AMPLIFY VOL. 37, NO. 2
3D printing technology, also called “additive manufacturing,” is designed to create physical objects from digital models by depositing layers of material (e.g., polymer resins, plastic, rubber, metal) on top of each other. Advancements in 3D printing have made it possible to rapidly manufacture parts and equipment for spacecraft and space infrastructure, helping to reduce spacecraft R&D and manufacturing costs on Earth.
Efforts are underway to advance 3D printing to support in-space manufacturing, a capability that will become increasingly important for the future of space travel because it will (1) reduce the need for costly, resource-intensive resupply missions to space stations and other off-world bases and (2) lead to the establishment of space-based manufacturing platforms (in-orbit, on the Moon, and on planets like Mars).
3D printing is also important to space exploration because of its ability to support reusability and sustainability efforts. This article examines the various uses of 3D printing in the space industry and its role in the future exploration of the cosmos, especially for long-duration missions.
3D Printing on Earth
Currently, the biggest use of 3D printing in the space industry is Earth-based manufacturing of spacecraft parts. The benefits from 3D printing include accelerated development (from prototype to manufactured component), reduced weight and part count, reduced complexity of parts, and lower development and manufacturing costs. National space agencies and commercial enterprises are using the technology in a range of applications.
For example, SpaceX uses 3D printing to produce parts for its Falcon 9, Dragon, and Starship spacecraft. This includes engine chambers, injectors, nozzles, heat shields (for rocket boosters), and various spacecraft docking and cargo components.
Blue Origin pioneered the use of 3D printing in the space industry and uses the technology to manufacture engines and other parts for its New Shepard and New Glenn rockets. Blue Origin reportedly used 3D printing to speed the design of its BE-4 rocket engine, which uses liquefied natural gas. This allowed the company to replace parts that previously took a year or more to manufacture with 3D-printed parts that took only a few months to make.1
The European Space Agency (ESA) has used 3D printing to manufacture pure copper electromagnetic coils, which are important for electric motors and space operations, including satellite attitude control. The coils, produced using laser powder bed fusion 3D printing technology, demonstrate that this technology can support complex designs while increasing production efficiency.2
Some companies, including Relativity Space, seek to manufacture entire rockets and spacecraft using 3D printing. The company reportedly operates the world’s largest 3D metal printer, which allows it to manufacture rockets faster and with fewer parts than other processes. For example, Relativity’s Terran R is a medium-to-heavy lift rocket designed for rapid development and reusability. Current versions are built with aluminum alloys using a hybrid manufacturing approach. Eventually, the company hopes to build most of the rocket using 3D printing and is actively working to develop the necessary technology.
NASA engineers and academic researchers are 3D printing electronic components and circuits for space applications. An experiment conducted in April 2023 tested printed electronic circuits that were launched on a rocket that reached the edge of space.3 The test involved humidity and electronic sensors that were 3D printed directly onto two attached panels and the payload door of the rocket, with the sensors transmitting data to ground control during the flight.
Printing sensors directly where required allows more efficient utilization of available surfaces within a spacecraft.4 NASA is interested in advancing the technology to support 3D printing of electronics circuits and components in zero-gravity environments.
3D Printing in Space
3D printing in space is an experimental technology that holds vast potential for revolutionizing space exploration by enabling astronauts to manufacture spare parts, tools, key components, and building materials on demand. It is also of significant interest to companies looking to establish in-space manufacturing facilities that could take advantage of the zero-gravity and vacuum environment of space for researching and manufacturing goods that cannot be manufactured on Earth.
