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Bigelow Aerospace Launch!


Mazon Del
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17 minutes ago, Veeltch said:

How much cheaper the expandable modules are compared to the standard, rigid ones? Could it mean lowering the costs of modules/space stations if the tests are successful?

It's mainly lower launch costs and higher payload due to the lighter walls. It's not really much cheaper otherwise, i think.

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Really the big boon for it is the possibility of launching modules with very high volume, without having a similarly wide rocket. You can of course have fairings wider than the diameter of the rocket, but there is only so much you can do with that before it starts causing you issues. As increasing the diameter of the rocket tends to dramatically increase the costs of that rocket, it's a pretty decent way to pack big rooms onto smaller rockets.

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I don't see why they would be cheaper. If anything, they are more complex and require quite a lot of orbital work.

Their advantage is that they offer more habitable volume, which is a "nice to have" feature, but not a key enabler for anything. In other words, it's probably not worth the extra cost or work.

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Just now, Nibb31 said:

I don't see why they would be cheaper. If anything, they are more complex and require quite a lot of orbital work.

Their advantage is that they offer more habitable volume, which is a "nice to have" feature, but not a key enabler for anything. In other words, it's probably not worth the extra cost or work.

It is if you need deep space HABs, where more than ever, every gram counts.

I think it's the most logical upgrade path, being lighter and more resilient to MMOD, so it's worth the extra R+D costs, but not as great as people often think.

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5 hours ago, Mazon Del said:

As increasing the diameter of the rocket tends to dramatically increase the costs of that rocket, it's a pretty decent way to pack big rooms onto smaller rockets.

The problem is, big rooms aren't any more useful than small rooms - it's the stuff in the room that makes it useful.   All that stuff still has to get up there and be installed somehow.

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Inflatable modules are (supposed to be) lighter and compact when stowed - you can send a spacious module on a small launcher, which saves you a ton of money. On the other hand, their walls made of multi-layered fabrics and resins and other stuff do not sound cheap at all to me.

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46 minutes ago, Scotius said:

Inflatable modules are (supposed to be) lighter and compact when stowed - you can send a spacious module on a small launcher, which saves you a ton of money. On the other hand, their walls made of multi-layered fabrics and resins and other stuff do not sound cheap at all to me.

Inflatables use the same stuff as on the normal aluminum cases that protects the aluminum- it realy should not be more than 25% more expensive, which should be offset by the smaller launcher, and the increased simplicity of the space station by using less modules.

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Since it's pretty much the same material, but for a larger volume, there is no reason for a Bigelow module to be lighter. It also has to include the inflation equipment. 

Launchers are mostly defined by payload mass, not volume, so you don't save any money. You don't need (or even want) wide open areas on a spacecraft. They just make it harder to move around in (see Skylab). Volume is only useful if you have equipment to put in it and you still have to send up all the equipment to fill that space.

Having an inflatable volume simply isn't that valuable. As I said, it might be a nice to have feature, but it's not a game changer.

Edited by Nibb31
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Inflatables would be much more valuable if we have a good ISRU capability. An inflatable water tank can carry more water than a fixed tank of the same weight, so if there's a source of water up there, launching an ISRU+inflatable tank combo would be a smarter move than an ISRU+fixed tank combo.

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39 minutes ago, Nibb31 said:

Since it's pretty much the same material, but for a larger volume, there is no reason for a Bigelow module to be lighter. It also has to include the inflation equipment. 

Launchers are mostly defined by payload mass, not volume, so you don't save any money. You don't need (or even want) wide open areas on a spacecraft. They just make it harder to move around in (see Skylab). Volume is only useful if you have equipment to put in it and you still have to send up all the equipment to fill that space.

Having an inflatable volume simply isn't that valuable. As I said, it might be a nice to have feature, but it's not a game changer.

But the wall mass is a lot lower.

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30 minutes ago, kerbiloid said:

Deflated balloon images?q=tbn:ANd9GcSqUvK9kduV1a54w0oXvD4 + Soda syphon with a gas cylinder images?q=tbn:ANd9GcSzSb9D68sMtbFbidXK_br

+ Caterpillar images?q=tbn:ANd9GcTFmMpU3LnyRLguPSMR9-- + Rubbed leaves images?q=tbn:ANd9GcSrkLSaQXM8JBsQvS0h7Ce + Superglue images?q=tbn:ANd9GcSgXqxke0eh354Ai7WgFyE

=

3d-printed Vegan-Friendly Inflatable Space Cocoon Habitat

Light-Powered-By-Silk-Cocoons.jpgcocoon1.jpg

 

Lolwut?

Wouldn't that be too weak to offer enough protection?

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19 minutes ago, fredinno said:

Lolwut?

