Touchdown Dynamics and the Probability of Terrain Related Failure of Planetary Landing Systems - A Contribution to the Landing Safety Assessment Process

Abstract

Landing safety assessment is an integral element of the planning of a landing mission. This thesis contributes to such assessment with the modelling and deduction of the functional limits of a legged landing system and its terrain-related failure probabilities. A mathematical method has been developed to determine these terrain-related failure probabilities. The lander's touchdown dynamics is represented by a high-fidelity numerical multibody simulation which is validated by experimental data from a dedicated test campaign. The analysis of the terrain-related failure probabilities remains incomplete without knowledge about the geotechnical properties of the landing site. This information is obtained from a landing site characterization. An analysis step extracts this information from high resolution digital terrain models under consideration of the specific baselength determined by the landing platform's footprint. A robotic lunar landing mission is used as application case study.