Towards a Semi-Autonomous Robotic Exploration of a Lunar Skylight Cavity

This study evaluates the feasibility of a robotic exploration mission to a skylight located in the Marius Hills region on Moon. The study is based on theoretical evaluations while making use of existing results from previous and currently running projects. Parts of the approach were already evaluated by autonomously navigating and mapping in a lava tube and other field trials in analogue environments. We address a solution to access and map a lunar lava tube with a semi-autonomous heterogenous team of exploration rovers. Main systems are: 1) a surface rover, which serves as anchoring point, communication relay and power generator, 2) a highly mobile exploration micro rover foreseen to rappel down into the skylight for tube exploration and 3) a tether management and docking system which can be attached to the exploration rover to safely lower it into the lava tube and serve as power and communication hub during cave exploration. For descending we propose a rappelling approach using tethering and actively controlled hybrid legged-wheels on the exploration rover. The rover uses path planning to avoid obstacles on its way down the vertical surface. When the bottom of the skylight is reached, the tether spool is deployed as docking station. After successful deployment, different autonomy levels are possible -from remote-controlled to fully autonomous- to explore the unknown environment.