Rather to telescopic mechanical construction with soft walls, expanding just +25% or so (so-called "inflatable module"), this is the true inflatable module, occupying just a bag on launch.
With just one launch you would create a whole colony of cocoons modular orbital station.

27 minutes ago, fredinno said:

Wouldn't that be too weak to offer enough protection?

Just use more superglue. It's dense and can be easily delivered.

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12 minutes ago, kerbiloid said:

Rather to telescopic mechanical construction with soft walls, expanding just +25% or so (so-called "inflatable module"), this is the true inflatable module, occupying just a bag on launch.
With just one launch you would create a whole colony of cocoons modular orbital station.

Just use more superglue. It's dense and can be easily delivered.

You can still make inflatables without any ridgid component- the BA-330 has it so that it can store equipment and the station in a single launch.

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1 hour ago, fredinno said:

But the wall mass is a lot lower.

Why would it be ? It's multiple layers of various materials, bladders, insulation, just like a conventional pressure hull. The walls are somewhat flexible, but they are much thicker. The material is less dense, but if it offers the same protection against MMODs and radiation, then the actual mass/area is likely similar.

But then because the inflated volume is much larger, so is the surface area, and consequently the mass.

Wikipedia says this

Compared to their own weight, expandable modules offer more living space than traditional rigid modules. For example, the pressurised volume of a 20-ton BA 330 module is 330 m3, compared to 106 m3 of the 15 ton ISS Destiny module. Thus BA 330 offers 210% more habitable space, with an increase of only 33% in mass.

That means that basically, you get more empty space with 33% less actual equipment, which is rather pointless. The problem is that Destiny's 15 tons included several tons of experiment equipment already, so the difference is actually more than 33%.

Basically, you're going to need at least 2 more supply and outfitting flights to actually fill up the space inside a BA330, whereas launching 3 Destiny modules gets you the same volume and much more equipment. 

Edited by Nibb31
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Instead of a corridor surrounded by built-in closets with equipment (which are themselves a thick wall between the living space and the strong hull) and equipment nailed to the hull itself — as in traditional "hard" module,
an inflatable module with the same equipment adds thick soft walls and ability to walk around the closets. Why a 2ft (or how many) thick soft wall would be lighter than a tin can of traditional hull?

 

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2 hours ago, kerbiloid said:

Instead of a corridor surrounded by built-in closets with equipment (which are themselves a thick wall between the living space and the strong hull) and equipment nailed to the hull itself — as in traditional "hard" module,
an inflatable module with the same equipment adds thick soft walls and ability to walk around the closets. Why a 2ft (or how many) thick soft wall would be lighter than a tin can of traditional hull?

 

It's actually 16 inches...

2 hours ago, Nibb31 said:

Why would it be ? It's multiple layers of various materials, bladders, insulation, just like a conventional pressure hull. The walls are somewhat flexible, but they are much thicker. The material is less dense, but if it offers the same protection against MMODs and radiation, then the actual mass/area is likely similar.

But then because the inflated volume is much larger, so is the surface area, and consequently the mass.

Wikipedia says this

Compared to their own weight, expandable modules offer more living space than traditional rigid modules. For example, the pressurised volume of a 20-ton BA 330 module is 330 m3, compared to 106 m3 of the 15 ton ISS Destiny module. Thus BA 330 offers 210% more habitable space, with an increase of only 33% in mass.

That means that basically, you get more empty space with 33% less actual equipment, which is rather pointless. The problem is that Destiny's 15 tons included several tons of experiment equipment already, so the difference is actually more than 33%.

Basically, you're going to need at least 2 more supply and outfitting flights to actually fill up the space inside a BA330, whereas launching 3 Destiny modules gets you the same volume and much more equipment. 

It actually offers better radiation protection (it doesn't have the cosmic radiation splitting effect of aluminum) and MMOD protection than aluminum walls.

Also, you only need one supply and outfitting flight- the one carrying the first crew to put everything in place- the reason the BA-330/Transhab have aluminum walls in the center is for this exact purpose- to hold the equipment needed in it before launch. Here is a calculator that you can calculatre Transhab masses with: http://www.projectrho.com/public_html/rocket/transhabcalc.php

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You need a cargo flight (probably several ones even) to bring up the equipment that didn't fit inside the deflated module. The inflatable module is heavier than an empty ISS module. Whereas the ISS module is pre-equipped on the ground, the BA330 goes up with only some of its equipment. It also needs to carry a whole stack of internal walls, floors, wiring, railing, plumbing, etc... that need to be installed after the inflation. That's a lot of assembly work for the crew before it can be operational, which probably requires at least one separate dedicated manned mission, so you need at least 3 launches before the hab is operational.

