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HEFT2 Deep Space Habitat (DSH) Presentation
by
yg1968
on 26 Mar, 2011 23:31
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#1
by
Chris Bergin
on 27 Mar, 2011 00:20
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Some very nice digging going on here YG
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#2
by
sdsds
on 27 Mar, 2011 00:51
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Some very nice digging going on here YG
Yes, and greatly appreciated. Thanks!
Noting from page 3, "DSH Element Description": Crewed Mission Duration: 365 days. They really seem to be taking the NEO mission to heart, which of course is reasonable since the President featured that in his proposals.
The sense that I get from Congress is that even that kind of mission will need to be approached in a phased implementation, i.e. maybe the DSH crewed mission duration should be "evolvable" to 365 days.
If 365 days were the unicorn, perhaps 36.5 days could be the pony?
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#3
by
Patchouli
on 27 Mar, 2011 02:17
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Why not use an expandable transhab type structure instead?
A BA-330 type module would offer more habitable volume,better radiation shielding and would weigh less.
The main reason for the larger volume other then psychological it offers the option of a short arm centrifuge.
The ISS style module leaves the Nautilus X style centrifuge as your only option.
I'd also not fly the urine recycler as a mission critical item it has been more trouble then it's worth on ISS.
Maybe fully isolate it from the potable water loop and have it supply a backup O2 generator.
You get the option of being able to recycle every last bit of water but you don't put as many systems or the crew at risk of contamination.
Plus the hydrogen could be use in thrusters for station keeping.
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#4
by
pathfinder_01
on 27 Mar, 2011 04:04
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I agree with most of what it said so far. There is a big partner in Bigleow that they could use to create something lightweight.
However I think I would fly the Urine recycler. It is just one of those things that when it breaks down no one wants to repair (i.e. Like a sewer system) but it does work from what I have read. The real issue with the ISS life support systems is that they take more labor than thought and are less reliable than planned.
Also 365 days for a crew of 3 might not be that ambitious. Skylab could support 3 crews of 3 people for 3 months each so in theory it could support 3 people for 270 days with no recycling. ISS recycling can reduce water demand for the crew byu p to 65% so 365 for 3 people might not be that extreme esp. as in theory the ISS has closed the oxygen loop.
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#5
by
Patchouli
on 27 Mar, 2011 04:29
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I agree with most of what it said so far. There is a big partner in Bigleow that they could use to create something lightweight.
However I think I would fly the Urine recycler. It is just one of those things that when it breaks down no one wants to repair (i.e. Like a sewer system) but it does work from what I have read. The real issue with the ISS life support systems is that they take more labor than thought and are less reliable than planned.
Also 365 days for a crew of 3 might not be that ambitious. Skylab could support 3 crews of 3 people for 3 months each so in theory it could support 3 people for 270 days with no recycling. ISS recycling can reduce water demand for the crew byu p to 65% so 365 for 3 people might not be that extreme esp. as in theory the ISS has closed the oxygen loop.
I'd still fly the urine recycler the only difference is I'd just have it isolated from the potable water supply.
Seems if a membrane fails you could end up having to dump all the water and cleaning and or replacing everything contaminated.
Bad enough to do in LEO but you'd really have a problem BEO.
They actually had to do such a plumbing repair on Salyut 7 but because it froze and several lines broke.
Though I think on ISS they can decide to put it in the potable water or use it as utility water based on test results.
One good use for the recovered water might be what's called an electrothermo thruster which could be useful it's power requirements are fairly low yet has an ISP of 800.
http://www.hobbyspace.com/nucleus/index.php?itemid=27360I think Bigelow actually has this planned for Sundancer it has two OMS systems one a conventional system and the other fueled by waste gases and fluids likely an electrothermo thruster or plasma arcjet.
One really good location for DSH might be GEO it's close but still in a deep space environment.
They also could attempt satellite servicing.
Yes I know it's not cost effective to repair GEO sats but in this case you already paid to have the crew up there so adding the mission would be a minor increase and would teach techniques and methods needed for doing repairs in deep space.
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#6
by
madscientist197
on 27 Mar, 2011 12:46
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The last side basically says that NASA has serious directional, structural and budget problems that need to be fixed first. No surprises there -- probably no mitigatory actions in the works, either.
