Calibration and 3D measurement from Martian terrain images

An on-Mars calibration procedure of a planetary lander vision system is presented. It is based on developments in computer vision. The calibration is retrieved from the images of the Mars terrain. The procedure is based on the relations between multiple views of the same scene. It allows us to retrieve the calibration on Mars without any additional requirements on the system. Once the system has been calibrated, the same images can be used to estimate a digital elevation map (DEM) of the environment around the lander. The images are first processed pairwise using a stereo algorithm yielding sub-pixel disparity maps. An algorithm was developed to efficiently extract a DEM from the disparity maps. The DEM can be generated at any desired resolution (interpolating if necessary) and occlusions are easily taken into account.