Also, an ISS-type module with equipment racks on the outer walls is more efficient than large volume area with equipment around the central axis. A circular corridor is just wasted space and requires a lot of movement to go from one work area to another and you can't see what's going on on the other side of the central column. A central corridor allows you to access the 4 work areas around you just by turning around and you have a clear line of sight over the entire module.

A large empty volume carries no major benefit (other than maybe some extra comfort). In fact, it's harder to move around in microgravity in a large volume area than in a series of corridors. Skylab crews complained that they could sometimes get stuck out of reach of a handrail or a wall, and had to wait until they drifted within reach.

Edited by Nibb31
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3 hours ago, Nibb31 said:

A large empty volume carries no major benefit (other than maybe some extra comfort).

Uh, I mostly agree with you, but for a long enough mission (where how long is "long enough" is still an open question, as far as I know) that extra comfort may prove to be an actual major benefit. Of course Bigelow behaves as if it "long enough" was established and less than a year (which we know it's not), but I wouldn't dismiss the issue as much as (I think) you do.

Though personally I don't think long-term space missions will become viable before (and if) we can build habitats in space, from stiff materials. Of course inflatables may (or may not) remain situationally useful, but I'd be really surprised if they became common.

That doesn't mean I don't watch them with interest. Tech doesn't have to be useful to be cool to watch, though spending lots of money on something that's just cool is another matter. But it's not *my* taxes.

Edited by ModZero
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51 minutes ago, ModZero said:

Uh, I mostly agree with you, but for a long enough mission (where how long is "long enough" is still an open question, as far as I know) that extra comfort may prove to be an actual major benefit.

Submarine crews manage pretty well in smaller spaces for long duration missions. So do ISS crews. The comfort of a larger habitat to float around in is not necessary and not worth the extra complexity and effort.

 

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20 minutes ago, Nibb31 said:

Submarine crews manage pretty well in smaller spaces for long duration missions.

AFAIK that long duration isn't that long, compared to ISS deployments, and they're not continuous. ISS deployments aren't all that long either, not on the grand scale — less than year and a half. And not that many of them. This really isn't enough to draw conclusions.

EDIT: agh, 80-100 days is obviously pretty close to ISS deployment.

Edited by ModZero
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8 hours ago, Nibb31 said:

You need a cargo flight (probably several ones even) to bring up the equipment that didn't fit inside the deflated module. The inflatable module is heavier than an empty ISS module. Whereas the ISS module is pre-equipped on the ground, the BA330 goes up with only some of its equipment. It also needs to carry a whole stack of internal walls, floors, wiring, railing, plumbing, etc... that need to be installed after the inflation. That's a lot of assembly work for the crew before it can be operational, which probably requires at least one separate dedicated manned mission, so you need at least 3 launches before the hab is operational.

Also, an ISS-type module with equipment racks on the outer walls is more efficient than large volume area with equipment around the central axis. A circular corridor is just wasted space and requires a lot of movement to go from one work area to another and you can't see what's going on on the other side of the central column. A central corridor allows you to access the 4 work areas around you just by turning around and you have a clear line of sight over the entire module.

A large empty volume carries no major benefit (other than maybe some extra comfort). In fact, it's harder to move around in microgravity in a large volume area than in a series of corridors. Skylab crews complained that they could sometimes get stuck out of reach of a handrail or a wall, and had to wait until they drifted within reach.

The BA-330 is designed so that getting out of reach is not a problem- its basic version has a interior and exterior wall attached.

Oh come on, it's not like you can see extra modules in a ISS-type module (and layout) that does not extend out to your sides. And considering astronauts have radio transmitters to talk with each other and the ground, it's not really a huge problem

There needs to be outfitting, but it's not as bad as things like, say, wet workshop. You can put plumbing, walls, floors, etc using fabric or plastic materials that are not as rigid. And this image of the BA-330BA330.jpg

shows there is a huge amount of interior space to place all the equipment in before launch- especially since equipment storage tends to be lot more compressed than a purely ground-outfitted module.Seriously, if there is something that won't fit in the interior walls, which are about 2/3 the diameter of Destiny, in a storage pre-launch configuration, it probably isn't going to fit in a 14 ft fully outfitted ISS module either.

Also, wall mass for ISS modules is huge. Compare the empty masses of the Leonardo module to its full mass. https://www.nasa.gov/mission_pages/station/structure/elements/pmm.html#.VvHI0EZxSrk

5 hours ago, ModZero said:

Uh, I mostly agree with you, but for a long enough mission (where how long is "long enough" is still an open question, as far as I know) that extra comfort may prove to be an actual major benefit. Of course Bigelow behaves as if it "long enough" was established and less than a year (which we know it's not), but I wouldn't dismiss the issue as much as (I think) you do.

