A separate acronym section would help the reader that doesn't already know them and doesn't necessarily memorize them at first reading or is scanning the document.-ehb.
I was also planning to put in a submission dealing just with surface habitat construction. I had kind of gotten the impression that the contest was oriented towards surface systems and that they were not looking for a DRM which is what you have produced. But 'pioneering' is an awful vague term so who knows.
“This concept recognizes the value of a phased approach to building up a human presence on Mars. However, the reliance on SLS tanks as habitable volume would require significant changes to the design and operation of the SLS, and the technical challenges associated with those modifications were not recognized or considered. Thank you for participating.”
I respect their reasoning, but simultaneously I have to question it because professional engineers already have interest in using SLS tanks for deep space habitats, including for Martian vehicles; refer to these links on that note: http://forum.nasaspaceflight.com/index.php?topic=30609.0 http://forum.nasaspaceflight.com/index.php?topic=28481.msg878692#msg878692What does everyone here think?
Yea, I'm very skeptical of reusing wet propellant tanks. You have all kinds of difficulty in purging them, then they need to be outfitted with a huge mass of equipment which has no real means of being secured to the tank wall unless the tank has been heavily modified. And all of this work just saves you the mass of the pressure vessel which is a few tons, a small fraction of the total mass needed to make a decent habitat.The flaw is thinking that a space habitat's ratio of structural elements to furnishings is like a house on Earth. We use lots and lots of lumber and cement and nails and plaster to make the new house, then some beds and table and chairs are your furnishings, they are tiny in comparison to the mass of the house. Space Habitats are the reverse, the shell is minuscule and the furnishings are massive.
P.S. My submission for Expanded Polystyrene vaults covered with regolith was shot-down as well. “Similar constructed-then-buried structures have been suggested before. Insufficient assessment to determine if this proposal has a clear benefit. Thank you for participating.”I find this to be a bit unfair as I think I demonstrated a huge improvement in fabrication time and safety through the use of large low-density blocks. Perhaps they expected more comparisons with alternatives.
Bear in mind, the tanks themselves aren't 'reused'. I never was talking about using them ala the 1980s ideas of reusing shuttle fuel tanks to make mega-space stations. They would be used in the same way spare tanks from Saturn V were used to create Skylab; Skylab is cited as a working example of how pressure vessels from rocketry could be remodeled into habitats since it's literally been done before...and with 1970s technology.
Quote from: redliox on 09/18/2015 07:28 pmBear in mind, the tanks themselves aren't 'reused'. I never was talking about using them ala the 1980s ideas of reusing shuttle fuel tanks to make mega-space stations. They would be used in the same way spare tanks from Saturn V were used to create Skylab; Skylab is cited as a working example of how pressure vessels from rocketry could be remodeled into habitats since it's literally been done before...and with 1970s technology.The Skylab transformation was performed ON EARTH. It took an army of workmen. The furnishings had not been made brittle by freezing them to cryogenic temperatures. What they remodelled was an empty box with a few attachment points.
Quote from: A_M_Swallow on 09/18/2015 07:47 pmQuote from: redliox on 09/18/2015 07:28 pmBear in mind, the tanks themselves aren't 'reused'. I never was talking about using them ala the 1980s ideas of reusing shuttle fuel tanks to make mega-space stations. They would be used in the same way spare tanks from Saturn V were used to create Skylab; Skylab is cited as a working example of how pressure vessels from rocketry could be remodeled into habitats since it's literally been done before...and with 1970s technology.The Skylab transformation was performed ON EARTH. It took an army of workmen. The furnishings had not been made brittle by freezing them to cryogenic temperatures. What they remodelled was an empty box with a few attachment points.Exactly. I never said fuel tanks would be refitted in orbit or Mars.
I would say that they are unlikely to be as good in the ballistic and radiation protection as an expandable Bigelow style module, also maybe some chance for NASA to not have to foot the bill for such a Hab if private companies develop it.
The incredulous response from Innocentive made me think you were proposing something radical, but dry workshops aren't radical and would not require modifying the SLS that launches it, so their response makes no sense.
Quote from: Impaler on 09/19/2015 03:51 amI would say that they are unlikely to be as good in the ballistic and radiation protection as an expandable Bigelow style module, also maybe some chance for NASA to not have to foot the bill for such a Hab if private companies develop it.That I can agree with, although I haven't seen much Bigelow hardware flown in the last few years which casts a hint of doubt (sans the upcoming BEAM module for ISS). However, if NASA makes a decision to go inflatable in an announcement by the time SLS flies Bigelow would easily have a revival. I consider it a 50/50 choice, perhaps depending on whether the next batch of NASA management favors outsourcing to commercial or focusing on "in house" hardware (i.e. SLS tank modeling).Quote from: Impaler on 09/19/2015 03:51 amThe incredulous response from Innocentive made me think you were proposing something radical, but dry workshops aren't radical and would not require modifying the SLS that launches it, so their response makes no sense.Maybe they were looking for surface equipment more, or something 'more radical' yet somehow simple to build...as if anything in rocket science were truly simple!
