project09:2025Msc2JIP

Problem statement

After more than 50 years since the Apollo 17 mission left the moon, many space agencies are eyeing a returnof crewed missions to the lunar surface, and unlike the short visits in the past, plans are being made for permanent human settlement. Yet, transforming this vision into reality comes with unparalleled challenges.

The lunar environment is characterized by serious threats, ranging from frequent micrometeorite impacts, intense radiation levels (up to 2200 mSv/event during solar flares and CMEs [1]), extreme temperature fluctuations between day (420 K) and night (100 K) [2], and moonquakes, which can reach body wave magnitudes mb up to 5 during shallow (most energetic) events [3]. Many recent studies have consistently advocated forthe establishment of lunar outposts inside lunar lava tubes [4], [5], [6]. These large (100-300 m in diameter) cave-like natural, which are formed by ancient lava flows, could protect astronauts and structures from radiation [7], meteorite impacts, and the extreme temperature variations [8]. Some of these sub-surface tunnels are thought to be accessible by the superficial pit entrance [9], [10], and therefore are of great interest for future lunar settlements and for the following study.

A major challenge for lunar construction is the prohibitively high cost of transporting payloads, estimated at approximately $1 million per kilogram. In situ resource utilization (ISRU) offers an appealing potential solutionto this problem by leveraging lunar soil (regolith) as a primary building material, reducing dependence on costly Earth-supplied resources, which is essential for making the construction of the first lunar habitat both economically viable and sustainable. The high transportation costs also render delivering heavy construction equipment, such as cranes or excavators, to the moon impractical. Furthermore, given that the construction of a lunar habitat is likely to require an extended period, relying on human labor is infeasible. Human involvement would necessitate temporary shelters and expose crews to severe life-threatening risks. Consequently, we envision the possibility to deploy robotic swarms and additive manufacturing systems ahead of human arrival. These autonomous systems could collect lunar soil and construct a fully functional habitat, ensuring that the environment is safe and ready for incoming astronauts.

Within the ISRU context, Additive Manufacturing (AM) technology [11] is receiving increasing attention due to its potential to produce various geometrically complex building blocks and structures in extreme environments. Sintering, particularly through Selective Laser, Solar, or Microwave techniques, is a promising solution under investigation for its ability to fuse regolith into structural geometries without additives (unlike concrete-like 3D printing), offering material-efficient methods for lunar construction. Up to date, various experiments have successfully sintered and formed parts [12], [13], rendering this fabrication method appealing for extraterrestrial construction.

While many concepts for lunar habitats have already been developed and proposed [14], [15], [16], these often fail to address many of the core challenges inherent to lunar construction. Some concepts rely heavily on the costly transport of large construction equipment/robots and additives from Earth (Chinese Super Mansion [17] and Project Olympus [18]), while others rely on the use of heavy ready-to-live modules [19]. Therefore, the primary objective of this project is to develop and outline an autonomous robotic construction process to enable practical and scalable lunar construction of a lunar habitat within a lava tube using In-Situ Resource Utilization (ISRU) methods.

Sub-objectives include

• Outline the construction process from gathering and processing lunar material to the creation of construction geometries using Selective Laser Sintering
• Defining requirements for several aspects of the robots used in the construction process, including coordination strategies, traversal mechanisms, required tools and support systems such as charging infrastructure.
• Characterizing an ideal lunar regolith composition for construction and outlining how to acquire this material, from gathering the material to processing/filtering the material.