Photogrammetric Processing of Tianwen-1 HiRIC Imagery for Precision Topographic Mapping on Mars

The High-Resolution Imaging Camera (HiRIC) onboard China’s Tianwen-1 Mars probe aims to acquire detailed imagery of the Martian surface comprehensively investigate its topography and geomorphology. HiRIC is a pushbroom camera comprising three CCDs simultaneously achieve sub-meter resolution large swath. However, processing images using conventional photogrammetric workflow difficult due shifts narrow overlapping among CCD lines. This paper presents novel approach for precision topographic mapping that incorporates 1) fitting initial Rational Polynomial Coefficients (RPCs) from position pointing data, 2) deep-learning-based method tie-point matching between adjacent cross-orbit images, 3) bundle adjustment multiple tripled-epipolar image generation ensure inner-orbit consistency, 4) block orbit 5) dense space intersection based on refined RPCs generate Digital Elevation Models (DEMs). Experimental analyses were conducted covering landing region Zhurong rover. results revealed subpixel accuracy was achieved residuals multiple-CCD or multiple-orbit images. Comparison with reference data (HiRISE MOLA DEMs) mean deviation less than 7 m in terms geometric subtle details DEM. presented offers reliable solution new dataset mapping.