Future spacesuits could act like protective second skin
- 19 September, 2014 08:10
As NASA works to one day send astronauts to asteroids and eventually to Mars, the space agency is also looking for new spacesuits that will keep the astronauts safe, while enabling them to move freely.
Scientists at MIT say they are making such a spacesuit -- one that is less bulky than the typical gas-pressurized suits and more like a second skin.
"With conventional spacesuits, you're essentially in a balloon of gas that's providing you with the necessary one-third of an atmosphere [of pressure,] to keep you alive in the vacuum of space," said Dava Newman, a professor of aeronautics and astronautics and engineering systems at MIT, in a statement. "We want to achieve that same pressurization, but through mechanical counterpressure -- applying the pressure directly to the skin, thus avoiding the gas pressure altogether... Ultimately, the big advantage is mobility, and a very lightweight suit for planetary exploration."
Newman has worked for 10 years to design a form-fitting, flexible spacesuit. She's found the material needed and the technology to build a suit that is not bulky like the suits that astronauts wore to walk on the moon more than 40 years ago and as recently as on a spacewalk (ast month.
The new technology could also lead to spacesuits that are lightweight, stretchy and form to an astronaut's body like a shrink-wrapped second skin.
This second-skin spacesuit is expected to be built out of a nickel-titanium shape-memory alloy, a smart material lined with tiny muscle-like coils that contract when heated. The material "remembers" an engineered shape and, when heated, can spring back to that shape.
When heated, the material compresses with so much force that it acts as a pressurized suit, equaled the pressure required to fully support an astronaut in space. Pressurizing the body without a bulky, gas-pressurized suit, would give the astronaut much more freedom to move about and do their work.
To take the suit off, the astronaut would only have to apply modest force, returning the suit to its looser form, according to MIT.
NASA astronauts rely on spacesuits to protect them from a harsh and dangerous environment while they are working in space.
For missions to Mars or into deep space, the space agency is looking for a spacesuit that will protect astronauts but also allow them to easily move and work on rocky ground or in slippery sandy conditions.
At MIT, researchers tested the smart material using a tourniquet-like cuff.
They applied a current to the cuff to generate heat. When the cuff reached a specific temperature, the coils inside the material contracted into their "remembered" form, just as they would need to in order to form a second-skin-like spacesuit.
"These are basically self-closing buckles," said Bradley Holschuh, an MIT Ph.D candidate, who conceived the coil design. "Once you put the suit on, you can run a current through all these little features, and the suit will shrink-wrap you, and pull closed."
The next step in the researchers' work will be to figure out how to keep the suit tight after it's initially triggered.
According to MIT, the scientists are working on two options -- maintaining a constant temperature running through the suit or building a locking mechanism into the coils. The researchers are focusing on the locking mechanism since the other option easily could overheat the astronaut and require them to carry heavy battery packs.
NASA is helping to fund the research.