A biosuit allowing astronauts to wear form-fitting spacesuits is closer to reality due to new technology developed by researchers from the Massachusetts Institute of Technology (MIT). They have invented a new device that could lead to a new generation of wearable gear for astronauts.
Spacesuits have traditionally been bulky and stiff, making it difficult for space travelers to carry out their duties. This is partly due to air filling the suit, for breathing and pressure.
Astronauts using the new suit for space walks will slip into the highly-pliable garment, then plug it into a power coupling in the spacecraft. Specialized muscle-like coils in the suit will then contract, shrink-wrapping the space traveler inside the biosuit. After coming back inside the ship, the next-generation spacesuit could easily return to its previous loose-fitting condition. This overcomes one of the major challenges faced by previous designs of skin-tight spacesuits - how to get in and out of the ultra-snug garments.
Tiny shape-memory alloy (SMA) coils, resembling springs, contract when exposed to heat. These materials have a "memory" of the shape in which they are manufactured, and return to shape as they start to cool. As coils contract, they provide enough pressure on the spacesuit to sustain life in astronauts, without the need for fully-inflated protection. This is equal to about one-third of normal air pressure on the surface of the Earth.
"We want to achieve that same pressurization, but through mechanical counterpressure - applying the pressure directly to the skin, thus avoiding the gas pressure altogether. We combine passive elastics with active materials... Ultimately, the big advantage is mobility, and a very lightweight suit for planetary exploration," Dava Newman, professor of aeronautics and astronautics and engineering systems at MIT, said.
A nickel-titanium shape-memory alloy (SMA) was used to manufacture the small coils. This material is normally manufactured in long cables. Coils were created from the wire through the use of a technique designed to manufacture robotic worms, invented by fellow researchers from MIT.
Coils manufactured from SMA were set into shape at temperatures over 840 degrees Fahrenheit. After, these devices became pliable at room temperature, allowing an astronaut to easily change in and out of the new suit. Heat causes the coils to tighten over the body of the space traveler.
Newman and her team have not yet constructed an entire new suit, but the coils represent a technology that could lead to form-fitting space wear. One challenge facing the MIT researchers is how to keep the coils locked in place once they contract. Keeping the suit heated would be uncomfortable or dangerous for the wearer, so future investigation will study a possible locking mechanism for the tiny coils.