Author Topic: Realistic, near-term, rotating Space Station  (Read 254896 times)

Offline LMT

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Re: Realistic, near-term, rotating Space Station
« Reply #920 on: 07/13/2018 03:55 PM »
Considering an old post on tethered SpaceX AG:

I have changed my concept pic by reversing the spaceships so that radius is increased by length of the engine section. Note that this is opposite hanging direction as in ITS video so this may not be an improvement.




That scheme could be updated and adapted for a small 1-g LEO space station, offering good crew protection and economics.  One scenario:



Modules:

2 ITS cargo craft, each with 150 t of water.

2 ITS crewed craft, each with 150 t of crew and equipment, including a hub.

1 free-flying hub, with telescoping connectors to vertical-integration points near each cargo craft nose.

Deployment:

1.  Each cargo craft docks with a crewed craft.

2.  Water is transferred, distributed in a cushion-layer around crewed areas; cushion exceeding 40 cm thickness.

3.  Hub is deployed.  It connects cargo craft, completing a 200 m diameter station.

4.  Station rotates at 3 rpm for 1 g on outermost crewed compartment.

5.  Crew lives under 1 g and > 90% cosmic ray shielding.

Mods:

- A cargo tank and water transfer option would be added to the ullage system.   Possibly here a side-by-side water-transfer system would be needed, for simplified water piping.

- Cryogenic ullage connectors would be upgraded or else augmented to support ~ 3 MN weight.

- And of course the telescoping, free-flying hub would have to be created. 

- Other big mods?

Economic comparisons:

These mods seem modest, relative to de novo designs having same goals.  Has anyone run numbers on such a scenario, to compare the economics?

I wonder if SpaceX has designed the ITS with such a possibility in mind; e.g., building an ullage connector system with a surprisingly "robust" load capacity.  Any rumors to that effect?

Offline blasphemer

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Re: Realistic, near-term, rotating Space Station
« Reply #921 on: 07/13/2018 04:49 PM »
The other structure that has been discussed is to have a pressurised tunnel made from Bigelow-skin, with tensile cables running down the walls putting the tube under compression. Each component is strong enough to support the loads individually, but when you combine the tensile and compression elements, you get a much more rigid system.

As a bonus, you have a pressurised tube to transfer between modules (and repair the cables). Avoiding the "elevator", which would need to be a mini-spaceship, with two docking events for every trip.

That sounds interesting, could you point me to this discussion? Can we estimate how long can this tunnel be and still fit into BFS payload bay and mass limit? What would a good diameter be? The need to somehow cross vacuum and dock to get to the end modules irks me, too. The design would be so much easier if entire length can be pressurized.

Quote
5.  Crew lives under 1 g and > 90% cosmic ray shielding.

1g and low equatorial orbit is exactly what I had in mind. At 115m radius that is 2.79 RPM according to SpinCalc.

I dont want to reduce the diameter too much because I think the experience itself of building large structures in space that can rotate at 1g and not fall apart is an important function of such near-term station. Even ISS is 108 meters long, so it shouldnt be too unrealistic to build something 2-3 times as large in the longest dimension, if we have much more capable rockets than the Shuttle available.

I wonder about rotational stability, tough. Long sticks rotating around short axis are supposedly unstable. This could be a huge issue for this design.
« Last Edit: 07/13/2018 04:52 PM by blasphemer »

Offline Aussie_Space_Nut

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Re: Realistic, near-term, rotating Space Station
« Reply #922 on: 07/14/2018 03:06 AM »
That will learn me to leave an old thread favourite un-read for a while!

Loved reading the latest posts. Love your work mikelepage!

Thank you Nasaspaceflight  :)

A few points.

