New Release Interplanetary Modular Spacecraft RC9

[PeterRoss]

I bet it somehow connected with vector coordinates approximation.

---------- Post added at 19:10 ---------- Previous post was at 18:57 ----------

Note that you can integrate the engine when it's pointing in the wrong direction and when you burn it afterwards the flame is pointing in the wrong direction too. It's attachment point rotating. Please note also that Truss1to3used in this scenario is rotated 60 degrees before integration(dunno why). So we have sloped a.p. rotated before module's integration. And then the slope was translated to a fuel tank a.p.

---------- Post added at 21:13 ---------- Previous post was at 19:10 ----------

Here's the troublesome AP:

  ATTPOINT IM -6.0083,-3.4738,-33.9678 -0.8645,-0.5026,0 [COLOR=Red]-0.0043,-0.0025,1[/COLOR]

Note the rotation vector which is obviously incorrect.

---------- Post added at 22:16 ---------- Previous post was at 21:13 ----------

Confirmed. Defining rotation vector of any attachment point as [-0.0043,-0.0025,1] makes anything attached to it to rotate in the same manner.

---------- Post added 07-09-12 at 01:38 ---------- Previous post was 06-09-12 at 22:16 ----------

OBS construction continues:

The facility is mostly operational, only support systems are still off, main frame is almost completed. It's ready to accept its crew.

P.S. It would have been great to have docking port connected with animation for this facility - it could use a nice retractable docking mast. I don't ask for anything, just dreaming

 

[jedidia]

Confirmed. Defining rotation vector of any attachment point as [-0.0043,-0.0025,1] makes anything attached to it to rotate in the same manner.

So it is a normalisation problem. Now I just have to find out why it happens... Thanks a lot for the tests.

.S. It would have been great to have docking port connected with animation for this facility - it could use a nice retractable docking mast. I don't ask for anything, just dreaming

It would be a problem even if I supported it, for the reason that I can't force orbiter to update the relative position of a docked vessel. I.E. even if the dock port would change position, the vessel won't unless you undock and redock...

 

[PeterRoss]

What I meant is a mast with a docking port appearing along the longitudal axis of the station; when unneded it retracts and docking port just disappears making it possible for a vessel to pass through the cylinder. No need updating docked vessel, just undock it when mast starts retracting. But this feature isn't really that necessary.

 

[TerraMimic]

I think the XR5 does something similar with its docking port. I don't think you can dock with it if it is not extended. (I could be wrong though. I don't have access to orbiter right now to check it out.)

------------------------------- edit -------------------------------------

Ok, I checked it out. The docking port is still actually there. It is at the location of the extended docking tunnel. What appears to be happening, is that when you dock with it, you are immediately forcibly undocked from the ship. The effect feels like you bounce of the point where the docking port is supposed to be. That is what you want to happen, right?

 

[PeterRoss]

Yep. Either the docking port is deleted or just moved, it would be enough to just undock anything when animation is enabled - or just disable anuimation when the port is busy. The only thing that is not an option is to leave docking port at this place while visually it is retracted. There's little possibility that something will dock with XR5 port accidentally, but it's much more possible to hit the coaxial port in the cylindrical frame.

Anyway, this feature wasn't planned for R1 at all and I don't think there's much sense in making it. My facility is just a single instance, and you can't expect modular system to fit every single instance. I think I'll just make the docking mast a solid construction and the gates will be on just one end of the main frame.

 

[Loru]

What I meant is a mast with a docking port appearing along the longitudal axis of the station; when unneded it retracts and docking port just disappears making it possible for a vessel to pass through the cylinder. No need updating docked vessel, just undock it when mast starts retracting. But this feature isn't really that necessary.

Maybe not a solution but in my ISS Evacuation Shuttle it isn't possibler to dock until dockport cover is opened but it's made other way around - dockport exists all the time but when cover is closed vessel is forced to undock automatically.

 

[jedidia]

when unneded it retracts and docking port just disappears making it possible for a vessel to pass through the cylinder

Good luck with that...

Still, undocking and moving it out of the way would be possible. I'll keep it in mins for an update..

