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NASA has a long history of backing the research necessary to deliver fabrics that could withstand the extraordinary rigors of Space. Evelyne Orndoff is the Soft Goods Development and Testing Lead, Crew and Thermal Systems Division, for NASA. In her presentation at the Emerging Technologies Conference at ATA’s Expo, she discussed these historical fabrics, explaining how and why some are still in use, and some are not.
Faced with its current challenge—the South Pole of the Moon—the agency is looking for the next generation of history-making fabrics. About the Moon’s South Pole, Orndoff says, “This is the worst place to go. Nothing is round. [The regolith] is like glass, and it’s sharp down to the micron scale.”
Furthermore, as she explained in a campfire session on the show floor, when a vehicle lands on the Moon’s surface, a plume of regolith—the loose dust and broken rock—will be kicked up, which will keep going up as much as a kilometer, and then hang in the environment for a long time. “The biggest challenge is a material that will not be damaged by that regolith,” she says. The same need applies to containers for gear, such as for cameras and material samples.
Furthermore, it’s “the dark side of the moon,” with a sunset every 90 minutes and temperatures that can plummet to -200C (-390F). Extravehicular (EV) suits will have to withstand these conditions and for longer periods of time. Materials designed earlier could withstand short spacewalks, but requirements and standards have changed. “We need to make new fabrics that pass the new tests,” she says.
As EV suits are constructed of many layers of fabric, some of those fabrics will still prove useful. Beta silica fiber at 3.8 microns is the smallest fiber used. “You have to stretch the fibers so it’s very, very fine,” she says. In fact, NASA’s supplier at the time had to build a special plant. “This is the contender,” she adds.
Polybenzimidazole (PBI), used in the CETA (Crew Equipment Translation Aid) carriage housing, which is part of an extravehicular transportation system and the airlock hatch bumper, must be shrunk first because it shrinks under heat. Durette, a modified aramid, has been used extensively and is still being used in some applications, she says. Fluoroelastomer is still used and continues to be needed for multiple functionalities and applications. The EV suits also need a super absorbent material for urine collection, as astronauts can’t break to go to the bathroom when they’re in the suits.
Even with all the layers—there are 13 of them—Orndoff stresses the need for a system that is lighter and not as bulky. “We are working to adjust mass and volume for the activities [of the astronauts],” she says. “If the crew doesn’t like it, forget it. It’s not going to fly.”
Several other fibers and materials were discussed, including high-strain graphite composite; polyimide, which is an ultraviolet radiation-stable fiber; polyolefin fibrous structures, which are desirable because they’re so light—“It’s so expensive to launch anything in Space” she says, so weight is important—but they’re also flammable, so that has to be addressed. All components need to pass stringent fire-retardant tests.
The commercialization of aerospace
A panel discussion, moderated by Haskell Beckam, Ph.D., vice president, innovation, Columbia Sportswear, took the discussion into commercial Space enterprises, now benefiting from private and government partnerships. Chyree Batton, Ph.D., is commercial innovation strategy lead-advanced materials, in-Space solutions, with Axiom. Her company is working with NASA to develop its spacesuit for the Moon, but her company’s mission is to “expand space access to all.”
Most recently, the company partnered with Prada, which she explained is not just a high fashion business, but, in fact, has “extensive experience developing composites,” which they created for competitive sailing. “Partnerships save costs, as well as tapping into others’ expertise,” Batton says.
The new spacesuit will have three sections and 11 different layers, she explained, which must address multiple requirements. For example, heat doesn’t rise in space, so body heat must be captured. The suit needs to be pressurized, and to protect from solar heat and micrometeorites that pose ballistic dangers. Axiom, she says, will eventually standardize spacesuits, including sizing for females, to accommodate more space travelers.
Matt Reid, with the Vectran® Fiber Division of Kuraray America Inc., admitted that Vectran is a very expensive material, but besides its protective functionalities, it “actually gets stronger as it gels to extremely cold temperatures,” and it’s also lightweight. This has given it a new use in the “Life Habitat Project,” an inflatable structure that attaches to the ISS. “Because it’s inflatable, there’s a huge cost savings,” Reid says.
In a separate presentation, Reid showed a video of an ultimate burst pressure test on the one-third scale model of the inflatable space habitat. The Large Inflatable Flexible Environment (LIFE™) habitat will be part of Orbital Reef, the first commercial space station, under development by Sierra Space, Blue Origin and ILC Dover, among others.
Reid discussed the properties of liquid crystal polymer (LCP) fiber and how it compares to para-aramid fibers, such as Kevlar®, and high modulus polyethylene (HMPE), such as Dyneema®. LCP fiber has characteristics of both other types, but the crystalline structure is what makes it so strong and able to replace steel in some applications, such as portable hangars for the military. Other applications include tethers, inflatable tunnel plugs, slings, aerostats, mooring ropes and protective firefighting gear.
How to access research in Space
Also at the conference, Jason M.F. Smith, customer solutions and business development lead, Aegis Aerospace, explained how his company provides access to Space with equipment and services for testing. Given the harsh conditions there, tests on the International Space Station (ISS) offer a unique environment, including microgravity, the presence of radiation, temperature extremes, atomic oxygen (as opposed to the O2 we breathe) and a lack of contamination.
It’s especially valuable for testing durability. “You’re testing for accelerated aging,” Smith says. “A product will last as much as 10 times longer on Earth.” In fact, access to the space environment has accelerated textile design, development and testing, he says, and has also made new materials available for terrestrial uses.
Fiber developed by W.L. Gore, for example, was used in spacesuits designed for astronauts on the Columbia, NASA’s inaugural space shuttle mission. These products continue to be used in a variety of applications and markets today.
Aegis’ equipment, called MISSE, is carried on the International Space Station (ISS) and offered through the company’s proprietary program, Space Testing as a Service (STaaS™). Recently, for example, Sierra Space’s LIFE Habitat was tested as a way to transport shelter for astronauts into Space. “
Producers who wish to have a product tested in Space should first consider the environment in which the material will be used, the load that the material will be subjected to, the desired lifespan, and any other properties required of the material. Products may use ground-based tests that simulate the conditions of Space, computer simulations or Space-based testing, such as on the ISS.
There are also a variety of ways to access Space testing, including contacting NASA or the ISS Laboratory. There are also commercial providers, such as Aegis Aerospace; but also Axiom Space which is building a commercial space station with the goal of manufacturing objects in space; Nanoracks, which provides payloads services to the ISS; and others.
The United States is currently a leader in advanced materials research and development, but to maintain its leadership, the U.S. needs to continue to invest in R&D for advanced materials.
Capitalizing on Space access via the ISS technology platform can drive game-changing innovation and products that benefit mankind right here on Earth, Smith says.
He also shared a quote from astrophysicist Dr. Juliana Cherston to underscore the importance of textiles in extreme environments: “Alas, until it is possible to substantially alter the human body, the humble textile will continue to serve as a boundary—a second skin—for the arctic explorer, for the deep-sea diver, and indeed for the astronaut.”
Janet Preus is senior editor of Textile Technology Source. She can be reached at janet.preus@textiles.org. Cathy Jones is senior editor of Specialty Fabrics Review.