Author Topic: Inspace repair hub  (Read 14311 times)

Offline A_M_Swallow

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Inspace repair hub
« on: 02/11/2014 09:57 pm »
The "Affordable habitats means more Buck Rogers for less money says Bigelow" thread strongly suggests that inspace repair hubs will be needed.  Ref http://forum.nasaspaceflight.com/index.php?topic=33965.0

The mental image I have is the space equivalent of a car repair garage in a village that is a long way from anywhere.

This thread is to allow discussion of what sort of repairs will be needed?  What repairs can be done inspace?  What facilities?  External arms?  Pressurized work rooms?  Unpressurized work rooms?  Space suits?  Large airlocks - able to pass a spaceship?  Small airlocks?  Docking and/or berthing ports?  Habitat for the crew?  Habitat for the crews of visiting ships?  What sort of tools?  Propellant depot to refuel ships?  Food shop to sell supplies to visiting ships?  Anything else?

Offline Jim

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Re: Inspace repair hub
« Reply #1 on: 02/11/2014 10:57 pm »
The idea is so far into the future, it is like a lump of clay.  It can be anything you want.   Until it is determined where the repair hub is and what types of vehicles it will service, the discussion is frivolous. 

Offline DMeader

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Re: Inspace repair hub
« Reply #2 on: 02/11/2014 11:43 pm »
What facilities?  External arms?  Pressurized work rooms?  Unpressurized work rooms?  Space suits?  Large airlocks - able to pass a spaceship?  Small airlocks?  Docking and/or berthing ports?  Habitat for the crew?  Habitat for the crews of visiting ships?  What sort of tools?  Propellant depot to refuel ships?  Food shop to sell supplies to visiting ships? 

Sounds like something out of the old Heinlein juvenile "The Rolling Stones".  Maybe they'll sell flat cats.
« Last Edit: 02/11/2014 11:49 pm by DMeader »

Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #3 on: 02/12/2014 01:20 am »
The Inspace Repair Hub for the LEO_to_LLO round trip would probably be in LEO.  It becomes needed when the first reusable manned tug flies.

Offline Jim

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Re: Inspace repair hub
« Reply #4 on: 02/12/2014 01:22 am »
It becomes needed when the first reusable manned tug flies.

No, they are not linked.  A reusable manned tug is not dependent on a repair hub, especially the first one.

Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #5 on: 02/12/2014 01:35 am »
It becomes needed when the first reusable manned tug flies.

No, they are not linked.  A reusable manned tug is not dependent on a repair hub, especially the first one.

I have heard of main rocket engines being lit 20 times.  Using a set of those may permit a reusable tug to do 10 round trips.  However are there any main engines that can do 20 full burns without any maintenance?

Offline Lar

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Re: Inspace repair hub
« Reply #6 on: 02/12/2014 02:08 am »
The idea is so far into the future, it is like a lump of clay.  It can be anything you want.   Until it is determined where the repair hub is and what types of vehicles it will service, the discussion is frivolous.

It's surely something that won't happen in the next few years. But this is advanced concepts... so gathering requirements is a useful exercise, and calving this thread off from the Bigelow thread was a good idea as well. Let's let this run for a while and see what comes of it. Folk not interested can ignore it.
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Offline Jim

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Re: Inspace repair hub
« Reply #7 on: 02/12/2014 02:14 am »

I have heard of main rocket engines being lit 20 times.  Using a set of those may permit a reusable tug to do 10 round trips.  However are there any main engines that can do 20 full burns without any maintenance?

Define main rocket engine, define round trip, define full burn.......

Some thrusters can fire 1000's of times and for scores of minutes.

You have to define your architecture (and include everything) not just the tug before you can make decisions on defining the hub.

It doesn't make sense to talk about a inspace repair hub at this time, just like it wasn't the right time to talk about gas/service stations in 1890's.


Offline darkbluenine

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Re: Inspace repair hub
« Reply #8 on: 02/12/2014 02:15 am »
The mental image I have is the space equivalent of a car repair garage in a village that is a long way from anywhere.

Similar concepts were studied early in the space station program, circa mid-80s.  Back then, the focus was not repair but either HST-like satellite servicing or assembly of human lunar or Mars mission stacks.  Here's one Encylopedia Astronautica entry to get you started if you want to research further:

http://www.astronautix.com/craft/spaedock.htm

My two cents is that these kinds of concepts have been overtaken or will be overtaken by Moore's Law, IVHM, and robotic servicing.  Only if/when there are radical reductions in the cost of getting and keeping humans in space does human servicing of spacecraft begin to make some sense.

