In 1970, an oxygen tank explosion forced NASA to abort the Apollo 13 lunar mission. The crew spent four tense days fighting their way back to Earth despite limited power, a water shortage and heat loss.
During their return, the crew members were forced to pile into one part of the spacecraft: the lunar module. Carbon dioxide levels began to rise, as the module was only equipped to carry two people for 30 hours, not three people for four days. They needed more carbon dioxide filters.
The crew had plenty of spares from another part of the spacecraft, but they were square; the lunar module relied on circular filters. A NASA engineer and his team spent two days back on Earth racing to find a way to make the extra filters compatible. The final solution called for duct tape, a towel, a plastic bag and a flight manual — materials already on board the module that the astronauts could assemble themselves. It worked. The crew made it safely to Earth.
3D printing startup Made in Space wants to make jury-rigged space tools a thing of the past. Had its 3D printer — which NASA recently said is safe to use in space — been on board the lunar module, the crew could have designed and printed a part to connect the filter in just a few hours.
“There surely has been a lot of near misses in the past with spaceflight,” CTO Jason Dunn said. “When we start going out to Mars and back to the moon and going to asteroids, it’s going to be even more important that they have printers with them.”
Made in Space is developing a 3D printer that will be brought aboard the International Space Station in 2014. It will be the first 3D printer in space and capable of building spares for many of the station’s parts, plus tools and equipment upgrades. As a result, it will end many of the “game over” scenarios that the space industry spends so much time worrying over.
“The problem with space missions today is you only get one shot,” CEO Aaron Kemmer said. “If you send up a satellite or a spacecraft or a tool or pretty much anything and something goes wrong, you’re then out of luck.”
Developing the printer
Made in Space formed in 2010 with the theory that an off-the-shelf consumer 3D printer with a few modifications would work in space, Dunn said. The company tested several models, plus a few of its original designs, in 2011.
You test a 3D printer bound for space in a modified Boeing 727. The plane flies in parabolic arcs that create 20 second bouts of weightlessness — simulated microgravity. Made in Space flew 400 parabolas with its printers in 2011. The team soon found they all had one flaw or another that meant they did not work in low gravity.
“In zero gravity, thermal properties work a little differently. Convection doesn’t work the same when you don’t have gravity,” Dunn said. “There’s interesting tricks we came up with to make sure we’re keeping the hot things hot and the cold things cold. We learned a lot about how you can make a 3D printer work in zero gravity.”
Shortly after those first tests, NASA contacted Made in Space about building a printer for the ISS. The company spent 2012 designing the printer. By the end of the year, it had a rugged, reliable system that would be easy to use for a member of the crew.
The printer is a bit larger than a shoebox and, unlike most 3D printers, it is totally enclosed. Its outside is sturdy metal, plus a glass front that provides a view of the insides. A squat nozzle prints the layers of melted plastic. When an object is finished, it is pulled from the printer on a removable printing platform.
In June, the crew got back in the 727 to test their design. They measured the strength of its parts, printing resolution and how well extruded layers stuck together. Over 120 parabolas and four flights, they demonstrated that their printer is the first to function in microgravity. It could operate on the moon or Mars and under gravitational forces twice what is found on Earth.
“We designed a system that is essentially gravity independent,” Dunn said.
3D printers are built from lots of small parts, including belts and gears that are normally held in place by gravity. To be gravity independent, the printer’s parts had to be secure in three dimensions.
“Gravity was there whether the designer intended or not,” Dunn said. “With a 3D printer, if something floats by a fraction of a millimeter, that can completely ruin a print. You have to make sure things are allowed to move when they need to and very rigid when they need to be.”
The printer also has to be rugged enough to survive the launch into space, when it will be subjected to intense environmental factors like vibration. The final NASA flight qualification test two of the printers passed this month ensured that the final printer will be ready to face those challenges. It also verified the printer is safe to use aboard the ISS.
Now, the Made in Space team will move on to building its final printer, which will be shipped to the ISS aboard the SpaceX Falcon 9 rocket next year.
Improving repairs and science on the ISS
NASA is in the beginning stages of bringing 3D printing to several aspects of space travel. In May, the agency announced $125,000 in funding to research printing food in space. NASA and the European Space Agency have also raised the idea for a 3D printed moon base. But the science hasn’t arrived yet.
3D printing will have an immediate impact on the ISS. A NASA study found that 30 percent of the parts that have broken in the past likely could have been fixed by Made in Space’s printer. It can make nuts, bolts, springs and even piping for the ISS toilet. It can make a puzzle for a bored astronaut.
“There’s literally billions of dollars of spare parts that have to be on the station because they never know what they’ll need,” Dunn said. “There’s times when a tool is needed and the tool didn’t exist.”
A 3D printer will also improve research. Governments and private companies will be able to rapidly print and test many iterations of an object instead of pouring all their resources into building and shipping one. Kemmer said that shifts the industry’s mindset to one that resembles Silicon Valley. Innovation will happen faster and more prevalently.
Small biological experiments that could improve vaccines and cancer treatments will also benefit. Right now, running out of something as simple as a bottle or closable container can put an experiment on hold. With a 3D printer on board, the ISS will never run out of basic equipment again.
One of Dunn and Kemmer’s biggest future goals is to print CubeSats aboard the ISS. CubeSats are 4-inch-wide cubes that serve as functioning satellites. After being contacted by an interested client, Made in Space developed a CubeSat that can be assembled in less than a minute. Of its nine pieces, seven can be 3D printed.
CubeSats are easy to work with and develop experiments for, and, as a result, Dunn said 1000s of students design them every year. But very few make it into space. A 3D printer will make it possible to order and launch one in a week. Their numbers in space are expected to boom.
In the far future, Kemmer sees 3D printers wandering much farther from Earth than the ISS. They’ll benefit human colonists on Mars and companies and nations that mine asteroids for natural resources.
“We’re not just focusing on printing on the space station,” Kemmer said. “We’re going to get to one day where we’re printing space stations. We’re going to manufacture large spacecraft on demand.
This story was updated at 11:45 a.m. PT on July 23 to remove several photographs that showed the interior of the 3D printer. NASA informed Made in Space these photos might violate International Traffic in Arms Regulations.