Constructing the first lunar base with space-ready 3D concrete printers

Humans first stepped on the Moon in July 1969. The iconic Apollo 11 mission was given a range of tasks to complete including the deployment of a television camera to transmit signals to Earth; the initiation of a solar wind composition experiment and a seismic experiment package as well as a Laser Ranging Retroreflector. During their exploration, Aldrin and Armstrong also gathered samples of the lunar surface which was used to glean important information about the geological composition of the moon.

The first Moon landing remains one of the most awe-inspiring moments in the history of humanity. However, despite their impact, crewed missions to the Moon only lasted until 1972. Research into the Earth’s closest satellite has continued despite no human presence on the Moon itself. Recent projects have included the Chinese National Space Administration’s (CNSA) mission, Chang 5, which successfully collected and returned approximately 2 kg sample of lunar regolith.

Artemis is an ongoing space mission run by NASA to land the first female astronaut and next male astronaut on the Moon's South Pole by 2024. It is the first crewed Moon mission since Apollo 17 in 1972.

Lunar base central to global interests in lunar exploration

As part of the Artemis mission, NASA conducted a Global Exploration Strategy survey, from which six lunar exploration themes emerged: These include:

• Human Civilization - Extend human presence to the Moon to enable eventual settlement.
• Scientific Knowledge - Pursue scientific activities that address fundamental questions about the history of Earth, the solar system, and the universe.
• Exploration Preparation - Test technologies, systems, flight operations, and exploration techniques to reduce the risks and increase the productivity of future missions to Mars and beyond.
• Global Partnerships - Provide a challenging, shared, and peaceful activity that unites nations in pursuit of common objectives.
• Economic Expansion and Public Engagement.

Central to many of these themes is the need for a more permanent base on the Moon. Shelter on the lunar surface would provide the laboratories, storage, and human habitation needed to fulfil the wider lunar-related mission goals. A leading construction idea for such a base is 3D printing using available lunar resources.

The Artemis program will see Astronauts back on the Moon by 2024. Image via NASA

Building-scale 3D printing

While 3D printing started small, using non-structural plastics, it has evolved to a wide spectrum of materials and expanded to massive scales. Of note is 3D printing using concrete-type materials that can maintain its shape when wet, rapidly harden after pouring and have the required strength for habitation. This technology has huge potential for lunar construction.

A 3D printed building starts with a digital 3D model of the structure, then just as with any other 3D printed object, this model is virtually sliced horizontally into multiple layers. These layers are converted to paths to provide the 3D printer with a guideline about which direction to move when depositing the material. The 3D printer then deposits the printing material layer by layer, building the complete structure one step at a time.

Luyten demonstrates robust lunar 3D printing concept

Space exploration has become increasingly democratized. With startups and smaller companies now leading the way in the next generation of space-related technology. Among these are the Australian 3D printing construction company, Luyten. Luyten recently launched its intent to provide lunar construction systems as part of a new concept called Project Meeka. Luyten says they took on the challenge of designing a lunar base concept after developing their own 3D printing system for buildings on earth and realizing the enormous potential their technology could have for lunar exploration. “To date, humans have not been able to settle on the Moon or transport materials capable of constructing some type of lunar settlement until now. At Luyten, we have created a 3D printer light enough to be space worthy, so it can be transported to the Moon at a reasonable cost and used to build a lunar settlement using lunar materials," Luyten's CEO, Ahmed Mahil explains.

Central to Project Meeka is the creation of building material from lunar regolith. Luyten proposes that once a mission lands on the Moon, a fleet of rovers equipped with ground-penetrating radars would scatter over previously identified potential building sites. Once they have confirmed the areas have the required strength and stability, excavators will collect lunar regolith from the surface and deposit it on a reservoir. From here, the material is separated by size and material composition. This sorting is essential as only the ultrafine particles are suitable for creating the building material. The finest regolith is then sintered into printable materials using concentrated microwaves.

The Meeka concept with lunar base and printer. Source: Luyten

To test the concept Luyten has completed test prints using simulated lunar regolith. The material, high in silicates, is based on the material profile of previously collected lunar regolith samples. The test was a successful first step with more testing planned to continue to develop novel ways to bind the material into a printable form.

Foldable large scale 3D printer

The concept uses a modified version of the company’s propriety building scale 3D printer. Dubbed Platypus Galacticas, the printer can be folded into a small, light payload 3m by 4m. It can then be unfolded once on the Moon to its building envelope size of 9m by 12m. “We have designed the printer for compactness using lightweight composites for the printer’s structure and robotic transforming technology, making it ideal for space transportation purposes,” Mahil said.

Luyten’s architectural designer Brandon Nelson explains that Project Meeka’s habitats are designed using high-strength cylindrical shapes. The rounded profile of the building has been tested through a battery of simulations to ensure it has the required physical properties to withstand the extreme environmental conditions of the Moon.

“3D printing construction is going to be the next wave of architecture throughout the world which is going to further architects having more control of projects and how buildings are actually made. 3D printing is going to lead to a whole new architecture model that gives architects a more hands-on design/ build approach to architecture,” Nelson said.

The company is actively looking for partnerships to take Project Meeka to the next stage of development.

Conclusion

3D printing will likely play a significant role in the construction of future lunar bases. Luyten’s Meeka Project addresses two of the most important challenges for lunar construction; materials and lightweight building tools. This concept again strengthens the growing trend that startups are disrupting the space exploration industry.

References and further reading

[1] Hubbard, Scott (2016). What Do We Do with the Moon?. New Space, 4(1), 1–1. doi:10.1089/space.2015.29003.gsh

[2] Space: Investing in the final frontier [Internet], Morgan Stanley, Retrieved October 2021, Available from: https://www.morganstanley.com/ideas/investing-in-space

[2] Carr, Belinda, "Introduction to 3D printed concrete" [Internet], YouTube, 8 July 2018, https://www.youtube.com/watch?v=-Csy2e1B2v0.

[3] Peacock DA. Mining on the Moon. Min Eng. 2017;2017:23-31