1) I'm not so sure the old Gemini experiment applies as the amount of AG was so small.
"Despite the oscillations in the tether and other spacecraft issues, these did settle down temporarily after 20 minutes or so, and for a brief time a teeny, tiny bit of artificial gravity was observed in the Gemini capsule. How much gravity? About 0.0005 g with 0.15 revolutions per minute. Some time later the tether was released." https://blogs.scientificamerican.com/life-unbounded/watch-the-first-artificial-gravity-experiment/

2) I like structures such as trusses. Nothing potentially flopping about in an emergency. (So long as the emergency is not greater than the load the truss can take of course.) I presume Mike's idea will lock in place after deployment.

3) I'm not so sure the guy with the bicycle wheel applies here. OK of course it does, but not in the rapid way it was demonstrated. Small adjustments over time, over a year, ought not to be a problem to maintain a certain orientation to the sun. (Assumption)

4) I started a thread in the moon section and as a part of it proposed an O'Neil Cylinder Cycler to get from the Earth to the Moon safe from radiation. It was to have AG and a "Moist Soil" radiation protection layer also used to grow crops. Then I did a mass calculation. Idea died right there. It was literally MASSIVE! So ridiculously heavy that it was just never going to happen this side of the year 3000 me thinks! :-)

5) One way to stabilise could be pumping fluids around.

6) Another way could be massive components such as the battery packs are made to move up and down the "spokes". Have 3 or 4 of them, their normal position is in the middle of the spoke, moving up and down very slowly as required. If they were also on arms they could very slowly rotate about the spoke as well. This way you get all axis control. (I think!)

Thanks again for getting me thinking!

Offline mikelepage

Re: Realistic, near-term, rotating Space Station
« Reply #923 on: 07/14/2018 09:05 AM »
That will learn me to leave an old thread favourite un-read for a while!

Loved reading the latest posts. Love your work mikelepage!

Thank you Nasaspaceflight  :)

A few points.

1) I'm not so sure the old Gemini experiment applies as the amount of AG was so small.
"Despite the oscillations in the tether and other spacecraft issues, these did settle down temporarily after 20 minutes or so, and for a brief time a teeny, tiny bit of artificial gravity was observed in the Gemini capsule. How much gravity? About 0.0005 g with 0.15 revolutions per minute. Some time later the tether was released." https://blogs.scientificamerican.com/life-unbounded/watch-the-first-artificial-gravity-experiment/

2) I like structures such as trusses. Nothing potentially flopping about in an emergency. (So long as the emergency is not greater than the load the truss can take of course.) I presume Mike's idea will lock in place after deployment.


Thanks for the kudos ASN! South Australia is a great place to be as far as Aussie space flight is going.  Hope you're keeping your ear to the ground, cause there are an increasing number of ways to get involved :)

Wish I could share what we're working on now (mechanical models), but I've already been told off by other co-founders for sharing too much :D  But I make an exception here because so much of my thinking has been shaped by the NSF forums!  Suffice to say I've re-attached a video of the model we used in the provisional patent - which, to answer your question, can potentially lock at any point during deployment.  This shows the basic concept of the Deployable Toroidal Array (DeTA), which we're currently raising $$ to patent/build further (cue plug to 3D model you can buy), but almost everything else has since been updated/simplified.

Long story short, I think if we use space origami concepts like the DeTA, we can entirely avoid using tethers and high spin rates (>6rpm), instead using solid/trussed structures which transform between two (or more) configurations.  One of the nice things about the way it folds out is that it is dynamically stable all the way through deployment - you could use the same structure for generating spin gravity on a planetary surface as you would in space.  Also, having a structure that can deploy and retract multiple times means you will always be to put the structure into a stable configuration for high g-force burns, supposing you want to attach rocket stages to change orbits quickly. 

Thinking about a notional human-scale DeTA spacecraft that could fit into the BFS payload bay - stowed configuration is roughly 17m long, 8.8m wide at the base, tapering to 5-6m at the top.  For that you get a deployed ~20m spin radius, and a torus of ~1.8m diameter modules all the way around (up to 2.2m if you allow a non-cylindrical cross section), plus 6 "vertical" tube/ladder modules (~1.4m wide) to the centre.  That's 4.2rpm for Mars g, or 6rpm for 0.8g.  Perfect for doing some serious human-scale partial-gravity studies whilst also being tolerable to the space tourism market.



side note: I've stopped using "AG" or artificial gravity in favour of "SG" or spin gravity.  I think it's more descriptive, and removes the sci-fi connotation of "creating" gravity fields, or whatever other techno-babble is employed in Star Wars/Trek/Gate etc.

