Author Topic: Off-the-wall ideas for things to do with Bigelow modules (and inflatable walls)  (Read 18632 times)

Offline Garrett

  • Full Member
  • ****
  • Posts: 1134
  • France
  • Liked: 128
  • Likes Given: 113
Per the suggestion of Neilh, I've opened this topic on off-the-wall ideas for things to do with Bigelow modules and inflatable walls in general.

I originally enquired whether it would be feasible to envelop an asteroid with a large Bigelow style module, with the aim of allowing astronauts to work in a short sleeve environment:
http://forum.nasaspaceflight.com/index.php?topic=20044.msg580201#msg580201

Neilh's off-the-wall idea was to build around an asteroid with inflatable module type material.
http://forum.nasaspaceflight.com/index.php?topic=20044.msg580372#msg580372

Apart from building space hotels, what else can one do with an inflatable module? I've seen a thread on an inflatable reentry vehicle, so any suggestions on that subject should probably go in that thread.

Cheers,
- "Nothing shocks me. I'm a scientist." - Indiana Jones

Offline Downix

  • Senior Member
  • *****
  • Posts: 7082
  • Liked: 22
  • Likes Given: 1
If I had the money, I'd use them for a space refinery, processing asteroids into base metals.
chuck - Toilet paper has no real value? Try living with 5 other adults for 6 months in a can with no toilet paper. Man oh man. Toilet paper would be worth it's weight in gold!

Offline space_man

  • Full Member
  • *
  • Posts: 139
  • Liked: 0
  • Likes Given: 0
With inflatable modules, I would build greenhouses for growing food on various moons of our solar system (phobos, titan, etc...)

Offline RanulfC

  • Senior Member
  • *****
  • Posts: 4595
  • Heus tu Omnis! Vigilate Hoc!
  • Liked: 900
  • Likes Given: 32
Bigelow has proposed the "off-the-wall-idea" of using his modules for building planetary bases as well as space-based use :)

Anyone have any idea how "insulative" the materials are? I'd thought of maybe using the material sucked down to vacuum with the "standard" inflation layers having an argon gas fill, (just enough to seperate the layers) or aerogel and using the material as propellant tank insulation.
It would then get "filled" out properly on-orbit as debris armor AND insulation...
(And of course making the original "tankage" capable of being used as habitation space :) )

Randy
From The Amazing Catstronaut on the Black Arrow LV:
British physics, old chap. It's undignified to belch flames and effluvia all over the pad, what. A true gentlemen's orbital conveyance lifts itself into the air unostentatiously, with the minimum of spectacle and a modicum of grace. Not like our American cousins' launch vehicles, eh?

Offline Jim

  • Night Gator
  • Senior Member
  • *****
  • Posts: 37440
  • Cape Canaveral Spaceport
  • Liked: 21451
  • Likes Given: 428

Neilh's off-the-wall idea was to build around an asteroid with inflatable module type material.
http://forum.nasaspaceflight.com/index.php?topic=20044.msg580372#msg580372


Not really feasible with a Bigelow module.  The backbone of the module is the center truss section.

Offline Garrett

  • Full Member
  • ****
  • Posts: 1134
  • France
  • Liked: 128
  • Likes Given: 113

Neilh's off-the-wall idea was to build around an asteroid with inflatable module type material.
http://forum.nasaspaceflight.com/index.php?topic=20044.msg580372#msg580372


Not really feasible with a Bigelow module.  The backbone of the module is the center truss section.

Hmmm, that may create a slight problem  :o
Thank's for pointing that out!
- "Nothing shocks me. I'm a scientist." - Indiana Jones

Offline TOG

  • Full Member
  • **
  • Posts: 223
  • Near Chicago, Illinois
  • Liked: 65
  • Likes Given: 58

Neilh's off-the-wall idea was to build around an asteroid with inflatable module type material.
http://forum.nasaspaceflight.com/index.php?topic=20044.msg580372#msg580372


Not really feasible with a Bigelow module.  The backbone of the module is the center truss section.

Hmmm, that may create a slight problem  :o
Thank's for pointing that out!

Garrett - Don't give up on it quite so fast.  Maybe there is a way:

            What if you use the asteroid AS the backbone?  Deliver the inflatable module in two parts.  Plant the connection point of one half on one side of the asteroid, and plant the other on the opposite side.  Have the inflatable material drape over the surface and meet up with its opponent at the half way point.  Attach the two halves- sealing them as you follow the seam, then go to one of the two ready made "ports" and start filling with the gas of choice.

I got there by wondering to myself, how do you get an asteroid into an inflatable habitat?  Any other options?
M's Laws of Aerodynamics:                                    On Physics Exam:
1) if you push anything hard enough it will fly          Q)The allegory of Schrödinger's cat shows what?
2) if you stop pushing it stops flying                        A)That Shrödinger was a sadistic cat hater

Offline aero

  • Senior Member
  • *****
  • Posts: 3629
  • 92129
  • Liked: 1146
  • Likes Given: 360
Not to put to fine a point on it, but why not just make a big bag with a drawstring. Have the top rolled down all the way, put it top down on the asteroid then unroll it and pull the drawstring tight. Seal it. The asteroid is inside, inflate the bag, go inside and erect the previously placed back bones or ribs. After the bag is sealed you can do most of the work in shirtsleeves.

Actually, wouldn't it be possible to plant some anchors in the asteroid with cables attached, then as you unroll the bag, attach the cables to the bag. Once the bag is inflated, the cables will be in tension and serve to transfer forces to the asteroid, which is now your backbone. At least for a solid rock. Might not work for a rubble pile without reinforcement of the asteroid. If the bag is double or multi-walled, then you could probably unroll it just by putting gas pressure between the walls. Probably need to anchor the bottom of the bag to the asteroid though, else the pressure of unrolling might catch the asteroid and send it off someplace else.

