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Online Comics => Escape From Terra => Topic started by: Plane on December 02, 2010, 08:07:52 pm

Title: Industry in Space
Post by: Plane on December 02, 2010, 08:07:52 pm
Lets discuss industrys that might benefit from the environment of space.


(1)Replacement organs.
  The direction of present research is to use scaffolds that guide the formation of cells.

  In a microgravity environment this scaffold would not need to be substantial or strong, it could be a very flimsy aerogell that would not interfere with the function of the organ after it is finished and installed.

(2) Ball bearings

      In a zero gravity vacuum getting a ball bearing to be nice and round would be pretty easy, it might not even be hard to make them of exotic materials or to form them of layers of diffrent materials.  I speculate that they could even be made hollow, tiny or huge with less problem than manufacture on earth would allow..



Title: Re: Industry in Space
Post by: colonist on December 03, 2010, 02:13:26 am
Good idea. I will see you and raise you:

(3) Metalworking:
 Without gravity to cause separation some really exotic combination's could be explored (think aluminum/tungsten) and massive sheets and even whole structures could be made from foamed metals.
Title: Re: Industry in Space
Post by: Apollo-Soyuz on December 03, 2010, 06:18:03 am
Vacuum tubes. Vacuum is everywhere and free and very high quality. 

I'm trying to remember the name of the article about space industry I read years ago in Analog or something.

There's this Wikipedia page http://en.wikipedia.org/wiki/Space_manufacturing
Title: Re: Industry in Space
Post by: libertymonkey on December 03, 2010, 04:00:52 pm
Here are some thoughts on good, old-fashioned low-tech manufacturing in space:

Scrap aluminum must have no moisture before it is melted to avoid explosive reactions.  The cost of putting thermal energy in to boil off any moisture could be eliminated by shredding the scrap in a cheap vacuum to boil off any moisture.

Hot-rolled steel builds up rust so thick and nasty it is called scale and it must be de-scaled and pickled (hot acid bath) before it can be cold rolled.  I imagine casting and hot-rolling steel in an oxygen-free vacuum would eliminate this expense.

Cold-rolled (non-stainless) steel will rust in an oxygen environment.  If it must be annealed to relax the grain structure after cold-rolling (anything that will be drawn and formed must be), it must be annealed within a short period of time to avoid rust.  A non-oxygen vacuum would allow more flexibility.

Steel and aluminum annealing uses hydrogen gas for heat transfer characterics.  Unfortunately, hydrogen reacts violently with oxygen at high temperatures.  So first the atmosphere is purged with nitrogen, then the nitrogen replaced by hydrogen, then heat applied for time, then purge the hydrogen with nitrogen, then introduce normal atmosphere to extract the coils of steel or aluminum.  The nitrogen purging would not be needed in a vacuum environment.

After the steel is tempered for final metallurgical properties, it is often coated in oill to prevent rust, but must be cleaned before paint is applied.  Both coating and cleaning steps would not be needed for many products.

Lastly, many small object, high quantity manufacturing processes (such as bottling) use 3-dimensions in a facility as much as is practical in facilities here (limited by ability to access the equipment).  A given manufacturing facility could better use a given volume if gravity were not a factor.  Also, most mass bottling uses centrifugal fillers, so a lack of gravity would not be a problem.

I think I spend way too much time in manufacturing facilities.
Title: Re: Industry in Space
Post by: ZeissIkon on December 03, 2010, 07:17:37 pm
(2) Ball bearings

      In a zero gravity vacuum getting a ball bearing to be nice and round would be pretty easy, it might not even be hard to make them of exotic materials or to form them of layers of diffrent materials.  I speculate that they could even be made hollow, tiny or huge with less problem than manufacture on earth would allow..

Part of this is a long-held myth.  It's neither easier nor more difficult to manufacture a steel (or other hard material) sphere to ball bearing tolerances (sub-tenth -- in machining terms, a "tenth" is .0001" or about .0025 mm -- tolerance for radius and roundness, surface finish of a few microinches = a few tens of nanometers) in microgravity; you don't just melt a lump of metal and let it cool, because you'll get a too-rough surface that's way, way out of tolerance for roundness and size; in either environment, you still have to go through a carefully controlled grinding and polishing regime to make a ball bearing that works (and trust me, making the races the balls run in isn't improved in microgravity, either).  I got this information, BTW, from something G. Harry Stine wrote around thirty-five years ago, so it isn't recently discovered...