Offline hop

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Re: Inspace repair hub
« Reply #9 on: 02/12/2014 02:19 am »
Related thread on pressurized repair spaces from a while back http://forum.nasaspaceflight.com/index.php?topic=26162.0

Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #10 on: 02/12/2014 01:08 pm »

My two cents is that these kinds of concepts have been overtaken or will be overtaken by Moore's Law, IVHM, and robotic servicing.  Only if/when there are radical reductions in the cost of getting and keeping humans in space does human servicing of spacecraft begin to make some sense.

Where ever the repair robots are kept becomes an inspace repair hub.

The alternative to repairing space craft is to launch expendable space craft.  Apollo used big expensive launch vehicles to launch its expendable space craft.

A repair hub may allow the space craft to be launched on an SLS.  After each flight say ~15% of the mass can be replaced using units brought up on cheaper LV.

Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #11 on: 02/12/2014 01:43 pm »

I have heard of main rocket engines being lit 20 times.  Using a set of those may permit a reusable tug to do 10 round trips.  However are there any main engines that can do 20 full burns without any maintenance?

Define main rocket engine, define round trip, define full burn.......
Quote

Main rocket engine(s) - the one(s) at the back that provide most of the delta-v.  As distinct from the RCS thrusters which are normally smaller and frequently on the sides.

Round trip - trip to a destination and back.  Definition from Harrap's English Dictionary.

Full burn - a burn that lasts a long time but hopefully but may be less than the maximum burn time for a single burn.


Some thrusters can fire 1000's of times and for scores of minutes.

You have to define your architecture (and include everything) not just the tug before you can make decisions on defining the hub.


Ah!  The nasty feed back loop in the requirements for most space equipment.

The initial design of the hub has to produced before the architecture can use it.  The final hub design needs to take requirements from the architecture.

Quote

It doesn't make sense to talk about a inspace repair hub at this time, just like it wasn't the right time to talk about gas/service stations in 1890's.

There were coaling stations for steam ships and trains in the 1890s.

If we choose to use reusable space craft then the hub could be used during the next but ~3 moon landing.
« Last Edit: 02/12/2014 01:44 pm by A_M_Swallow »

Offline darkbluenine

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Re: Inspace repair hub
« Reply #12 on: 02/12/2014 02:02 pm »
Where ever the repair robots are kept becomes an inspace repair hub.

If you examine today's commercial or DARPA satellite servicing proposals and projects, no one is planning to centrally locate or field their servicing spacecraft from a common hub or spacedock.  It's an unnecessary, additional cost.

Quote
The alternative to repairing space craft is to launch expendable space craft. 

Repairable is not the same thing as reusable.

Quote
Apollo used big expensive launch vehicles to launch its expendable space craft.

A repair hub may allow the space craft to be launched on an SLS.

Maybe a typo, but I don't follow the logic here.  If one HLV can mount human lunar missions without a repair hub, why can't another?

Quote
After each flight say ~15% of the mass can be replaced using units brought up on cheaper LV.

If you're saying that a repair hub is a way to get around an HLV like SLS, it's unnecessary.  Between AR&D, IVHM, and prop xfer, a spacedock is no longer necessary to assemble and checkout exploration stacks. 

In fact, I'm not sure that a spacedock was necessary to assemble exploration stacks back in the mid-80s when proposed for space station.  But you could at least go back to those studies to understand the reasoning and see if it still applies today.

FWIW...

Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #13 on: 02/12/2014 02:27 pm »
Where ever the repair robots are kept becomes an inspace repair hub.

If you examine today's commercial or DARPA satellite servicing proposals and projects, no one is planning to centrally locate or field their servicing spacecraft from a common hub or spacedock.  It's an unnecessary, additional cost.

Quote
The alternative to repairing space craft is to launch expendable space craft. 

Repairable is not the same thing as reusable.


Something that needs maintenance before it can be used again when no means of repairing it exists is no longer reusable.

Most current space hardware saves mass by being expendable.

Quote

Quote
Apollo used big expensive launch vehicles to launch its expendable space craft.

