Path: utzoo!attcan!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!nrl-cmf!cmcl2!phri!dasys1!tneff
From: tneff@dasys1.UUCP (Tom Neff)
Newsgroups: sci.space.shuttle
Subject: GRiD computer onboard Orbiter
Summary: MS-DOS laptop flies every mission
Message-ID: <6880@dasys1.UUCP>
Date: 9 Oct 88 22:06:57 GMT
Reply-To: tneff@dasys1.UUCP (Tom Neff)
Distribution: na
Organization: Independent Users Guild
Lines: 43

We've been talking about the 5 general purpose computers that run the
Orbiter, how they're rather antiquated etc., and how other payload
specific computers "hop a ride" now and then for non-critical
applications.  I just thought I'd mention that there is a "sixth
computer" that does fly every mission, in the form of a "Compass"
laptop from GRiD Systems of Mountain View CA.  (Disclaimer: I have no
affiliation with GRiD except as a customer -- we use their laptops for
our salesmen in the field.  This isn't meant to be an ad or a plug,
just a bit of trivia.)

If you remember the in-flight press conference or have a tape of it,
you can see the Compass velcro'd down (surprisingly loosely!) atop
the middeck storage rack, behind the crew as they face into the camera.
It's got a black magnesium case in a clamshell configuration with a
flip-up EL display.

What do they run on it?  Well one thing is that graphic orbit tracking
display program people have been passing around "from NASA."  I guess
that's the only way people working in the middeck can keep up on their
whereabouts.  There were also plans to use it for a live electronic
BBS-style conference from on orbit... guess what mission.  :-(   I gave
a little help to one of the guys programming the laptop at the time,
getting a VT100 emulator to run on it, but I have no idea what's
happened since then.  (It would still be a nice idea.)

Oh yeah, why GRiD you ask?  Simple, they were (and may still be) the
only laptop maker with a radiation hardened version that passes
MILSPEC.  The Army is supposedly a big customer too.  I guess even
though the laptop doesn't have any life and death responsibilities like
controlling the flaps and SSMEs, it would still be an expensive pain in
the *** to get it zapped after repeated flights and mess up a middeck
experiment or something.

My GRiD salesman told me the only customization they had to perform was
on the power supply, so it could run straight off the Shuttle's
appliance bus.  There were no fans to begin with, it cools via
convection...  this might be less effective on orbit, but the MILSPEC
parts are hardier.

-- 
Tom Neff			UUCP: ...!cmcl2!phri!dasys1!tneff
	"None of your toys	CIS: 76556,2536	       MCI: TNEFF
	 will function..."	GEnie: TOMNEFF	       BIX: t.neff (no kidding)