面向探月卫星景象导航的局部基准图制备

为了可靠制备月球卫星景象辅助导航和着陆过程中的月面局部基准图,分析了月面局部基准图制备过程中出现的相关问题和解决方法。结合"嫦娥二号"月球卫星测控和导航实际约束条件分析了各种误差的起因及限制方法,给出了基于美国月球勘测轨道飞行器相机(LROC)全月面基准影像图的月面局部基准图制备算法。实验结果表明,按照所提方法生成的局部基准图与"嫦娥二号"局部正摄投影图像面特征一致,由映射变换产生的图像坐标最大定位误差为7.065 1m,观测图尺寸为20km×20km时的最大形变偏差为6.18m,正摄投影图像面特征和定位偏差均能够满足月球卫星景象导航定位精度的要求。

Preparation of local base map for lunar orbiter scene matching navigation

To prepare a lunar local base map for the lunar orbiter scene aided navigation and landing,the preparing method and related problems for the lunar local base map were researched in this paper. Based on real data from Chang-E 2 mission, error generation and restriction ways for the local base map were analyzed combining with constraints from measurement, tracking and navigation. A set of algorithm for preparing the lunar local base map was proposed according to the global base map by Lunar Reconnaissance Orbiter Camera(LROC) in LRO mission. Experimental results show that pixel features from the generated local base map are consistent with corresponding features from Chang-E 2 orthographic projection images,the maximum coordinate location error by projection is 7.065 1 m, and the distortion error is 6.18 m for the observing map size in 20 km×20 km. These results meet the precision requirement of the scene aided navigation for the lunar orbiter very well.