3D Printing Plastic in Space
NASA has been experimenting with 3D printing on the International Space Station (ISS) since 2014, collaborating with other space agencies, universities, and private companies like Redwire. This includes printing tools such as wrenches and ratchets and spacecraft parts like radiation shields. In these applications, the 3D printer (developed by Made In Space) is about the size of a desktop printer. It uses a fused filament fabrication process that feeds a continuous thread of plastic through a heated extruder onto a tray layer by layer to create a three-dimensional object.5
This and subsequent experiments were deemed successful because they indicated that microgravity had no significant engineering effect on the process, demonstrating that a 3D printer can function in space. This opens up the possibility that in-space 3D printing could not only help with the logistics of resupplying space stations in low Earth orbit (LEO), it could also prove useful for supporting long-distance space missions and the establishment of a permanent presence on the Moon and Mars.6 Tests of various 3D printing techniques are continuing on the ISS.
3D Printing Metal in Space
In February 2024, ESA delivered equipment to the ISS to test the feasibility of 3D printing small metal parts in space.7 The goals of this project are to:
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Understand how a metal 3D printer behaves in zero gravity.
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Determine which types of metal shapes can be printed in space and their qualities.
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Study how 3D metal printing in space may differ from printing metal parts on Earth.
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Ascertain how crew members can work safely and efficiently with 3D metal printers within the confines of a spacecraft.
From a technical perspective, findings from this experiment could provide a better understanding of the functionality, performance, and operations of metal 3D printing in space. They could also assist with benchmarking the quality, strength, and characteristics of 3D-printed metal parts.
From a strategic perspective, 3D metal printing could prove essential when it comes to the feasibility of long-duration human missions, especially on the Moon and distant planets. In addition to reducing launch-load weights, 3D printers could be used to manufacture metal parts necessary for maintaining equipment and key components on demand, including improvising custom tools for emergencies and other unforeseen situations. This is important because it would be impossible to predict every tool or spare part needed for a Mars mission or constructing a base on the Moon.
Recycling in Space with 3D Printing
3D printing is playing an important role in developing recycling capabilities that could make long-duration space missions more sustainable. In 2018, NASA installed integrated 3D printer and recycling hardware developed by Tethers Unlimited on the ISS.
In various experiments conducted in 2019, the ReFabricator demonstrated the ability to convert plastic waste (including from previously 3D-printed plastic parts) into 3D printer feedstock that was successfully used to create new tools and parts. The experiment included using plastic that had been recycled multiple times to create parts that were returned to Earth for testing.8
3D Printing in Space with Locally Sourced Materials
One of the most ambitious 3D printing projects involves using the technology in concert with locally sourced materials (i.e., in-situ resource utilization) to create the infrastructure necessary to support planetary exploration. Developing such technology could prove essential: in theory, it could reduce the need to transport pre-built objects from Earth to the Moon or planets, making space exploration and long-term settlements more practical and sustainable.
NASA has been collaborating with ESA, various commercial enterprises, universities, and other organizations to explore the potential of using 3D printing in this capacity. Key to the effort is the development of 3D printing technology that uses lunar regolith as feedstock to print blocks (and other shapes) that can be used to construct bases on the Moon and Mars. (Regolith is the dust and crushed rock found on the surfaces of terrestrial planets, moons, and some asteroids. The term comes from the Greek words for “blanket” and “rock.”)
3D Printing with Regolith
A number of projects and experiments have been conducted or are underway that combine 3D printing with regolith feedstock for space construction. The goal is to efficiently produce building materials that can be easily formed into structures able to withstand the harsh environments of space and extraterrestrial environments.
Project Moonrise
In 2021, scientists at the Technical University of Braunschweig, Germany, and Laser Zenntrum successfully 3D printed structures using lunar regolith simulant under zero-gravity conditions. Lunar regolith simulant is a synthetic feedstock composed of metal oxides and a binder that is designed to simulate lunar regolith. The project’s goal was to reduce the cost of launching payloads into LEO.
Researchers mounted a customized laser onto a lunar rover specifically designed to facilitate 3D printing in space. By manipulating the rover’s robotic arm, they were able to direct the laser to melt the lunar regolith simulant into precisely fabricated spherical shapes.9
These experiments were conducted on Earth using a large-scale research device called the Einstein-Elevator, a drop tower that allows experiments to be carried out under conditions of microgravity and a high repetition rate.10 The laser, which weighs less than 3 kg, demonstrated its resilience in space-like conditions.