NOTE: The drawstring part is just conceptual. Overlapping flaps might work better, and I bet there are a lot of other ways to seal a bag, including zippers. A double set of closures could allow for an over sized airlock if you have any use for it.
« Last Edit: 04/26/2010 11:18 pm by aero »
Retired, working interesting problems

Offline Commander Keen

  • Member
  • Posts: 98
  • Liked: 1
  • Likes Given: 0
If an inflatable could be used as a space station somewhere (lunar orbit, LaGrange point, etc.) how hard would it be to design one that rotates to create artificial gravity.  I was thinking a design like the station like in the movie 2001.  It seem it would be incredibly difficult to say the least.

The only thing I worry about with inflatable habs is the stability.  Will it flex, etc like a balloon?  I guess I am not sure of its stiffness?

Nonetheless a very creative idea to say the least...

Offline neilh

  • Senior Member
  • *****
  • Posts: 2365
  • Pasadena, CA
  • Liked: 46
  • Likes Given: 149
A related question: Is the goal to have the asteroid-containing interior breathable, or simply pressurized? Some consequences of each:

Breathable: No breathing apparatus required, but I suspect it won't take much to get asteroid dust suspended in the air, making it impossible to breath without some sort of mask. You'd also need to worry about oxygen's effect on whatever you're trying to work with or mine.

Non-breathable pressurized (perhaps with nitrogen?): Potential for shirtsleeves operation while wearing a breathing apparatus.
Someone is wrong on the Internet.
http://xkcd.com/386/

Offline neilh

  • Senior Member
  • *****
  • Posts: 2365
  • Pasadena, CA
  • Liked: 46
  • Likes Given: 149
Speaking of off-the-wall ideas, I don't think there's ever been an update about the results of this planned experiment from back in 2007:

http://cosmiclog.msnbc.msn.com/archive/2007/02/22/65477.aspx
Quote
Q: I’ll definitely return to that in a second, but I did want to ask you about your approach to the base and the regolith insulation. Someone coming in from the outside might say, “Well, you just take one of those inflatable modules and you plunk that down on the lunar surface and pile moon dirt around it. It doesn’t sound that complicated.” Is the devil in the details, or is there some radically different way in which Bigelow would approach that challenge?

A: Yes, there’s a significant difference, because both of those are very significant challenges.

The regolith is made up of very, very fine, talcum-powder-type of glass particles. As you probably know, these particles are a significant abrasive, and they are able to penetrate the smallest of joints in any moving system. So what you don’t want to have, if possible, is a reliance on any moving systems to deploy that material.

...

So our solution is something entirely different, involving a method where no machinery actually is used. We’re going to be trying the method this year, using one of our steel simulators as a prototype, because it’s the size of vessel that mimics the full-scale module. We’re actually going to try in Las Vegas to apply our solution for covering up a full-scale module, involving only two people, with a depth of soil on the crown of at least 2 or 3 feet. We’ll give you more on this later as we progress with this experiment.

Q: You don’t want to go into detail on the particular strategy involved?

A: Well, part of it is because we would prefer to actually implement our approach first. The other part is that I don’t have a lot of time left right now to explain it. It would take me probably 15 minutes to describe the process to you. … Maybe another time.


I never saw more information about it, but I guessed it might involve temporarily making the habitat more dense than the regolith (by having it deflated and/or filling it with something dense) and then vibrating it until it sunk to a sufficient depth. Any other ideas on how you might bury a Bigelow module in regolith? What's known about the density of lunar regolith?
Someone is wrong on the Internet.
http://xkcd.com/386/

Offline PMN1

  • Full Member
  • **
  • Posts: 280
  • Liked: 5
  • Likes Given: 0
« Last Edit: 10/11/2010 04:58 pm by PMN1 »

Offline chrisking0997

  • Full Member
  • ***
  • Posts: 355
  • NASA Langley
  • Liked: 127
  • Likes Given: 317
water or fuel tanks, either for stations or a depot.  Somehow use their inflation/deflation process to fill or drain the tanks as needed (suction during inflation for filling, pressure during deflation for offload).

Tried to tell you, we did.  Listen, you did not.  Now, screwed we all are.

Offline pathfinder_01

  • Senior Member
  • *****
  • Posts: 2074
  • Liked: 271
  • Likes Given: 8
Change the light bulbs to red lights and open the first red light district in space.

Put a disco ball in the middle and some bad 70ies décor and open a disco on orbit.

Install granite counter tops, hard wood flooring, and stainless steel appliances and film episodes for HGTV.

Lots of things you can do with  one.

Offline khallow

  • Extreme Veteran
  • Full Member
  • ****
  • Posts: 1954
  • Liked: 8
  • Likes Given: 4
One use I can see for an inflatable structure is simply something to keep loose parts from floating away. You need enough internal pressure to keep the structure rigid, maybe 1 PSI of a chemically neutral gas like nitrogen or argon (that is, air with the oxygen removed) would be enough. For example, things like welding or spraying adhesive have a tendency to generate a lot of loose material.
Karl Hallowell

Offline alexterrell

  • Full Member
  • ****
  • Posts: 1747
  • Germany
  • Liked: 184
  • Likes Given: 107
Don't get carried away with Bigelow modules.

Yes, they're great for quick pop up in space, where no ISRU is available.

The moment you can handle regolith (Asteroid, Moon, Phobos etc) they are extravagant. With regolith for shielding a 25m diameter dome can be got into 20 tons of material. The equivalent Bigelow design would mass well over a 100 tons.

Most of the Bigelow mass is designed to stop micro meteorites and provide thermal insulation. Regolith can do that even better.

Now, for inflatable walls!
http://forum.nasaspaceflight.com/index.php?topic=20684.msg554021#msg554021

Offline KelvinZero

  • Senior Member
  • *****
  • Posts: 4286
  • Liked: 887
  • Likes Given: 201
I have no idea what this is actually for.. but if you had a really big balloon full of water in space, and it was spinning just a little bit, I guess any air would sit in a sort of wobbly tube down its axis. Just imagine swimming down something like that, or for that matter since the gravity is so low, you could probably run down it.