« Last Edit: 07/14/2018 09:08 AM by mikelepage »

Offline blasphemer

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Re: Realistic, near-term, rotating Space Station
« Reply #924 on: 07/14/2018 10:33 AM »
New version of my realistic design is ready!



I added one more B330 module on each end, since it almost doubles pressurized 1g volume of the station for very little additional structure. I also added two smaller docking port modules on core module, one in each spin axis direction for redundancy. Total pressurized volume is now almost 1500 cubic meters, 1.5 times that of ISS. Length is 250 meters (ISS is 108 meters). I also added transversal trusses.

This is without pressurized tunnel connecting the core to the module, this I still plan to add. Can 95 meters of simple <2m diameter expandable tunnel fit into one BFS? With BFS payload bay being 15m long, this is an expansion factor of 6-7.

I estimate it should take a dozen BFR launches to construct this station, with launches being mostly volume rather than mass constrained.
« Last Edit: 07/14/2018 10:35 AM by blasphemer »

Offline spacenut

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Re: Realistic, near-term, rotating Space Station
« Reply #925 on: 07/14/2018 12:11 PM »
Instead of 1g spin, why not 0.4g spin to see what Mars conditions will do on the human body long term?  We know all about 0g, and soon we will probably be back at the moon with a moon base to check what moon gravity will do.  Spin would be less on the human body.  So instead of 2.9 spins per minute, it might get by with 1.5 or so.  Less dizziness effect on people, and test Mars gravity long term. 
« Last Edit: 07/14/2018 12:11 PM by spacenut »

Offline Paul451

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Re: Realistic, near-term, rotating Space Station
« Reply #926 on: 07/14/2018 12:29 PM »
I added one more B330 module on each end, since it almost doubles pressurized 1g volume

Errr, what is this for? We already have 1g pressurised volume. {waves hands around}

You would want gravity at different levels so you can research the effects of reduced gravity (between 0 & 1) on humans (and animals) to develop a better model of effects of long term missions/settlements on Moon/Mars. Also trying to find the minimum g-load that offsets the worst micro-g effects, so you have actual facts to use to assess if AG is worthwhile for interplanetary transport.

[Edit: Overlapped writing this with Spacenut saying the same thing.]

I dont want to reduce the diameter too much because I think the experience itself of building large structures in space that can rotate at 1g and not fall apart is an important function of such near-term station.

But not a "realistic" one. The people within NASA (and similar agencies around the world) who want AG research are not a dominant faction. Therefore any proposal needs to be small enough not to make waves. Larger than ISS, which was the major development program for two decades? No.
« Last Edit: 07/14/2018 12:29 PM by Paul451 »

Offline blasphemer

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Re: Realistic, near-term, rotating Space Station
« Reply #927 on: 07/14/2018 12:31 PM »
I guess you can use the station to test anything from 0g to 1g and if the structure is strong enough, even >1g gravities. Sometimes I wonder if living in high g environments would not offer health benefits similar to exercising..

New version:



Added simple pressurized tunnel, diameter is 1.4 meters (same as docking port), length is 97 meters or so. If that is too long then it would have to be launched in multiple segments or station length reduced. BFS for scale.

Offline blasphemer

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Re: Realistic, near-term, rotating Space Station
« Reply #928 on: 07/14/2018 12:51 PM »
But not a "realistic" one. The people within NASA (and similar agencies around the world) who want AG research are not a dominant faction. Therefore any proposal needs to be small enough not to make waves. Larger than ISS, which was the major development program for two decades? No.

I suppose future stations will take advantage of BFS, so making a large structure may still be significantly cheaper than ISS. Anyway, here is a more conservative design, then. Total length 104 meters, with only two Bigelow modules.

