The Design of Autonomous Robotic Technologies for Lunar Launch and Landing Pad (LLP) Preparation

The next major milestones in the Artemis Program will be designing and developing lunar bases to establish a permanent human presence on the Moon. A critical first step in base development will be detailed surveying and site preparation required for building launch and landing pads. Given the lack of infrastructure, including GPS and continuous high-speed data connection with Earth, any system to perform initial base prepa-ration needs to be self-reliant. In addition, the lunar surface environment poses several significant challenges to developing a base compared to a terrestrial environment. For example, the lunar regolith contains fine sand with the properties of crushed glass and is very abrasive. Furthermore, the lunar surface undergoes extreme temperature swings between lunar day and lu-nar night; in addition, the surface is exposed to solar and cosmic radiation and bombarded with micro-meteorite particles from time to time. These factors make a compelling case for the use of autonomous robotics systems that rely on limited communication from Earth or orbiting assets to perform the dull, dirty, and dangerous tasks of lunar base preparation. We are developing an autonomous robotic solution to survey and preparing durable launch and landing pads using in-situ resources. Our baseline solution will utilize a team of robots docked together to form a chain. This robot team will perform close coordination sweeps to cut, clear, level, backfill and create regolith berms surrounding the circular landing pad. A robot team forming this chain has some distinct advantages. It can perform sweeps without leaving gaps, enabling near-optimal area coverage trajectories to minimize operating time and energy consumed. The robot team working in a chain can also utilize collective pushing or pulling capability to move loads otherwise impossible when one robot operates alone. Critically important, close coordination between robots can enable precise, comparative leveling without relying on external geo-positioning infrastructure. Forming a chain of these robots enables extensibility, with more robots increasing concurrent coverage. The potential for this tech-nology exists not just for planetary robots but also spacecraft performing area coverage or volume coverage tasks. In addition, the system can also handle the loss of individual robots in the chain by having the remaining robots forming a chain to pull the unresponsive rover out of the way or provide assistance to stuck rover. Utilizing this chaining strategy, the robots can perform relative localization, site leveling, boundary outlining, and berm formation. Apart from clearing, leveling, backfilling, and forming berms, the robots will also need to compact and rigidize the launch and landing pad to minimize disintegration. Our previous research in this area led to the solar sintering of sand to form a hardened top layer.