A repair hub may allow the space craft to be launched on an SLS.

Maybe a typo, but I don't follow the logic here.  If one HLV can mount human lunar missions without a repair hub, why can't another?


Apollo style architectures are too expensive for regular trips.

Quote

Quote
After each flight say ~15% of the mass can be replaced using units brought up on cheaper LV.

If you're saying that a repair hub is a way to get around an HLV like SLS, it's unnecessary.  Between AR&D, IVHM, and prop xfer, a spacedock is no longer necessary to assemble and checkout exploration stacks. 

In fact, I'm not sure that a spacedock was necessary to assemble exploration stacks back in the mid-80s when proposed for space station.  But you could at least go back to those studies to understand the reasoning and see if it still applies today.

FWIW...


No.  I allowed use of the SLS, just not every trip.

The village garage can refuel cars.
Cargo LV can lift propellant.

Offline darkbluenine

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Re: Inspace repair hub
« Reply #14 on: 02/12/2014 04:41 pm »
Most current space hardware saves mass by being expendable.

I dunno.  To the extent that most current space hardware is comsats, most current space hardware has all the lifetime it needs without a repair hub.  Expendable/repairable/reusable sort of misses the point when Moore's Law makes the development and launch of a new satellite more cost effective than continuing to limp along on an old satellite with outdated capabilities.

And again, in the narrow applications where salvaging old comsats makes sense, projects like DARPA Phoenix, MDA SIS, or ViviSat MEV don't have any need for a repair hub.

Quote
Apollo style architectures are too expensive for regular trips.

I violently agree.  But given the current and projected costs of human-rated space systems, I don't see how fielding and operating another human-rated space system (the repair hub) on top of the human-rated exploration stacks would ever reduce the cost of the overall human exploration architecture.

Quote
No.  I allowed use of the SLS, just not every trip.

Well then we're sunk right there.  There's no budget for a repair hub or anything else if we're blowing $20 billion on our launch vehicle development alone.  Akin's 39th Law and all.

Quote
The village garage can refuel cars.

But we don't need a garage to refuel cars.  Just a pump.  Or even just a barrel of gas and a rubber tube.

Same goes for space propellants.  We just need a tank (thermally managed for cryo propellants) and a transfer mechanism.  There's no need to put another structure, pressurized or not, and more astronauts with all their attendant needs in that loop.

Quote
Cargo LV can lift propellant.

Propellant is infinitely divisible and very low cost compared to actual space systems.  It should be launched on whatever LV offers the lowest cost per unit mass of payload, regardless of size.  The lowest cost LV is unlikely to be an HLLV, especially an STS-derived HLLV with a very low launch rate.

Offline DMeader

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Re: Inspace repair hub
« Reply #15 on: 02/12/2014 04:45 pm »
What orbit is it going to be in?

Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #16 on: 02/12/2014 04:49 pm »
Most current space hardware saves mass by being expendable.

I dunno.  To the extent that most current space hardware is comsats, most current space hardware has all the lifetime it needs without a repair hub.  Expendable/repairable/reusable sort of misses the point when Moore's Law makes the development and launch of a new satellite more cost effective than continuing to limp along on an old satellite with outdated capabilities.

And again, in the narrow applications where salvaging old comsats makes sense, projects like DARPA Phoenix, MDA SIS, or ViviSat MEV don't have any need for a repair hub.
{snip}

I was not planning on repairing satellites.  Son of LEMs possibly.

Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #17 on: 02/12/2014 04:53 pm »
What orbit is it going to be in?

That depends on where we are going.  The first one will probably be in LEO, with EML-2 and LLO as other possible orbits.

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Re: Inspace repair hub
« Reply #18 on: 02/12/2014 05:02 pm »
What orbit is it going to be in?

That depends on where we are going.  The first one will probably be in LEO, with EML-2 and LLO as other possible orbits.

Until that is determined and for what reasons, there can be no real discussion on the configuration of such a hub, or even the need for one.

Offline darkbluenine

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Re: Inspace repair hub
« Reply #19 on: 02/12/2014 06:29 pm »
I was not planning on repairing satellites.  Son of LEMs possibly.

But wouldn't we just repair reusable landers on the Moon?  As long as we've got a lunar surface infrastructure  large enough require enough landers/landings to begin thinking about things like repair hubs, wouldn't we just locate that repair hub on the Moon to leverage that infrastructure?  Why create a space station to repair landers when we already have a space station on the Moon that could repair those landers?