« Last Edit: 07/14/2018 12:52 PM by blasphemer »

Offline Coastal Ron

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Re: Realistic, near-term, rotating Space Station
« Reply #929 on: 07/14/2018 07:55 PM »
I added one more B330 module on each end, since it almost doubles pressurized 1g volume of the station for very little additional structure.

I don't understand this fascination with designing in zero-G components into micro-gravity structures. The Bigelow B330 is designed for zero-G only, and inflatables are not a good idea when you need to take structural loads.

Since the assumption is that any future artificial gravity space station will be constructed using New Glenn or BFS as transportation, it should be assumed that rigid modules can be constructed on Earth and launched complete, with final outfitting in space.

For instance, the BA330 is 6.7m in diameter when inflated, and New Glenn is 7m in diameter, so build an modular aluminum or carbon composite cylinder that can fit in a New Glenn or BFS fairing. Based on measurements I've made, New Glenn could carry a 6.7m diameter module that is close to 13m long, which matches up rather nicely with the 13.7m length of the B330. And two solid cylinders can be stacked far easier than two B330's.

Quote
I estimate it should take a dozen BFR launches to construct this station, with launches being mostly volume rather than mass constrained.

Which if the goal is to build the least expensive artificial gravity research station, this sounds pretty doable.

One thing to be aware of though is the Intermediate Axis Theorem. If you have a structure that is long in the X axis, and you attach something short on the Y axis, it could be induced to rotate between the Y and Z axis. Just an FYI...
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline Paul451

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Re: Realistic, near-term, rotating Space Station
« Reply #930 on: 07/14/2018 09:57 PM »
I added one more B330 module
The Bigelow B330 is designed for zero-G only, and inflatables are not a good idea when you need to take structural loads.

Why not? The walls can support at least 10 tonnes per square metre, a US ton per square foot. It's hardly a weak structure.

Offline mikelepage

Re: Realistic, near-term, rotating Space Station
« Reply #931 on: 07/15/2018 04:29 AM »
I added one more B330 module
The Bigelow B330 is designed for zero-G only, and inflatables are not a good idea when you need to take structural loads.

Why not? The walls can support at least 10 tonnes per square metre, a US ton per square foot. It's hardly a weak structure.

I think even Bigelow Aerospace has stopped using the term inflatable, in favour of expandable, to get away from the notion of a balloon which can pop.

The main advantage of expandables is the extra volume once inflated (The fairing for a BA2100 is only 8m wide) and better micrometeorite protection.

The main advantage of solid modules is that the on-orbit setup period is much reduced, because you already installed everything into the module while it was on the ground - including some facilities which might be impossible/very difficult to install in an expandable once on-orbit.

Offline Coastal Ron

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Re: Realistic, near-term, rotating Space Station
« Reply #932 on: 07/15/2018 06:09 AM »
I think even Bigelow Aerospace has stopped using the term inflatable, in favour of expandable, to get away from the notion of a balloon which can pop.

"popping" is not a concern with expandables/inflatables. They are designed for zero-G uses, so they are ill-suited for artificial gravity applications.

Quote
The main advantage of expandables is the extra volume once inflated (The fairing for a BA2100 is only 8m wide) and better micrometeorite protection.

The BA2100 is only a concept, and not even advertised on the Bigelow website. So let's focus on the requirements - how much space is needed to prove out at micro-gravity station?

Plus, with the availability of upcoming large-diameter launchers like the New Glenn and BFS, the need for expandables is reduced.

Quote
The main advantage of solid modules is that the on-orbit setup period is much reduced, because you already installed everything into the module while it was on the ground - including some facilities which might be impossible/very difficult to install in an expandable once on-orbit.

Agreed.
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline blasphemer

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Re: Realistic, near-term, rotating Space Station
« Reply #933 on: 07/15/2018 08:17 AM »
I don't understand this fascination with designing in zero-G components into micro-gravity structures. The Bigelow B330 is designed for zero-G only, and inflatables are not a good idea when you need to take structural loads.

