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NASA Awards Contract To Bigelow Aerospace For Inflatable ISS Module
cylonlover writes "NASA has announced that it has awarded a $17.8 million contract to Bigelow Aerospace to provide the International Space Station with an inflatable module. Details of the award will be discussed by NASA Deputy Administrator Lori Garver and Bigelow Aerospace President Robert Bigelow at a press conference on January 16 at the Bigelow Aerospace facilities in North Las Vegas. However, based on previous talks, it's likely that the module in question could be the Bigelow Expandable Activity Module (BEAM)."
Manwhore Enterprises?
Bouncy Castle INNNNN SPAAACE!
Bigelow got their tech from NASA, because NASA didn't want to pay to move it forward. So, Bigelow makes it usable, NASA buys it back.
they've had an inflatable module on orbit for something like 4 years - it's pretty well proven, and much cheaper to put into orbit than fixed-side vehicles. (And as for the idea that something might pop it, if debris is going to poke a hole in a vehicle at *orbital speeds*, it's going to go through kevlar just as easy as it's going to go through the metal the existing space station components are made of.)
So where do they get the air to inflate it?
they'd better have a puncture repair kit too
If you're thinking about the fragility of flexible walls, Wikipedia says:
Bigelow Aerospace anticipates that its inflatable modules will be more durable than rigid modules.[13] This is partially due to the company's use of several layers of vectran, a material twice as strong as kevlar, and also because, in theory, flexible walls should be able to sustain micrometeoroid impacts better than rigid walls. In ground-based testing, micrometeoroids capable of puncturing standard ISS module materials penetrated only about half-way through the Bigelow skin. Operations director Mike Gold commented that Bigelow modules also wouldn't suffer from the same local shattering problems likely with metallic modules. This could provide as much as 24 hours to remedy punctures in comparison to the more serious results of standard ISS skin micrometeoroid damage.
I'm curious about pressure though. In the vacuum of space, if it's inflated to human-habitable pressures, won't the pressure difference between inside and outside put an enormous strain on the fabric?
what could possibly go wrong
Plenty. It's when they get it up there and suddenly remember there's no air in space.
Alternatively, they could fill it with helium and float it up, but without a decent puncture repair kit one false move and it's a mars orbit in moments!
Won't be more than 15 PSI.
Which isn't that high - not even as high as a tire (35-40 PSI)
I don't doubt the science behind the concept, and your point about debris being able to puncture the exterior no matter what is a good one. I'm curious about the potential psychological impact of the module. Even if it's completely irrational (and the FA says non-rigid exteriors are better able to withstand a micrometeor), I can't help but feel that if I was up in the ISS, I'd want a solid metal wall, rather than an inflatable fabric one.
Having said that, being able to more than double the size, and presumably living space, of the ISS would probably do a great deal of good psychologically. Not to mention the fact that people who choose to go on missions to the ISS must have a certain amount of crazy to begin with, so probably wont care in the same way an ordinary mortal such as myself would.
The next question of course is how to get it up there? It's about 10x more than the maximum payload of either the Dragon or Soyuz rockets...
Laughter is the best medicine, except if you have a broken rib.
From Wiki. "The atmosphere on board the ISS is similar to the Earth's.Normal air pressure on the ISS is 101.3 kPa (14.7 psi);[139] the same as at sea level on Earth." http://en.wikipedia.org/wiki/International_Space_Station
Should be fine. Not too sure if would be ok 5-10m below sea; but it would really have gone wrong before that. So they may not build in any crushing force resistance at all.
Not Really. The atmospheric pressure is ~14psi. Duplicating it on the ground just blow somthing up a baloon to 28psi. Still relatively low pressure.
Someone please correct me, it I totally screwed that up.
This is 17 million for the study. More importantly, beam will NOT be 65 tonnes. Heck, we have nothing that can take it up since the days of the saturn V. It is a SMALL closet that will weigh under 7 tonnes.
I prefer the "u" in honour as it seems to be missing these days.
Mm, but a tyre has 15 PSI (1 standard atmosphere) on the outside to counteract the 35 PSI on the inside.
This'll have 15 PSI on the inside, close to zero on the outside.
But I guess (can anyone confirm) that the strain on the skin is proportional to internal pressure minus external pressure, so I take your point that we're not talking massive numbers here.
yeah that would be 28 psi absolute, or 14 psi gauge. Unless you were testing it about 30 ft under water, which would probably be a great idea for leak detection.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
And as for the idea that something might pop it, if debris is going to poke a hole in a vehicle at *orbital speeds*, it's going to go through kevlar just as easy as it's going to go through the metal the existing space station components are made of.