It might be nice, though, if they were a little more direct in their recommendations as (for example) "NASA-wide transformational change is required to significantly improve affordability and meet budget constraints" is a rather non-specific recommendation.
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#7
by
Robotbeat
on 27 Mar, 2011 20:17
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Hmmm... this fits pretty closely part of what I'd want to do if I were "emperor of NASA." DSH is a bit bigger than Salyut, which held 3 crew for over 200 days, so this is about right (when you add in the volume of Orion, etc). I like it. About the same size as Destiny (and a little smaller than node 4 size). I do wonder if it could be slightly expanded to 4 crew, perhaps if they added a little extra space (a lander? an airlock?) in addition to the DSH and Orion. That would be nice to have for a Mars mission.
Just think, it's totally doable to fly something like this! We've been doing this for over a decade in LEO on ISS, which is made out of many modules which are around the same size as DSH. The relatively low mass of DSH also makes the mission cost a lot less, because it means your propulsion requirements are a LOT lower for a given delta-v, which is a really good thing even with SLS. And DSH doesn't necessarily need SLS, either, so can be launched on an EELV-class launch vehicle if need be. Good to have options and flexibility!
I like this A LOT.
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#8
by
Robotbeat
on 27 Mar, 2011 20:35
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This is rather low-risk and an eminently doable element. I really, really like it, the more I read about it. THIS IS EXACTLY WHAT WE SHOULD BE FUNDING!!!
(and a lander
)
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#9
by
robertross
on 28 Mar, 2011 00:57
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Here is a recent HEFT2 presentation on Deep Space Habitats:
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20110006982_2011003312.pdf
(Reposting here, as I had the following in the wrong thread):
Good find!
I like how they are showcasing the ISS ECLSS for use on this.
(personal note: I hope those few detractors can see WHERE the benefit of ISS component development is crucial for deep space missions)
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#10
by
Robotbeat
on 28 Mar, 2011 01:56
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Here is a recent HEFT2 presentation on Deep Space Habitats:
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20110006982_2011003312.pdf
(Reposting here, as I had the following in the wrong thread):
Good find!
I like how they are showcasing the ISS ECLSS for use on this.
(personal note: I hope those few detractors can see WHERE the benefit of ISS component development is crucial for deep space missions)
Agreed, especially with the last part. A while ago, I might have considered myself an ISS detractor, but I've long since realized that what is used for ISS has very direct application to deep space applications and is just about the perfect low-risk test bed for such technologies and components.
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#11
by
robertross
on 28 Mar, 2011 02:08
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yay, a convert! Welcome aboard!
LOL
We all have our own likes & aspirations for spaceflight. My problem is I want all the groups to have a slice of it, and hopefully we can meet at some point where everyone has gained.
There are some aspects to ISS systems which might have a tough time in deep space habitats: specifically if we want an artificial gravity system provided. ISS systems are designed for microgravity, so they aren't necessarily a 1:1 transfer. I realize that. However, there would also be times when AG can fail, or ops require no AG, or the journey is too short to require it. In those cases, having that built-in capability can be essential, so these 'baby steps' we are taking at developing these capabiltities now can become contigency factors later on.
So for a lower-cost capability, we use such a habitat as a non-AG version, and perhaps fly one in LEO WITH that AG capability to test those system long term.
One thing I'm not sure about is if the ISS systems are hardened against radiation. I know the station laptop computers aren't, but not sure about ECLSS. I wouldn't mind clarification from one our esteemed members
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#12
by
scienceguy
on 28 Mar, 2011 02:13
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It's interesting what they said about solar electric propulsion. I agree that they should research that more.
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#13
by
pathfinder_01
on 28 Mar, 2011 03:20
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yay, a convert! Welcome aboard! LOL
We all have our own likes & aspirations for spaceflight. My problem is I want all the groups to have a slice of it, and hopefully we can meet at some point where everyone has gained.
There are some aspects to ISS systems which might have a tough time in deep space habitats: specifically if we want an artificial gravity system provided. ISS systems are designed for microgravity, so they aren't necessarily a 1:1 transfer. I realize that. However, there would also be times when AG can fail, or ops require no AG, or the journey is too short to require it. In those cases, having that built-in capability can be essential, so these 'baby steps' we are taking at developing these capabiltities now can become contigency factors later on.
