OFMM General Discussions Archive

[Pablo49]

Well if we got vessel stack to work, we could make a stack without having to use the Cook. To use the cook we have to assume we already have it built in orbit.

 

[Izack]

Looks like we're not using it anymore, but here's another view of the Cook concept, complete with Ravenstars, tanks, habs, cores, service modules and Ravenstars, ready to go.

 

[Ashaman42]

One problem I noticed with VesselStack is that even in the default scenario as shown in the photo is that if for some reason the two DGs acting as engines end up with different fuel levels is that you get a lot of twisting under thrust due to the CoG being off centre.

Though I guess that's more realistic so not necessarily a bad thing.

 

[Izack]

One problem I noticed with VesselStack is that even in the default scenario as shown in the photo is that if for some reason the two DGs acting as engines end up with different fuel levels is that you get a lot of twisting under thrust due to the CoG being off centre.

Though I guess that's more realistic so not necessarily a bad thing.

That could be averted by using a single engine, as we probably were going to do anyway:
[nomedia="http://www.orbithangar.com/searchid.php?ID=3865"]NERVA 2[/nomedia]

I don't want to throw the single vessel completely out, though.
I would like to see some station-building in this project, but launching and building a stack just takes too much focus away from the flight itself.

 

[Artlav]

That could be averted by using a single engine, as we probably were going to do anyway:
NERVA 2

Just in case, here is a DLL for that engine:
http://orbides.1gb.ru/orbf/nerva2_dll.zip
Comes with automatic thrust vectoring for compensating any load assymetry of docked vessels.
Looks like a good choice for an engine to build the vessel on.

How fast should the ship go?
With this engine and 4 tanks it's 364t, 290t of which is fuel.
So, it got 26km/s DV on it's own, 16 km/s of DV with 100t of payload, 9 km/s of DV with 300t of payload.
First is good for fast transfer, second is for slow. Reaction mass is whatever you shove into the tank, so taking one-way load is reasonable.

What i built as an experiment is:
-Nerva2+4 tanks
-Mir2 core
-self-deployed hab from the 60's
-Ravenstar
-Few shiny bits (tanks) from SSBB
-A full Tanker by Kulch
Adding up to about 300000kg of payload
This whole thing made it to Mars in a few months almost dry.

 

[Pablo49]

I would like to see some station-building in this project, but launching and building a stack just takes too much focus away from the flight itself.

We have to launch all those parts to Cook anyway (or would be just assume that was already done?) so why not make them into a functional stack like we have discussed before? And with Artlav's nerva .dll, it looks like this wouldn't be too hard to do.

 

[Bj]

We have to launch all those parts to Cook anyway (or would be just assume that was already done?) so why not make them into a functional stack like we have discussed before?

I was assuming so as well. Really it doesn't take that long to launch a few payloads by Ares. It will only take a while if we make this station really huge.

Just in case, here is a DLL for that engine:
http://orbides.1gb.ru/orbf/nerva2_dll.zip
Comes with automatic thrust vectoring for compensating any load assymetry of docked vessels.
Looks like a good choice for an engine to build the vessel on.

Perfect

Alright, Cook removed, Nerva added.

So what about a list of modules needed for this station?

 

[Urwumpe]

So what about a list of modules needed for this station?

At least a few of the inflatables from UCGO... never a bad choice.

Otherwise we modules that contain functions like:

• Green houses
• Med Bay
• Power supply, power storage
• Habitat
• Tool storage
• Rover garage
• Fuel storage
• In-situ fuel plant
• Water plant
• Communication
• Base command/Administration
• Meteological office
• Workshop
• Galley
• Recreation
• UMMU respawning :lol:
• Arnold Schwarzenegger for the terraforming project - With the sound "look, sa reacter is melting sa ice".

 

[Izack]

Alright, it looks like the stack is the best thing to do for now. I concede to your point.

I'm starting to wonder what we'll call this project. It has to have a cool name (on top of OFMM). I vote 'Project Sagittarius' in lieu of NASA's habit for naming things after constellations (Gemini, Orion, Constellation for crying out loud...)
I can't draw worth much, so how about someone come up with a mission patch?

