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Date: Sat, 13 Apr 91 02:19:37 -0400 (EDT)
Subject: SPACE Digest V13 #403

SPACE Digest                                     Volume 13 : Issue 403

Today's Topics:
	  Re: spacesuits (Was: Re: HST in-orbit Maintenance)

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Date: 13 Apr 91 01:38:02 GMT
From: agate!tsunami.Berkeley.EDU!gwh@ucbvax.Berkeley.EDU  (George William Herbert)
Subject: Re: spacesuits (Was: Re: HST in-orbit Maintenance)

In article <1991Apr12.205317.21841@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>The sort of suit Pournelle was alluding to -- the "Space Activity Suit" --
>doesn't retain pressure at all.  The suit provides mechanical support only;
>the skin is in vacuum, and is itself the pressure membrane.  Before jumping

	Using a physical restraint layer is possible, and has been researched.
We don't know how to make it work around a joint, however, so it's likely that
you'd still have pressure bladder type restraints on part of the body.
	We're considering this in the Mars Suit development.
	Known problems include fitting it... people's bodies change shape
in zero-G, and in not totally predictable ways.  Also, being _in_ the suit
will change your body shape... making it stay tight and be easy to get
into and out of is ... challenging 8-)

>However, this bulk would be a whole lot more manageable if it didn't also
>have to support a pressure membrane.  For example, the joints could use
>overlapping segments, sliding over each other, rather than having to be
>one stiff piece.  The SAS would need insulation and armor just as much as
>the current suits do, but this could be a non-pressurized non-airtight
>overgarment.  (In fact, it is important that it not be airtight, since
>SAS cooling is by sweating into vacuum.)

	Our current Mars Suit concept has seperate layers like Henry
is describing.  Specifically, an inner layer that's the pressure suit,
and several outer layers (insulation, and tear/dust protection on the 
outside) which aren't physically connected to each other.


  == George William Herbert ==   * UNIX ate my last .sig, Waiting for Plan 9! *
 == JOAT for Hire: Anything, ==  #########  I do Naval Architecture, ##########
===+++ Anywhere, my price +++=== # Spacecraft Design, UNIX Systems Consulting #
 ==   gwh@ocf.berkeley.edu   ==  # RPG writing/development, and lots of other #
  ==   gwh@gnu.ai.mit.edu   ==   ## random stuff, of course.  I'm a JOAT 8-) ##

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End of SPACE Digest V13 #403
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