True, as far as poking goes, and microscopic holes are not cause of immediate catastrophic failure, but there are still differences in how different type materials perform. Debris particle tangentially scratching the surface of a module might rip inflatable one wide open.
Why would it be high pressure?
as below,,.. 15 PSI probably at most, It could be a lot less though, decrease the oxygen ppm by half and it can be 7 PSI, the pressure is not so important as maintaining the oxygen PPM as far as humans are concerned.
Note that the Genesis testbeds have been in orbit for years with no problems.
Admittedly, Genesis was only inflated to 10 psi or so, and the ISS is pressurized to 14.7psi. But 14.7 psi is, presumably, well within the design specs of the module, since it was originally designed to handle a standard atmosphere of internal pressure.
"I do not agree with what you say, but I will defend to the death your right to say it"
Nobody else mentioned vibration and oscillation? Not a huge problem if you're using as a passive warehouse but giant fans blowing life support air are going to make the thing kinda floppy all the time.
I think this would be an interesting science experiment, both the biology of "is a space sickness adjusted human vulnerable to wobbly walls" and the science experiment of repetitive strain failure modes of flex materials (the skin doesn't bend twice, once when made and once when inflated in space, it bends at say 1 Hz continuous while deployed if the structure wobbles. Also the economic experiment where if you have to go to expensive effort for vibration proof motors and all, vs the cost of just boosting a heavier traditional tin can.
There are also interesting impact and torque issues. So if you shove the middle of a wall with your shoulder (or worse) can it snap off an airlock 50 feet away, whereas unpressurized tin can would just bend?
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Won't be more than 15 PSI. Which isn't that high - not even as high as a tire (35-40 PSI)
Mm, but a tyre has 15 PSI (1 standard atmosphere) on the outside to counteract the 35 PSI on the inside.
Tire pressure measurements are relative, not absolute. So "35-40" PSI tire pressure means 35-40 PSI higher than atmospheric pressure
I'm curious about the potential psychological impact of the module
You went off on a materials science tangent, I'm gonna go on the impact of "lets put him in the rubber room" jokes. "I heard the next supply ship has straitjackets". I suppose latex pr0n jokes too.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
...Torg's team will be arriving shortly. Suggest you evacuate using the DFA.
Ok so it might be viable, but somehow i expect them having tons of trouble convince astronauts thats its safe...
There is no inflatable product on the market today that does not eventually develop a leak or burst. Air mattresses, tires, dolls...
I haven't thought of anything clever to put here, but then again most of you haven't either.
It could be a lot less though, decrease the oxygen ppm by half and it can be 7 PSI, the pressure is not so important as maintaining the oxygen PPM as far as humans are concerned.
See apollo 1 fire. In orbit a 4 psi ppO2 fire is just a 4 psi ppO2 fire, doesn't matter much. But on the ground they like to pump that dude up to 4 psi over ambient to test for leaks before launch, especially hatch leaks. So you traditionally end up in 20 psi ppO2 and the slightest spark and "woosh" which is pretty much a summary of how everyone got killed in Apollo 1. Now sea level air means you have a ppO2 regulator so you leak test by pumping up to 20 psi absolute, of which most of the extra pressure will be mostly harmless N2.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
There are lots of layers to avoid that.
As others said, the difference between earth pressure and space pressure really isn't that great. 15 PSI differential is about the same as your car tires, and there are inflatable boats in current use that sustain even more. Pressurized diving suits regularly sustain pressure many dozens of times greater than this.
To (likely mis)quote Futurama:
"We're going deep under the ocean, being subjected to thousands of atmospheres of pressure!"
"How much can the ship handle?"
"Well given that it's a spaceship, anywhere from zero to one."
Famous last words.....
Accepting your numbers as valid (they aren't - the 35 psi in your tires is relative to atmospheric pressure, not absolute), that means a pressure differential on this module of 15 psi, as opposed to the 20 psi pressure differential on the tire.
Do you see a lot of tires exploding due to the pressure differential where you live?
"I do not agree with what you say, but I will defend to the death your right to say it"
Who said these famous last words?
This structure is more resistant to micrometeorite impacts than the other ISS modules. The penetrate less and are made of well known materials. These are fabrics designed for their rip resistance, because of that they are used in ropes, rigging for ships and gunshot/stab resistant vests.
