancing the spacecraft's autonomous navigation capabilities.The scheme leverages the line-of-sight information of on-orbit space targets(RSO)to achieve autonomous positioning of the spacecraft.Initially,the system processes images to extract the image coordinates of space targets and stars.Subsequently,star identification algorithms are employed to determine the right ascension and declination parameters of the stars and to ascertain the angles between the targets and stars.Based on the geometric relationship between stars and space targets,the right ascension and declination of the target,as well as its error covariance matrix,are calculated.Ultimately,an orbital dynamics model is selected as the basis for state updates,and the line-of-sight direction information of space targets is used as the observation equation.The extended Kalman filter(EKF)technique is applied to estimate the spacecraft's state.Simulation results indicate that the method achieves a root mean square(RMS)position error of 123.44 m and an RMS velocity error of 0.13 m/s after reaching a steady state.Additionally,this paper analyzes the factors affecting positioning accuracy.

关 键 词：自主导航 空间目标 视向信息 视觉导航 扩展卡尔曼滤波器 

分 类 号：TN911.72[电子电信—通信与信息系统] TP391.9[电子电信—信息与通信工程]