Mathematical analysis approach for the pre-design of landing platforms with alignment, levelling, and lowering function

Abstract The objectives for celestial body exploration especially regarding lunar exploration became more and more demanding over recent years. New landers are needed for missions in the Artemis programme by the National Aeronautics and Space Administration (NASA) or the Terra Novae exploration programme by the European Space Agency (ESA) that offer a great deal of reliability and versatility. A system that can level, align, and lower the whole landing platform could offer a lot of benefits in comparison to older lander concepts without such a system. Challenges like unevenness of the ground, slopes in the area of the landing site, as well as different compression of the lander legs can be counteracted. Additionally, access to the lander’s payload bay is simplified by lowering the landing platform as a whole closer to the ground. This study takes a closer look at an approach for the conceptual design of such a mechanism in the early design stages of a lander using a minimal number of known parameters and low computational expenditure. The approach of calculating the motion of the lander and the forces due to the motion on each of the legs primary strut interfaces is first explained and then demonstrated for the European Large Logistics Lander (EL3) on the basis of a mechanism, which moves the primary interface of each landing leg in the vertical axis of the lander.