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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)."
Bouncy Castle INNNNN SPAAACE!
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.)
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?
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.
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"
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
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
I thought the same thing when I first glaced at the article... I thought to myself, Deuce Bigelow, Male Gigolo, In Space.... eeewwwwwww.
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.....
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.
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"
That's what she said!
(and now I have twins... Awe, who am I kidding, I'm reading and posting on slashdot)
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
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.
Do you want to talk about it?
Nae king! Nae laird! Nae yurrupiean pressedent! We willna be fooled again!
From a tank of compressed air. (Seriously, how is this even a question?)
Presumably they will, but the walls of a module of this type are pretty thick (think car tire, not party balloon), there's multiples layers, and additional micrometeorite and debris shielding on top of that.
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.
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.
Think six inches, not car tire.
And material stronger than kevlar, not vulcanized rubber.
"I do not agree with what you say, but I will defend to the death your right to say it"
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
As one who happens to be 6'4", I'll say that on Earth a 6 foot ceiling is very different from a 20 foot ceiling. I'm not normally claustrophobic, but every now and then I just like to have some space around me. Skylab was interesting, in that respect, including the open framework floors.
Never having been in microgravity I can't tell how I'd respond, if being in a space 6'x6'x tens of feet would be sufficient for me, when I'm capable of moving in any of those dimensions.
The living have better things to do than to continue hating the dead.
I've seen bicycle tires that have 90+ PSI with no problem and I have some automobile on my car (admittedly non-standard) that have a normal pressure rating of 70 PSI that were even able to maintain that pressure with "foreign objects" inside of the tire for a prolonged period of time (long enough to get it repaired without even changing the tire and just "filling up" the tire with air before driving a dozen miles to the tire store).