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New designs may lack the flare of the Z-1, but improve technically

The U.S. National Aeronautics and Space Administration (NASA) in 2012 ignited a frenzy of praise, criticism, and just plain hype when it announced that it was redesigning its Extravehicular Mobility Unit (EMU) spacesuit.  Now that suit has been replaced and the process begins anew as NASA and its contractor push the design closer to field deployment.

I. Advancing the Spacesuit

Spacesuits, commonly known as extravehicular activity (EVA) suits, allowed astronauts to operate outside spacecraft and space stations while in orbit or on the Moon.  NASA's spacesuits won praise for their solid performance and relatively low costs -- attributes that came thanks in part to their production by a private sector contractor.

However, they also earned some criticism for their slow evolution.

EMU Suit
The EMU suit was used for Space Shuttle EVA sessions.

Derived from the Apollo programs A7C/L/LB series suits, the EMU suit was in use from 1981 until 2011, tweaked at times, but remaining largely unchanges over its thirty year tenure.  The EMU suits were produced by International Latex Corporation (ILC) Dover -- a Frederica, Delaware contractor that was founded by Playtex (women's undergarments) inventor Abram Spanel.  The suits were codesigned by veteran propeller maker Hamilton Standard, a company that is today part of United Technologies Corp. (UTX).

The 2012 redesign was never fielded, but brought ambitious changes to the tried-and-true EMU.  Most notably, it was a fully flexible suit, offering new zero-gravity (zero-G) work opportunities.

The Z-1 prototype
The Z-1 prototype, aka the "advanced EMU" or "Buzz Lightyear suit"

At 126 lb (57 kg) the much more flexible Z-1 suit was slightly heavier than the EMU -- a suit that weighed 109 lb (49.4 kg).  However the Z-1 allowed a so-called "Suitport", basically a miniature port that opened into a suit hanging off the side of the spacecraft or space station.  This development was in part enabled by the fact that the suit was designed to operate at 84 pressure settings -- including pressures from 0 and 8.4 psi (0 to 0.571 atm).

The EMU suit traditionally operated at 4.3 psi (0.293 atm).  In preparation for a spacewalk an EMU users had to first spend 24 hours in a cabin that had been dropped from 14.7 psi (1.000 atm) to 10.2 psi (0.694 atm).  The user then prebreathed for 45 minutes.  

Z-1 Suit prototype 2
An astronaut picks up a rock, showing off the flexibility of the new suit.

While astronauts will likely still have to follow a similar spacecraft/space station depressurization in lead up to a Z Series spacewalk, if they had to evacuate into the suits directly from standard cabin pressure (14.7 psi), it wouldn't be catastrophic.  Further, the lengthy prebreathing exercise is eliminated and astronauts face a decreased risk of decompression sickness.

By eliminating the need for pre-breathing and the need for a dedicated decompression chamber, astronauts could signficantly decrease the weight of future spacecraft or spacestations, making up for whatever marginal increase in weight the Z Series suit brought.

II. The Next Generation -- Bye Bye Buzz Lightyear, Hello Gray

The Z-2, the successor to the Z-1, has just been announced, with the public getting to vote on a handful of competing stylings to the suit's exterior.  Like the Z-1, the new Z-2 features three central components -- the soft upper torso, soft lower torso, and hemispherical dome helmet, along with four assemblies, one for each limb (the glove and boot assemblies).

The Z-1 suit was developed by ILC Dover.  For the Z-2 suit a cash-strapped NASA allocate a decent chunk of financing to the project -- $4.4M USD.  ILC Dover faced competition from David Clark Company, Inc. -- a microphone maker that at times moonlighted as a suit designer.  David Clark produced the Advanced Crew Escape Suit (ACES) -- the pressured orange "pumpkin suit" that was worn by later Space Shuttle astronauts during takeoffs and landings.

In April 2013 NASA announced ILC Dover won the contract [PDF].

Now, roughly a year later, ILC Dover is showing the first fruits of its labor on the second phase design.  The Z-2 suit makes certain concessions -- notably a hard composite upper torso section -- in order to achieve the durability needed for real use in space.  The hard torso is still a significant step forward over the EMU as NASA says that it will be the "most conformal and re-sizeable hard upper torso suit built to date."

The Z-2 is thus expected to have less shoulder and back mobility than the Z-1, but still have similar lower leg mobility.

The boot assembly is also beefed up and brought up to full pressure.

