Abstract: The field of autonomous navigation for unmanned ground vehicles (UGVs) is in continuous growth and increasing levels of autonomy have been reached in the last few years. The task becomes, however, more challenging when the focus is the exploration of planet surfaces, such as Mars. In those situations, UGVs are forced to navigate through unstable and rugged terrains which, inevitably, open the vehicle to more hazards, accidents, and, in extreme cases, complete failure of the mission. This thesis tackles the problem of terrain traversability analysis in the context of planetary exploration rovers, delving particularly into Mars exploration. The aim of the research is the development of a hybrid architecture, which enables the assessment of terrain traversability based on the results of both an appearance-based approach and a geometry-based approach.