So for a lower-cost capability, we use such a habitat as a non-AG version, and perhaps fly one in LEO WITH that AG capability to test those system long term.
One thing I'm not sure about is if the ISS systems are hardened against radiation. I know the station laptop computers aren't, but not sure about ECLSS. I wouldn't mind clarification from one our esteemed members
So far HEFt has no plans for artificial gravity.
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#14
by
Robotbeat
on 28 Mar, 2011 03:31
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yay, a convert! Welcome aboard! LOL
We all have our own likes & aspirations for spaceflight. My problem is I want all the groups to have a slice of it, and hopefully we can meet at some point where everyone has gained.
There are some aspects to ISS systems which might have a tough time in deep space habitats: specifically if we want an artificial gravity system provided. ISS systems are designed for microgravity, so they aren't necessarily a 1:1 transfer. I realize that. However, there would also be times when AG can fail, or ops require no AG, or the journey is too short to require it. In those cases, having that built-in capability can be essential, so these 'baby steps' we are taking at developing these capabiltities now can become contigency factors later on.
So for a lower-cost capability, we use such a habitat as a non-AG version, and perhaps fly one in LEO WITH that AG capability to test those system long term.
One thing I'm not sure about is if the ISS systems are hardened against radiation. I know the station laptop computers aren't, but not sure about ECLSS. I wouldn't mind clarification from one our esteemed members
So far HEFt has no plans for artificial gravity.
And that's fine by me, FWIW. I don't think it's absolutely necessary, even for a Mars mission. ISS should be investigating this, even more than they already are.
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#15
by
Patchouli
on 28 Mar, 2011 23:28
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I don't think anything needs to be invented for DSH just buy an off the shelf station and adapt it.
The Bigelow Sundancer pretty much already is a self contained station.
I can't think of anything better suited for the mission and it's perfectly sized large enough that it's not cramped but not so large it would need an HLV to be taken to a BEO location.
It also should be possible to perform this mission using just EELV class LVs.
A Delta IV-H or F9-H should be able to place a SunDancer in GEO or L1.
Or if you want to be creative attach a SEP tug to it and once it's in the desired orbit use the extra solar power to power experiments such as a mag shield or advanced closed loop life support.
Then an Orion plus Centaur could visit it.
Replacement of consumables as well as trash disposal could be handled by small SEP ferries and COTS vehicles.
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#16
by
robertross
on 28 Mar, 2011 23:40
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I don't think anything needs to be invented for DSH just buy an off the shelf station and adapt it.
The Bigelow Sundancer pretty much already is a self contained station.
It also should be possible to perform this mission using just EELV class LVs.
Ask yourself: what is the purpose of Sundancer?
LEO
These were not designed for deep space, and it would likely cost more to adapt them, rather than design from the ground up for deep space.
Edited: 'removed shell comment' & added 'likely'
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#17
by
Patchouli
on 28 Mar, 2011 23:49
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I don't think anything needs to be invented for DSH just buy an off the shelf station and adapt it.
The Bigelow Sundancer pretty much already is a self contained station.
It also should be possible to perform this mission using just EELV class LVs.
Ask yourself: what is the purpose of Sundancer?
LEO
These were not designed for deep space, and it would cost more to adapt them, rather than design from the ground up for deep space. Besides, most of it is just a shell.
LEO space hotel but it does outperform a can type module in every way that counts for this.
It would no more work then any other LEO station and a lot less then something ground up.
A Russian DOS module for example would require the same amount of work but would be heavier and much less capable and an ISS module far more work as it lacks all the systems to operate as an independent station.
Besides Bigelow already is considering BEO uses for their station modules.
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#18
by
Jason1701
on 28 Mar, 2011 23:50
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I don't think anything needs to be invented for DSH just buy an off the shelf station and adapt it.
The Bigelow Sundancer pretty much already is a self contained station.
It also should be possible to perform this mission using just EELV class LVs.
Ask yourself: what is the purpose of Sundancer?
LEO
These were not designed for deep space, and it would cost more to adapt them, rather than design from the ground up for deep space. Besides, most of it is just a shell.
How do you know any of this?
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#19
by
Robotbeat
on 28 Mar, 2011 23:51
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I don't think anything needs to be invented for DSH just buy an off the shelf station and adapt it.