There would be some penalty to bringing lander parts and tools down the lunar gravity well.  But with people and all their attendant needs already supported on the Moon (and probably a local propellant source too), that's probably more efficient than duplicating some of those people and supporting all their attendant needs somewhere in cislunar space.

My 2 cents.

Offline DMeader

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Re: Inspace repair hub
« Reply #20 on: 02/12/2014 07:08 pm »
What orbit is it going to be in?
The first one will probably be in LEO...

Well, which one? Which inclination? Without doing big plane change burns the station wouldn't be accessible to anyone not in that orbit. Are they going to build several of them?

Like Jim said, this whole scheme need a lot more thought. It did make for some neat images but so far that's all the good I see.

Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #21 on: 02/12/2014 10:19 pm »
What orbit is it going to be in?
The first one will probably be in LEO...

Well, which one? Which inclination? Without doing big plane change burns the station wouldn't be accessible to anyone not in that orbit. Are they going to build several of them?

Like Jim said, this whole scheme need a lot more thought. It did make for some neat images but so far that's all the good I see.

Which LEO orbit?  That is a much simpler problem.  The same LEO orbit as the launch site on Earth supplying the hub.

Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #22 on: 02/12/2014 10:22 pm »
What orbit is it going to be in?
The first one will probably be in LEO...

Well, which one? Which inclination? Without doing big plane change burns the station wouldn't be accessible to anyone not in that orbit. Are they going to build several of them?

Like Jim said, this whole scheme need a lot more thought. It did make for some neat images but so far that's all the good I see.

The lunar surface is a good place for a repair hub providing your lander flies back to LEO.  If the lander only flies to low lunar orbit or EML-2 then you need a second repair hub.

Offline Lar

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Re: Inspace repair hub
« Reply #23 on: 02/12/2014 10:27 pm »
I was not planning on repairing satellites.  Son of LEMs possibly.

But wouldn't we just repair reusable landers on the Moon?  As long as we've got a lunar surface infrastructure  large enough require enough landers/landings to begin thinking about things like repair hubs, wouldn't we just locate that repair hub on the Moon to leverage that infrastructure?  Why create a space station to repair landers when we already have a space station on the Moon that could repair those landers?

There would be some penalty to bringing lander parts and tools down the lunar gravity well.  But with people and all their attendant needs already supported on the Moon (and probably a local propellant source too), that's probably more efficient than duplicating some of those people and supporting all their attendant needs somewhere in cislunar space.

My 2 cents.

It depends on where the lander malfed. If it malfunctioned while not on the surface and it was something that would prevent a landing, no surface repair facility will help. if it malfunctioned while ON the surface, no orbital repair facility will help either.

Long term, steady state, (100 years from now?) there will be some repair facilities wherever there is a destination or transit point, just like today, airliners get repaired whereever they are. At least repaired enough to get them to their airlines hub where the main repair facility is. Even if they have to fly in mechanics and parts to effect the repair (I've been on airliners that were held waiting for a mechanic to come from the base)
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Offline Andrew_W

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Re: Inspace repair hub
« Reply #24 on: 02/12/2014 10:41 pm »
[snip]
It doesn't make sense to talk about a inspace repair hub at this time, just like it wasn't the right time to talk about gas/service stations in 1890's.

In the 1890's that would have been the blacksmith or the farrier.

If we see cislunar and translunar spacecraft with operational lifetimes of more than a single mission it'll make sense to at least give them the occasional spring clean and that would happen at one of their main terminals,  probably initially at the one closest to Earth. If a broken widget needs replacing, it'll be cheaper to replace it than replace the entire spacecraft, repairs aren't limited to stuff buried deep inside a rocket engine.
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Offline cordwainer

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Re: Inspace repair hub
« Reply #25 on: 02/13/2014 05:05 am »
I would point out that there is a point of diminishing returns when it comes to maintaining an independent "repair tug". You either have to continuously launch and recover a "reusable tug", or you do have to have some kind of repair and maintenance infrastructure in space to maintain an "orbital tug".
I would imagine that if your going to have manned habitats and space stations for other reasons like scientific research and space tourism you might as well marry that concept to a "tug maintenance station".