One of these units has already been in space for years for testing purposes.
Not much as this is proven technology that not only they but NASA was working on in the 60's. The simple fact is at orbital velocities, there is nothing thats really going to stop anything nasty from going through the sides of something, you have little further to look than some of the damage done to the shuttles and Mir by space debris.
"Slashdot, where telling the truth is overrated but lying is insightful."
As far as the repetitive strain failure goes, there have been two testbeds of the inflatable module in space for five or so years each, neither of which failed that way.
And given the pressure differential involved, I suspect that the walls would seem as rigid as steel - 15cm thick, supported by 14.7psi (yes, I'm mixing measurement systems shamelessly) internal pressure isn't going to allow much room for "wobbly walls"....
"I do not agree with what you say, but I will defend to the death your right to say it"
ISS modules are protected by aluminium shields. The meteorite will hit this shield, punch through it but disintegrate in the process so it won't penetrate the module wall. They could flat-pack a set of shields alongside the inflatable module for launch.
That's what she said!
(and now I have twins... Awe, who am I kidding, I'm reading and posting on slashdot)
This is a good step forward, and something that has been a long-time in coming. Good job Bigelow!
Good engineering really should win out, and this stuff really does seem to be just better.
Make the balloon a 2-layered affair with a few feet of air space. Then you fill that space with thousands of small floating balloons whose interiors are slightly sticky. Meteorite hits. Small balloons immediately travel to where the air is leaking out, burst, and plug the hole with a bunch of goopy rubber until someone (or some robot) can go outside once a month or so and put on maintenance patches.
Please do not read this sig. Thank you.
These fabrics are designed specifically to have good strain resistance under tension (which is how they'd be inflated in the near vaccum of space). It's hitting their design sweet spot.
Also FatPhil on SoylentNews, id 863
I believe it was the White Star Line.
The analogy to flat-pack furniture is spot on with what is happening here. This isn't just something that you "add water and watch it grow", it will be taking some assembly once the whole things is put up into orbit and in fact a sort of "flat-pack" system simply to squeeze everything into the payload faring. The main advantage of this style of module is that it ultimately has a whole bunch more volume, so station design can be more compact rather than having everything much more spread out.... as is the case with the rest of the ISS modules. There will be many service flights to simply put things into this module.... and they will be able to add other stuff on the outside.
You sort of miss the point though that the shielding is already part of the design of this system. The only difference is that it uses a fabric shielding rather than something metalic..... so why would the astronauts need to add more? If it becomes a problem, it can be repaired.
Bigelow didn't just invent this stuff out of the blue. This technology was originally developed by NASA and was called Transhab. It was tested extensively and has considerable amount of redundancy in the many layers incorporated into the design. In almost all respects it outperforms the rigid modules currently used in the ISS. The only reason that this isn't being used already is because funding for the project was cut and NASA sold the technology to Bigelow. In a way it was a fortuitous thing because now they can get the technology they already wanted, and trust, without the cost of continued development. It has been commoditized (as much as space stuff can be a commodity.)
They did not have lots of layers.
They had many compartments, which do not address a large continuous tear.
Good effort though.
The design is essentially the recycling of old NASA concepts:
http://en.wikipedia.org/wiki/TransHab
The multi-layer design is highly effectively again MMOD impacts, better than most of the shielding currently on ISS.
The way I heard it, the TransHab (inflatable module) had some really serious enemies in Congress. That is, enemies to the tune that the NASA budget was written to explicitly forbid any money for TransHab development. So NASA sold what they had to Bigelow, since they were legally forbidden to do anything else with it. (Just checked Wikipedia, and there is at least some level of confirmation for this.)
Bigelow has 2 TransHab-based test articles in orbit. Last I heard, they were planning their own "Space Hotel." I wonder what they'd charge for "Hundred Mile High" certificates, apart from the launch and on-orbit fees.
Interestingly, everything I'd see on TransHab had the floors perpendicular to the axis. The photos in TFA have the floors parallel to the axis.
The living have better things to do than to continue hating the dead.
yeah that would be 28 psi absolute, or 14 psi gauge. Unless you were testing it about 30 ft under water, which would probably be a great idea for leak detection.
Which is one of the reasons why Bigelow Aerospace has one of the largest swimming pools in Las Vegas (and that is saying a whole lot by itself). They intend to do not only underwater testing of these modules (or at least the design) before it goes up, but even provide an opportunity for astronauts to get up close and used to servicing the vehicle here on the Earth in a "neutral buoyancy simulator" (using scuba tanks to simulate EVAs).
psychology....