The Bigelow Sundancer pretty much already is a self contained station.
It also should be possible to perform this mission using just EELV class LVs.
Ask yourself: what is the purpose of Sundancer?
LEO
These were not designed for deep space, and it would cost more to adapt them, rather than design from the ground up for deep space. Besides, most of it is just a shell.
LEO space hotel but it does outperform a can type module in every way that counts for this....
Are you sure about that? The DSH would need to function as a node, which could cause clearance issues for an inflatable. Salyut wasn't that big, but was fine for 3 crew for hundreds of days at a time, and this will have considerably more volume.
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#20
by
Patchouli
on 29 Mar, 2011 00:01
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I don't think anything needs to be invented for DSH just buy an off the shelf station and adapt it.
The Bigelow Sundancer pretty much already is a self contained station.
It also should be possible to perform this mission using just EELV class LVs.
Ask yourself: what is the purpose of Sundancer?
LEO
These were not designed for deep space, and it would cost more to adapt them, rather than design from the ground up for deep space. Besides, most of it is just a shell.
LEO space hotel but it does outperform a can type module in every way that counts for this....
Are you sure about that? The DSH would need to function as a node, which could cause clearance issues for an inflatable. Salyut wasn't that big, but was fine for 3 crew for hundreds of days at a time, and this will have considerably more volume.
They had some psychological issues.
If you can give them extra space and stay in the mass budget do it in this case it's actually less mass.
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#21
by
robertross
on 29 Mar, 2011 00:13
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I don't think anything needs to be invented for DSH just buy an off the shelf station and adapt it.
The Bigelow Sundancer pretty much already is a self contained station.
It also should be possible to perform this mission using just EELV class LVs.
Ask yourself: what is the purpose of Sundancer?
LEO
These were not designed for deep space, and it would cost more to adapt them, rather than design from the ground up for deep space. Besides, most of it is just a shell.
How do you know any of this?
Umm, their own data?
"Bigelow Aerospace’s planned first full-scale module is
the Sundancer, targeted for launch and orbit in 2014."
Orbit. (of Earth, implied)
edit to add: and this: "Radiation Protection:
•Bigelow Aerospace’s shielding is equivalent to or better than the International Space Station and substantially reduces the dangerous impact of secondary radiation."
Not anywhere near good enough for hard radiation, which would be seen outside of Earth's magnetic field. If they put something up there for Sundancer that says they are modifying, or planning to modify it for BEO, let me know.
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#22
by
Jason1701
on 29 Mar, 2011 00:16
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I don't think anything needs to be invented for DSH just buy an off the shelf station and adapt it.
The Bigelow Sundancer pretty much already is a self contained station.
It also should be possible to perform this mission using just EELV class LVs.
Ask yourself: what is the purpose of Sundancer?
LEO
These were not designed for deep space, and it would cost more to adapt them, rather than design from the ground up for deep space. Besides, most of it is just a shell.
How do you know any of this?
Umm, their own data?
"Bigelow Aerospace’s planned first full-scale module is
the Sundancer, targeted for launch and orbit in 2014."
Orbit. (of Earth, implied)
No public sources say that Bigelow's modules are "shells." Your statement that it would cost less to completely redesign them than to adapt them for BEO is baseless without detailed engineering and accounting data, which I don't see how you could have if you aren't an employee.
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#23
by
manboy
on 29 Mar, 2011 00:17
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Does anyone have a link to the HEFT Element Catalog?
Why not use an expandable transhab type structure instead?
A BA-330 type module would offer more habitable volume,better radiation shielding and would weigh less.
I was thinking the same thing. Especially with Lori Garver's recent vist with Bob Bigelow.
I don't think anything needs to be invented for DSH just buy an off the shelf station and adapt it.
The Bigelow Sundancer pretty much already is a self contained station.
It also should be possible to perform this mission using just EELV class LVs.
Besides, most of it is just a shell.
No.
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#24
by
robertross
on 29 Mar, 2011 00:44
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No public sources say that Bigelow's modules are "shells." Your statement that it would cost less to completely redesign them than to adapt them for BEO is baseless without detailed engineering and accounting data, which I don't see how you could have if you aren't an employee.
modified my original post to ensure me beliefs for a BEO Sundancer weren't interpreted the wrong way.
