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Quest for a perfect Space Suit : A NASA effort

A space suit is a special clothing system worn to keep human alive in the harsh environments like outer space, vacuum etc. Space suits are predominantly used inside spacecraft as a safety precaution and are mandatory clothing for extra-vehicular activity (EVA) i.e. activities done outside spacecraft. Space suits are needed for walking in Earth orbit, on the lunar surface and on way back to Earth from the Moon.

Russian Space Suits:

American Space Suit:

Space Suits are life saving devices rather than a normal insulated clothing. The human body can survive the hard vacuum of space for a very short period. Human flesh expands substantially in such conditions and look like the body of a body builder. It takes about 15 to 18 seconds or so before human lose consciousness because of oxygen starvation. It takes some time for the body to lose heat lost through thermal radiation and the evaporation of liquids. Despite extreme low or no pressure the blood remains pressurized within the body rather than start boiling suddenly. One can hold the breath for some time but subsequent explosive decompression can damage the lungs. All these have been studied and confirmed through various accidents happened at very-high-altitude conditions or in training vacuum chambers. Human is gas-tight and so it is only needed to be mechanically compressed. A tight-fitting elastic body suit and a gas tight helmet with breathing gases provision makes a good space activity suit (SAS).

Because of above, modern space suits are complex. The basic requirements of a space suit are the following:

Providing a basic pressure garment with equipment and environmental systems

Keeping the wearer comfortable and facilitating smooth movement

Resisting a soft pressure garment’s natural tendency to stiffen against the vacuum

Deploying a self-contained oxygen supply and environmental control system

A good design of space suit should be able to perform the following critical functions:

A stable internal pressure. Interestingly, the pressure inside the suit can be lower than atmospheric pressure as in our normal atmosphere of the Earth there is about 78% Nitrogen, which is not needed critically by the body. In fact lower pressure in the spacesuit allows a greater mobility.

Mobility. This is a critical requirement. For safety in extreme environment this is something which should be attained without fail.

Supply of breathable oxygen and elimination of carbon dioxide from the space suit is a critical requirement. High level of carbon dioxide will make human body unconscious. Generally the these gases are exchanged with the spacecraft or with a device called Portable Life Support System (PLSS)

Temperature regulation. Remember that Unlike on Earth, there is no convection heat transfer. Heat transfer happens by radiation or direct contact with external object with space suit (conduction). Keeping in mind the extreme fluctuation of temperature between sunlight and darkness efforts are made to keep the temperature maintained at a comfortable level.

A communication system is critical and can be life saving. This is done by an external electrical connection to the spacecraft or PLSS

Means of collecting and containing solid and liquid bodily waste

In addition to the above, there are various optional requirements that is needed to be built into the space suit

Advanced suits better designed to regulate the inside suit temperature by deploying a Liquid Cooling and Ventilation Garment (LCVG). This remains in contact with human skin. The generated heat is dumped into space through an external radiator in the PLSS.

Protecting from ultraviolet radiation

Limited shielding against particle radiation

Mechanism to maneuver, dock, release, and/or tether onto a spacecraft

Protection against micrometeoroids (speed up to 27,000 kilometers per hour) by deploying the garment outer layer made of puncture-resistant Thermal Micrometeoroid Garment. this was first deployed on the Apollo lunar EVA suits

Picture Note: Astronaut Edward M. (Mike) Fincke, wearing a Russian Orlan space suit during their six-month mission in ISS.

To ensure that all suits are flawless and all the functions are being performed without fail a regorous testing is very much needed. ILC Dover has made every spacesuit NASA has used since the Apollo program. This is how they test them.

NASA calls for public participation in the finalization of space suit design

During 2012, NASA revealed Lightyear-esque spacesuit design called the Z-1 aimed to improve motion and mobility. The composite hard upper torso gives it a long-term durability that is needed for planetary Extravehicular Activity (EVA). The shoulder and hip joints are carefully derived based on rigorous testing. They are not-conventional but optimized for mobility of these complex joints. The boots are closer to nature and the total suit would be suitable for a full-vacuum environment.

Subsequently, the institute has upgraded the original prototype to the Z-2 wanted to have public opinion regarding the design of the outer shell. Remember that, this opinion is only pertaining to the visual look and feature of the outer shell only.

NASA has subsequently set up a website with the three designs and invited public to vote upto April 15, 2014. The proposed designs were the following:

Design A: “Biomimicry”

The “Biomimicry” design is inspired by environment in deep ocean yet fit to survive the harshness of space. It mirrors the bioluminescent qualities of aquatic creatures found at incredible depths, and the scaly skin of fish and reptiles found across the globe. Taking the cue from some of the world’s toughest creatures, this design reflects the qualities that helps them to survive in extreme conditions.

The design is characterized by segmented pleats at the shoulder, elbow, hip and knee, and electroluminescent wire across the upper torso, which becomes prominent in reduced light.

Design B: “Technology”

“Technology” celebrates the past spacesuit achievements and yet incorporate subtle elements of the future. Usage of Luminex wire and light-emitting patches puts a new spin on spacewalking standards such as ways to identify crew members.

The design contains electroluminescent wire and patches across the upper and lower torso, exposed rotating bearings, collapsing pleats for mobility and highlighted movement. There are abrasion resistant panels placed on the lower torso.

Design C: “Trends in Society”

“Trends in Society” places the space suit in the category as available everyday clothes. One can predict that you may have to wear a protective clothing in the earth environment of the near future. This suit uses electroluminescent wire and a bright color scheme to mimic the appearance of sportswear and the emerging world of wearable technologies.

The design provides gore pleats with contrast stitching throughout in order to provide high mobility. The exposed bearing at the hip, and electroluminescent wire and patches of varying styles across both the upper and lower torso are some of the prominent features.

NASA reveals its next generation Space Suit: Tronspacesuit

“Technology”, the Tron inspired design is the NASA’s next generation spacesuit—its glass 360-degree view and integrated Heads Up Display ready to detect xenomorphs, caught public’s imagination because of its closeness to the regular sci-fi movie.

According to NASA, the suit called “Technology” won the race with 233,431 votes which is about 63% of the total votes polled.

Interestingly, NASA later revealed that the crowd favorite suit is still not fit for going in the space and it’ll rather be used on Earth for things like ground-based training and vacuum chamber tests. Till then, we all have to keep dreaming of a stylish space suit as can be seen in Star Trek or in the Star Wars movies.

Author: Technology Blog

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