 

[Grover]

hey, been having a little play around with this, and i have a couple questions and some feedback:

first, the questions
1) how is the "Vessel's shadow" calculated, in relation to the radiators? it would be handy to know so i can put them somewhere that won't make the cooling system boil my crew

2)how are the resources handled? i haven't looked yet, but i imagine that oxygen is produced in certain modules, at the expense of power (and therefore heat generation etc.), but is the same true for food? and are all propellants universal? (so i could dock my XR5 to the station, and use it's excess fuel to top up the RCS tanks and main engine fuel of my space station)

3)ive read about an issue with CTDs when docking ports are deleted when vessels are "consumed" and added to the main vessel, is deleting docking ports necessary? admittedley, i havent read all of this thread, but surely deleting the target vessel completely would be easier, and you would still be able to copy its information to the source vessel (just an idea i'd had a while back for a project something like your own)


and now, a little feedback:

the level of detail and realism here is fantastic, certainly a must-have addon once the bugs can be digitally squished, but i've found a bug or two (and no, its not related to your excellent thermodynamics)

after my station consisted of two permanent (integrated) modules, a command module and a cooling module (i was experimenting ) i docked a truss module (the one that matches to a module at one end, and then has a perpendicular truss, i forget the designation of it), with one or two solar panels "docked" to the truss (Note: by dock i mean orbiter's standard of dock), when i integrate the truss module, i get a CTD (a regular thing i think)

now, when i reload the presaved scenario (nice idea by the way) for just before i added the truss, all the vessels in the scenario are invisible, including a stock ISS and Atlantis that were floating about someplace. if i enter the Atlantis' VC, i can see the ISS, but in any external view, all vessels become invisible (and i couldn't get them to re-appear, even by reloading the "Current state" scenario


hopefully you take it as positive feedback, i really like this addon/mod

well done!

---------- Post added at 12:50 PM ---------- Previous post was at 12:40 PM ----------

also, is there a short guide to making custom modules knocking about somewhere?

thanks

 

[PeterRoss]

2)how are the resources handled? i haven't looked yet, but i imagine that oxygen is produced in certain modules, at the expense of power (and therefore heat generation etc.), but is the same true for food? and are all propellants universal? (so i could dock my XR5 to the station, and use it's excess fuel to top up the RCS tanks and main engine fuel of my space station)

All consumables are being produced by lifesupport modules. Currently SBB41B modules named 'Lifesupport' produce air and water and 'Hydroponics' produce food, but it is just a matter of naming. The module type is what really counts. Any lifesupport module can produce any consumable resource if it is defined in its config.
As for fuel, propellants are NOT universal. There are several types of fuel, but you can add certain IMS-specific strings into XR5Vanguard.cfg file (not XR5VanguardPrefs.cfg, mind you!) and you'll be able to transfer appropriate fuel type between IMS and XR5 (or any other vessel's) specified tanks.

after my station consisted of two permanent (integrated) modules, a command module and a cooling module (i was experimenting ) i docked a truss module (the one that matches to a module at one end, and then has a perpendicular truss, i forget the designation of it), with one or two solar panels "docked" to the truss (Note: by dock i mean orbiter's standard of dock), when i integrate the truss module, i get a CTD (a regular thing i think)

now, when i reload the presaved scenario (nice idea by the way) for just before i added the truss, all the vessels in the scenario are invisible, including a stock ISS and Atlantis that were floating about someplace. if i enter the Atlantis' VC, i can see the ISS, but in any external view, all vessels become invisible (and i couldn't get them to re-appear, even by reloading the "Current state" scenario

Could you please post the troublesome scenarios here? It will be much easier for us to find the source of the problem.

hopefully you take it as positive feedback, i really like this addon/mod

well done!

also, is there a short guide to making custom modules knocking about somewhere?

thanks

Uh. I'm afraid no. I hardly can imagine guide on making module configs shorter than the one jedidia gave link to earlier (http://www.orbiter-forum.com/group.php?do=discuss&group=&discussionid=249)


EDIT: Please note that I haven't answered on some of your questions which will be better answered by Jedidia.

 

[Grover]

Great, and I'm getting the hang of how the parts are assembled too, maybe I can write up a walkthrough/guide at some point, to save you from concentrating on documentation

 

[jedidia]

now, when i reload the presaved scenario (nice idea by the way) for just before i added the truss, all the vessels in the scenario are invisible, including a stock ISS and Atlantis that were floating about someplace. if i enter the Atlantis' VC, i can see the ISS, but in any external view, all vessels become invisible (and i couldn't get them to re-appear, even by reloading the "Current state" scenario

I know the problem, but have no idea why it happens. Usually, zooming out really far and back in really close does the trick.

