A Silicon Valley startup has an out-of-this-world application for additive printing technology – literally. Made in Space, Inc. is developing 3D printing equipment that future space explorers could use to fabricate replacement parts during their journey. Current mission planning requires that crews bring any replacement parts or tools with them or, as in the case of the International Space Station, wait for a regular replenishment mission. Launches aren't practical for an unexpected small part or tool and become more problematic as missions depart Earth's orbit.
This is where additive manufacturing steps in to offer a possible solution. The technology, which creates objects by building up subsequent layers of materials as directed by CAD files, would allow astronauts to manufacture replacement parts on location, rather than on Earth prior to launch. Future space explorers could reserve valuable real estate on their shuttles for other supplies if they could rely on a 3D printer to make needed replacement parts. And while the technology is not quite on par with the Star Trek Replicator, it is a vast improvement over taking up vital shuttle space with a myriad of spare parts.
While the technology has great potential for future space missions, there are still roadblocks involved in transporting a 3D printer into space. Just like transporting replacement parts manufactured on Earth, the bulk of additive manufacturing infrastructure is considerable, and, as always, minimizing weight is vital for a shuttle to reach orbit. Furthermore, the 3D printer components need to be flight certified prior to launch. Finally, once the parts arrive at their extraterrestrial destination, they need to be assembled by a qualified team of engineers.
However, this does not address the physics of printing in space, which requires that the printers be adapted for null-gravity environments. Made in Space's solution involves extruding a polymer-based material through a nozzle, but it is debatable whether this is the optimal approach. Karen Taminger of NASA's Langley Research Center in Virginia is working with a metal-printing technique involving an electron beam that acts as a soldering iron to melt metal wires before depositing the metal in layers. This method would be ideal for near-space applications, as the electron beam requires a vacuum, which, Taminger notes, you have for free in space.
Like Taminger, Made in Space aims to test their 3D printer at the International Space Station. But until much needed funding comes through, this adapted technology may make it into space for testing only.
Despite the limitations funding may pose, the Made in Space team remains optimistic. In a recent trip in a modified Boeing 727, they were able to print and use a wrench during eight minutes of weightlessness. With any luck, that won't be the last tool the team manufactures having slipped the surly bonds of earth.
Full Story at Smithsonian Air & Space Magazine