Though personally I don't think long-term space missions will become viable before (and if) we can build habitats in space, from stiff materials. Of course inflatables may (or may not) remain situationally useful, but I'd be really surprised if they became common.

That doesn't mean I don't watch them with interest. Tech doesn't have to be useful to be cool to watch, though spending lots of money on something that's just cool is another matter. But it's not *my* taxes.

Tourists like having extra space for comfort. And the stuff inflatables are made of are pretty darned common. When you're going into deep space, more than ever, every gram counts- so using a cheaper material for walls has far less benefit.

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8 hours ago, fredinno said:

The BA-330 is designed so that getting out of reach is not a problem- its basic version has a interior and exterior wall attached.

Oh come on, it's not like you can see extra modules in a ISS-type module (and layout) that does not extend out to your sides. And considering astronauts have radio transmitters to talk with each other and the ground, it's not really a huge problem

I didn't say they would get stuck in the middle of the module and die there. I said it was an annoyance to drift away from a wall and have to wait until you drift to the other side or the air recirculation pushes you around. The issue was annoying enough for Skylab astronauts to raise it and for NASA to want to avoid large empty spaces in subsequent space station designs.

8 hours ago, fredinno said:

There needs to be outfitting, but it's not as bad as things like, say, wet workshop. You can put plumbing, walls, floors, etc using fabric or plastic materials that are not as rigid. And this image of the BA-330BA330.jpg

In that picture, most of that inflated space is actually wasted. There is nothing in it and there is simply no need for it. If you want to fill that space, you are going to have to launch multiple cargo missions to fill it up.

Remember BA330 is 20t empty. Destiny was 15MT equipped. BA330 is still heavier and carries less equipment.

8 hours ago, fredinno said:

Tourists like having extra space for comfort. And the stuff inflatables are made of are pretty darned common. When you're going into deep space, more than ever, every gram counts- so using a cheaper material for walls has far less benefit.

Oh yeah, tourists. *yawn* The only application that empty space might have is recreation for tourists. Wake me up when you have a decent business model for that.

For the moment, neither private customers nor NASA are interested, and there are good reasons for that.

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11 hours ago, fredinno said:

Tourists like having extra space for comfort.

Tourists are an infra-red herring. Orbital is different from a suborbital jump, it's too expensive, takes too much time, and volume isn't the only thing that makes it uncomfortable. There are very few people who could afford it, and even fewer who have health, money and will at the same time.

Doesn't mean this won't ever happen, but it will be like ISS self-funded tourism — and there were far too few of them. A launch of a 20t module is going to require a heavy-ish launcher (Ariane 5/6, Proton, Angara, Long March 5), so you're paying at least 50M (probably much more, possibly twice as much, but hey, I'm being super optimistic here) just for that. A space tourist nets you 20-40M, if said tourist teleports themselves into your space station from their doorstep and doesn't use much oxygen, food or anything. Not that consumption will be a problem, because they won't stay there longer than two weeks, and you'll see them once every few years.

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12 hours ago, Nibb31 said:

I didn't say they would get stuck in the middle of the module and die there. I said it was an annoyance to drift away from a wall and have to wait until you drift to the other side or the air recirculation pushes you around. The issue was annoying enough for Skylab astronauts to raise it and for NASA to want to avoid large empty spaces in subsequent space station designs.

In that picture, most of that inflated space is actually wasted. There is nothing in it and there is simply no need for it. If you want to fill that space, you are going to have to launch multiple cargo missions to fill it up.

Remember BA330 is 20t empty. Destiny was 15MT equipped. BA330 is still heavier and carries less equipment.

Oh yeah, tourists. *yawn* The only application that empty space might have is recreation for tourists. Wake me up when you have a decent business model for that.

For the moment, neither private customers nor NASA are interested, and there are good reasons for that.

No, BA-330 is 16 T empty, according to: http://www.projectrho.com/public_html/rocket/transhabcalc.php

The 20T number is considered "lightly furnished". However, a full Lab module can go up to 41T, which basically makes use of all the space in the module.

That can still be launched in one shot by an expendable Falcon Heavy. But I see you'd likely need one resupply flight before it is operational.

Also, that picture is an example, not what it WILL look like. Seriously, you can also add interior walls. A la transhab http://www.projectrho.com/public_html/rocket/basicdesign.php#id--Habitat_Module

There is no reason all the space must go unused, especially when BA-330 actually has smaller corridors and does not require interior walls.

Also, I wasn't talking that tourists want empty space. You think I'm that stupid? I said that tourists want to have more spacious environments.

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