Offline Sparky

  • Full Member
  • ***
  • Posts: 378
  • Connecticut
  • Liked: 0
  • Likes Given: 0
Launch a Bigelow-derived module on SLS with a core that would be nearly the whole 8.4 meters. Have a very large airlock at one end that would take up most of the end. Create a hangar for reusable landers and in-space vehicles to repaired and maintained in a shirtsleeve environment.

Offline Patchouli

  • Senior Member
  • *****
  • Posts: 4490
  • Liked: 253
  • Likes Given: 457
With Bigelow's inflatable technology and the large payload of SLS I'd want to launch one of these.
The wheel section would be inflatable and maybe have an internal frame that can be assembled once it's in orbit while the core with be conventional.
« Last Edit: 10/15/2010 06:24 am by Patchouli »

Offline mr. mark

  • Full Member
  • ****
  • Posts: 1996
  • Liked: 172
  • Likes Given: 0
Heck, if all else fails Sundancer would make one heck of a bounce house! :)

Offline Sparky

  • Full Member
  • ***
  • Posts: 378
  • Connecticut
  • Liked: 0
  • Likes Given: 0
Heck, if all else fails Sundancer would make one heck of a bounce house! :)
In particular, I'd think it would be neat to create a functional version of the battle-room from Ender's Game for space tourists.

Offline PMN1

  • Full Member
  • **
  • Posts: 280
  • Liked: 5
  • Likes Given: 0
With Bigelow's inflatable technology and the large payload of SLS I'd want to launch one of these.
The wheel section would be inflatable and maybe have an internal frame that can be assembled once it's in orbit while the core with be conventional.

Bit like this?

There was a paper in the December 1991 issue of the Journal of the British Interplanetary Society by Michael A Minovitch of Phaser Telepropulsion Inc proposing the building of rotating 2001 type stations 100 metres diameter for at least 150 crew by using automatic wrapping machines rotating round inflated Kevlar torus’ to wind thin layers of aluminium until the required thickness had been made.

The rotating toroidal living section would have a major and minor radii of 100m and 2m while the two central column cylinders with labs etc and constructed in the same way would each be 100m long x 10m diameter. The two column cylinders would connect into a pre-fabricated central hub into which three spokes 100m long x 4m diameter also constructed in the same way would be fitted to join the hub to the toroidal living section.

The station also served as the basis for a 'cycling' ship and would take about 10 HLLV (assuming 100 tons/launch) or 14 Shuttle-C launches and 1 STS flight with minimal EVA.

Costs were about $400 billion for an Earth orbit station, a Mars orbit station and a cycling ship

Offline spacester

  • Member
  • Full Member
  • ***
  • Posts: 332
  • Liked: 41
  • Likes Given: 178
How about a Solar System Cruiser?

Toroidal shapes are great, but given the existence of BA-330 modules how would you create a spin-gravity vehicle capable of transporting a large crew to Mars?

My idea is to build it in Earth orbit as a touristy vehicle and once all is ready, fly the thing to Mars.

The purpose would be to create a safe haven for intrepid explorers and as such, the spin radius would need to be large enough to keep the rotation rate low enough to minimize coriolis effects. Specifically, a 100 meter radius at 3 rpm would provide a very nice 1 gee environment.

People talk about tethered spin ships and as an engineer I shudder. I want a more rigid body than that and as a safe haven a ship spinning at the end of a rope is not acceptable.

So I came up with this monstrosity: 4 BA-330s (blue) connected by rigid tubes to a central hub (white) and a stowage room (red).

The central hub and stowage would be constructed robotically from raw materials (bar and sheet stock). The 4 radial attachment points for the tubes, along with the 2 axial docking ports, would be the most sophisticated elements. The central hub construction would be a new challenge, but the idea would be to minimize the requirements to keep it as close as possible to simply having to provide structure and a pressurized volume. It would also have to include a minimal environmental system for the air handling. Once you have a pressure vessel, you wrap it with Bigelow multi-layer stuff and you're good to go long term.

Of course once you can build spaceships like this, you find you're a space-faring species, which is kinda the whole point for me.

The connecting tubes would be launched in segments and robotically assembled. They would of course not be transparent as shown. Maybe they are inflatable radially but need to support both compressive and tensile loading axially.

So then you add the 4 BA_330 modules and their mechanical modules to connect to the tubes. Then you rig it with cables to stiffen the whole thing up.

Propulsion is not shown, it would go on the other side of the white hub as the red stowage module. Additional mission equipment could go on the forward face of the stowage module.

I did this years ago ans at one point I had crude mass budgets and a launch vehicle breakdown, using Delta, Atlas and Falcon 9, all the while hoping that a heavy lifter is built sooner than later.

If you think this is off the wall, well so be it. :D But if you want some truly off the wall but hey man I'm kinda serious here stuff, just ask me about my propulsion system for this beast.

Offline Sparky

  • Full Member
  • ***
  • Posts: 378
  • Connecticut
  • Liked: 0
  • Likes Given: 0
Beautiful! Only one thing, might it not be possible to just replace the tunnels with nothing but BA330s end to end? Especially with all those cables adding support.

Offline spacester

  • Member
  • Full Member
  • ***
  • Posts: 332
  • Liked: 41
  • Likes Given: 178
Beautiful! Only one thing, might it not be possible to just replace the tunnels with nothing but BA330s end to end? Especially with all those cables adding support.

Thank you. As a conceptual design and not an engineering proposal, this was mostly about showing the a configuration you naturally end up with given a particular set of criteria:

1. Use BA-330 modules and provide spin-gravity of one gee at 3 rpm for somewhat more than a dozen crew.
2. Make it launch-able and assembly-friendly.
3. Pioneer LEO fabrication and construction techniques from raw material.
4. Be mass-efficient.
5. 50+ year service life.

The tubes are a compromise between tension cables (tethers) and providing large diameter multi-deck working space all the way to the axis. The former might be more mass efficient with a low safety factor but as such not good for 50 years. The latter is not at all mass efficient. Cool, but not needed and hugely more expensive.

