How 3D printing robots will influence the future of space exploration

Entire article at: http://gigaom.com/2013/10/04/how-3d-...ce-exploration

One of the promises of 3D printing is its ability to deliver a wide array of objects to difficult-to-reach locations where supplies are scarce. Companies like Made in Space are taking that principle to space — arguably the most difficult and expensive location to deliver supplies of any kind.
Tethers Unlimited is moving beyond printing basic supplies and into printing full-scale spacecraft components. Right now, structures like satellites are carried into space within another spacecraft and then launched into orbit. That puts constraints on how those vehicles are manufactured, as they have to pack well. Some larger structures must be assembled in space after making the trip.
Tethers Unlimited recently received $500,000 from NASA to continue developing Spiderfab, a robotic 3D printing and assembly system that could build structures larger than half a mile wide in orbit. Hoyt (HAVEN’T INTRODUCED YOUR HOMEBOY YET.) believes that within two to three years Tethers Unlimited will be ready to demonstrate the technology above Earth. Within 10 to 20 years, depending on funding, there will be robots capable of assembling entire spacecraft.
http://gigaom2.files.wordpress.com/2...ng?w=708&h=419A mock up of the SpiderFab system. Courtesy of Tethers Unlimited

Tethers Unlimited is based about a half hour outside of Seattle in the unassuming town of Bothell, Wash., its headquarters tucked into an office park off the highway. It is all business in the front, but CEO and chief scientist Robert Hoyt showed me into the laboratories in the back where well-worn consumer and custom 3D printers sat among scattered tools and scale models of 3D printed space structures.
One machine, traditionally used to weave lace and other complex fabrics, is used to make the highly customized tethers — which are basically ropes for maneuvering large objects in space — for which the company is known. Hoyt said with pride that it is the only machine of its kind in the United States.
So far, Tethers Unlimited has done studies that show it makes sense money-wise to manufacture and assemble certain parts in space. While it would be possible to build an entire spacecraft in space, right now it is cost effective to make large, light parts in space and build everything else on the ground. That includes parts like solar panels, but not electronics, which are already compact enough that it doesn’t make much of a difference.
“Eventually, in the distant future, hopefully we’ll have electronics foundries and stuff on the space station and elsewhere in orbit and we can start building that stuff on orbit as well,” Hoyt said.
http://gigaom2.files.wordpress.com/2...pg?w=708&h=471Tethers Unlimited CEO Robert Hoyt

Tethers Unlimited has already produced small prototypes of different parts of the Spiderfab robotic system. It will use the NASA money to begin putting the parts together and demonstrating them on a larger scale. It will also build the first prototypes of the tools the robot will use to extrude material and assemble spacecraft components.
When you send a 3D printer into space, you need to account for how things work in zero gravity. Made in Space CTO Jason Dunn, whose company will send a 3D printer to the International Space Station next year, explained to me recently that if the cogs and belts built into printers float even a fraction of an inch, it can ruin a print. And there isn’t room for error when you’re in space.
While Tethers Unlimited will have to overcome the same problem for its printer, Hoyt thinks it can actually use the lack of gravity to its advantage.
“That itself is not going to be a huge challenge. You have to tweak little things to get it to work right,” Hoyt said. “In fact, it makes a lot of things easier. On the ground, if you want to build up a complex shape that has overhanging components, you have to support that against gravity. In zero g, you don’t have to do that. You’re freer to extrude long slender things in three-dimensional space without having to build up a whole lot of support structure for it.”
Unlike Made in Space, Tethers Unlimited’s robot won’t be working within the protective walls of the ISS. Instead, it will be exposed in space.