The other part, about being able to more easily make hollow spheres for bearings, might well be true -- or it might not, though it'd certainly be simpler to make hollow spheres with vacuum inside when vacuum is plentiful and free (BTW, a suitably stiff and strong sphere filled with vacuum might make a nice substitute for lifting gas in an airship -- but it'd probably require a Fullerene to give a strength-to-weight ratio adequate to the task, even if you use spheres the size of sand grains).  In between, some exotic materials would be easier to work in vacuum -- titanium, for instance, which has to be worked under argon on Earth to avoid having the whole melt burn off with even a nitrogen blanket, never mind air at 21% oxygen -- while others would not; tin, zinc, silver, and a few other metals are referred to as "high vapor pressure" -- meaning they evaporate at a temperature relatively close to their melting point (interestingly, the metal most commonly evaporated, aluminum for coating mirrors, isn't in this class, but its low melting point and optical properties make it the top candidate).
Title: Re: Industry in Space
Post by: Plane on December 08, 2010, 12:24:32 am
Glass might be a good materiel for working in space.

Heat loss would be slow in a vacuum so applying heat and haveing a long time in plastic state would allow large glass items to be worked .

I am imagining a lump of molten glass the size of a mountain being melted by solar heat then blown into a very large sphereical bottle with heated gas.

The domes of classical sci-fi domed citys could be made like that , but they could only be deorbited onto small bodys like Ceries where it might be practical to thrust against the accelleration of its fall.

Glass can be made of very common materiels , mostly silica , but there are exotic formulas of glass that allow high strength and tempreture resistance, in a vacuume the heat loss that causes glass to harden and to temper could be controlled even over very large molten globs.

Here is something you can barely do on earth that might be simple on a small microgravity asteroid.> A tub of molten tin rotated in gravity forms a parabolic surface. The rotational speed vs the gravity strength determines the focal length of the resulting mirror.Accelleration  would work as well as gravity and would be adjustable. If vibration is damped the reflector is near perfect. Molten glass floats on molten tin and the face of the glass on the tin is very smooth. Cooling must be gradual. This process has been done on earth , but in space the limits of scale become rediculous.
Something like this simple process could be used to produce a telescope reflector of absolutely huge size and it could be set in a frame work telescope with very long focal length . Whatever you aimed this big eye at , you could get a really good look .

.
Title: Re: Industry in Space
Post by: Plane on December 08, 2010, 12:33:53 am
Quote
ZeissIkon.......Part of this is a long-held myth.  It's neither easier nor more difficult to manufacture a steel (or other hard material) sphere to ball bearing tolerances (sub-tenth -- in machining terms, a "tenth" is .0001" or about .0025 mm -- tolerance for radius and roundness, surface finish of a few microinches = a few tens of nanometers) in microgravity; you don't just melt a lump of metal and let it cool, because you'll get a too-rough surface that's way, way out of tolerance for roundness and size; in either environment, you still have to go through a carefully controlled grinding and polishing regime to make a ball bearing that works .....

I had envisioned just melting a measured amount of materiel and setting it adrift to gradually cool. I imagine that the formation of grains might produce a rough surface . or that a cristal form might produce a polyhedron rather than a sphere , grinding processes in a microgravity could produce a gritty mess that would be hard to controll , Is this indeed an example of a process that is easyer with gravity than without?
Title: Re: Industry in Space
Post by: Thaago on December 14, 2010, 01:18:30 am
Another very cool technology that works better in vacuum is electron beam deposition manufacturing, where an electron beam is used to boil materials off a source block and deposit them on a substrate, building multilayer 3-d objects. The velocities are high enough that gravity doesn't matter (much), but cheap vacuum would be great. The process has silly precision in the lab already (embedding nano-wires, etc.), could be used in a future setting like this to literally spray microchips. Or spaceships.
Title: Re: Industry in Space
Post by: Plane on December 14, 2010, 09:10:17 pm
Another very cool technology that works better in vacuum is electron beam deposition manufacturing, where an electron beam is used to boil materials off a source block and deposit them on a substrate, building multilayer 3-d objects. The velocities are high enough that gravity doesn't matter (much), but cheap vacuum would be great. The process has silly precision in the lab already (embedding nano-wires, etc.), could be used in a future setting like this to literally spray microchips. Or spaceships.

I like this one , the potential for building large scale is interesting.

A spaceship or station could be based on a fractal design and wind up with an organic shape from a building machine that could spray it together. Once the design was worked out for a unit and the transition and repeating pattern a relitively small building machine could turn out a ship or station of any size.


