Space Tourist Spacesuits

Christopher M. Jones wrote:
Henry Spencer wrote:
In article ,
Earl Colby Pottinger wrote:

Mass also is an issue. A hundred-kilogram suit is fine for LEO...
...less than optimal for Lunar operations, and not at all for Mars, what
with that pesky "gravity" pulling at it.

But that is only 33 Kilos in wieght. That does not seem to be an
unreasonable wieght for a healthy adult to carry about. Yes, lighter would
better, but 100 Kilos mass should not be a show stopper.

33 kilos is one hell of a lot to carry for prolonged activity, even before
you figure in the added complications like stiff joints. This *is* a show
stopper for major surface operations.

It's incredibly borderline, at the least. On the one hand
there are folks who traipse around uneven ground for hours
a day with that much weight strapped on their backs. On
the other hand, those folks tend to fall in a very, very
narrow band of individuals in peak physical condition.

Most people moving over uneven ground tend to prefer to carry
around somewhere around 20 kgs, and pay quite a bit extra to
be able to carry around less than they would otherwise.

And that's not good for a variety of reasons. The folks
who have the education and experience (scientists, test
pilots, etc.) to be the best professional astronauts tend to
be older and past their peak physical condition. The same
applies to the folks who tend to have the money to buy
multi-million dollar trips to Mars.

However, if you look at the various factors, it doesn't
necessarily look too far out of the question to use 100 kg
suits on Mars. Factor in body mass and then figure the
total weight, adjusting for Martian gravity, and you end up
very near the body weight on Earth. With a good support
system that puts the weight on the hips and doesn't overly
unbalance the walker, it might just be feasible for
otherwise ordinary individuals in merely good physical
condition to work productively on Mars.

A 100kg suit will have secondary effects you are not thinking
of that still apply even in reduced (or no) gravity like
momentum. 100kg suits are most probably always a bad idea, except
possibly if they come with powered exoskleton or similar.

And then you might just as well make light, single use suites that
last a limited time - and have people simply always drive around in
a car.

--
Sander

+++ Out of cheese error +++

"Christopher" wrote in message
...
On 22 Feb 2005 04:47:35 -0800, wrote:

Considering that many space tourists will be those that enjoy
risk-taking, I can easily imagine a space hotel offering (with
iron-clad waiver required!) vacuum jumping. That is, clients, without
spacesuits, will be poised in one fast-opening airlock, will leap
through the vacuum across a gap of a few meters into a fast-closing,
fast-pressurizing airlock. Even with a waiver, I expect the hotel
would insist on the client being tethered so they can be quickly hauled
across if necessary. Talk about 'up close and personal'!

Only an idiot would try it.

In other words, there's a market!





Christopher
++++++++++++
"The best way to keep one's word
is never to give it."

Napoleon Bonaparte

Rand Simberg wrote:
On 22 Feb 2005 04:47:35 -0800, in a place far, far away,
made the phosphor on my monitor glow in such a way
as to indicate that:

I can easily imagine a space hotel offering (with
iron-clad waiver required!) vacuum jumping.

Unfortunately, there's no such thing as an "iron-clad waiver."

There are businesses that take clients into risky situations. I
presume they require waivers and also carry lots of liability
insurance.

On 23 Feb 2005 04:42:03 -0800, in a place far, far away,
made the phosphor on my monitor glow in such a way
as to indicate that:

I can easily imagine a space hotel offering (with
iron-clad waiver required!) vacuum jumping.

Unfortunately, there's no such thing as an "iron-clad waiver."

There are businesses that take clients into risky situations. I
presume they require waivers and also carry lots of liability
insurance.

They do, but no waiver is "iron clad." It discourages lawsuits, but
doesn't prevent them.

(Henry Spencer) wrote:

:In article ,
:Earl Colby Pottinger wrote:
: Mass also is an issue. A hundred-kilogram suit is fine for LEO...
: ...less than optimal for Lunar operations, and not at all for Mars, what
: with that pesky "gravity" pulling at it.
:
:But that is only 33 Kilos in wieght. That does not seem to be an
:unreasonable wieght for a healthy adult to carry about. Yes, lighter would
:better, but 100 Kilos mass should not be a show stopper.
:
:33 kilos is one hell of a lot to carry for prolonged activity, even before
:you figure in the added complications like stiff joints. This *is* a show
:stopper for major surface operations.

Combat troops routinely cover significant distances over several days
while carrying this sort of load. If the load-carrying gear is well
designed and the weight is relatively evenly distributed, 33 kilos of
burden is hardly a show stopper.

--
"When you enter a room full of armed men, shoot the first
person who makes a move, hostile or otherwise. He has
started to think and is therefore dangerous..."
-- Colonel Paddy Mayne, co-founder of the SAS

"Christopher M. Jones" wrote:
It's incredibly borderline, at the least. On the one hand
there are folks who traipse around uneven ground for hours
a day with that much weight strapped on their backs. On
the other hand, those folks tend to fall in a very, very
narrow band of individuals in peak physical condition.
And that's not good for a variety of reasons. The folks
who have the education and experience (scientists, test
pilots, etc.) to be the best professional astronauts tend to
be older and past their peak physical condition.

Nit: The folks we have commonly recruited to be astronauts fall into
the past their physical prime. It's not a certainty of the universe
that the type of folks recruited in the past mark a forever and graven
in stone requirement.