Project Olympus
This ambitious project seeks to revolutionize space-based construction systems and is a key project for NASA’s upcoming Artemis mission, which aims to return humans to the Moon. Olympus focuses on creating robust structures for the Moon that will provide better thermal, radiation, and micrometeorite protection than traditional metal or inflatable habitats. Icon, a Texas-based company, is leading the R&D efforts. This includes developing a full-scale prototype off-world 3D printer that can use lunar and Martian resources as building materials. Icon is also developing technology for conducting 3D printing construction robotically on the lunar surface.
Icon plans to develop its 3D printing technology using both lunar regolith simulants and regolith samples brought back from Apollo missions to determine their mechanical behavior in simulated lunar gravity. Findings from these experiments should provide crucial knowledge and expertise for developing future lunar construction approaches for the broader space community, including critical infrastructure like landing pads, blast shields, and roads.
In 2022, NASA awarded Icon a US $57.2 million contract that runs through 2028.11 It is meant to further Icon’s commercial activities and other work it has collaborated on with NASA, including a 3D-printed, 1,700-square-foot simulated Martian habitat called Mars Dune Alpha, which NASA plans to use to conduct a series of analog missions simulating year-long stays on the surface of Mars.12
3D Microwave Printer
In July 2023, NASA awarded Redwire Corporation $12.9 million to prototype 3D printing technology. Redwire has developed a 3D printer that employs a microwave emitter to heat and solidify regolith simulant into materials to construct landing pads, roads, foundations, and other infrastructure.13 The project calls for making the technology scalable enough to meet various deployment needs, including on lunar rovers, vehicles, and robotic arms.
Bioprinting in Space
Bioprinting is a revolutionary technology that employs 3D-printing-like techniques to combine cells, growth factors, and biomaterials into biomedical parts that closely mimic natural tissue. Although experimental, bioprinting is being used to create mini tissues and organs for studying diseases and pharmaceutical side effects. The technology is anticipated to advance to the point where it can create replacement tissues and organs from a patient’s own cells.
Space agencies like NASA, biotech companies, and pharmaceutical firms are keenly interested in performing bioprinting in space because bioprinted materials in zero-gravity environments tend to retain their form and remain in a three-dimensional shape. This quality helps eliminate or reduce the need to use “scaffolds” and other supports typically required for bioprinting on Earth.14 In space, tissues can grow in three dimensions without support, simplifying the fabrication process.15
In future space missions, bioprinting could make it possible to print food and medicine on demand, reducing payloads while providing resources for maintaining crew member health. In-space bioprinting could also aid in the development of new drugs and therapies and support breakthroughs in regenerative medicine and organ transplantation.16
Several 3D bioprinting experiments have been conducted on the ISS. In 2018, the Russian state space agency delivered a magnetic printer called Organ.Aut, which was developed by 3D Bioprinting Solutions to culture cartilage cells using magnetic fields.17,18 Experiments conducted from 2018 through 2020 demonstrated this approach could create tissue constructs, helping to inspire additional research on producing artificial organs.
In July 2023, Redwire successfully bioprinted the first human knee meniscus in orbit (on the ISS). The meniscus was successfully returned to Earth for analysis. This project sets the stage for advanced treatments for patients with meniscal injuries on Earth and for crew members who experience musculoskeletal injuries on space missions. This is critical, since microgravity can cause cartilage degeneration that could affect the health and performance of astronauts on long-duration space missions and in lower-gravity environments like the Moon and Mars.
Sometime this year, Redwire is scheduled to experiment with bioprinting cardiac tissue on the ISS. This and subsequent experiments could lead to the ability to print complex, thick tissues that cannot be produced on Earth and the development of patches to be applied to the outside of damaged hearts.
