Decaying Orbits

[ZooNamedGames]

7 minutes ago, AlamoVampire said:

1. Limited fuel. They WILL deorbit. 

2. A meter is a meter sure. But at some point 1 becomes 2 becomes 4 becomes 8, 16, 32, 64, 128, 1km until burned up.

3. Its micro management no matter how you gussy it up.

Limited. The way I'm computing it- one 1m fuel tank will last you like 120 years in game. What would you need a probe longer for? You could walk every planet and still have several decades of orbital life left.

[Razorforce7]

@ZooNamedGames I agree with your aproach to realism. Everything to that end and you get a thumbs up. Since I'm full of critique on this one, you'll get a half thumb up for the aproach you seem to be having. But that is it xd.

Your idea or that of the OP is impossible. What values are going to be used concerning ionospheric aerodynamics? Even the mods like FAR do not have a completely accurate aerodynamics model (although definitely the closest)
How are the physics of aerodynamics and atmosphere being applied? Vessels are usually on rails in ksp above 70km.
And if Kerbin is going to have a upper ionosphere stretching beyond 70km then good luck on the physics. You'll have to find them physics experts first or a modder that is knowledged with the physics of orbital decay or I don't even want this.

Like I said earlier, vessels are on rails, this is how the game engine works and how it is programmed. I know you know this

You don't want them to be on rails? So they're active or deleted? Right??????
So every vessel in orbit around Kerbin (or wherever) is not on rails and thus active, right?????? (meaning we would have drastically lowered framerates xd)
I know this is not your idea, but hey, what is? On a more specific level I mean.

Oh, and like AlamoVampires said, this is ksp which is a 1/10th scale of the real solar system.

Orbiting 70km around Kerbin is, euh, I don't know exactly, but based on eyeballed horizontal circumerference I would say that is 500km altitude on Earth?
So 70km over Kerbin is let's say 500km above Earth. But both planets are based on the same aerodynamic properties?

Obviously the answer to my previous question is YES.
If you want to use the same atmospheric properties as a exact value compared to Earth then all that remains to be asked is how much atmosphere by weight/volume should be around Kerbin in relation to Earth. I think squad already did a good job at this.

However, eventually you will end up with a extended version of Kerbins atmosphere which is unrealistic. Or, you create a new atmosphere that is likely even more unrealistic.
And by likely I mean certainly. Because Kerbins atmosphere is unrealistic to begin with. Expanding it with additional properties like orbital decay is only going to expand the already unrealistic properties we are already experiencieng.

That said ^^^^^
It will be a experience of a noticeably different and unrealistic experience that is going to be extremely annoying for anyone doing multiple launches to Eeloo or other far of places while struggling to maintain the orbits of all your other 100+ sattelites.
Or find out later that you would have to correct the courses of all my sattelites around Kerbin and/or elsewhere as they drifted over the years.

A good realistic idea this is in the essence of which. But since Kerbal spaceprogram isn't realistic to the ends that are required it still isn't a good idea.



 

Edited April 29, 2017 by Razorforce7

[AlamoVampire]

@ZooNamedGames Even on EVA my kerbals can burn 5 units of rcs fairly fast when things go pear shaped. My ships when doing orbital ops can burn a 1m tank of lfo/ox in short order on even small nodes, so uh how do you figure a 1m tank of what fuel exactly? Lasts 120 years? 

8 rcs ports for balanced ops 4 ahead of com 4 aft, plus an orbital engine to get into finalized orbit, plus electronics and comms plus batteries plus rtgs and solar arrays, just top of me head

[tater]

Maybe they should just eliminate "suborbital" as a thing, since it's meaningless right now.

In general, they need the ability to do things to craft out of focus.

[RatchetinSpace]

I like the idea of encouraging players to maintain/replace space stations and satellites, but it doesn't fit KSP's playstyle.

Lets say you go away on an interplanetary mission (Which can be 60+ years if you're into gravity assists and such). When you finally return all your stations have spiraled inwards and crashed.

[Shadow Wolf56]

I disagree with this idea because, 

1- there is already one mod that does it.(RO)

2- it would be annoying having to keep your satellite in orbit by sending an orbital tug all the time. (especialy when you have a heap of sats.)

3- it would just be a constant workload and would be as boring as hell.

[TheKorbinjer]

Yes,

Orbital decay would be something i'd like to see, but you could have systems on your spacecraft that would maintain your sat/ station at the cost of fuel (perhaps Mono Propellant.) When the fuel runs out, then your orbit begins to decay.

 

Orbital decay would vary over your altitude (e. the higher you are, the less effect it has)

 

I hope squad/take2 implements it!

Edited June 2, 2017 by TheKorbinger

[LoSBoL]

No...

Unless...

It's toggleable, then I'd say...

No...

...Problem

Unless...

It takes an performance hit, then I'd say No again...

 

But more seriously, I see very little to nothing added to the gameplay, to me it's adding realism, just for the sake of realism.

 

 

[tater]

It would certainly add "gameplay," people who throw that out usually just mean it adds something they are not interested in, not that it objectively adds nothing.