1) how is the "Vessel's shadow" calculated, in relation to the radiators? it would be handy to know so i can put them somewhere that won't make the cooling system boil my crew

Vessel Shadow is somewhat rudimentary, it only checks if another module finds itself in that rough direction. It doesn't take into account the actual size of the module.
Anyways, keeping radiators out of the sun usually is a matter of making the small cross-section face it, not the area. Pretty simple.

 

[Grover]

Vessel Shadow is somewhat rudimentary, it only checks if another module finds itself in that rough direction. It doesn't take into account the actual size of the module.
Anyways, keeping radiators out of the sun usually is a matter of making the small cross-section face it, not the area. Pretty simple.

so as long as i put them on the shadow side of a truss, and keep the sun above the station, ill be fine? how "general" is the direction that the module's CoG need be?

---------- Post added at 10:03 PM ---------- Previous post was at 08:50 PM ----------

has anyone found a sensible way to launch these modules manually? the XR5's inherent cargo suspends modules in the bay, clearly cheating, and Universal Cargo Deck, whilst allowing me to pack many modules in there, is incredibly unreliable, and drops certain modules whenever i load a scenario

are there any other ways to get these modules up there? how do you guys do it?

 

[jedidia]

so as long as i put them on the shadow side of a truss, and keep the sun above the station

As long as the radiating area doesn't face the sun, you're fine, yes.

 

[Grover]

and if i am a couple degrees out of perfect orientation, the heating effect on the radiators will be negligible (ish) right?

and i like your nice long config guide, all i'd ever need to know, perhaps i'll get on with my modules now, sure would be nice to assemble my own station from my own modules!

---------- Post added 09-08-12 at 01:42 AM ---------- Previous post was 09-07-12 at 10:39 PM ----------

i think i've found a rather peculiar math error in the solar panels:

from reliable sources, i can calculate that the total solar energy at LEO is approximately 1.37kW of solar power per square metre perpendicular to the sun's normal. I was working out how much solar panel space i needed for a craft, and given your incredibly pessimistic 6% efficiency of solar panels, i would need about 350m^2 of solar panel to power a self sufficient command module, with only a battery module and radiator for company

why are your solar panel efficiencies so low? we have achieved more than 45% efficiency from solar panels in laboratories, so 30% surely isnt too much to ask. perhaps the efficiency is 6% on the earth's surface in urban areas, but in space, the efficiency should be at least 30%

also, im putting together a detailed guide to working the addon, from the user's PoV, from the simple maths behind planning, to working the integration progress, ill post it up here when im done

---------- Post added at 02:01 AM ---------- Previous post was at 01:42 AM ----------

plus i can't get my head around these batteries, how is their maximum discharge calculated? i found that a small hab module discharged 700w, but thats it. i read in one place it is 5% of the capacity, and i read in another place that it is set to a default of 10kw if nothing is defined in the config.

seriously wish there was a good documentation now...

 

[jedidia]

from reliable sources, i can calculate that the total solar energy at LEO is approximately 1.37kW of solar power per square metre perpendicular to the sun's normal

It's almost 1.5, actually. Depends a bit on where the earth is in its orbit.

why are your solar panel efficiencies so low? we have achieved more than 45% efficiency from solar panels in laboratories, so 30% surely isnt too much to ask. perhaps the efficiency is 6% on the earth's surface in urban areas, but in space, the efficiency should be at least 30%

Unfortuately, space is counter-intuitive again... Solar panels in LEO seem to produce less, because they have to operate at higher temperatures (the efficiency of a solar panel drops with raising temperature, but this is not simulated in IMS). Anyways, I arrived at 6% by comparing the solar panel area of the ISS to its actual power output... You end up somewhere at 6% (a bit below, even, I think 5.8. And those things are actually double sided, which is another thing IMS doesn't simulate). So unless there's something critical I've missed, this is about where it's at currently.

plus i can't get my head around these batteries, how is their maximum discharge calculated? i found that a small hab module discharged 700w, but thats it. i read in one place it is 5% of the capacity, and i read in another place that it is set to a default of 10kw if nothing is defined in the config.

The second entry is outdated. Can you remember where you saw it?

 

[PeterRoss]

has anyone found a sensible way to launch these modules manually? the XR5's inherent cargo suspends modules in the bay, clearly cheating, and Universal Cargo Deck, whilst allowing me to pack many modules in there, is incredibly unreliable, and drops certain modules whenever i load a scenario

are there any other ways to get these modules up there? how do you guys do it?