D.
--
Touch-twice life. Eat. Drink. Laugh.

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL

Fred J. McCall wrote:
(Henry Spencer) wrote:

:In article ,
:Earl Colby Pottinger wrote:
: Mass also is an issue. A hundred-kilogram suit is fine for
LEO...
: ...less than optimal for Lunar operations, and not at all for
Mars, what
: with that pesky "gravity" pulling at it.
:
:But that is only 33 Kilos in wieght. That does not seem to be an
:unreasonable wieght for a healthy adult to carry about. Yes,
lighter would
:better, but 100 Kilos mass should not be a show stopper.
:
:33 kilos is one hell of a lot to carry for prolonged activity, even
before
:you figure in the added complications like stiff joints. This *is*
a show
:stopper for major surface operations.

Combat troops routinely cover significant distances over several days
while carrying this sort of load. If the load-carrying gear is well
designed and the weight is relatively evenly distributed, 33 kilos of
burden is hardly a show stopper.

--

That's pack weight, and you take it off whenever you can. 33 Kilos on
your hips and shoulders is *easier* to handle than the same amount
spread over your whole body. Consider the difference between a pair of
two kg. ankle weights and the same weight in your backpack.

Consider medieval armor for the whole body. The designers wanted it to
be as thick as practical, since the thicker it was, the more protection
it offered. Almost all surviving suits for battlefield use were less
than 33 kilos, even though their owners typically expected to ride
horses rather than hiking over rough terrain.

Will McLean

kert wrote:
wrote:

I don't think space tourists should be allowed to spacewalk
anyway.

For some, the opprotunity to do so, will be a large part of the
reason for going.

And, its a nice place for providers to charge hefty extra

-kert

Definately an extra charge. While tourists are in the station, they
won't need to be under as constant direct supervision, but out on a
space walk - tethered - they will need at least two full time staff
supporting them, and probably ground crew monitoring them to boot. I'm
thinking in the 1 million dollar range for a space walk.

The space walk suits would probably be in small, medium or large, and
not be the property of the tourist, and reused for other tourists.

Moon tourists would probably have to buy their own suit, and whether
they would want to keep it around or not after would be their choice.
Of course, the freight costs to ship it back to earth would have to be
considered also. Lots of stuff shipped into space for use there would
have to be a huge extra charge to bring back to earth. I'm also
thinking there would be a clause that if they die in space, the body
doesn't get returned unless they pay a premium. You, too, can be part
of the agriculture of the space station in perpetuity. The molecules
of your body can help feed astronauts forever. . .

Harmon Everett wrote:

kert wrote:
wrote:

I don't think space tourists should be allowed to spacewalk
anyway.

For some, the opprotunity to do so, will be a large part of the
reason for going.

And, its a nice place for providers to charge hefty extra

-kert

Definately an extra charge. While tourists are in the station, they
won't need to be under as constant direct supervision, but out on a
space walk - tethered - they will need at least two full time staff
supporting them, and probably ground crew monitoring them to boot. I'm
thinking in the 1 million dollar range for a space walk.

Which is total madness. You are just setting yourself up to be an
easy target to be outcompeted.

[snip ... and then you went even more madder]

--
Sander

+++ Out of cheese error +++

Derek Lyons wrote:
"Christopher M. Jones" wrote:

It's incredibly borderline, at the least. On the one hand
there are folks who traipse around uneven ground for hours
a day with that much weight strapped on their backs. On
the other hand, those folks tend to fall in a very, very
narrow band of individuals in peak physical condition.
And that's not good for a variety of reasons. The folks
who have the education and experience (scientists, test
pilots, etc.) to be the best professional astronauts tend to
be older and past their peak physical condition.

Nit: The folks we have commonly recruited to be astronauts fall into
the past their physical prime. It's not a certainty of the universe
that the type of folks recruited in the past mark a forever and graven
in stone requirement.

I specifically mentioned the reasons why this practice
exists. It is not arbitrary, it happens because the
folks with the most education and experience tend to be
of an age where they are past their physical peak.
This is as true for fighter aces and test pilots as it
is for engineers and scientists.

There are certainly very, very many qualified folks who
are in their physical prime who could do the job
satisfactorily, or better. However, it is still
important to recognize that placing this sort of
contraint on the selection process will necessary
narrow your pool of talent substantially and you will
almost certainly end up with a group of folks who are
not the best for the task. Again, you will probably
still have plenty of folks who can do it well enough.
But that cost must still be kept in mind. If you
have to spend a sizeable fraction of your development
budget to reduce the weight of the suit in order to
open up the selection criteria to include the "sweet
spot" of folks with experience and education, then
it's probably worth that cost.

Additionally, as I noted the issue is not merely
professional astronauts, as the subject of the thread
is tourist spacesuits. As I pointed out, the same
sorts of criteria operate here as well. The people
with the free time and money to afford something
that might cost millions or hundreds of thousands of
dollars and take months or years tend not to be at
their physical peak either. They may be willing to
get into shape, but they will not be physically
capable of reaching the abilities of young men in
their 20s, period. If your systems don't allow those
folks to get the most out of their Mars trips then
you almost certainly want to pour a lot of R&D money
into developing better systems. As otherwise you
are cutting off a huge portion of your likely
customer base, which is never smart if you can afford
not to.