Emerging rapid prototyping technologies -- namely 3-D laser scanning and 3-D printing -- were put to use for the first time in a major EVA suit design project, allowing ILC Dover to deliver the suit ahead of schedule.

ILC Dover collaborated with design and engineering students at Philadelphia University which submitted its own artistic suit stylings [1, 2] as part of a Dec. 2012 (Fall 2012 semester) design contest.  The cream of that crop survived to the current phase and ILC Dover and NASA has put them up to a public vote.

The vote on the new designs -- "Biomimickry", "Technology", and "Trends in Society" will last through April 30.  For fans of the original green and white styled suit (that looked rather like Toy Story hero "Buzz Lightyear") sadly that is not an option.

Biomimickry -- Design 1
Biomimickry
Z-2 "Biomimickry" (Design 1 of 3)

Many of the designs incoporate biolumniscent wire flourishes that don't just look cool, but may also provide mild lighting while performing space duties.

Z2 Technology
Z2 Technology seriesZ-2 "Technology" (Design 2 of 3)

Voting runs through April 15 (Tax Day) and the winning design will be announced April 30.

Z2 Trends in Society
Trends in SocietyZ-2 "Trends in Society" (Design 3 of 3)

ILC Dover expects to deliver a finished suit in November 2014. This will allow NASA time to start testing the next-generation Portable Life Support System (PLSS) which has been under design in-house via NASA's major Next Generation Life Support (NGLS) project [PDF].  More specifically, NASA will test various competing ideas for the suit's Variable Oxygen Regulator (VOR) and the Rapid Cycle Amine (RCA) swing bed.  The VOR provides the astronaut with a pressurized, breathable environment, while the RCA scrubs the carbon dioxide the astronaut exhales from that environment.

PLSS
A next-generation life support module will accompany the new suit. [Image Source: NASA]

NASA is currently weighing a disposable lithium hydroxide (LiOH) canister based scrubbing design for the VOR versus a metal hydroxide design.  The former design can be quickly replaced, but adds to launch weight and costs.  The latter system takes time and electricity to "recharge", but can be reused multiple times, potentially cutting launch weight and costs (both in the cost of additional fuel and in the cost of replacement).

The suits will be tested next year at NASA's human-rated vacuum chamber and the Neutral Buoyancy Lab.  After that, by 2020 they will be tested fully with the finished PLSS in a more intense thermal/vacuum chamber that simulations a space environment.

III. SpaceX + Advanced EMU = NASA's Future of Manned Flight

NASA is expected to regain its own domestic launch options before that time. Elon Musk's SpaceX is striving to have a human-rated resuable Dragon capsule, part of the company's Commercial Crew Development (CCDev) project, ready by between next year and 2017.  The next-generation Dragon capsule is expected to operate alongside the Z-2's finished successor and likely be retrofitted to feature suitports once the finished suit is fielded sometime in 2020 or later.

SpaceX has 50 successful commercial launches scheduled or completed -- two-thirds of which come from commercial customers.  It is currently fielding its latest and greatest Falcon9 v1.1, one of the most powerful commercial rockets ever produced.  The upcoming Falcon Heavy -- set to lift the human-rated Dragon -- will be more powerful than any other rocket produced by man, save perhaps the Moon-rated Saturn V used by the Apollo program.

A year ago from this month SpaceX performed its third succesful resupply run to the International Space Station (ISS), using a Falcon9 and its unmanned, robotic Dragon capsule.  That launch suffered some minor hiccups, but SpaceX is believed to have ironed out these issues.

Elon Musk
Elon Musk is planning a manned Dragon launch using a Falcon Heavy rocket sometime in 2015-2017. [Image Source: AP]

SpaceX remains private and despite its substantial commercial revenue is also deeply subsidized by Mr. Musk's own fortune.  In June 2013 the visionary leader quipped that a SpaceX public offering wouldn't be in the works until the "Mars Colonial Transporter is flying regularly."

But the statement isn't just a joke.  Elon Musk is actually prototyping a successor to the manned Dragon, dubbed the "Red Dragon", which will first perform automated Martian mining and eventually take humans to Mars.  So get ready to invest by around 2030-2040.

[All Images other than the SpaceX one are from NASA/ILX Dover]

Sources: NASA's Johnson Space Center -- Suit Vote, NASA - Advanced Suit Development News and Features, Philadelphia University [1], [2]





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