The idea is to put your expensive hab modules at maximum distance from the spin axis. The criteria do not call for providing habitat over a range of lower gee values.

The tubes provide the ability to transit between modules at will; if using tethers any transits would be EVAs. The conceptual design shown is very primitive.

Even more notional are the cables. For all I know you would only need from zero to 4 of them. Much dynamic modeling required. They are there as placekeepers to get the stiffness needed, and also as a potential latticework upon which to mount solar panels.

Employed as a Mars Cruiser and safe haven in Martian orbit, the thing I like best is probably the ability to have 4 separate teams, with the ability to "go somewhere else" a bit. Interpersonal conflicts could be mitigated by separating the individuals.

I was originally thinking 28 total crew but now I think 20 is better.

Offline FinalFrontier

  • Senior Member
  • *****
  • Posts: 4490
  • Space Watcher
  • Liked: 1332
  • Likes Given: 173
With Bigelow's inflatable technology and the large payload of SLS I'd want to launch one of these.
The wheel section would be inflatable and maybe have an internal frame that can be assembled once it's in orbit while the core with be conventional.
Could it perhaps be assembled at L1/l2? Gateway station ;)
3-30-2017: The start of a great future
"Live Long and Prosper"

Online MickQ

  • Full Member
  • ****
  • Posts: 868
  • Australia.
  • Liked: 191
  • Likes Given: 627
Beautiful! Only one thing, might it not be possible to just replace the tunnels with nothing but BA330s end to end? Especially with all those cables adding support.

Thank you. As a conceptual design and not an engineering proposal, this was mostly about showing the a configuration you naturally end up with given a particular set of criteria:

1. Use BA-330 modules and provide spin-gravity of one gee at 3 rpm for somewhat more than a dozen crew.
2. Make it launch-able and assembly-friendly.
3. Pioneer LEO fabrication and construction techniques from raw material.
4. Be mass-efficient.
5. 50+ year service life.

The tubes are a compromise between tension cables (tethers) and providing large diameter multi-deck working space all the way to the axis. The former might be more mass efficient with a low safety factor but as such not good for 50 years. The latter is not at all mass efficient. Cool, but not needed and hugely more expensive.

The idea is to put your expensive hab modules at maximum distance from the spin axis. The criteria do not call for providing habitat over a range of lower gee values.

The tubes provide the ability to transit between modules at will; if using tethers any transits would be EVAs. The conceptual design shown is very primitive.

Even more notional are the cables. For all I know you would only need from zero to 4 of them. Much dynamic modeling required. They are there as placekeepers to get the stiffness needed, and also as a potential latticework upon which to mount solar panels.

Employed as a Mars Cruiser and safe haven in Martian orbit, the thing I like best is probably the ability to have 4 separate teams, with the ability to "go somewhere else" a bit. Interpersonal conflicts could be mitigated by separating the individuals.

I was originally thinking 28 total crew but now I think 20 is better.

I like it.  It could be assembled in stages with the arms starting out short and a high spin rate for a test period and then add another arm section and spin at a slower rate etc.  Eventually you would get data on various G's and rotation speeds.

A thought about the arms.  What if you made them out of a square or circular truss section surrounded by a tube that seals between the hub and the hab module ?  As construction continues you un-hook the hab, bolt in another truss section, re-attach the hab and the tube and re pressurize.  Maybe the tube could be bunched up at the hub end, just like a sleeve pulled up, and just extended as more truss sections are added.

Now, what about your propulsion idea ???

Mick.

Offline Lampyridae

  • Veteran
  • Senior Member
  • *****
  • Posts: 2641
  • South Africa
  • Liked: 949
  • Likes Given: 2056
The purpose would be to create a safe haven for intrepid explorers and as such, the spin radius would need to be large enough to keep the rotation rate low enough to minimize coriolis effects. Specifically, a 100 meter radius at 3 rpm would provide a very nice 1 gee environment.

You could reasonably get it down to the radius of the Bigelow habitat.

Quote
People talk about tethered spin ships and as an engineer I shudder. I want a more rigid body than that and as a safe haven a ship spinning at the end of a rope is not acceptable.

I agree. Tethers are a bad idea, especially with people running around in it. They have a nasty habit of whipping around and oscillating without something to damp them down.

Quote
So I came up with this monstrosity: 4 BA-330s (blue) connected by rigid tubes to a central hub (white) and a stowage room (red).

The central hub and stowage would be constructed robotically from raw materials (bar and sheet stock). The 4 radial attachment points for the tubes, along with the 2 axial docking ports, would be the most sophisticated elements. The central hub construction would be a new challenge, but the idea would be to minimize the requirements to keep it as close as possible to simply having to provide structure and a pressurized volume. It would also have to include a minimal environmental system for the air handling. Once you have a pressure vessel, you wrap it with Bigelow multi-layer stuff and you're good to go long term.

Nice idea. I was thinking of something similar for ultra-large modules, such as small space colonies.

Quote
Of course once you can build spaceships like this, you find you're a space-faring species, which is kinda the whole point for me.

The connecting tubes would be launched in segments and robotically assembled. They would of course not be transparent as shown. Maybe they are inflatable radially but need to support both compressive and tensile loading axially.

Quote
So then you add the 4 BA_330 modules and their mechanical modules to connect to the tubes. Then you rig it with cables to stiffen the whole thing up.

Propulsion is not shown, it would go on the other side of the white hub as the red stowage module. Additional mission equipment could go on the forward face of the stowage module.

I did this years ago ans at one point I had crude mass budgets and a launch vehicle breakdown, using Delta, Atlas and Falcon 9, all the while hoping that a heavy lifter is built sooner than later.

If you think this is off the wall, well so be it. :D But if you want some truly off the wall but hey man I'm kinda serious here stuff, just ask me about my propulsion system for this beast.