It might wind up looking like a broccali but that is allright too.
Title: Re: Industry in Space
Post by: libertymonkey on December 20, 2010, 11:31:20 am
More fantastically boring low-tech industrial potential in space:

When an electrical circuit is interrupted, an inductive (magnetic fields, i.e. motors) load does not like to have its current interrupted.  It has 'inertia', for lack of a better layman's term.

At higher power levels, the electrical current in the air will superheat the air into plasma, and then the electrons can flow freely from atom to atom, just like in a metal.  At those sustained temperatures, the copper conductors will vaporize and violently expand.  Once this occurs, it feeds itself violently until something happens to end it (an upstream breaker, the resulting explosion extinguishes the arc, etc.).

Medium and High voltage switchgear extinguish the arc of opening a circuit under load by a variety of methods:  opening contacts in a vacuum bottle (no air to turn into conductive plasma), using a magnetic field to exert an electromagnetic force on the current flowing in the air to make the arc too long to be self-sustaining, using a blast of air to dissipate the conductive plasma, opening contacts in an inert gas (no free electrons to ionize into a plasma), or opening contacts in oil (no free electrons to ionize into a plasma, and no free oxygen to combust the oil at temperature).

Anyway, the vacuum bottle circuit bottles are vulnerable to the integrity of the vacuum bottle and sealing diaphragms in a high vibration industrial environment.  In an environment with cheap vacuum, the cost of safely distributing electrical power would be drastically reduced.
Title: Re: Industry in Space
Post by: ZeissIkon on December 20, 2010, 04:07:48 pm
Quote
ZeissIkon.......Part of this is a long-held myth.  It's neither easier nor more difficult to manufacture a steel (or other hard material) sphere to ball bearing tolerances (sub-tenth -- in machining terms, a "tenth" is .0001" or about .0025 mm -- tolerance for radius and roundness, surface finish of a few microinches = a few tens of nanometers) in microgravity; you don't just melt a lump of metal and let it cool, because you'll get a too-rough surface that's way, way out of tolerance for roundness and size; in either environment, you still have to go through a carefully controlled grinding and polishing regime to make a ball bearing that works .....

I had envisioned just melting a measured amount of materiel and setting it adrift to gradually cool. I imagine that the formation of grains might produce a rough surface . or that a cristal form might produce a polyhedron rather than a sphere , grinding processes in a microgravity could produce a gritty mess that would be hard to controll , Is this indeed an example of a process that is easyer with gravity than without?

Exactly -- crystal formation gives a rough surface as well as poorly controlled radius and roundness (look at shot-tower lead shot, if you can find any; that's about as smooth as microgravity ball bearings could get without grinding, though not quite as round).

Grinding isn't that hard to control; it's almost always done wet, that is, the abrasize is mixed with a liquid (water or an oil of some sort) that lets you handle it as a liquid, as well as trapping fresh and spent grit and removed work material.  In microgravity, that slurry would behave like any high density, high surface tension liquid: it would tend to stay stuck on surfaces unless there's significant force moving it (airflow, acceleration, or vibration), and if loose in air would then contract into globules (go find a video of astronauts playing with water in microgravity, then watch it at 1/10 speed to simulate a high density slurry) that are pretty easily collected by an actively controlled vacuum wand or by general airflow through an appropriate filter.  In an industrial setting, you'd have a grinding cell in which the slurry circulates, applied to the working surface by a tube and allowed to recirculate through the cell for collection -- there'd be no air in the cell, just slurry, and the computer controlling the process would use non-optical methods to control the process (as a first guess, industrial X-rays, high frequency sonic, or even electron tunneling probe systems might be usable to monitor smoothness, while radius control is easily designed into the machinery and requires little monitoring compared to surface finish).
Title: Re: Industry in Space
Post by: Plane on December 26, 2010, 03:47:09 pm
So a ball bearing plant in space would not have any particular advantage due to microgravity , nor any insurmountable disadvantage either.

What of larger spheres?

Would there be a simple method of makeing a sphere or sphereical flask of a very large size with no molds if a glob of molten materiel were set adrift? Some Meteorites have a particular grain pattern that might be the result of cooling in little or no gravity. I think that meatals that were blown into large bubbles could be brought together to form compartmented shapes as do soap bubbles, the face between two soap bubbles is always flat. If the cooling rate were controllable the grain pattern might make the hardness and toughness of the resulting meatal shape controllable.

http://www.amnh.org/exhibitions/permanent/meteorites/planets/crystals.php

Irridium is more common in asteroids than in the earths crust, this is a valuable and dureable metal would the alloys of space manufacture be diffrent formulas than earth made because of diffrent availibility of alloying materiels?
Title: Re: Industry in Space
Post by: Plane on December 26, 2010, 03:49:18 pm
If I were building a building on a moon of Saturn I might want to build big and the materiel of choice might be water.