The core of a Bigelow expandable is rigid, and that is where most loads will go through. The skin will just hang on, which may be structurally acceptable, after all it is supposed to be quite tough.

But I agree that using a B330 is not ideal. If we assume the station will be constructed by BFS, then its payload bay has a volume of 825 m3, a lot more than interior of an expanded B330. There must be a better way to utilize that space. Note that BA 2100 at 17.8m length is too big to fit. I would really like to use a module sized exactly to fit into non-cylindrical BFS payload bay, either rigid or expandable, something like this:

https://forum.nasaspaceflight.com/index.php?topic=44127.msg1748690#msg1748690

Sadly I dont see any such model in Sketchup warehouse..

Another consideration is that if you want to dock with a spinning station, you need to match spin first. Thus docking port must be located exactly at spin axis not just for the station, but also dockee craft. Could be done with a Dragon, but BFS docking port is supposedly on top and I doubt it will work..
« Last Edit: 07/15/2018 08:33 AM by blasphemer »

Offline Paul451

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Re: Realistic, near-term, rotating Space Station
« Reply #934 on: 07/15/2018 12:19 PM »
I think even Bigelow Aerospace has stopped using the term inflatable, in favour of expandable, to get away from the notion of a balloon which can pop.

I thought they've always avoided using "inflatable". But the pedant in me gets annoyed at their choice. Balloons also "expand". And non-stretching tyres are "inflated". They're making a distinction that doesn't exist in the actual words.

The main advantage of solid modules is that the on-orbit setup period is much reduced, because you already installed everything into the module while it was on the ground - including some facilities which might be impossible/very difficult to install in an expandable once on-orbit.

Bigelow's design has a truss core and two rigid end-caps where most equipment goes, and at least some can presumably do so before launch. (Depending on how much it needs to telescope when packed for launch. A 13m BA-330 in a 11m fairing, for example, should be able to carry a lot.)

Offline Paul451

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Re: Realistic, near-term, rotating Space Station
« Reply #935 on: 07/15/2018 01:50 PM »
Most people use BA-330's and BA-2100 because the numbers exist. Deployed length and width, and launch mass. Even price, for the BA-330. Makes it easier to use in a what-if compared to proposing a custom hab.

They are designed for zero-G uses, so they are ill-suited for artificial gravity applications.

You keep saying it, but you've said nothing that demonstrates it. They can handle loads of 10 tonnes per square metre. Bet your roof and floor can't, and yet your home manages to stand up under a whole 1g.

The BA2100 is only a concept

All Bigelow modules except Genesis & Beam are concepts. None of them exist except as mock-ups at Bigelow HQ. And both BA-330 and BA-2100 have been built in mock-up.

They presumably don't advertise BA-2100 because they can't actually deliver it to orbit yet. It exceeds even FH's capacity.

But, when speaking of Bigelow's concepts, its also worth noting that they've proposed their modules for Lunar bases, ie, under (some) gravity. So they're open to fitting modules to purpose.

Plus, with the availability of upcoming large-diameter launchers like the New Glenn and BFS, the need for expandables is reduced.

There's a mass-efficiency issue. Hab modules are mostly empty space. A module that would fill the BFS's payload area would probably not mass 150 tonnes. So if you shrink the empty space, you can use that spare mass to ship ancillary systems. Solar panels, radiators, etc, etc.

So let's focus on the requirements - how much space is needed to prove out at micro-gravity station?

Micro?

If you meant spin, the it depends on what you are trying to prove. The basics only require animal studies. In theory a stand-alone Dragon-Lab module rotating around its "vertical" axis. ECLSS and power from the Trunk. Or if the capsule can work upside down (easy to test on Earth), you could spin it end-over-end (baton) with its own upper-stage as a counterweight, lengthening the structure, allowing higher g-loads at a given spin-rate.