Ha, if you liked that you're gonna loooove this:

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20070023306_2007019854.pdf

Offline Lampyridae

  • Veteran
  • Senior Member
  • *****
  • Posts: 2641
  • South Africa
  • Liked: 949
  • Likes Given: 2056
Heck, if all else fails Sundancer would make one heck of a bounce house! :)

Once inflated, the walls are like concrete...  :P

Offline spacester

  • Member
  • Full Member
  • ***
  • Posts: 332
  • Liked: 41
  • Likes Given: 178
The purpose would be to create a safe haven for intrepid explorers and as such, the spin radius would need to be large enough to keep the rotation rate low enough to minimize coriolis effects. Specifically, a 100 meter radius at 3 rpm would provide a very nice 1 gee environment.

You could reasonably get it down to the radius of the Bigelow habitat.

<snip>

Ha, if you liked that you're gonna loooove this:

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20070023306_2007019854.pdf

Ooooh that was a fun read, thanks. One thing it points out is just how little we know, which I take as a signal that the priority needs to move up. Bigelow is real folks, it's OK to dream about these things.

Fun read not least because the mission archetype and its foundational logic tracked very closely with mine, right up to a certain point. I was working from the same references and have quoted those same paragraphs in my posts many times.

With essentially no data, in a perfect world the purpose of constructing the first of such ships would be to get that data. But ultimately you construct a spin ship in order to go somewhere BEO and a Mars mission is the obvious profile. An LEO hotel with 1 g spin gravity has its place in the grand scheme but the origin of spin-g is the desire of going into deep space without the humans wasting away to weaklings. It's about robust human Martian explorers.

The idea here is to operate as a space hotel ASAP during construction, milk that revenue while you get it all good to go for Mars. You take your sweet time if you have to, make sure you like all your systems operations. Like in the paper, it is a split mission in that surface habs and pretty much everything else would be sent by itself or already be in place. In fact, this cruiser would not be a critical path or lynch pin in the overall exploration of Mars, but it would be basically awesome once it gets there.

Which is where the departure between that paper and my configuration begins: I am interested in providing relative luxury for our Martian Explorers.

This is an expression of an abundance mentality where the idea is "you want mission margin? I'll give you mission margin: massive amounts of fresh water, power, pressurized volume, food, medical room, greenhouse, spa and just a sweet refuge in Martian orbit for R & R between surface missions."

In terms of configuration, this means that split habitation volume is OK and in fact desired, so that there is free movement between the multiple hab modules. Combined with the fact that it does not use NEP (or any nukes other than RTG) this leads to a design with a central hub. The next step: a central hub on an "abundance mentality" space cruiser is going to be big. It will have massive water reserves and serve as the storm shelter.

That's what's illustrated anyway: a huge central hub with a detachable and even huger mission module. The hub could provide unparalleled radiation protection should "the big one" hit.

OTOH having individual shelter in each hab makes a lot of sense because it avoids the emergency evac to the hub, leaving the habs un-crewed.

Speaking of which, the fully pressurized volume tubes are quite the luxury. You would definitely look at other options, such as a capsule that shuttles back and forth on rails.

So this is the full-on luxury liner.

The propulsion is a whole other thread really. It's another enterprise in my imagined space empire, lol. So I'l at least do a separate post on that, next.

***
On the radius of a BA-2300 (is that the right number?) being enough that is an interesting question. I agree that you could reasonably get there for something that would help for maintaining the human body long-term in space. Absolutely, can-do. BUT.

Myself, I want to keep it to 3 RPM. That's just the number that I think we should use. For the luxury liner at 3 RPM, you get the radius illustrated.

Humans are very adaptable and you could push the limits. For lunar gravity at high RPM, let's see, at 7 RPM which I think is WAY too fast we'd have
R = (9.81 * 0.17) / [(pi*7) / 30]^2 = 3.10 meters
but at 5 RPM would be
R = (9.81 * 0.17) / [(pi*5) / 30]^2 = 6.08 meters

I've seen speculation on that giant module's radius, what 8 m maybe?

At 8m and 3 rpm you'd have:
G = [R * [(pi*rpm) / 30]^2] / 9.81
G = [8 * [(pi*3) / 30]^2] / 9.81
G = 0.08

And you have a gravity gradient. If your feet are at 8m and your head at 6m, you'd have
G = 0.06
which would be weird.

So you could spin a large hab but it seems to me the purpose would be to get data, not so much as to take care of astronauts.

Offline spacester

  • Member
  • Full Member
  • ***
  • Posts: 332
  • Liked: 41
  • Likes Given: 178
So a big space Cruiser is going to need a lot of impulse to get to Martian Orbit. Envisioned as a private, civilian ship, nuclear power and propulsion were ruled out.

Really, the main reason I ruled out solar Nuclear is to make this design harder, asking the question of whether that low power density power source can effectively support this whole off the wall abundance mentality concept. I am nowhere close to knowing that answer yet.

Which means PV solar for primary ship power. Those panels and all the radiators required are not shown, conceptually they would be in the same plane as the connecting tubes, attached to the cables shown.

I'm a rocket-power guy. VASIMR is awesome but I like the good old fashioned rocket engine and the mission profile of burn to inject, coast all the way, burn into orbit. Also desired is to use proven tech wherever possible on this.

Obviously, the engines, thrust structure and propellant will need to be brought to this monster and integrated into the ship for the bug trip to Mars.

But it is going to be loitering in LEO for years during construction and shakedown of the tourists, er systems. We can put that propulsion capability together slowly if that helps.

And as it turns out, in this fan-boy fantasy universe of mine there is another off-the-wall operation just dying to get our business on this.

It's the rocket-a-week company of course! They build their rockets cheap, fast and continuously and they supply commodities like food and water and deltaV.

So the propulsion for this cruiser is solid rocketry. A big cluster of dozens of solid rocket motors.

They plug into their sockets, which are integrated into a thrust structure using the same on-orbit final fabrication capability you're building the hub and mission module with. They come up on a regular basis, somebody fetches them for us and we plug them in.

For Trans-Mars Injection you light em up symmetrically and sequentially and you get your ~6 km/s dV for a tangent-on-arrival trajectory. On the cruise out, you pull the spent casings, bundle them up and do something fun with them after jettison.

