MPE, THE GERMAN LUNAR MOBILE PAYLOAD ELEMENT

摘要

Europe is presently preparing for a robotic mission to the Earth's Moon. The mission under study called Lunar Lander is aiming for a Moon landing in the year 2018. The Lunar Lander is capable of a precise landing near the lunar south-pole and shall have a payload of approx. 40kg [1,2]. Late 2010, the German Space Agency, DLR, invited the German industry to submit a proposal for a study about a Mobile Payload Element (MPE) which, as a baseline, could be a German national contribution to the Lunar Lander ESA Mission. MPE is designed to be a small, autonomous, innovative vehicle of roughly 10-12 kg for scouting the environment in the vicinity of the lunar landing site. The novel capability of the MPE - thus far not matched by any other planetary rover but eventually required for e.g. future robotic Mars sample return missions - will be to acquire samples of lunar soil some distance away from the lander, and to bring them back to the spacecraft for analysis by on-board instruments. This will enable access to soils that are less contaminated by lander descent propulsion system plumes to increase the chances of detection of any indigenous lunar volatiles contained within the samples. Kayser-Threde, Germany, as the Phase 0/A industrial prime, has assembled relevant German industrial and institutional competences in space robotics for this study. The core study team led by Kayser-Threde consists of the companies von Hoerner & Sulger in Schwetzingen and Astrium in Bremen, and two institutes, the DLR Institute for Robotics & Mechatronics in the Greater Munich area and the German Institute for Artificial Intelligence, DFKI, in Bremen and is supported by the DLR Institute for Planetary Research, Berlin. The Phase 0/A study began in April 2011. In the first phase 0, a concept survey and trade-offs based on a reference scenario, which has been developed as part of the study. This resulted in a first baseline rover concept characterized by a four-wheel active chassis, a power supply with fixed solar generator, a secondary battery and a primary battery as backup, a thermal control system based on active heating and passive insulation, an optimized sensor and autonomy package as well as full redundant avionics. The system mass of this phase 0 concept was estimated with ~17kg. In a next step the concept was revised by reducing redundancies and discarding doubled components. For the Phase A work a MPE concept with a total mass of 12.7kg was proposed, owing the same functionality as the precursor concept. This revised baseline assumes limited redundancy, operation of the rover during the first mission phase without darkness and a payload consisting of a camera payload, a close-up imager and a "mole" as payload sampling device. With a moderately increased mass budget, more reliability and an improved payload can be realized.