AI Spacefactory has created a vision that looks plausible and comfortable if you stay inside.
NASA has been running a 3D Printed Habitat Challenge to develop “digital representations of the physical and functional characteristics of a house on Mars.” Like so many competitions we look at here on TreeHugger, the top prize is not our favourite. Running a very close second (winning $20,957.24, or 71 cents less prize money than the winner, based on points) was the AI. SpaceFactory, which proposed MARSHA.
The spectacular video explains why the designers chose the cylindrical form; it encloses more useful space than a dome, and the arm of the 3D printer doesn’t have to stretch very far.
Apart from being highly effective pressure vessels, they provide the greatest ratios of usable floor area to surface area and usable floor area to volume and diameter. Reducing surface area means using less material under less stress, reducing volume means reducing energy loads on mechanical systems and reducing diameter directly reduces structural stresses, especially at the base, where uplift forces will require anchorage into uncertain ground. Unlike domes they do not produce unusable overhead volume or unusable perimeter floor area.
There is serious engineering here by Thornton Tomasetti, known for their super-tall buildings; Engineer Dennis Poon is seen here with the author in a ThyssenKrupp elevator mockup.
Jeffrey Montes and his team at AI. SpaceFactory have created an interesting material to build the towers; the dome is printed out of a mix of locally mined basalt and renewable bioplastic (polylactic acid, or PLA) processed from plants grown on Mars. PLA is made from corn starch, cassava roots or sugar cane; they don’t say how many acres of crops have to be grown to generate enough PLA to squirt out a cylinder, but that sounds like a challenge all on its own.
PLA has countless applications as an expendable material through the full mission timeline. Being a bioplastic, it has the added benefit of dual modes of in-situ manufacture: via the fermentation of carbohydrates by bacteria or via chemo-catalysis. On Earth, most PLA is derived from polysaccharides produced by plants. The same could be carried out on a future Mars settlement, where inevitable plant and other biological waste provide an opportunity to close material/ metabolic loops.
However, growing your own materials on Mars makes a lot of sense when you do the math on shipping it there without Amazon Prime; it takes 90 pounds of fuel to get one pound of stuff to Mars. Growing it makes a lot more sense than shipping it.
AI Space Factory
The entire cylinder is clamped to a base that allows for thermal stresses and significant wind loads. Then the printer goes to work creating the double-shelled structure.
Marsha's layout is zoned with both of these principles in mind. At ground level, the “garage” is the interface with external systems and exploration activities with a supporting “wet lab”.
“Just above is 34 square meters of joint dry lab and kitchen acting as the main hub.” I am not sure that this is a good idea. When I helped out in the lab at the Ontario Science Centre years ago they told us never to keep our lunch in the same room as the lab; you don’t want to eat the wrong thing.
On the third level are the individual cabins, “sanitation pod” and hydroponic garden.
And at the top, the bright “skyroom” is dedicated to informal recreational uses and exercise. Each level has at least 1 window, which together cover the full 360°panorama. This is nice, because it is hard to tell the kids to go play outside.
Elon Musk has said, “I would like to die on Mars. Just not on impact.” I do not know how many people share that fascination, but I do know that the MARSHA project team has designed spaces where it would be nice to pass the time. It actually might not be a bad place to grow old in, given that you only weigh 38 percent as much, so climbing those big stairs will be a breeze.
Outside, there will be lots to do -- dusting the solar panels, maintaining the nuclear plants and growing the PLA producing plants. The thing that I love about this vision is that it actually seems plausible.