Or arrival, you stay out of the atmosphere and burn the rest of the solids to get to your desired orbit. There are no plans to return to Earth, but there is a thrust structure to plug Martian-derived dV into, if you want.

I did some BOE calcs on this but can't find it. Conceptually, even with the modest specific impulse of solids, it seems to work, even if you have to design the rocket-a-week around the solid motors.

[EDIT] D'oh! I said "ruled out Solar" when I meant "ruled out Nuclear" duh, sorry I didn't catch that sooner.[/EDIT]
« Last Edit: 10/29/2010 04:37 pm by spacester »

Offline A_M_Swallow

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 8906
  • South coast of England
  • Liked: 500
  • Likes Given: 223
{snip}

Really, the main reason I ruled out solar is to make this design harder, asking the question of whether that low power density power source can effectively support this whole off the wall abundance mentality concept. I am nowhere close to knowing that answer yet.

Which means PV solar for primary ship power. Those panels and all the radiators required are not shown, conceptually they would be in the same plane as the connecting tubes, attached to the cables shown.

You can also put the solar panels on the back of the spacecraft and rotate them in the opposite direction.  Ordinary electric motors as used on Earth can be used to power the rotations.

Online MickQ

  • Full Member
  • ****
  • Posts: 868
  • Australia.
  • Liked: 191
  • Likes Given: 627
{snip}

Really, the main reason I ruled out solar is to make this design harder, asking the question of whether that low power density power source can effectively support this whole off the wall abundance mentality concept. I am nowhere close to knowing that answer yet.

Which means PV solar for primary ship power. Those panels and all the radiators required are not shown, conceptually they would be in the same plane as the connecting tubes, attached to the cables shown.

You can also put the solar panels on the back of the spacecraft and rotate them in the opposite direction.  Ordinary electric motors as used on Earth can be used to power the rotations.

Why would you need do that ???

Mick.

Offline spacester

  • Member
  • Full Member
  • ***
  • Posts: 332
  • Liked: 41
  • Likes Given: 178
{snip}

Really, the main reason I ruled out solar is to make this design harder, asking the question of whether that low power density power source can effectively support this whole off the wall abundance mentality concept. I am nowhere close to knowing that answer yet.

Which means PV solar for primary ship power. Those panels and all the radiators required are not shown, conceptually they would be in the same plane as the connecting tubes, attached to the cables shown.

You can also put the solar panels on the back of the spacecraft and rotate them in the opposite direction.  Ordinary electric motors as used on Earth can be used to power the rotations.

I'm sorry A_M_Swallow, I confused you with my error, which I just edited. I stupid.

I ruled out nuclear, not solar. So I'm sure I confused you.

A point of clarification: another basic design principle was no rotary joints. This is all brought together as one mass, rigged up, spun up and pushed to Mars.

Spin-up and spin-down is easy in itself. It's only the shift in operational modes that make it an issue, the propellant mass is surprisingly small. So crew transfer (including private space adventurers) happens in the de-spun mode, probably out by the BA-330 modules.

A "2001: A Space Odyssey"-style rotation-matching docking is not in the cards for this craft until you get to Martian orbit. You need to get good at quickly transitioning between zero-g and spin-g anyway, just for general emergency preparedness. The thing is constantly under construction at the hub and providing docking at the axis and pressurized passage to the habs is asking too much of the design and ops.

The paying customers would experience a full cycle of arriving in zero-g, moving in and executing the tasks to get it spun up the next day or so. They stay, and then they de-camp. You actually could "simply" release their capsule and not have to spin down until new people arrive.

Once you shed the huge mission module - perhaps sending it to the Phobos people - then you would have a space station in its final orbit and with access to the axis for docking without de-spinning.

Offline A_M_Swallow

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 8906
  • South coast of England
  • Liked: 500
  • Likes Given: 223
{snip}

Really, the main reason I ruled out solar is to make this design harder, asking the question of whether that low power density power source can effectively support this whole off the wall abundance mentality concept. I am nowhere close to knowing that answer yet.

Which means PV solar for primary ship power. Those panels and all the radiators required are not shown, conceptually they would be in the same plane as the connecting tubes, attached to the cables shown.

You can also put the solar panels on the back of the spacecraft and rotate them in the opposite direction.  Ordinary electric motors as used on Earth can be used to power the rotations.

Why would you need do that ???

Mick.

Ordinary electric motors do not need propellant, however conservation of angular momentum requires something to spin in the opposite direction.

Offline spacester

  • Member
  • Full Member
  • ***
  • Posts: 332
  • Liked: 41
  • Likes Given: 178
. . .  however conservation of angular momentum requires something to spin in the opposite direction.

Um, no it doesn't. Am I missing something here? That's like saying that catching a ball requires that another ball is thrown at the same time.

If you have zero angular momentum and then apply torque with thrusters you now have angular momentum. Apply torque in the opposite direction to spin down and you remove the angular momentum. The applied impulse cancels the existing momentum and momentum is conserved.

Offline Warren Platts

How about a simple Sundancer mated to a sun-shaded ACES 121?
"When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return."--Leonardo Da Vinci

Offline A_M_Swallow

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 8906
  • South coast of England
  • Liked: 500
  • Likes Given: 223
. . .  however conservation of angular momentum requires something to spin in the opposite direction.

Um, no it doesn't. Am I missing something here? That's like saying that catching a ball requires that another ball is thrown at the same time.

Yes inertia.  See Newton's laws.
http://en.wikipedia.org/wiki/Inertia

When you catch a ball the whole planet Earth acts as the 'second ball'.

Quote
If you have zero angular momentum and then apply torque with thrusters you now have angular momentum. Apply torque in the opposite direction to spin down and you remove the angular momentum. The applied impulse cancels the existing momentum and momentum is conserved.

The opposite momentum is applied to the exhaust gasses and you have used some of your propellant to do this.

Offline spacester

  • Member
  • Full Member
  • ***
  • Posts: 332
  • Liked: 41
  • Likes Given: 178

The opposite momentum is applied to the exhaust gases and you have used some of your propellant to do this.