Conclusion & Future Developments
3D printing has made a significant impact on the space industry by enabling on-demand manufacturing of spacecraft components and equipment within Earth-based facilities.
Use of 3D printing is destined to grow significantly over the next decade as space exploration becomes increasingly commercialized. As the technology evolves to meet commercial demands, it should become possible to print more complex parts and equipment, including entire (or nearly so) spacecraft, using robust, lightweight, heat-resistant materials (e.g., high-entropy alloys, nanocarbon-reinforced composites, and non-oxide ceramics) developed through advances in materials science.
3D printing to recycle waste and print electronic circuits and components will also advance the technology and lead to increased use. Moreover, the integration of 3D printing technology with generative AI will enable engineers (and, eventually, astronauts) to rapidly design and print parts and equipment on Earth and in space.
It’s quite possible that 3D printing’s biggest impact on the space industry will come from its use of in-space manufacturing. By reducing reliance on costly resupply missions, 3D printing will pave the way for the sustainable exploration of space and extraterrestrial environments.
Establishment of commercial space-based orbiting platforms using 3D printing techniques (including bioprinting) could also prove valuable. This would enable companies in industries like manufacturing, biotech, and pharmaceuticals to establish orbiting manufacturing facilities that leverage the benefits of zero-gravity environments for researching and manufacturing new products that would be complicated or impossible to develop on Earth.
Finally, the advancement of 3D printing technology capable of supporting in-situ resource utilization is crucial for the future of space exploration. By using locally available materials to build 3D-printed infrastructure, this technology can significantly reduce the expense of transporting construction materials from Earth to space. Eventually, it could enable on-demand construction on the Moon’s surface and Mars (a key goal of NASA’s Artemis mission). This will support both human and robotic missions and lay the foundation for a sustainable human presence in the cosmos.
References
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2 “ESA Advances Spaceflight with 3D Printed Copper Coils.” 3DPrinting.com, 3 November 2023.
3 Hille, Karl B. “Goddard, Wallops Engineers Test Printed Electronics in Space.” NASA, 25 July 2023.
4 “NASA Is Working on Technology to 3D Print Circuits in Space.” Universe Today, accessed February 2024.
5 Hurley, Billy. “3D Printing and Space Exploration: How NASA Will Use Additive Manufacturing.” Tech Briefs, 17 January 2020.
6 “Solving the Challenges of Long Duration Space Flight with 3D Printing.” NASA, 16 December 2019.
7 Garcia, Mark A. “Overview for NASA’s Northrop Grumman 20th Commercial Resupply Mission.” NASA, 25 January 2024.
8 “Combination 3D Printer Will Recycle Plastic in Space.” NASA, 19 November 2018.
9 Gislam, Steven. “‘Moonrise’ 3D Prints Lunar Regolith Structures in Zero Gravity.” Industry Europe, 14 January 2021.
10 “Einstein-Elevator.” Hannover Institute of Technology, accessed February 2024.
11 Ridgeway, Beth. “NASA, ICON Advance Lunar Construction Technology for Moon Missions.” NASA, 29 November 2022.
12 “Crew Health and Performance Exploration Analog.” NASA, accessed February 2024.
13 “Redwire Selected for $12.9 Million NASA Award to Develop Trailblazing Systems to Build Landing Pads, Roads, and Other Forms of Infrastructure on the Moon.” Press release, Redwire, 25 July 2023.
14 “3D Bioprinting.” NASA, 20 December 2023.
15 Cubo-Mateo, Nieves, and Michael Gelinsky. “Wound and Skin Healing in Space: The 3D Bioprinting Perspective.” Frontiers, 25 October 2021.
16 NASA (see 14).
17 “3D Bioprinting Solutions.” 3dbio, accessed February 2024.
18 “Building a Better Future in Orbit.” NASA, 21 July 2022.