There is a lot of water in that neighborhood but its normal state is solid, in the light gravity a steel framed building with an ice skin could be tremendous.
Title: Re: Industry in Space
Post by: Holt on January 01, 2011, 08:53:41 am
The artificial organs one. The scaffold wouldn't interfere with the organs function anyway as the scaffold is taken from an organ by removing all the currently living cells from it. You effectively take a useless example of the organ, strip the cells and apply new ones to the sanitised scaffold.
Title: Re: Industry in Space
Post by: Plane on January 01, 2011, 04:46:26 pm
The artificial organs one. The scaffold wouldn't interfere with the organs function anyway as the scaffold is taken from an organ by removing all the currently living cells from it. You effectively take a useless example of the organ, strip the cells and apply new ones to the sanitised scaffold.


This is present tecnology , but this still requires a donor organ doesn't it?  With all of the liveing cells removed what is left ? a sac of organic connective tissues?


What if you could cast an aerogell scaffold and infuse it with appropriately hormone triggered cells of the recipient?


The materiel would have to be appropriate to the use , but whatever it was it could be very lightweight it it was in low gravity.


The scaffolds might be made in a 3d printer , especially if the result didn't need the structural strength to support its own weight. Organs might become availible and cheap enough to make extreme lifespans ordinary.
Title: Re: Industry in Space
Post by: Holt on January 01, 2011, 05:46:39 pm
The artificial organs one. The scaffold wouldn't interfere with the organs function anyway as the scaffold is taken from an organ by removing all the currently living cells from it. You effectively take a useless example of the organ, strip the cells and apply new ones to the sanitised scaffold.


This is present tecnology , but this still requires a donor organ doesn't it?  With all of the liveing cells removed what is left ? a sac of organic connective tissues?


What if you could cast an aerogell scaffold and infuse it with appropriately hormone triggered cells of the recipient?


The materiel would have to be appropriate to the use , but whatever it was it could be very lightweight it it was in low gravity.


The scaffolds might be made in a 3d printer , especially if the result didn't need the structural strength to support its own weight. Organs might become availible and cheap enough to make extreme lifespans ordinary.

We may well be able to print the scaffolds in gravity. I'm not sure it's something that would benefit enough from microgravity to make it worth the effort.
Title: Re: Industry in Space
Post by: Plane on January 01, 2011, 07:05:50 pm
The artificial organs one. The scaffold wouldn't interfere with the organs function anyway as the scaffold is taken from an organ by removing all the currently living cells from it. You effectively take a useless example of the organ, strip the cells and apply new ones to the sanitised scaffold.


This is present tecnology , but this still requires a donor organ doesn't it?  With all of the liveing cells removed what is left ? a sac of organic connective tissues?


What if you could cast an aerogell scaffold and infuse it with appropriately hormone triggered cells of the recipient?


The materiel would have to be appropriate to the use , but whatever it was it could be very lightweight it it was in low gravity.


The scaffolds might be made in a 3d printer , especially if the result didn't need the structural strength to support its own weight. Organs might become availible and cheap enough to make extreme lifespans ordinary.

We may well be able to print the scaffolds in gravity. I'm not sure it's something that would benefit enough from microgravity to make it worth the effort.


I am not certain either, but I would love to be the guy that came up with the idea that makes trips into space financially rewarding.

Research into replacement organ manufacture will continue if I ignore it , I am not worried, but there is a wisdom in  a large number of people , like parrellel processors , brainstorming can winnow a huge number of ideas and sometimes a combination of silly ideas turns into a practical winner.

There is a large barrier to makeing a profit in space and only a few uses have passed this barrier, this is the expense of lifting mass out of Earths gravity well. If an asteroid of pure gold weighing seven thousand pounds were to fall into the sun , passing within easy observation of Earth , it would not pay you right now to go get it or any part of it, it costs more per pound to match speeds with an asteroid from the Earth than gold is worth per pound.

There are things worth a lot more pound for pound than gold , replacement organs are one of these. but as you say I am NOT sure that zero G would make them better. I just would like to find something .