Earth’s outer neighbor has long been rumored to be in NASA’s cross-hairs as a target location for creating human habitats with 3D printing. NASA recently provided some truthful substance to these rumors with last month’s revealing of the Ice Dome, a partially 3D printed Martian architecture concept. NASA has also enlisted the services of Behrokh Khoshnevis, a University of Southern California engineering professor, in their push to create a successful system for 3D printing housing on Mars using materials found on the planet. Many experts believe 3D printing is a viable tool for building Martian habitats once we finally reach the surface. The versatility, portability and effectiveness of 3D printers is the reason why these experts believe it can be an extremely useful resource.
The Ice Dome
While the Ice Dome and its antecedent, the Ice House, have sparked a lot of interest after receiving NASA’s stamp of approval, Professor Khoshnevis has a different opinion on how 3D printing should be used in the construction of Martian habitats. Firstly, he believes that the inflatable windows of the Ice Dome would surely fail due to their polymeric material. He provides, “Inflatables are made of polymeric material, like vinyl, so they won’t survive long because the radiation on Mars is pretty intense. Radiation is the enemy of polymers, causing it to become weak and fragile.” He believes that using regolith, the layer of unconsolidated rocky material covering the planet’s bedrock, instead of ice would provide a much better building material.
Khoshnevis, who has experimented with materials similar in shape and oxide percentages to regolith, explains, “I built some very primitive things, melting the materials to see if I could use the heat to change the sand into rock…I wanted to see if the stimulants could be melted and extruded, and if I could use them in my 3D printing idea.” According to Khoshnevis, these surface materials would provide the ideal material for 3D printing on Mars. The only challenge now is getting the 3D printer itself to Mars. Once this happens, the 3D printers would have to be programmed to automatically print and construct the structures. This automation is a crucial step, however, because the timely signal delays from Earth to Mars make it impossible to control the machinery from Earth.
A 3D printable habitat, designed by Behrokh Khoshnevis.
Previously, many space agencies were focused on setting up bases on the Moon. Although this focus has since shifted, Khoshnevis developed his own 3D printing technique for this called contour crafting to design 3D printable habitats that could potentially be used on the Moon. The habitats could not only provide emergency shelter in areas with little housing, but come at a relatively low-cost. According to Khoshnevis, “I believe building in space is going to become commonplace in less than 50 years. All we have to do is design self-replicating factories and build a lot of objects. In a short time, our capability to manufacture in space will be many times what we can do on Earth.”