针对火星探测环绕段自主导航需求，结合初始轨道参数及光学导航相机拍摄的火星图像，提出了一种基于火星本体的高精度自主导航方法。该方法首先利用初始轨道参数得到火星在导航相机像平面下的投影图，然后将该投影图与导航相机拍摄的火星图进行匹配融合得到火星的边缘图，后利用该边缘图进行精确椭圆拟合，继而可实现器-火视线距和视线矢量的测量，在算法仿真过程中充分考虑到了工程实现中可能会遇到的图像旋转、平移及尺寸变换问题，仿真结果表明：提出的利用先验信息的图像融合测量算法较单独利用火星图像进行导航测量的方法，精度和可靠度均有较大提升，可满足火星探测环绕段的任务需求。

Demand for autonomous navigation for mars exploration during the surround segment, a high-precision autonomous navigation method using Mars ontology was proposed based on the initial orbital parameters and the Mars image was taken by the optical navigation camera. The method first used the initial orbital parameters to obtain a projection of Mars in the camera phase plane, then matched the projection map with the Mars image to get the edge map of Mars, using the edge map for accurate ellipse fitting to achieve detector-Mars line of sight distance and line of sight vector measurement. In the process of algorithm simulation, the problems of image rotation, translation and size transformation that may be encountered in engineering implementation were fully considered. The simulation results show that the proposed image fusion measurement algorithm using prior information, the accuracy and reliability is improved more than the navigation method using mars image alone, which can meet the mission requirements of Mars exploration during the surround segment.