Next level is a longer duration, human-tended animal study. Simplest (assuming we aren't expecting astros to live in a Dragon for six months) would be a BA-330 (haha!) on a docking node, launched on an FH with a lengthened fairing, with the node on-orbit remaining mated to the upper-stage that launched them. This length allows Mars g at moderate spin-rates (<5RPM) (plus lunar g part way up) and Earth g at high spin-rates (>7RPM).

The spin-plane sides of the node would have radiators and solar panels. The axial sides would be docking adaptors. Then you launch a Dragon-crew with two astros and the animals. And a cargo Dragon with everything that couldn't be fitted internally before launch. (The non-inflatable node would carry some in it's empty space.)

(If the length doesn't work, you would require separate launches for node and hab. Which means an awkward self-docking of modules. A system which doesn't strictly exist yet, but really should, IMO.)

The two capsules would dock before spin-up, and remain attached at the axis during spin. You have to have the crew capsule, as a life-boat, so keeping the cargo module balances the structure, reducing the amount of dead-mass needed to stabilise the spin. Being on the rational axis, it should be safe to evac the station in an emergency without de-spinning, but normal procedure would be to de-spin before changing cargo/crew.

Next level, add another hab module instead of the upper-stage. (Now we really require self-docking.) Let's you fly more crew and lets the crew quarters be separate from the stinky animal lab.

If humans turn out not to be able to handle >5RPM for long period, but you want to test high g-loads, you need to add more structure between the habs and the docking node. These don't have to be very long though, 30-40m each arm, unless you are trying to reach 1g at 2RPM or something ridiculous. (IMO, if humans require a full 1g at very low RPMs, we might as well end the manned space program until someone invents some magitech that fundamentally changes the rules.)

Anything bigger is overkill for a station merely intended to "prove" the concept.

Offline blasphemer

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Re: Realistic, near-term, rotating Space Station
« Reply #936 on: 07/15/2018 06:31 PM »
(IMO, if humans require a full 1g at very low RPMs, we might as well end the manned space program until someone invents some magitech that fundamentally changes the rules.)

Sure, but why mention RPM here? We are quite screwed if humans require full 1g, period. In that case only orbital colonies will be realistic, not surface ones, and space colonization will be quite a bit harder. But then you may as well throw more trusses and modules on the station to achieve any RPM you like. Any viable colony is going to be inevitably quite large anyway. A near term, small test station with professional astronauts staying on it for a year is one thing. But you aint gonna have colonists living their lives at 5 RPM no matter what the human tolerance to RPM is.
« Last Edit: 07/15/2018 06:41 PM by blasphemer »

Offline dror

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Re: Realistic, near-term, rotating Space Station
« Reply #937 on: 07/15/2018 07:28 PM »

But I agree that using a B330 is not ideal. If we assume the station will be constructed by BFS, then its payload bay has a volume of 825 m3, a lot more than interior of an expanded B330. There must be a better way to utilize that space. Note that BA 2100 at 17.8m length is too big to fit. I would really like to use a module sized exactly to fit into non-cylindrical BFS payload bay, either rigid or expandable, something like this:

https://forum.nasaspaceflight.com/index.php?topic=44127.msg1748690#msg1748690

Sadly I dont see any such model in Sketchup warehouse..

I'm sure that if you PM Lamontagne he will happily hand it over

Also,
Please consider fairing-incorporated structures as an alternative.
Cheack out :
http://selenianboondocks.com/2014/10/integral-payload-fairing-habitats/
"If we crave some cosmic purpose, then let us find ourselves a worthy goal. "
Carl Sagan, Pale Blue Dot

Offline Coastal Ron

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Re: Realistic, near-term, rotating Space Station
« Reply #938 on: 07/15/2018 08:24 PM »
Most people use BA-330's and BA-2100 because the numbers exist. Deployed length and width, and launch mass. Even price, for the BA-330. Makes it easier to use in a what-if compared to proposing a custom hab.

Just because dimensions and pricing exist does not mean that they can be used for applications they are not designed for.

Quote
They are designed for zero-G uses, so they are ill-suited for artificial gravity applications.

You keep saying it, but you've said nothing that demonstrates it.