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#25
by
JohnFornaro
on 29 Mar, 2011 14:24
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If 365 days were the unicorn, perhaps 36.5 days could be the pony?
Imagine a lunar mission for 36.5 days. Quite the pony, I'd say.
The last slide basically says that NASA has serious directional, structural and budget problems that need to be fixed first.
I'd agree with you completely.
This is rather low-risk and an eminently doable element. I really, really like it, the more I read about it. THIS IS EXACTLY WHAT WE SHOULD BE FUNDING!!!
Totally disagree, which is not the same thing as saying that Mars should not be considered as a destination.
What this report says is that we should go from orbiting the Earth at ISS and go directly to Mars via a 365 day mission. I'm not ok with this premise. This is a large step in capability, and I submit that it is a capability based virtually entirely on fantasy, as regards our likely abilities and likely budgets.
This project is wasting the efforts of a great number of talented people who should be working on lesser goals with more of a chance of actually being accomplished in the next decade or so.
Is there a pyramid on Mars or something? Why are our efforts being directed here with such compulsion? This is not the next thing we should be doing.
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#26
by
yg1968
on 29 Mar, 2011 14:48
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What this report says is that we should go from orbiting the Earth at ISS and go directly to Mars via a 365 day mission. I'm not ok with this premise. This is a large step in capability, and I submit that it is a capability based virtually entirely on fantasy, as regards our likely abilities and likely budgets.
This project is wasting the efforts of a great number of talented people who should be working on lesser goals with more of a chance of actually being accomplished in the next decade or so.
Is there a pyramid on Mars or something? Why are our efforts being directed here with such compulsion? This is not the next thing we should be doing.
I don't think that it says that we should go to Mars directly. If you look at slide 16, there is a lot of destinations in between LEO and Mars.
It also doesn't say that the DSH should be the first thing that should be built. If you look at if you look at slide 20 of this other recent presentation (which is a similar slide but with a lot more details), the CPS is the first thing that needs to be developed for any kind of BLEO mission but the DSH comes much later and possibly even after a moon lander:
http://www.nasa.gov/pdf/518779main_11_02_Exploration.pdf
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#27
by
Patchouli
on 29 Mar, 2011 17:20
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What this report says is that we should go from orbiting the Earth at ISS and go directly to Mars via a 365 day mission. I'm not ok with this premise. This is a large step in capability, and I submit that it is a capability based virtually entirely on fantasy, as regards our likely abilities and likely budgets.
This project is wasting the efforts of a great number of talented people who should be working on lesser goals with more of a chance of actually being accomplished in the next decade or so.
Is there a pyramid on Mars or something? Why are our efforts being directed here with such compulsion? This is not the next thing we should be doing.
I don't think that it says that we should go to Mars directly. If you look at slide 16, there is a lot of destinations in between LEO and Mars.
It also doesn't say that the DSH should be the first thing that should be built. If you look at if you look at slide 20 of this other recent presentation (which is a similar slide but with a lot more details), the CPS is the first thing that needs to be developed for any kind of BLEO mission but the DSH comes much later and possibly even after a moon lander:
http://www.nasa.gov/pdf/518779main_11_02_Exploration.pdf
Whatever route for the baseline DSH is taken it would be one of the easier projects and certainly would be easier then the lunar lander.
The unflown habitation module, a node, and the propulsion from a large comsat could be used as DSH.
http://en.wikipedia.org/wiki/Habitation_ModuleNot the most mass efficient solution but if you have already have an HLV it could be the cheapest.
The concept in the opening looks to be a combination of a a node and a destiny type module.
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#28
by
JohnFornaro
on 30 Mar, 2011 13:39
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First, since DSH is the "short pole" of the tent it should be worked on first. DSH is in a unique position since it is the "long pole" of the tent as well. It should be built first, landed on the Moon, along with, say half a dozen compatriots with various upgrades, and lived in for a year in that environment, where there is reduced gravity and distance from Earth.
Here we go again, with the dictionary definition of "distance". But I digress.
Second, certainly it is seen that DSH is "easier", than some other things; Easy is a less flashy way of saying "cheaper". And cheaper is better, unless the agency in question is also postulating the "unlimited budget scenario", which this HEFT2 presentation explicitly promises, I'd say.