Have you seen any of the videos sent back from the ISS? From what the videos show, that thing is basically a maze of tunnels. There are a few (tiny) "rooms" off to the side, the cupola being the most notable and most different. (and biggest?) What's the long-term psychological impact of living in a "warren", and how great would the benefit be of having some real rooms?
The living have better things to do than to continue hating the dead.
There is nothing currently flying that has the payload capacity for this:
Delta IV Heavy can do about 23,000 kg
Arianne 5 can do about 21,000 kg
Shuttle's cargo capacity was around 24,000 kg, so it would have been useless too.
The planned Falcon Heavy is only for 55,000 kg or so, so still short.
The planned NASA space launch system calls for this type of capability.
Anyone got a spare Saturn V? That'll do it.
But I guess (can anyone confirm) that the strain on the skin is proportional to internal pressure minus external pressure
Yes, strain and load are proportional to the pressure (force = pressure * area). The difficulty comes in due to the area being proportional to the square of the radius. This is why tires can handle 35-65 psi and scuba tanks are able to hold 3000 psi while commercial aircraft can be damaged by the relatively small (~8-9psi) cabin pressures. Aloha Airlines Flight 243 is one example and there are several more here.
The loads the skin of these Bigelow Aerospace modules must carry are very large and it isn't a trivial engineering problem to make something that is strong enough to handle the pressure but light enough to launch into space.
Assuming 14psi, the axial pressure loads in the two larger BA modules are:
BA330, 22ft diameter - 760,000 lbs
BA2100, 41ft diameter - 2.7 million lbs
Knowledge Brings Fear
On earth 6 foot ceiling is not all that much different than a 20-foot ceiling, because you arent going to use much of that space above 6 feet. But in micro-gravity you any of the six walls becomes a floor, thereby allowing you to use the entire volume. Less claustophobic in that case.
I can't help but feel that if I was up in the ISS, I'd want a solid metal wall, rather than an inflatable fabric one.
Agreed, though my (irrational) reasoning regards putting a sealed, pressurized object into a vacuum. Can it be done? Of course! Would I feel just as nervous about being in a space suit? While I cannot say for certain, I do not think so. But for some reason, thinking about being inside a balloon that isn't human-shaped leaves me feeling a little uneasy.
"I'm not sure I like the fugnutish tone you used in your post!" -RogL (608926)-
No, you blow it up to 14 PSI. They blow it up much higher pressure for leak tests because the fabric can take A LOT more than 1 atmosphere.
Learn how your pressure gauge works. Why do you should check your tire pressure when you go from ground level up into the high mountains (or vice-versa)? Pressure is *ALWAYS* relative, and not just absolute but partial pressure. Partial pressure is why you can breathe.
http://en.wikipedia.org/wiki/Partial_pressure
People live in tents with little problem, and the walls of these modules are rather high tech no matter what. Plus, when you fill it up to something resembling sea level(14.7 psi), you're going to have a structure that's about as stiff as the thin aluminum walls of a solid structure. They're almost certainly stronger - we have much better tensile strength materials than flexural strength. A big tube of aluminum will end up flexing on it's own, probably more than the inflated module.
For a real world example, many car tires are only inflated to 30 psi. So consider how stiff that tire is at less than 10% more than the difference between vacuum and the module. Pay attention to the thinner wall - not the tread, of course.
I don't read AC A human right
Given how cheaply most gauges are built, I'd simply say 'put the gauge markings assuming that the outside is at 14.7 PSI, sea level'.
But them being relative makes sense. You'd fill your vehicle up in Denver(mile high city) with a little less absolute pressure than in Florida, but that wouldn't matter much as there would be less air pressure trying to collapse them.
Also, if a rubber tire can withstand 90+ PSI*, I have no problems believing that an advanced hybrid using fibers tougher than kevlar can hold 14.7 PSI without problem.
*Going by explode point, not daily use, though I know of rubber tires
I don't read AC A human right
It's also likely they'll have stop-leak infused between the layers of the structural fabric laminate. So you don't have to worry too much if something small does manage to poke a hole in it. Self sealing tech has been around for quite a while anyways, so there's not much reason why it shouldn't work in this particular application.
It won't be like Bigelow BA 2100, they're looking for an ISS module, not another ISS. Other sources say the module will only be about 1 ton.
