Small commonality habitat module.http://spirit.as.utexas.edu/~fiso/telecon/Griffin_7-29-15/This is for rovers, landers, space exploration vehicles and logistics supply modules. The DSH is likely to use a large diameter module.Diameter is not set in stone yet but the preference is for approx 3m which just so happens to be in Cygnus size range. This standardizing on common module size has lot of benefits. One example I can think of is Masten Xeus lunar lander, the same lander with very little modifications could be used to deliver a supply module. A rover with 2 crew for 2 week exploration mission. A taxi module for ferrying 4 or more crew to and from a lunar base. Habitat modules for small lunar outpost.
Deep Resonant Orbit (DRO)
Quote from: TrevorMonty on 11/01/2015 12:59 pmDeep Resonant Orbit (DRO)Doesn't DRO usually refer to a distant retrograde orbit? What's a "deep resonant orbit"?
Can't it be both?Anyway, I listened in to the (public) teleconference today. NASA hasn't made a decision on whether to do a big monolithic habitat or a bunch of modular ones. But they have talked about a small volume habitat that can serve multiple roles, such as a pressurized rover, ascent vehicle volume, etc.
Quote from: Robotbeat on 11/05/2015 03:29 amCan't it be both?Anyway, I listened in to the (public) teleconference today. NASA hasn't made a decision on whether to do a big monolithic habitat or a bunch of modular ones. But they have talked about a small volume habitat that can serve multiple roles, such as a pressurized rover, ascent vehicle volume, etc.Standardizing on a common small volume habitat shared between different roles is a good way to keep costs down.
Quote from: RonM on 11/05/2015 05:03 amQuote from: Robotbeat on 11/05/2015 03:29 amCan't it be both?Anyway, I listened in to the (public) teleconference today. NASA hasn't made a decision on whether to do a big monolithic habitat or a bunch of modular ones. But they have talked about a small volume habitat that can serve multiple roles, such as a pressurized rover, ascent vehicle volume, etc.Standardizing on a common small volume habitat shared between different roles is a good way to keep costs down.Isn't it more a matter of standardizing the life support system? Considering the total ISS volume could be matched by a single-launch DSH/Skylab 2...well why not just put the same (modernized naturally) systems on board? The only difference is you'd put the same amount of equipment into a single module instead of several; from the POV of power there's no difference and thermally it's easier to handle one large module instead of several tiny ones.The only trouble I'd see with using a large module might be structural, depending on whether they incorporate the craft into the rocket or encase it all in a shroud.
...well why not just put the same (modernized naturally) systems on board? The only difference is you'd put the same amount of equipment into a single module instead of several; from the POV of power there's no difference and thermally it's easier to handle one large module instead of several tiny ones.
Quote from: redliox on 11/10/2015 08:30 pmThe only difference is you'd put the same amount of equipment into a single module instead of several;One downside is that you would lose redundancy. What if the single, large ECLSS broke down?
The only difference is you'd put the same amount of equipment into a single module instead of several;
Quote from: RonM on 11/05/2015 05:03 amStandardizing on a common small volume habitat shared between different roles is a good way to keep costs down.Isn't it more a matter of standardizing the life support
Standardizing on a common small volume habitat shared between different roles is a good way to keep costs down.
These are the reasons why designing a new habitable volume by starting with an existing design and making only minimal tweaks would be attractive.
Thus the Lockheed Martin proposal for its "kissing Orions" (Plymouth Rock) mission.
Keeping the habitat separate from the transportation to the habitat means neither has to be compromised.
Quote from: Coastal Ron on 11/10/2015 09:11 pmQuote from: redliox on 11/10/2015 08:30 pmThe only difference is you'd put the same amount of equipment into a single module instead of several;One downside is that you would lose redundancy. What if the single, large ECLSS broke down?Isn't Redilox suggesting each ECLSS unit would be the same size, you'd just have a bunch in a single large module, rather than one-each in smaller modules? So you'd still have precisely the same redundancy for anything short of a hull breach.
Once again, there's minimal difference whether you use four little modules or one large one (from a system requirement POV), but since we're no longer bound by the shuttle's tight fuselage there's no harm in going big so long as you stay within launch vehicle capability. Screw sardine cans...I want a full-body-tuna can!
A modular approach means they can deliver each module with SLS during a crew mission, as DSH grows so does mission length. Also there is no large outlay for one large single DSH which would require a dedicated SLS launch. The build cost of the modules gets spread over multiple years, if there are budget cuts NASA still has destination even if mission length maybe cut.Assembly maybe something like this. Module 1) EAM with open loop ECLSSModule 2) Closed loop ECLSSModule 3) Lab.
Assembly maybe something like this. Module 1) EAM with open loop ECLSSModule 2) Closed loop ECLSSModule 3) Lab.
Once again, there's minimal difference whether you use four little modules or one large one (from a system requirement POV), but since we're no longer bound by the shuttle's tight fuselage there's no harm in going big so long as you stay within launch vehicle capability.
Quote from: redliox on 11/11/2015 05:40 amOnce again, there's minimal difference whether you use four little modules or one large one (from a system requirement POV), but since we're no longer bound by the shuttle's tight fuselage there's no harm in going big so long as you stay within launch vehicle capability.Maybe that can be said from a functional standpoint, but it can't be said from an industrial base standpoint. 5m diameter modules can be built anywhere in the world and moved by ground or air - as well as be launched by a fleet of international launchers. Modules that are larger can only be moved by water over long distances, which limits the industrial base that can be utilized, and that affects the overall costs.And money has to be a primary consideration for whatever we do in space.
My impression was that the cutoff for routine road & rail transport was ~14ft, about 4.25m, with practical fully encumbered numbers being more like 3.5-3.8m. Falcon 9 is spoken of as the thing they built as large as possible which still fits on the freeway system.