We should not be "practicing" on DSH on its maiden flight to Mars; we should practice with it at least a year before, on the proximate destination. Which of course, should be the next destination, and that directly.
I have no idea what Mr. Bolden has been instructed to say upon the idea of going to Mars "DIRECT-ly". Could be a code word. I'm still going on his frenzied debate with that Congressman about how Mars was the "next destination", modified to be the "next ultimate destination", which kinda sez: That's also the last "destination". They went on and on about the meaning of the word "destination" and the word "next". Which sounded like "directly" to me, but hey. It was not a bright moment in the legislative and executive branch performances of late.
BTW, "next" has a contextual, meaningful relationship to "directly". Doesn't it?
This is going to sound a bit weird, but: It cannot be argued by policymakers that "directly" also means "indirectly", or "by any means which we eventually employ, considering that cost is no object". (Even if it doesn't mean "next"?)
These guys are all playing too many semantic games, none of it with an eye towards elucidating and explaining and justifying their choices to the ever patient taxpayer.
Just sayin'.
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#29
by
JosephB
on 30 Mar, 2011 18:30
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What this report says is that we should go from orbiting the Earth at ISS and go directly to Mars via a 365 day mission. I'm not ok with this premise. This is a large step in capability, and I submit that it is a capability based virtually entirely on fantasy, as regards our likely abilities and likely budgets.
This project is wasting the efforts of a great number of talented people who should be working on lesser goals with more of a chance of actually being accomplished in the next decade or so.
Is there a pyramid on Mars or something? Why are our efforts being directed here with such compulsion? This is not the next thing we should be doing.
I don't think that it says that we should go to Mars directly. If you look at slide 16, there is a lot of destinations in between LEO and Mars.
It also doesn't say that the DSH should be the first thing that should be built. If you look at if you look at slide 20 of this other recent presentation (which is a similar slide but with a lot more details), the CPS is the first thing that needs to be developed for any kind of BLEO mission but the DSH comes much later and possibly even after a moon lander:
http://www.nasa.gov/pdf/518779main_11_02_Exploration.pdf
Regarding that MPCV from page 5 (on the right):
Has anyone seen schematics, detailed images or good reading on this?
All I've ever come across is tiny thumbnails. Thanks!
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#30
by
I14R10
on 03 Apr, 2011 09:56
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#31
by
robertross
on 03 Apr, 2011 14:25
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#32
by
yg1968
on 11 Jun, 2011 03:20
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#33
by
Robotbeat
on 11 Jun, 2011 04:28
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#34
by
Patchouli
on 11 Jun, 2011 04:48
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I wonder if this could eventually evolve into a module for Nautilus-X.
Add a high performance propulsion module and centrifuge you would have an early version of Nautilus-X.
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#35
by
Robotbeat
on 11 Jun, 2011 04:54
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I wonder if this could eventually evolve into a module for Nautilus-X.
Add a high performance propulsion module and centrifuge you would have an early version of Nautilus-X.
Yeah, I think a smaller module like this makes more sense than the Nautilus-X idea of a big, heavy central node. A smaller module allows more flexibility with a modular approach, since you can just add modules to fit the mission requirements, but have an initial module which is quite small and thus suitable for missions which are beyond the capability of Orion but still small enough to actually be accomplished on a reasonable budget.
And I like the idea of water wall shielding for the crew quarters... I had another idea of an even more mass-efficient way to do shielding.
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#36
by
Lampyridae
on 20 Jun, 2011 14:04
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I wonder if this could eventually evolve into a module for Nautilus-X.
Add a high performance propulsion module and centrifuge you would have an early version of Nautilus-X.
Yeah, I think a smaller module like this makes more sense than the Nautilus-X idea of a big, heavy central node. A smaller module allows more flexibility with a modular approach, since you can just add modules to fit the mission requirements, but have an initial module which is quite small and thus suitable for missions which are beyond the capability of Orion but still small enough to actually be accomplished on a reasonable budget.
And I like the idea of water wall shielding for the crew quarters... I had another idea of an even more mass-efficient way to do shielding.
You can also pump the water into a "storm shelter" radiation bag, getting 3 or 4x the relative thickness of shielding.
Agreed that small modules are the way to go. Build them earlier, fly them earlier. If you need more volume, stack them together.
)
LOL