I imagine there are some astronauts down the pipeline jumping for joy at the possibility. Skylab was the only station with a decent amount of internal space, and that burnt up 30 years ago. While I doubt this will be one of the larger Bigelow components (BA 2100, 4 DECKS! @65,000 kg) I bet it'll add a significant amount of space to the station. Hopefully they don't have any trouble funding a launch vehicle for it, ~$18 million is chump change for increasing the stations livable area by at least 35%.
I think the problem is that some people (myself included) thought that the proper way to compare it is interior pressure / exterior pressure. But from the comments, it sounds like interior pressure - exterior pressure is the correct way.
"I'm not sure I like the fugnutish tone you used in your post!" -RogL (608926)-
Remember, in space, no one can hear you leak.
I was looking around, it turns out that the inflatables produced by Bigelow have a 15 cm thick skin, and while I'm not finding any source, I seem to remember them inflating one up to 50+ PSI on the ground as part of some test and not having a problem.
I don't read AC A human right
You're right, total pressure depends on the surface area, but when it comes to containing gas pressure, size matters less than you think.
You could make an aircraft that could hold the pressure of a scuba tank; but it'd be too heavy. A scuba tank is a LOT heavier for the surface area than a plane, and a plane needs to withstand many different stresses than the tank.
If you're making a tank, small or large the gauge of steel needed for the pressure remains about the same for the given pressure. Larger tanks will need more support to withstand the stress of gravity - which isn't perfectly proportional, but that's not a problem in space.
I don't read AC A human right
So to all you Obama haters, let it be known, here is yet another example of how Obama gets things done cheap and well.
Obama is the most fiscally responsible president we've had in decades.
Too bad he is paired up with the worst Congress in our country's history.
(at least the House is).
"I can't help but feel that if I was up in the ISS, I'd want a solid metal wall, rather than an inflatable fabric one."
I can't speak for any astronauts that might encounter this, but if it was me I would prefer the walls that are around 6" thick rather than a steel can that is 1/4 inch thick.
These people ride rockets tinto orbit at 17,000 mph and come back in something which burns itself up to save their skins, all dependent on incredibly precise control, and you think they would waste any brain power to worry about the module popping from decompression?
Astronauts are probably the most anal-lytic of all adventurers, calculating everything to a fare-thee-well, practicing their missions for years in swim tanks to get every last detail down pat. The last thing they are going to do is become emotional about such an easily proved design.
Infuriate left and right
The situation is not quite as bad as you present, because we don't actualy care about the axial loads, we care about the skin stresses. Yes, pressure increases linearly with the amount of surface area (i.e. with the square of linear dimension), but the stress we care about is distributed along the skin cross section, which is directly proportional to the linear dimension.
For example lets think of "ring" of wall that makes up the middle of a cylindrical chamber. Air pressure is exerting a radial force outwards in all directions, while the tensile strength keeping the ring from stretching/tearing is oriented circumferentially, with the material fibers acting like thousands of tiny rope rings. Double the diameter of the ring and you double the surface area, the pressure, and the the force exerted by each of those tiny ropes to keep it from stretching. On the other hand double the length, and there's no net change. You still have twice the force being contained, but now you also have twice as many ropes, so the force on each one is unchanged. As for the axial forces, those change with the square of diameter, but not at all with length. And the number of lengthwise "ropes" also increases linearly with diameter, so each doubling of diameter again only doubles the stress on each strand.
Obviously there's still an upper limit, but the picture is much rosier:
22ft diameter = stress of ~34,000 lbs/foot
41 ft diameter = stress of ~65,000 lbs/foot
There's also a really simple solution: every time you double the diameter, (which doubles the stress) also double the thickness of the fabric, (which doubles the number of fibers carrying that stress). When you consider that working volume is proportional to diameter cubed, and amount of fabric is proportional to surface area (diameter squared) times a thickness that increases linearly with diameter, what you really end up with is that the amount of material scales linearly with enclosed volume, not such a bad thing at all.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
http://www.youtube.com/watch?v=7qZX2yI39A8
no joke.
Even if it's completely irrational (and the FA says non-rigid exteriors are better able to withstand a micrometeor), I can't help but feel that if I was up in the ISS, I'd want a solid metal wall, rather than an inflatable fabric one.
And? Sounds like the appropriate choice would be to get over your belief than to compromise your safety.
The next question of course is how to get it up there? It's about 10x more than the maximum payload of either the Dragon or Soyuz rockets...
It's inflatable. It's not "10x" more when it's being launched.