Exactly so, which is why I mentioned that the propellant required for spin-up/spin down is not as much as many would think. I've done the calcs myself, I do space math for recreation and I know my physics.

I still think I must have explained something wrong because there is no reason whatsoever for anything to counter-rotate in the configuration I modeled and described.

Offline A_M_Swallow

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 8906
  • South coast of England
  • Liked: 500
  • Likes Given: 223

I still think I must have explained something wrong because there is no reason whatsoever for anything to counter-rotate in the configuration I modeled and described.

You were using thrusters that throw hot gas off, the gas forms an arc.  I was using electric motors, something that may be used in a car.

Offline Patchouli

  • Senior Member
  • *****
  • Posts: 4490
  • Liked: 253
  • Likes Given: 457

I still think I must have explained something wrong because there is no reason whatsoever for anything to counter-rotate in the configuration I modeled and described.

You were using thrusters that throw hot gas off, the gas forms an arc.  I was using electric motors, something that may be used in a car.

Thrusters probably would work any arcing could be avoided with a cold gas thrusters or just designing things in such a way any high voltage lines will not be exposed to the exhaust plume.

If you wish to avoid thrusters you could use a fly wheel to store the angular momentum and then use that same momentum when it comes time to despin the spinning section of the ship or space station.


Offline A_M_Swallow

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 8906
  • South coast of England
  • Liked: 500
  • Likes Given: 223

If you wish to avoid thrusters you could use a fly wheel to store the angular momentum and then use that same momentum when it comes time to despin the spinning section of the ship or space station.

The solar panels are acting as a large fly wheel.

Offline spacester

  • Member
  • Full Member
  • ***
  • Posts: 332
  • Liked: 41
  • Likes Given: 178

If you wish to avoid thrusters you could use a fly wheel to store the angular momentum and then use that same momentum when it comes time to despin the spinning section of the ship or space station.

The solar panels are acting as a large fly wheel.

Aha, I see now. As much as my beast is a luxury liner, one of the advantages to what I've worked out so far is following the dictate to have NO rotating joints. I should have listed it as a main criteria, but the 50-year lifetime spec also covers that design choice.

I'll have to work out the propellant mass for cold gas thrusters for spin control because to be honest IIRC when I did the calcs before I think I was figuring hot thrusters with much higher Isp. Still, proper engineering should allow e.g. SpaceX Draco engines as an option, I would think.

So maybe the prop mass is more of an issue than I thought. When I was just farting around I figured that perhaps excess methane might serve that purpose. ;)

The solar PV would need to be large and it is totally not shown. I'm anticipating that the spin axis will remain pointed away from the sun, so I anticipate finding plenty of room within the plane of the tubes. Perhaps integrated into the structure, but certainly not rotating independently.

I don't have my mass numbers anymore so such calculations are problematic. It was really only done to illustrate this configuration.

Offline Patchouli

  • Senior Member
  • *****
  • Posts: 4490
  • Liked: 253
  • Likes Given: 457

Aha, I see now. As much as my beast is a luxury liner, one of the advantages to what I've worked out so far is following the dictate to have NO rotating joints. I should have listed it as a main criteria, but the 50-year lifetime spec also covers that design choice.

A 50 year life timespec is probably overkill 15 to 20 years would be good enough as the vehicle will likely become outdated or at the very least require a complete refit to stay competitive by then.

It's best to look at early airlines as a model.

The Lockheed Constellation for example was state of the art in 1943 but was outdated by the late 1950s.
« Last Edit: 11/03/2010 02:55 am by Patchouli »

Offline spacester

  • Member
  • Full Member
  • ***
  • Posts: 332
  • Liked: 41
  • Likes Given: 178
Well, this whole internet fan-boy proposal of mine is about looking at this whole Man on Mars thing quite differently. The idea is to build this thing in LEO as a tourist destination, and that construction phase would take years. Only then do you take it to Mars, so if you're going to refurbish it would be at that time.

The ship's role as a safe haven in Mars orbit pretty much precludes refurbishment, and there does not seem to be a good reason to bring it back to Earth. Further, there would not be any commercial competition in Mars orbit. As long as it still serves its function it isn't obsolete.

The goal would be to keep this safe haven there to support a settlement for as many decades as possible. In fact, one major difficulty is how exactly to de-commission it, as letting it naturally decay seems unacceptable.

Offline spacester

  • Member
  • Full Member
  • ***
  • Posts: 332
  • Liked: 41
  • Likes Given: 178
Moving on, here's a whole new off-the-wall idea.

I'm actually surprised no one has mentioned it yet, I cannot imagine I'm the first to think of it:

A Hollywood Studio for filming actors in a weightless environment.

Just have Bigelow build it with a green screen color for the innermost fabric layer.

The public would LOVE it!

Offline gospacex

  • Senior Member
  • *****
  • Posts: 3024
  • Liked: 543
  • Likes Given: 604
Moving on, here's a whole new off-the-wall idea.

I'm actually surprised no one has mentioned it yet, I cannot imagine I'm the first to think of it:

A Hollywood Studio for filming actors in a weightless environment.

Was already proposed; several people also guessed that porn industry will be interested. IMHO, if porn industry can be used to finance space development, I have nothing against it.

Offline spacester

  • Member
  • Full Member
  • ***
  • Posts: 332
  • Liked: 41
  • Likes Given: 178
Moving on, here's a whole new off-the-wall idea.

I'm actually surprised no one has mentioned it yet, I cannot imagine I'm the first to think of it:

A Hollywood Studio for filming actors in a weightless environment.

Was already proposed; several people also guessed that porn industry will be interested. IMHO, if porn industry can be used to finance space development, I have nothing against it.

We Internet Fan-Boys have an annoying habit of saying "Hey, it's easy, just do (X) and we'll all have (Y)!" Yet nothing is easy in spaceflight.

I try to not fall into that trap, but seriously, this one really does seem that easy. Given the capability of a Bigelow module and the other systems needed to make it a full-fledged space station, along with getting people and equipment there and back, I don't see much more needed than a green screen interior. I wonder what I am missing?

