Until a year ago, commercially printing objects in space was the stuff of science fiction. Not anymore. At any given time onboard the ISS National Lab, a 3D printer receives data files from Earth that it transforms, layer by layer, using plastics, into fully functional tools and parts that ISS crew members can use.
This March marked one year since the Additive Manufacturing Facility (AMF) was launched as a permanent “machine shop” on the ISS, providing in-orbit fabrication services to customers from both the ISS National Lab and NASA.
The AMF, owned and operated by California-based Made In Space, has come a long way from its origins as a proof-of-concept payload launched to the ISS in 2014. That initial prototype proved that 3D printing in microgravity actually works and that there was commercial demand for parts Made In Space. Today, the AMF continues to produce objects on-demand not only for NASA but also for a multitude of commercial companies, fueling the growth of a new economy in low Earth orbit.
Ken Shields, director of operations at CASIS, sees several tangible and intangible benefits of being able to manufacture objects off the planet. “Theoretically, you could accelerate completion of end-to-end experimentation in orbit by exchanging out components in near real time as opposed to waiting for results and then sending up parts.”
Before the AMF, any spare parts for the ISS and materials or tools required for experiments on the ISS had to be transported from Earth on a launch vehicle and stowed away onboard until (or if) needed. With the AMF, an ISS crew member or user on the ground can custom design, print, and manufacture an object on demand on the ISS, with the ability to do multiple iterations.
“We can deploy much faster,” said Andrew Rush, Made In Space president and CEO.
As an example, Rush shared how quickly the team designed a ratchet for ISS Commander Barry Wilmore in 2014 using the prototype microgravity 3D printer. The ratchet was the first tool ever to be designed on the ground, emailed to space, and printed in orbit.
The AMF builds upon that first prototype unit. The new commercial facility is larger, modular, and upgradable. From a capability standpoint, the AMF can both scan and verify the accuracy of the parts it prints with no user involvement.
While the AMF currently uses three types of thermoplastic polymers, it will support other feedstock as demand and applications grow. The plastics available now include: acrylonitrile butadiene styrene (ABS), the same material used to make LEGO® blocks; a high-density polyethylene (HDPE), such as the type found in home food containers; and an aerospace-grade polymer (polyetherimide polycarbonate or PEI-PC). Longer term, Rush and others could see these raw materials eventually recycled from other parts or recovered in situ from the moon or other planets.
"We went from idea to part on station in a week. That is an order of magnitude faster than the traditional way of sending things to space,” Rush said.
Space-based manufacturing eliminates the need to design for the high shock and vibration of launch, which often results in products being over-designed, Rush said. “Making things in space allows us to actually optimize the design for the space environment rather than for the transportation system.”
3D Printing in Microgravity
How does 3D printing in space work? Like an Earth-based 3D printer, the AMF uses an additive manufacturing method to print objects in layers of plastics, metals, and other feedstock materials. Made In Space relies on a 3D additive manufacturing technology called fused deposition modeling. Heating up the filament to a molten state, the material is precisely deposited through a trigger head in a back-and-forth pattern—layer by layer—until the part takes form.
"There are 3D printers that a lot of people might be familiar with that use this same technique,” said Rush. “To make it work in space, you need to eliminate gravity from the equation—everything from positioning of the head and the part, to how the material gets deposited, to making sure it sticks to itself, to managing the heat control.”
Moreover, the free-fall weightless environment of space results in the absence of convection, “so you need to make sure the hot parts stay hot and the cold parts stay cold without the benefit of natural convection,” Rush said.
From Early Version to Printing Space-Optimized Tools
Made In Space has come a long way from the early days of proving its design. Initially the founders hoped to “buy a commercial off-the-shelf printer and tweak it until it could turn upside down and function as a space-capable printer,” said Rush.
The team spent many sleepless nights testing and retesting their design. They fine-tuned the printer during two weeks of parabolic flight testing, which was critical to proving the design.
The final system, designed to operate from the ground with no ISS crew member involvement, met NASA’s requirements for reliability, safety, and self-sustaining performance. The AMF can use a wide variety of materials as feedstock because it regulates temperature and humidity. Its own environmental control system also keeps the materials within appropriate levels of containment, a required safety regulation for ISS hardware and facilities. Interestingly, this containment feature has been incorporated into 3D printers on the ground.
Made In Space engineers on Earth control the AMF’s queue of print jobs, while internal cameras allow the company to monitor the printer’s operation and notify NASA when an object is printed and ready for retrieval by an ISS crew member.
Since the AMF began full operations this past summer, it has printed more than a dozen objects, including a spaceoptimized wrench designed by Lowe’s Home Improvement Stores for the ISS crew members to clip on their belts to more easily perform repairs. Made In Space has designed numerous other ISS tools, including a sensor adapter, hose adapters, and spacecraft parts.
Made In Space already has a six-month backlog of print orders. Besides NASA, AMF customers include private companies, private individuals, universities, K-12 schools, and other government agencies.
A LEO Commercial Space Economy
Given the types of novel ideas already being generated, tested, and printed on the AMF with partners like Lowe’s, CASIS’s Shields believes the future is bright for the AMF on the ISS and that it will grow to become a critical component of building a sustainable commercial presence in low Earth orbit (LEO).
"The queue of projects and potential customers that want to work with Made In Space indicate there is demand for this on the commercial side,” Shields said. “What they are doing is disruptive—it’s thinking outside the box. These are the kinds of companies that are going to lead the way in the LEO commercial market.”
According to Shields, hundreds of millions of dollars have been invested to date by commercial players testing the waters for building a business in low Earth orbit, often using the ISS National Lab as their test bed. In the last year alone, approximately $75 million has been invested in LEO projects and activities.
Made In Space is one of five companies now managing in-orbit commercial facilities on the ISS, a service provided by only a couple of companies just five years ago. By 2018, at least nine companies will be managing commercial facilities on the ISS, which together will total $100 million in commercial investments in the LEO space sector. The AMF is a critical part of that future, said Shields.
“The ability to manufacture things in space will be critical for us going beyond low Earth orbit to occupy other regions of space, be it other planets or other orbiting bodies,” Shields said. “The applications are endless as far as manufacturing parts and components to sustain oneself in the ultimate remote location.”
Looking at how far Made In Space has come—from idea to operational manufacturing service in the span of six years—Rush cannot hide his excitement. “I think that’s an incredible pace.”
Rush and his colleagues have no intention of slowing down. “The design space is so broad, we are just seeing the very first applications of additive manufacturing,” he said. “I view the LEO economy, especially in-space manufacturing, as the next gold rush—we aim to expand utilization of space in as dramatic a way as possible through commercial activity on the AMF.”