Not necessarily. Pressure itself is not relative, there's a very definite zero-point in hard vacuum. Most pressure gauges are relative, because most of the reasons we care about pressure likewise depend on pressure differentials. You can however purchase pressure gauges that measure absolute pressure, though they tend to be much more expensive and the applications are limited. One that springs to mind is maintaining breathing gas - humans need a certain partial pressure range of oxygen to survive. Too little and we start suffering brain damage from oxygen deprivation, too much and we start suffering various oxidation-related damage (typically a slower process, but still quite dangerous). In both cases it's the absolute partial pressure we care about. Whether we're breathing pure O2 at 1/5 atm or a 1/25 O2 mix at 5atm we're good, at least as far as O2 is concerned.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Other way around, *double* the O2 ppm and you can lower the pressure by half, since the partial pressure of O2 will then remain the same. In fact with a pure O2 environment you could cut the pressure to 1/5 atm (3psi) while still maintaining sea-level O2 pressure. You could possibly drop it even lower, most people can readily adapt to a 1.5psi partial pressure (~ 6000m), and at least some can adapt to 1psi (~9000m ~= peak of Mount Everest, which has been climbed without extra O2). I don't know how well we'd adapt to such low absolute pressures though.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Right. Think of it like forces on a wagon - if you have two people pulling the same amount in in opposite directions the net force is zero and nothing happens. If one of them pulls with 1lb more force the net force is now 1lb, and the wagon will move as though there were only a single 1lb force acting on it, the rest of the force cancels out whether its 2lb or 2000.
Pressure is almost exactly the same thing, except you're talking about force-per-area - matching pressure cancels out, leaving the difference to be taken up by the structure maintaining it.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
You mean the same way your car tires are all wobbly? Or a firmly inflated balloon? Bouncy castles and such are wobbly because they're inflated to low pressures - inflate them to two atmospheres and they'd be practically rigid. Add in the fact that the module material likely has *very* little stretch and you'll get minimal flex.
Say your module has a 20ft diameter ~= 600 square feet cross section. Multiply that by 15psi and you get 1.3 million pounds of force keeping the opposite ends apart. There's no way your air circulation system is going to muster those sorts of forces and cause wobble. As for vibration, sure, every single part of the space station is continuously vibrating, for that matter so is every structure on Earth. And generally speaking a flexible material will survive vibration and much better than a rigid one, that's one of the reasons long suspension bridges are so much more common than arched ones - the longer the bridge the greater the unavoidable vibrations, and flexing allows the energy to be dissipated harmlessly rather than gradually deforming or breaking rigid components.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Psychology revolves around what you see and feel. In this case, an astronaut floating into a Bigelow module attached to the ISS will be feeling an outer skin that feels exactly as rigid as the walls of the rest of the station. The material the module is made of is so strong and so thick and held in place so rigidly by air pressure that it feels as strong as steel to the touch. We know this because of inflated test modules on Earth. Inflate it to an equivalent pressure to what it will be on orbit, and that's what it feels like. It feels very very solid. The fact that the physics and projectile testing says it's actually even stronger than it feels is a bonus.
I've lived in Cusco, Peru (11,200 feet/3400 meters), and after a week or two adjusting it's quite comfortable if you're not doing strenuous labor. After a month riding a bicycle or carrying a heavy load is still a bit more difficult than at sea level, but not dramatically so. There is no real reason to maintain a space station at sea level atmospheric pressure, except that the launch pad and training centers are at sea level so astronauts are used to it. Move your facilities to the Ecuadorian Andes (which has other advantages anyway) and the habitat could change its standard pressure to that of Quito (9,350 feet/2800 meters).
"Think about how stupid the average person is. Now, realise that half of them are dumber than that." - George Carlin
In fact, this might destroy ASI's work on the cans. It always drove me up a wall that we removed competition on the module constructions. BUT, each one of those cans cost something like 200 million on up.
OTOH, if is 17 million for this small unit, it will be a major paradigm shift. The reason is that BEAM was SUPPOSED to include CBM or LIDS on each side. If they can do all of this for 17 million and all that is needed is to extend the metal core, and increase the size of the outer fabric, well, that means that a BA 330 can be done for under 50 million. Easy.
It also means that for less money than what ASI charge just for manufacturing their cans, BA and SpaceX can put a module that is 3-6x larger in volume. That really is incredible.
I prefer the "u" in honour as it seems to be missing these days.
They've been posting the same job openings for designers, engineers and model makers for the past 5 years.
Are they finally gonna hire people?