If I were to say that the Empire State building would make a great rocket because it already looks like a rocket, why would I then demand that YOU disprove the idea?

Bigelow modules are designed for zero-G applications, so using them in artificial gravity applications should only be done after an engineering analysis shows that they can, in fact, handle the anticipated loads. For instance, the central truss is likely using to keep the ends of the module from expanding out, so they have a design load specifically for that. Adding more load means they would have to be redesigned - is that possible?

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They can handle loads of 10 tonnes per square metre. Bet your roof and floor can't, and yet your home manages to stand up under a whole 1g.

You're making my point for me - my house is designed for specific loads, as are Bigelow modules. Using them in unintended ways doesn't mean you end up with a safer structure.

Quote
The BA2100 is only a concept
...
But, when speaking of Bigelow's concepts, its also worth noting that they've proposed their modules for Lunar bases, ie, under (some) gravity. So they're open to fitting modules to purpose.

No one knows what is needed for zero-G space stations, so Robert Bigelow decided to spend his own money to propose possible future solutions to unknown needs. But if someone had a firm need for something that is not a B330 or BA2100, Bigelow would not hesitate to build exactly what a customer wanted.

Which is why I have been suggesting that it's better to start with requirements before making decisions on using what's available.

Quote
Plus, with the availability of upcoming large-diameter launchers like the New Glenn and BFS, the need for expandables is reduced.

There's a mass-efficiency issue. Hab modules are mostly empty space. A module that would fill the BFS's payload area would probably not mass 150 tonnes. So if you shrink the empty space, you can use that spare mass to ship ancillary systems. Solar panels, radiators, etc, etc.

There is no "mass-efficiency issue". You're paying for the launch on a reusable rocket, not for the mass. And if you want to maximize the space inside of the rigid modules you can pack them with equipment and supplies.

Quote
So let's focus on the requirements - how much space is needed to prove out at micro-gravity station?

Micro?

If you meant spin, the it depends on what you are trying to prove. The basics only require animal studies. In theory a stand-alone Dragon-Lab module rotating around its "vertical" axis.

What humans need to know can only be found out by experimenting on humans. And since setting up colonies on our Moon and on Mars is of HUGE interest, then what we should focus on first is artificial gravity space stations that can provide a minimum of 1/3 G, with the option of operating at 1/6 G too. They also need to be sized in order for humans to actually live and work on them for periods of at least a year, or however long it takes to do studies to see if micro-gravity environments mitigate some or all of the effects of zero-G.

Because the goal has to be that we need to find out as soon as possible how humanity will be able to expand out into space while not only surviving, but thriving. Otherwise, why else should we spend money on sending humans to space?
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline Star-Drive

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Re: Realistic, near-term, rotating Space Station
« Reply #939 on: 07/15/2018 09:29 PM »

What humans need to know can only be found out by experimenting on humans. And since setting up colonies on our Moon and on Mars is of HUGE interest, then what we should focus on first is artificial gravity space stations that can provide a minimum of 1/3 G, with the option of operating at 1/6 G too. They also need to be sized in order for humans to actually live and work on them for periods of at least a year, or however long it takes to do studies to see if micro-gravity environments mitigate some or all of the effects of zero-G.

Because the goal has to be that we need to find out as soon as possible how humanity will be able to expand out into space while not only surviving, but thriving. Otherwise, why else should we spend money on sending humans to space?

All:  Gary Hudson over at the Space Studies Institute (SSI) has been beating the drum for the need of artificial-gee for human spaceflight for years now and I totally agree with Gary that before we establish long term colonies on the Earth's Moon and Mars, we had first find out if humans can breed in and live long-term under 1/6 and 1/3 gee gravity fields.  A good summary of Hudson's approach to finding the answer to these questions is at the below December 2015 YouTube video URL.  In this video Gary lays out a moderately low cost approach to finding the answers to these biological compatibility questions.

https://www.youtube.com/watch?time_continue=10&v=xO1Pvtv_A4k

Best, Paul M.
Star-Drive

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