If NASA’s Journey to Mars project succeeds, the astronauts who make the 140 million-mile (225 million-km) trip to the Red Planet in the 2030s will need someplace to stay. The space agency is looking at 3D printing, using on-site materials, to manufacture humanity’s first deep space home.
“Creating a self-sustaining civilization on Mars is one of mankind’s greatest endeavors,” said Melody Rees, design and project manager at Branch Technology Inc. (Chattanooga, TN), an architectural fabrication firm specializing in large-scale 3D printing. “We [must] develop sustainable construction technologies and intelligent design strategies early on.”
In August, Branch collaborated with architecture and design studio Foster + Partners (London) to win the final competition in the second phase of NASA’s 3D-Printed Habitat Challenge. The winners competed against four other teams for $250,000 top prize. The competition had three levels: The team placed third in Level 2 and first in Level 1.
Although the NASA challenge was the collaborators’ first project together, Branch’s decision to partner with Foster was an easy one because the studio uses the best material technologies and does things right, according to Rees, who led the winning team. “With that mentality, we really wanted to work with them,” Rees said.
The feeling is mutual. Marc Guberman, a Foster partner, said: “For the NASA 3D-Printed Habitat Challenge, a collaboration between Foster + Partners and Branch Technology was essential to develop innovative concepts on structural optimization, fabrication technology and material efficiency. The partnership was truly productive and collaborative.”
Possible future collaboration could include a commercial project or the third phase of the NASA competition, in 2018, to build a habitable structure. The first design phase of NASA’s challenge was completed in 2015.
For the August competition, teams printed specimens made of recyclables and materials like those on Mars, including three cylinders, three beams, and a dome, all in 22 hours.
The Branch team first had to design and build a printer that uses fused deposition modeling because structural components made with the company’s C-FAB process in its Chattanooga factory are open, cell-like matrices. The prefabricated pieces are shipped to a construction site, then filled with spray foam and coated with architectural material, something that would be a challenge to do on Mars.
“That was quite a lot of work, building a robot in just nine weeks,” said Rees, who added that the team had to deal with feed and print issues, too.
The team used a robotic arm from Kuka Robotics USA (Shelby Township, MI), installed in a trailer, for its portable printer. For pellets to print with, the team turned to materials design company Techmer PM (Clinton, TN).
NASA required that structures be made of 70% regolith and 30% recyclable material. Techmer designed a custom geopolymer, a blend of a basalt-based material (because basalt is similar to Mars’ surface) and recycled plastic. The resulting dome weighed 120 lb (54 kg) and withstood up to 3735 lb (1694 kg) pressure in crush testing.
Thinking they might have a better idea, the Branch team printed a second C-FAB structure that weighed 16 lb (7 kg), a fraction of the competition dome. “So again, coming back to the exorbitant cost of moving materials through space, we thought that C-FAB would be a better solution, and printed the same demonstration piece to show NASA that there are other ways to think about this problem,” Rees said. “And so, we hope to influence their thinking in the future.”
With the progress NASA is making, will we someday see Deep Space Airbnb?