Personally, I think the way to go about it would be to use heavy lift to place fuel and spare parts in "parking orbits" from which tugs would pull what they need to repair or move satellites. Manned repair stations would be used for more delicate "depot level" repairs that cannot be carried out by simply plug and play of COTS modules. This would include high level repairs to both tugs and satellites. That being said there is the argument that it might be cheaper to go with simpler, cheaper expendable spacecraft rather than trying to increase the service life of "legacy equipment" satellites. My opinion is that making satellites with more common standards and modular designs would be better in the long run than expendables, since you could improve the satellite over time with the replacement or addition of new modules instead of designing a whole new satellite with independent propulsion, navigation and shielding systems that will for the most part not have to change for decades to come.

Offline clongton

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Re: Inspace repair hub
« Reply #26 on: 02/13/2014 02:01 pm »
In-space repair hubs are a long way off in the future. But it is an interesting exercise in speculation.

FWIW, in my opinion spacecraft of the future will be designed as in-space only vehicles, designed for multiple uses.
As such they will be designed to be repaired from the inside, not the outside, where shirt-sleeve environments are the normal condition. Outside repairs will be conducted in a manner similar to what occurs on ISS today, but these will be rare imo. I can envision a cage-like structure where the vehicle will be "docked" and secured. The facility will have normal crew accommodations and appropriate "shops" for repair and/or fabrication of components that will then be brought aboard the ship thru normal airlocks for installation from the inside.

Forgive the attached image please. I provide it solely for the purpose of displaying the concept of a space dock, which is what this facility would be.
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Offline cordwainer

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Re: Inspace repair hub
« Reply #27 on: 02/14/2014 01:18 am »
In the far future I imagine spacecraft will be largely modular, so a space dock may not be necessary. Modules will be removed and repaired elsewhere. Repairs and production of replacement modules will occur via ISRU on a lunar or small planetary body that doesn't require a lot of energy to lift modules to the spacecraft in need of repair. It is actually the near future that has more need of a in-space repair facility for the long term maintenance of orbiting satellites.

Offline JasonAW3

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Re: Inspace repair hub
« Reply #28 on: 02/24/2014 07:33 pm »
In the far future I imagine spacecraft will be largely modular, so a space dock may not be necessary. Modules will be removed and repaired elsewhere. Repairs and production of replacement modules will occur via ISRU on a lunar or small planetary body that doesn't require a lot of energy to lift modules to the spacecraft in need of repair. It is actually the near future that has more need of a in-space repair facility for the long term maintenance of orbiting satellites.

So, you're suggesting basicly a strongback , or keel as it were, upon which, control, habitat, cargo, landers, fuel and engines would be attached and intergrated like a space going lego set?  Interesting.

However, there would STILL be the need for repair workshops to maintenance and repair such modules, whether it be teh replacement of a spent nuclear core, repairing a rip or hole in an inflatible module or replacing corroded plumbing on a fuel tank.

A Repair hub will be needed, but whether or not it would be a pressurized environment would depend largely on the various chemicals used with the space craft.

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Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #29 on: 02/25/2014 12:05 am »
The big problem with pressurised areas is that if the air gets contaminated it has to be thrown away.  At more than $1000 a kilogram that gets expensive very quickly.

Reusable landers and transfer vehicles will have to be designed so that ~95% of the electronics and the ECLSS can be accessed from inside the spacecraft.  The parts can then enter and leave through the docking port.  I suspect that sea ships and submarines have a similar problem.

Offline JasonAW3

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Re: Inspace repair hub
« Reply #30 on: 02/25/2014 07:13 pm »
The big problem with pressurised areas is that if the air gets contaminated it has to be thrown away.  At more than $1000 a kilogram that gets expensive very quickly.

Reusable landers and transfer vehicles will have to be designed so that ~95% of the electronics and the ECLSS can be accessed from inside the spacecraft.  The parts can then enter and leave through the docking port.  I suspect that sea ships and submarines have a similar problem.

In theory, contaminates can be filtered, but you're talking a LOT of airflow, or hoses brought over to a work area specificly to suck in any sort of contaminate leak.

As to ships and seagoing vessels, mostly true, but there are times where they have to be dry docked for major maintenance.  (Hull scraping and painting, corrosion repair, hull lengthening, etc.)

A modular craft wouldn't have quite so much of a problem, but would still require some things to be done in a pressurized environment.

