I recall when
the first space suits for the Apollo program were shown of that I felt a sense
of disappointment tempered by the knowledge that it was a starting point to
evolve from. Now here we are attempting
to evolve. It is still not too impressive.
The advent of
graphene will provide and impervious outer shell in time, but we are not there
yet. Yet joint technology was improved
hugely with the deep sea hard suit and should be adjusted into the space
environment.
I would also like
to see gloves with natural soft points that allow serious tactile
feedback. I suspect it can be done. The back of a finger of thumb digit can be
stiff to avoid compromising forward movement and squeezing. Hinging can reflect natural bone hinging as
well.
NASA testing
lighter space suits for asteroid work
By David Szondy
December 15, 2013
Sometimes you have to take a step back to take a
step forward. NASA is carrying out initial tests on a new, lighter spacesuit
for use by the crew of the Orion spacecraft that
is currently under development. The tests are being carried out in the Neutral
Buoyancy Laboratory near the Johnson Space Center in Houston, Texas on a
modified version of the pumpkin orange suit normally worn by Space Shuttle
crews during liftoff and re-entry and is a return to a space suit design of the
1960s.
The Orion program has posed something of a wardrobe
problem for NASA. When the space agency started looking at developing a new
spacesuit for the 21st century, it had the now-cancelled Constellation
spacecraft in mind. The original plan was to go with either armor-like hard
suits or something along the lines of the hard/soft hybrid Extravehicular
Mobility Unit (EMU) suits deployed on the International Space Station (ISS) for
extravehicular activities (EVA).
The hard and semi-hard suits, such as the Z-1 prototype, are
bulky with lots of hard shells, bearings, hatches, and other components. This
isn’t a problem on the station or in a large vehicle like the Space Shuttle or
the Constellation, but when the Constellation program was cancelled in favor of
the Orion, all that hardware had to go out the porthole. Orion is more of an
upgraded Apollo Command Module and space will be at a premium. There isn’t room
for a specialized EVA suit that looks like it was designed for jousting with
laser beams.
That’s a stumbling block because NASA wants to use
Orion to send a manned mission to collect samples from an asteroid relocated
to an orbit near Earth. This means the Orion crew needs spacesuits for the
EVAs, which means a different kind of space suit is required.
NASA’s solution is to take a step backwards. Instead
of having one suit for launch and reentry operations, and another for EVAs, the
space agency wants a multi-purpose spacesuit that can be worn for both flight
operations and for working outside the spacecraft, as was the case up to the
Apollo-Soyuz mission in 1975.
The new suit is a harkening back to and an evolution
of the suit worn by Ed White during his historic spacewalk during the Gemini 4
mission in 1965. When the US space program started, the first “spacesuit” worn
by the Mercury astronauts was a modified Mark IV high-altitude suit painted
silver. For the Gemini missions, a new suit was developed that was an advanced
version of the suit worn by SR-71 Blackbird pilots as they flew on the edge of
space at supersonic speeds.
Both of these were suits designed mainly to protect
the wearer in the event of a sudden loss of cabin pressure. Since the astronaut
spent most of his time sitting down, and would certainly be doing so in an
emergency, the suits didn’t allow much in the way of mobility when inflated.
The biggest advance came when the Gemini astronauts
started doing spacewalks and the suits had to be modified with more flexible
joints and gauntlets, so the astronauts wouldn’t be floating around looking
like crouching balloons, and could get in and out of the spacecraft with a
minimum of effort and cursing.
When Apollo came along, the designers had to make
something that someone could actually walk in and get some work done in while
inflated. That worked fine for the moonwalks, Skylab, the Space Shuttle
program, and the ISS, as suits became bulkier and incorporated more hard
components to provide more mobility and a one-size-fits-all design.
The new Orion suit is based on the Advanced Crew
Escape System (ACES). Like the Gemini spacesuits, this too is a development on
the flight suit for the SR-71 Blackbird. Notable for its distinct pumpkin
orange color, it was worn by Shuttle crews from 1994 on. Its current purpose is
to protect the astronaut in the event of an emergency, to provide life support
for a very limited time, and to carry emergency gear, such as parachutes,
flotation devices, radios, and survival kits.
According to NASA, the advantages of the ACES suit
are that it has over 30 years of experience behind it, is low cost, the
infrastructure for supporting it is already in place, and it’s designed to be
easily upgraded. Though it will be modified for working in hard vacuum for
extended periods, the new suit will look very similar to the current ACES,
except that it will be white instead of orange.
The main modifications to the suit will be to make
it more suitable for regular work instead of just emergencies. It will need to
operate with a life support backpack and the systems on Orion, operate for
hours instead of minutes, and it will need more flexibility in the elbows,
wrists, and other high mobility joints. The trick will be to do so without
introducing too many hard points that might injure the wearer on take off or
hinder an escape in an emergency.
"The shell of them is very much the same, and
to the casual user you may not even notice the difference, but internally we
modified them to work with the plumbing inside Orion," says Dustin
Gohmert, Crew Survival Systems Manager at Johnson.
The neutral buoyancy tests and others involving dangling
from harnesses and crawling through Orion mockups are designed to assess the
suitability of the ACES suit for EVAs and to find out what modifications need
to be made. This is a bit tricky because its a constant tradeoff between
efficiency in moving around, which favors shells and bearing rings, and as an
emergency suit for walking to the launch pad and being worn during flight,
which benefit from everything being soft. The tests will also help engineers to
evaluate spacewalking techniques, such as getting through hatches, moving
between spacecraft and asteroid, and handling tools.
"We're stepping back to our heritage to be able
to use one suit for multiple tasks," says Gohmert.
The video below shows part of the water tank tests.
Source: NASA
No comments:
Post a Comment