Alison Lewis of Made in Space, during a test flight in June, via the company's site
3D printing is old news. We know these printers exist and that they can create anything from amorphous blobs to machine guns by layering any variety of materials following a computer-dictated plan. The benefits in space are obvious, even if you've never seen Spock's Replicator. Crews could print tools, spare parts, and, eventually, whole habitats on other bodies from material found on the Moon or in asteroids. We could stop sending up so many Russian supply rockets, and we'd never have to worry about crews creating an Apollo 13-esque fix for a problem using a page from a manual, a plastic bag, and a sock.
We also know that space is getting "disrupted" by Elon Musk, Richard Branson, and a host of private companies that are slowly filling in vacant buildings at Cape Canaveral.
Over in California, a startup called Made in Space is making small steps into the 3D printing in space frontier. Founded in 2010 by designers and engineers who met at Singularity University, the company has spent the last three years working on a system that can print in microgravity. And pending one last test by NASA, that's precisely where it's going next: a ship carrying one of its printers is set to arrive at Space Station next year.
Made in Space's 3D printer, small enough to launch to the ISS. via
On Earth, where gravity keeps things in place, 3D printing works pretty well. Hot molten plastic is squeezed out of a nozzle like toothpaste out of a tube. It settles and cools, making it possible for layers to pile up creating a three dimensional object. The whole process is guided by a computer, which following a predetermined design. But microgravity—there’s still a tiny amount of gravity affecting orbiting spacecraft so astronauts aren’t properly in a zero gravity environment—makes the whole business much harder.
Thermal properties are different in space; keeping things appropriately hot and cold involves a lot more work. There’s also the matter of keeping things in place. Things tend to float around in space, and 3D printers have plenty of moving parts that are likely to float like cogs and belts that make the machine work. If these vital pieces move, even by a fraction of a millimeter. it could ruin a print. 3D printing in space demands a delicate balance between letting things move when they need to move and keeping them rigid when it’s imperative they stay in place.
Made in Space has found a way to make it work. In June, they proved their printer works by passing a critical milestone: successfully printing in the microgravity of a zero-G parabolic airplane flight.
The team took a printer into one of NASA's "vomit comets," a hollowed out 727 jet built to fly in parabolic arcs to create brief bouts of weightlessness. And during those bouts the printer printed. It also worked in lunar gravity (one-sixth Earth’s) and even Mars gravity (one-third Earth’s) environments.
In a separate set of recent tests, NASA proved that two rocket engine injectors made with a 3D printer performed as well as traditionally constructed parts. They did this, of course, by blasting these parts with "hot fire": temperatures approaching 6,000 degrees Fahrenheit (3,316 degrees Celsius) and extreme pressures, The team that printed them, at the Marshall Space Flight Center in Huntsville, Ala., found that after 11 hot-fire tests, or 46 seconds of total burn time, the parts did as well as traditional parts. Those parts, to be used in the SLS rockets designed for carrying astronauts to Mars, cost $10,000 each and took six months to build. The 3D-printed versions, by contrast, cost less than $5,000 and, after a 40-hour print job and finishes, reached the test stand in a matter of weeks. This is what the most recent test looked like:
"At NASA, we recognize ground-based and in-space additive manufacturing offer the potential for new mission opportunities, whether printing rocket parts, tools or entire spacecraft," Chris Singer, director of Marshall's engineering directorate, said in a statement. "Additive manufacturing will improve affordability from design-and-development to flight-and-operations, enabling every aspect of sustainable, long-term human space exploration."
The Made in Space unit, which is about the size of a shoebox and made of metal with a viewing window, will give astronauts some independence from the Earth. Its designers say their printer will be able to print spare parts ranging from practical toilet pipes to tools that could fix a fatal problem and save a mission in distress.
The version that will fly to the ISS next year will likely be able to print about 30 percent of the parts astronauts typically need on the station. No word if this model will eventually be able to 3D print pizzas.
Additional reporting by Alex Pasternack.