Now, for the stack...
Excellent work on the NERVA2 dll, Astlav. I think we can scrap VesselStack. Still, for the sake of fuel economy we should still centre the COM as much as we reasonably can.
It's a gaseous fission reactor, so it will probably also act as the service module. Also, for radiation purposes, the habs should be way up at the front. Maybe a cupola right at the bow. That would be nice (although not much to see...pointing away from Earth at egress and away from Mars at insertion...maybe it should go on the side.)
I've included a very rough sketch using a tiny laptop finger pad thing.
To be clear, the red area in the middle would be where all of the parts for the station that aren't needed during the voyage would be held. Better to put them between us and the NERVA, eh? The red area farther astern could perhaps be a radiation shield?
* It may be better to place the landers parallel to the ship, on the sides, which I couldn't do with Paint or my dismal sense of perspective.

 

[Urwumpe]

I would just use the fact that the heavy masses (crew module, NERVA) are at the ends of the vessel and spin it in pitch or yaw plane for artificial gravity...

The landers would then be better put right behind the bridge, the the empty tanks are in the middle...and the rotation axis is pointed at Earth.

And the next time you plan to kick me out of the airlock, check command history of the onboard computer. There is a "SCHEDULE ECLSS_SHTDN PRIORITY 200 IN 600" waiting for you.

 

[Dambuster]

I seem to recall there was a deep space vessel addon made by French developers which included maintaining the vessel with built-in astronauts during a mission. Perhaps we could have something like that here (on second thoughts, since we'll be using UMMU, it would probably require a whole new addon...).

 

[Izack]

Ah, anyone get the NERVA2 working? I can't get it into the scenario...
I built a preliminary stack, just to demonstrate what I meant. It's just the rear section, as the other bits haven't been ironed out. I had to use a tanker instead of a NERVA, because it has an engine and propellant tanks and looks better than nothing. I don't want to be pushed to Mars by a tanker. I included two possible configurations. (The first one seems better, though.)

PS: Sorry, Urwumpe.

 

[Pablo49]

Once we have a definite name, I`ll whip us up a mission patch. I`ll probably wait until we get a more finalized stack, so I can include it. I have a few ideas going.

 

[Artlav]

Ah, anyone get the NERVA2 working? I can't get it into the scenario...

With my module you need to define it like that:

Nerva:nerva2
  STATUS Orbiting Mars
  RPOS -1963523.52 348526.54 3002937.30
  RVEL -2894.498 -251.111 -1859.285
  AROT 16.66 51.86 13.10
  PRPLEVEL 0:1.0
  NAVFREQ 0 0
END

Also, here is what my version looked like (677000kg/387000kg, 8.9km/s DV):

 

[Izack]

Stack concept No. 2 (Minus the NERVA2):
Feedback?

 

[Columbia42]

I think we're going about the design the wrong way here. What would be most efficient (in my opinion) is to have a central module where everything is stored (With the NERVA 2 behind it) and then have the hab modules on long tethers that will stretch out from the sides of the central module. A rotation around the Z axis will then produce artificial gravity. (I will post a pic of this later.) I also recommend that to save fuel, instead of making a Mars orbit insertion burn, we put a lightweight heatshield around part of the ship and skim through the outer layers of the Martian atmosphere (Like in "Mission to Mars.")

 

[Ashaman42]

For moving some of the cargo from martian orbit to the surface would a simple heatshield/capsule that could hold a number of ucgo cargos (be it 4 or 8 or whatever) work?

I'm not sure I could do it but I've heard that it's possible to be quite accurate using AerobrakeMFD (I think people were dropping cargo to earth from the shuttleA by dropping their orbit, releasing the cargo and then raising the PeA again before getting too deep into the atmosphere).

I'm thinking drop the hardy stuff and then either start the base wherever it lands or fetch the stuff via rover to where we want the base to be.

 

[Pablo49]

I like the new stack design, but assuming we would be putting the MSS modules in that open truss section, that could increase our mass beyond what the nerva can really handle, going off Artlav's research.

In regards to saving fuel on the insertion, didn't we already discuss having the Stack (though this was discussed with using the Arrow, but it can apply the same) bring machines and such to produce it's own fuel? With that, fuel efficiency isn't a major concern.

 

[Columbia42]

Actually, I just found this: View attachment Mars DRA 5.zip
(I had to compress it because it's a big file). Perhaps our OFMM could be modeled after NASA's plans for a Mars mission.

 

[Ashaman42]

Well I've got the code for my GDI miner and ore mill, either of these could be adapted to generate a fuel cargo instead. Either fuel from "thin air" like the miner producing rock or can require an input cargo like the mill in order to produce fuel cargo.

Or we could just make a Ucgo station that produces fuel to refuel ships directly.