As far as porn goes, it seems clear that it will happen "a few minutes after it becomes profitable". That's a different market than Hollywood blockbuster territory, however. And Mr. Bigelow strikes me as a guy who would not want his brand cheapened in that way. (Totally guessing here.)

But I'm with you, go for it fellas! Just expect that you will need to keep it under the radar as much as possible to prevent a backlash from the moralists among us.

Offline A_M_Swallow

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 8906
  • South coast of England
  • Liked: 500
  • Likes Given: 223
I try to not fall into that trap, but seriously, this one really does seem that easy. Given the capability of a Bigelow module and the other systems needed to make it a full-fledged space station, along with getting people and equipment there and back, I don't see much more needed than a green screen interior. I wonder what I am missing?

Cost.  Not many films can afford $200 million to get the actors and crew into space just to film 1 scene.

Offline spacester

  • Member
  • Full Member
  • ***
  • Posts: 332
  • Liked: 41
  • Likes Given: 178
Well of course the idea would be to spread the cost over several movies and other uses of the same module. And where do you get the idea it would only be one scene?

$200M seems a bit exaggerated, and 1/10th of that would seem to be within the budget of a Hollywood blockbuster. The production company would not be buying the thing, just leasing it for the duration of the filming.

What's our best estimate of the cost to transport a crew of six to the station and back on, say Dragon or CST-100?


Offline Pedantic Twit

  • Full Member
  • *
  • Posts: 102
  • Liked: 7
  • Likes Given: 0
Which is cheaper?

  • Filming on Earth and hanging everything from wires.
  • Filming on a parabolic flight and dealing with the small sets.
  • CGI.
  • Sending a film crew and actors into space.

    Inception had several microgravity scenes (as well as several with wonky gravity and impossible geometry) and yet they managed to do it all on Earth with real sets, a reasonable budget and excellent results.
  • « Last Edit: 11/14/2010 02:53 am by Pedantic Twit »

    Offline Patchouli

    • Senior Member
    • *****
    • Posts: 4490
    • Liked: 253
    • Likes Given: 457
    Which is cheaper?

  • Filming on Earth and hanging everything from wires.
  • Filming on a parabolic flight and dealing with the small sets.
  • CGI.
  • Sending a film crew and actors into space.

    Inception had several microgravity scenes (as well as several with wonky gravity and impossible geometry) and yet they managed to do it all on Earth with real sets, a reasonable budget and excellent results.

  • Parabolic flight was used in some of the more realistic space movies such as Apollo 13.

    I can see them also filming on sub orbital vehicles once some large enough enter service.

    Sub orbital flight also would be a near term option that likely would be well within the budget of a block buster type production.
    « Last Edit: 11/14/2010 03:12 am by Patchouli »

    Offline A_M_Swallow

    • Elite Veteran
    • Senior Member
    • *****
    • Posts: 8906
    • South coast of England
    • Liked: 500
    • Likes Given: 223

    $200M seems a bit exaggerated, and 1/10th of that would seem to be within the budget of a Hollywood blockbuster. The production company would not be buying the thing, just leasing it for the duration of the filming.

    What's our best estimate of the cost to transport a crew of six to the station and back on, say Dragon or CST-100?

    NASA is paying SpaceX $1.6 billion for 12 flights to the ISS.
    http://www.spacex.com/dragon.php

    $1,600M / 12 = $133.33M + cost of stay in spacestation

    Offline spacester

    • Member
    • Full Member
    • ***
    • Posts: 332
    • Liked: 41
    • Likes Given: 178
    Which is cheaper?

  • Filming on Earth and hanging everything from wires.
  • Filming on a parabolic flight and dealing with the small sets.
  • CGI.
  • Sending a film crew and actors into space.

    Inception had several microgravity scenes (as well as several with wonky gravity and impossible geometry) and yet they managed to do it all on Earth with real sets, a reasonable budget and excellent results.

  • Parabolic flight was used in some of the more realistic space movies such as Apollo 13.

    I can see them also filming on sub orbital vehicles once some large enough enter service.

    Sub orbital flight also would be a near term option that likely would be well within the budget of a block buster type production.


    (end quote, weird malfunction here)

    OK fine if you guys want to be practical and everything, lol.

    One thought was that having a large set with full-time micro-gravity would let a visionary filmmaker do things that couldn't be done before with those methods. When I've seen "the making of" programs they go on and on about how difficult it was to get their shots in intervals of, what, less than 30 seconds. A Bigelow module studio would for the first time allow for extended scenes with authentic weightlessness.

    I have to admit that CGI will be increasingly hard to compete with.

    The other thought was that at least the first production or two done on orbit would have the potential to be wildly popular just because of the first-ness of it.

    And hey, I didn't start the topic. LOL
    « Last Edit: 11/14/2010 04:16 am by spacester »

    Offline Nathan

    • Member
    • Full Member
    • ****
    • Posts: 710
    • Sydney
    • Liked: 16
    • Likes Given: 3

    $200M seems a bit exaggerated, and 1/10th of that would seem to be within the budget of a Hollywood blockbuster. The production company would not be buying the thing, just leasing it for the duration of the filming.

    What's our best estimate of the cost to transport a crew of six to the station and back on, say Dragon or CST-100?

    NASA is paying SpaceX $1.6 billion for 12 flights to the ISS.
    http://www.spacex.com/dragon.php

    $1,600M / 12 = $133.33M + cost of stay in spacestation

    NASA is also paying for data sets. Removing this will reduce the cost. Also, reflying each capsule will reduce costs since one is not purchasing a fresh capsule each time.
    Flight per person would be below $20m.
    Given finite cash, if we want to go to Mars then we should go to Mars.

    Tags:
     

    Advertisement NovaTech
    Advertisement Northrop Grumman
    Advertisement
    Advertisement Margaritaville Beach Resort South Padre Island
    Advertisement Brady Kenniston
    Advertisement NextSpaceflight
    Advertisement Nathan Barker Photography
    1