Jason
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Offline IRobot

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Re: Inspace repair hub
« Reply #31 on: 02/25/2014 08:50 pm »
You can still find use in a non pressurized closed repair hub. Better protection for EVA's, good lighting, stable suit temperature, no loss of tools, probably 360º access for multiple machinery on robotic arms, for example a in site CNC or 3D printing over a standstill spacecraft.

Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #32 on: 02/26/2014 01:47 am »
A non pressurised repair hub may be able to replace a fuel tank.  It may even be able to repair a hole using welding.

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Re: Inspace repair hub
« Reply #33 on: 02/26/2014 05:37 pm »
The idea is so far into the future, it is like a lump of clay.  It can be anything you want.   Until it is determined where the repair hub is and what types of vehicles it will service, the discussion is frivolous.

Nahhhh.... You gotta believe. 

I've already designed the structure.  Apologies for the crude video.
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Offline Asteroza

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Re: Inspace repair hub
« Reply #34 on: 02/26/2014 10:18 pm »
Hrm, similar to that Skylon infrastructure station design.

Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #35 on: 02/27/2014 08:11 am »
Putting tracks on the frame inside the space hanger will permit 2 or 3 Mobile Servicing Systems (MSS) to repair visiting vehicles.  Money and time can be saved by using the same design of arms, mobile base systems and Dxtres as the ISS.  Aim to repair or replace 80% of the items on the outside of spacecraft.  If addition types of repairs will be useful the repair hub can be upgraded later.
https://en.wikipedia.org/wiki/Mobile_Servicing_System

Offline Jim

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Re: Inspace repair hub
« Reply #36 on: 02/27/2014 11:20 am »
Money and time can be saved by using the same design of arms, mobile base systems and Dxtres as the ISS.

Not really, a hub won't be built for at least a decade.  Much of the knowledge of the construction and design of the MSS will be lost, in addition, there will be parts obsolescence.  Any new build will cost as much or more than the original. 

Offline JasonAW3

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Re: Inspace repair hub
« Reply #37 on: 02/27/2014 07:56 pm »
Money and time can be saved by using the same design of arms, mobile base systems and Dxtres as the ISS.

Not really, a hub won't be built for at least a decade.  Much of the knowledge of the construction and design of the MSS will be lost, in addition, there will be parts obsolescence.  Any new build will cost as much or more than the original.

Not quite sure I can agree with you on this one Jim.

Assuming, for the sake of argument, you start with, using the ISS as your base assembly point, you'd need essenitally a simple "Tent Frame" structure and a fabric covering.  (Similar to the Shuttle blankets for temperature regulation and micrometeoroid mitagation purposes).  Inside, you could attach movable Arm attachment points to allow arms to "Inch worm" their way to where they are needed within the frame.

The Tent frame would be based upon the systems tested on previous shuttle flights.  The arms could be modified Canada arms, (Which we have a few lying about right now)  Assuming a coverage enough to handle 4 Dragons, trunks and upper stages, placed in a four pack configuration, (For volume purposes only)  Such a structure could be manufactored in about a year, with parts and cover, sent up on 2 Falcon 9 flights, (Non-Dragon, simply payload) mostly assembled via robotic arms, and the cover could be attached in about 4 EVA's with Zip Ties, if need be.

Remote lights, cameras and handholds could be attached via clamps to the "Tent Frame" as needed.

Total time needed from budgeted money to final assembly, including training, testing fabrication and launch approximately 3 years.  Note, this would be ONLY for the unpressurized work area, in theory, a BA-2200 work shack could be assembled, tested and launched on a Falcon Heavy at about the same time, assuming parallel construction.

As tech changes and improves, parts of this system would be swapped out as needed, but the basic structure wouldn't really need that much alteration, unless it is to expand it's capibility.

Jason
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Offline Jim

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Re: Inspace repair hub
« Reply #38 on: 02/27/2014 08:37 pm »
Money and time can be saved by using the same design of arms, mobile base systems and Dxtres as the ISS.

Not really, a hub won't be built for at least a decade.  Much of the knowledge of the construction and design of the MSS will be lost, in addition, there will be parts obsolescence.  Any new build will cost as much or more than the original.

Not quite sure I can agree with you on this one Jim.


