Enhanced Image Processing for the CASPEX Cameras Onboard the Rashid-1 Rover

• Published in: Space science reviews 2024-08, Vol.220 (5), p.60, Article 60
• Main Authors: Théret, Nicolas, Cucchetti, Edoardo, Robert, Emilie, Virmontois, Cédric, Millancourt, Charles, Douaglin, Quentin, Amsili, Alice, Belloir, Jean-Marc, Amilineni, Santosh, Khoory, Mohammed, Ioannou, Zacharias, Lalucaa, Valerian, Lucas, Sylvain, Yana, Charles
• Format: Article
• Language: English
• Subjects: Aerospace Technology and Astronautics; Astronomical instruments; Astrophysics; Astrophysics and Astroparticles; Cameras; Color; Colorimetry; Dark current; Earth and Planetary Astrophysics; Geologists; Image enhancement; Image filters; Image processing; Image quality; Image reconstruction; Lunar geology; Lunar landing; Lunar surface; Lunar surface vehicles; Natural satellites; Parameter sensitivity; Physics; Physics and Astronomy; Planetology; Regolith; Roving vehicles; Sciences of the Universe; Space Exploration and Astronautics; Space missions; Space Sciences (including Extraterrestrial Physics; Spectral sensitivity
• ISSN: 0038-6308; 1572-9672
• DOI: 10.1007/s11214-024-01091-0

The Rashid-1 rover, being the main component of the Emirates Lunar Mission (ELM) developed by the Mohammed Bin Rashid Space Center (MBRSC), was launched in late 2022 on-board the Hakuto lunar lander. The scientific objectives of the rover were to investigate the regolith formations of our natural satellite and analyze the geology of its landing area. To perform its investigations, Rashid-1 carried two wide-angle cameras (CAM-1 and CAM-2) and a narrow-angle microscope camera (CAM-M) equipped with Bayer color filter arrays. The mission was however unsuccessful due to a lander failure during lunar descent which caused the loss of the payload. Despite this drawback, significant insights into exploration rover imaging have been gained through the extensive work done prior to launch to achieve the highest image quality from the on-board cameras, and the resulting CASPIP software package will be used for upcoming rover missions. This paper presents the CAM-1 and CAM-2 instruments and the planned advanced image products. In the first part, we provide a detailed presentation of the calibration of the instruments including their optical parameters, characterization of the detector in term of flat-field, optical ghosts, dark current, spectral sensitivities and distortion. The second part of the paper deals with colorimetry, focusing on the colorimetric characterization of the instrument as well as a description of the correction applied to obtain images expressed in the standard color space CIE XYZ and displayed properly in sRGB. Finally, the third part describes advanced image products developed to assist experts (geologists, navigation engineers). It includes a tool for distance visualization directly inside an image, and the creation of 3D images through stereoscopic reconstruction.