h a l f b a k e r yRight twice a day.
add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
If a large copper meshed rubber balloon were taken into space and then inflated, it could then be sprayed with alternating liquid plastic and hardener using a spray head inside the baloon.
This process could be repeated as many times as required, until the outside wall was strong enough to safely support
an atmosphere.
Getting an even coating would be achieved by creating different potentials within the balloon and attracting the plastic mist to the balloon's inner surface.this would be possible using electromagnetic attraction by making the mesh of the balloon an anode and the spray head a cathode.
The power for this would be supplied by a solar array.
Hope i got the anode and cathode the right way round or all i would get is a gumed up nozle.
Inflatable Space Station
http://www.bigelowa...out_there/index.php
[theircompetitor, Jul 15 2006]
inflatable spacecraft/station
http://science.hows...ble-spacecraft2.htm
HSW kicks ass [nomocrow, May 16 2007]
Foam Hulled Spacecraft
Foam_20Hulled_20Spacecraft
This old idea reminded me of this other, slightly less old idea. [bungston, May 16 2007]
one of my earlier posts...
Low_20budget_20spacecraft
[normzone, May 19 2007]
[link]
|
| |
But you still have to get it all into space. Also the baloon has to be strong enough to hold an atmoshepre to start with else it will burst before it is fully inflated. |
|
| |
True, the balloon would have to hold atmoshere, but only enough to make it form a shape. You could fill it with a tenth of a psi. Then as it got stronger, you could fill it with enough air that humans could breathe. |
|
| |
True you still have to ship up supplies, but with the supplies being a liquid you dont need as much space and with plastic being light in proportion to say steel, the payload is less. So a larger quantity of plastic resin and hardener could be transported.
The pressure of the ballon upon inflation would be minimal to conserve air and reduce the likely hood of failure due to high stresses, until the inner surface had hardened and was thick enough to support the pressures required.
After all any thickness could be made just keep on spraying. |
|
| |
This is very interesting + |
|
| |
In Neal Stephenson's Diamond Age, vacuum baloons were used to float a variety of objects. The technology assumed very light materials that would make such a construction buoyant. |
|
| |
In space construction, you want something with a high strength to weight ratio. Steel is nice, aluminum is better. carbon or kevlar fiber is great, but expensive. Plain unreinforced plastic is not all that great. |
|
| |
Possible solution: since this doesn't need to be done quickly, send up the balloon and a shipment of pre-impregnated (pre-preg) composite roving cord, along with a robotic cord laying device. Once the initial shell (thin layer of plastic covered with several inches of insulating and protective foam) is sprayed, put the robot inside and let it start laying cord. Once the cord is all in position, use a heating device (solar powered electric heating element?) to cure the shell. Once this is done, you're ready to start outfitting. |
|
| |
For small scale projects, it's probably more cost effective to just build it on earth and ship it up fully loaded, but for much larger scale endeavo[u]rs (such as something sufficiently large to spin up for artificial gravity) where pre-assembly of the large components isn't feasible, this might be a very viable solution. |
|
| |
Good idea; here's a freeze-dried croissant for you. |
|
| |
Sounds like a great idea. One worry, though, is that the plastic resin might not stand up well to radiation. |
|
| |
What will this plastic thing do when struck by a tiny bit of junk travelling at many thousands of miles per hour relative velocity? |
|
| |
Not a great idea. First, there are very few plastics that do not A) outgas, B) don't break down in UV, and C) and you can spray. |
|
| |
There would be a great difficulty actually spraying the material in a zero-g environment. While the +/- would help the material once it was in close proximity to the sphere, it would not evenly distribute the spray across an area. |
|
| |
As for weight, you would have to take up pressurized tanks of the stuff, requiring a lot of weight. If they were not pressurized, the material would not aerate and disperse over an area. And while the solid density of plastic is much less than steel, the liquid density would be much higher, maybe approaching 1/2 of steel. |
|
| |
Here is the flip side, the idea is a little baked. NASA has already flown inflatable space structures. They send it up, inflate with N2, and the polymer UV cures hard. Probably would be much easier to fly a big ball of this stuff than spray one out in orbit. |
|
| |
Could you not inflate the structure with an expanding foam?
It would pressurize evenly and then a central heat source could melt the foam into whatever size shell you want. Dripping and running won't be a problem, just make sure it has no spin.
You could then armor the inside. |
|
| |
Not presurised tanks but a pump much like a diesel pump injector arangement ,then there is no need for heavy presurised tanks, just light containers that the liquids could be pumped from.
Other solutions could also be used to line the inside, such as aluminum filings atracted to the inside of the sphere and then a flash melting system to coat the inside.
You would need to first spray a heat proof lining or the plastic would melt so you would have a sandwich of copper, then rubber, then plastic, then fire retardent, then aluminum, that should make it strong and long term viable. |
|
| |
I can't believe I'm reading about a zero-G diving bell. |
|
| |
See link. First module up and returning data. |
|
| |
[Lt_Frank] There would be no net force as the paint will hit the balloon. |
|
| |
Once you have built the spacestation, what would you do with it? You'd still have to fit it with all the other complicated crap that goes into a spacestation, which is much easier to do on the ground where wastage is not a problem and manpower is a cheaper resource. |
|
| |
[freefall] ...carbon or kevlar fiber is great, but expensive... |
|
| |
Everything is expensive in space. The cost of the material on Earth is a trivial part of the cost of the material in space - the cost in space is almost entirely the fuel cost of getting the stuff there, which is mostly proportional to the weight (with a small amount proportional to the volume, because voluminous payload needs a bigger craft, which weighs more). |
|
| |
//put the robot inside and let it start laying cord// |
|
| |
What was the science fiction story with the giant GM spiders that were used to reinforce a space station? |
|
| |
John Varley's "Golden Globes". |
|
| |
What was the one where they were torturing the benevolent alien to find out why they were keeping us in the dark about telekenesis? |
|
| |