I'm using Energia and Buran-T by Kulch, but it uses the same old UCD. What's your problem with it? I've never seen it 'dropping' anything.

 

[Grover]

I can't recall where I read it, I assume that it is 5% of the capacity?

My UCD bug drops certain items when a scenario is reloaded, as if the items weren't attached properly during loading

---------- Post added at 11:55 AM ---------- Previous post was at 10:14 AM ----------

ok, some quick research into space-based solar panels:

6% is indeed the most common at the moment (owing to the ISS having more solar panel area than any other LEO satalite), because it is ratehr cheap, and the ISS solar arrays were launched 12 years ago, so we can imagine that they were designed long before then, anywhere between the late 80s and mid-late-90s

since then, a number of new concepts have arisen, to increase solar power without cost:
firstly, exotic solar panels can indeed reach 30% efficiency rather easily, and reach a maximum of 45% for the REALLY exotic ones, however, they can cost ten times as much

one workaround is to make much smaller solar cells then necessary, and assemble them into the required solar panel area (leaving spaces between), then applying a concentrated photovoltaic system to concentrate the light into the small cells.

the concentration can be easily in the order of 500x the intensity of the incoming light, which means that we can reduce our solar cell area by over 20 times.

of course, the resulting solar panel is more expensive, and heavier than a more traditional solar panel of the same area, but has a much higher energy density, and would no doubt be required for any vessel larger than the ISS, to avoid using insane amounts of photovoltaic cells

its not a perfect solution, but it means that we can boost our efficiency to 30% reasonably feasibly (especially in orbiter, where there is no government or economics to get in the way)

ive already altered my own configs to allow a greater efficiency, i just thought you'd like to know that it is possible with current technology to get sensibly efficient solar panels

 

[jedidia]

Thanks, that's interesting information. Not sure yet if we're going to alter the included configs, as those solar panels are pretty much based on those old designs, but I'll keep it in mind.

I can't recall where I read it, I assume that it is 5% of the capacity?

Yes. Other than that, you can always look up your current maximum discharge in the specs screen.

ive already altered my own configs to allow a greater efficiency, i just thought you'd like to know that it is possible with current technology to get sensibly efficient solar panels

Generally, it is smarter to copy the configs and alter the duplicate, leaving the original intact. Otherwise people will run into compatibility problems real quick once they start sharing their vessels.

 

[cosmonaut2040]

Hi,
I built two moderately functional spaceships with this so far, having a lot of fun assembling and testing them. Thanks a lot again :tiphat:

Here is some hopefully constructive feedback:

- the NERVA engines in IMS produce way too much heat. As far as I understand their operation, NTR's cool themselves very efficiently: the LH2 propellant is also the coolant, and it doesn't need to circulate in radiators to radiate the heat, because the hot propellant is ejected out of the ship in form of exhaust. E.g. in this presentation: http://spirit.as.utexas.edu/~fiso/telecon/Borowski_6-27-12/Borowski_6-27-12.ppt you can see that NASA designs of spacecraft with NTR engines have almost no radiators at all.
This is different from nuclear reactors and NEP engines, where all the generated/consumed power has to be passed through internal mechanical and electrical systems, so they need to get rid of their waste heat through radiators.
On slide 18 of the above linked presentation you can see a schematic of a "bimodal" NTR, and the radiator is used only in the branch that generates electricity from the reactor, the propulsion branch has no radiator.
I fixed that by changing the efficiency parameter NERVA engine config file to 99.9999999 (although it is not completely correct - NTR does not really have such high efficiency, it's just that the waste heat doesn't get passed to the structure and the rest of the ship but is just ejected to space).
Also the ISP parameters and thrust-to-weight ratios of NTR's listed in the above NASA presentation are a bit more optimistic than the NERVA design in IMS.

- it would be nice to have a power cell as a another power generator option: consuming LOx+LH2 and producing power+H20

- it seems that batteries are not charged from external supply. I made a vessel powered only by batteries and when docked to another IMS ship, the docked vessel supplied just the exact power required to run the internal systems, but not to charge the batteries.

Cheers

 

[Grover]

Hi,

- it would be nice to have a power cell as a another power generator option: consuming LOx+LH2 and producing power+H20

isnt that what the ASTG module does? as far as i can tell, it makes its power from SOMETHING onboard (i can only assume that its fuel)