The MSS is the arm and its mobile base on the ISS

Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #39 on: 02/27/2014 09:06 pm »
Most silicon chip families are made for about 10 years.  I have seen a chip stay in the sales brochures for longer, its description mentioned NASA.

The electronics for the arm and MSS will have gone obsolete years ago, so the circuit boards will need redesigning to meet the same interfaces.  The blue prints for the mechanical parts may be on file somewhere.

The main aim of using the original designs is to keep the manufacturing time down to 3 years rather than the 10 years development time projects can take.

Offline Roy_H

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Re: Inspace repair hub
« Reply #40 on: 02/27/2014 10:31 pm »
Any new build will cost as much or more than the original.

Yeah, like taking the tank, SRBs, and motors from the Shuttle and spending $5B to re-arrange them into the SLS. Probably more than the original money to design and build those parts.
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Offline Jim

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Re: Inspace repair hub
« Reply #41 on: 02/28/2014 11:29 am »
The blue prints for the mechanical parts may be on file somewhere.

The main aim of using the original designs is to keep the manufacturing time down to 3 years rather than the 10 years development time projects can take.

Not available for anybody to use.  Only the original manufacturer and they might not be around.

Not feasible, it still will be a development project, since nothing can be reused. 

Offline JasonAW3

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Re: Inspace repair hub
« Reply #42 on: 02/28/2014 06:06 pm »
Money and time can be saved by using the same design of arms, mobile base systems and Dxtres as the ISS.

Not really, a hub won't be built for at least a decade.  Much of the knowledge of the construction and design of the MSS will be lost, in addition, there will be parts obsolescence.  Any new build will cost as much or more than the original.

Not quite sure I can agree with you on this one Jim.


The MSS is the arm and its mobile base on the ISS

Thank you for that Jim.

It would likely require aditional track to be set up to connect the Repair Hub, (Tent, whatever) to the ISS so the MSS could move into the Hub, along with its' mobile base.  But this is known technology, that can be reproduced and put into place. (Yes an extention to the electrical system would also be required, but this is know off the self tech that should be low mass enough to add to teh two flights.
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Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #43 on: 03/01/2014 09:38 pm »
A repair hub is definitely a development project, there has not been one before.  Using existing designs for as many parts as possible reduces the risk, cost and timescales.  Finding out what is still available would be part of the detailed costing process.

Offline A_M_Swallow

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Re: Inspace repair hub
« Reply #44 on: 03/04/2014 02:48 am »
The idea is so far into the future, it is like a lump of clay.  It can be anything you want.   Until it is determined where the repair hub is and what types of vehicles it will service, the discussion is frivolous.

Nahhhh.... You gotta believe. 

I've already designed the structure.  Apologies for the crude video.

In LEO the hub would be repairing transfer vehicles and space tugs.  In LLO and EML-1/2 the hub would be repairing reusable lunar landers.

It may be possible to use CubeSats to reduce the risk.  Launching requires the hub to fit into a fairing but to contain a spaceship it needs to be wider than a spaceship.  The proposed cure is to launch it flat and expand in space.  A CubeSat sized mini module that shows the opening and locking mechanism works can be built and launched cheaply.   A second satellite that contains a full sized joint can test that.

Offline JasonAW3

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Re: Inspace repair hub
« Reply #45 on: 03/04/2014 03:19 pm »
The idea is so far into the future, it is like a lump of clay.  It can be anything you want.   Until it is determined where the repair hub is and what types of vehicles it will service, the discussion is frivolous.

Nahhhh.... You gotta believe. 

I've already designed the structure.  Apologies for the crude video.

In LEO the hub would be repairing transfer vehicles and space tugs.  In LLO and EML-1/2 the hub would be repairing reusable lunar landers.

It may be possible to use CubeSats to reduce the risk.  Launching requires the hub to fit into a fairing but to contain a spaceship it needs to be wider than a spaceship.  The proposed cure is to launch it flat and expand in space.  A CubeSat sized mini module that shows the opening and locking mechanism works can be built and launched cheaply.   A second satellite that contains a full sized joint can test that.

Pretty much similar to what I'd envisioned as the "Tent Structure" sort of hub.  Theres a couple of expanding sphere designs that could work, similar to the "snowflakes" changing inti the Olympic rings that was tried during the Sochi opening ceremonies.  (Ony in 3d, not just 2d).
My God!  It's full of universes!

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