Gameplay complexity is GOOD. Note that "gameplay" is not "user interface," or "player workload," etc.

Have station keeping a thing, and onboard RCS dead with it. That gives craft a lifetime. Station? Put a propulsion/boost module on it. Worried because you happily time warp 60 years with Jeb in KEO in a mk1 pod (because you don;t design anything that anyone could live in for years)? Out a huge file tank on your station. Every time an orbit drops by some number of km (as set by the player for that craft), and it raises the orbit to the set value at X expense of your props. Only have a decade of boost in the tanks? Don't time warp 60 years, it that really all that difficult?

Also, it seems like the only factor that matters at the KSP level of detail would be atmosphere, and there would at some point be a cutoff where it would not be worth considering. Stuff over several hundred km? No drag. Below that? Drag. Not terribly difficult to deal with.

Also, shouldn't craft with a periapsis below 70km deorbit? yes, or no?

[Alshain]

Frankly, the only way to have proper (read: predictable) decaying orbits would be to have N-body physics and that isn't going to happen.  You can't just randomly decay an orbit, it decays in a very mathematically predictable manner just like everything else we do in orbit.  You can't have that math without n-body.

[tater]

1 minute ago, Alshain said:

Frankly, the only way to have proper (read: predictable) decaying orbits would be to have N-body physics and that isn't going to happen.  You can't just randomly decay an orbit, it decays in a very mathematically predictable manner just like everything else we do in orbit.  You can't have that math without n-body.

This is true for the non-atmospheric drag issues. The only thing at our cartoon, KSP level of detail would be the atmosphere, I think, and the baseline case would be to at least have craft decay when they cross 70km.

[Alshain]

12 minutes ago, tater said:

This is true for the non-atmospheric drag issues. The only thing at our cartoon, KSP level of detail would be the atmosphere, I think, and the baseline case would be to at least have craft decay when they cross 70km.

Yeah, but if we were only talking about thin atmosphere at altitudes of the ISS for example (atmosphere that doesn't exist in KSP because of the hard 70km cut off), they would have to make a boost  once a year or so (if that).  The atmosphere is nearly inconsequential at that altitude.  The major reason for it needing to boost itself is because every time it whips by the Moon, it gets yanked toward it.  The large majority of an orbit's decay is because of the Moon. The Sun probably has more to do with it than the atmosphere.

As for decaying when it passes below 70k, I agree but that's just because of the on-rails mechanic.  That's done intentionally as a workaround.  It does decay properly if you stay focused on it.

Edited May 2, 2017 by Alshain

[LoSBoL]

8 minutes ago, tater said:

It would certainly add "gameplay," people who throw that out usually just mean it adds something they are not interested in, not that it objectively adds nothing.

Gameplay complexity is GOOD. Note that "gameplay" is not "user interface," or "player workload," etc.

Have station keeping a thing, and onboard RCS dead with it. That gives craft a lifetime. Station? Put a propulsion/boost module on it. Worried because you happily time warp 60 years with Jeb in KEO in a mk1 pod (because you don;t design anything that anyone could live in for years)? Out a huge file tank on your station. Every time an orbit drops by some number of km (as set by the player for that craft), and it raises the orbit to the set value at X expense of your props. Only have a decade of boost in the tanks? Don't time warp 60 years, it that really all that difficult?

Also, it seems like the only factor that matters at the KSP level of detail would be atmosphere, and there would at some point be a cutoff where it would not be worth considering. Stuff over several hundred km? No drag. Below that? Drag. Not terribly difficult to deal with.

Also, shouldn't craft with a periapsis below 70km deorbit? yes, or no?

You are right, I'm not interested, that's why I started with No... Unless it's toggleable. For me personally, I don't want to keep fiddling to keep my vessels in space, hence the toggleing.
I don't see it happening at all though, the strain of physics calculations is already off the charts, adding even more stress just to have a realistic orbital decay certainly won't add to the gameplay

[tater]

5 minutes ago, Alshain said:

Yeah, but if we were only talking about thin atmosphere at altitudes of the ISS for example (atmosphere that doesn't exist in KSP because of the hard 70km cut off), they would have to make a boost  once a year or so (if that).  The atmosphere is nearly inconsequential at that altitude.  The major reason for it needing to boost itself is because every time it whips by the Moon, it gets yanked toward it.  The large majority of an orbit's decay is because of the Moon. The Sun probably has more to do with it than the atmosphere.

As for decaying when it passes below 70k, I agree but that's just because of the on-rails mechanic.  That's done intentionally as a workaround.  It does decay properly if you stay focused on it.

Yeah, for KSP, I just want stuff that would decay IN focus to decay OUT of focus. 

I'd be using principia already if there was a mac build of it  .

[panzer1b]

For very low orbits (as in under 70km, or maybee even up to around 100km) id support something like on-rails deorbiting, provided it does NOT take any noticeable performance hits to do so.  Above that i dont want any mechanic that imposes any form of "lifetime" on a vessel, i dont care how realistic or whatever it is, if it renders vessels useless after a certain amount of time im going to disable it/mod it out.

Now i have nothing against the concept, its just one of those "tedious" things like the not too long ago comm net system (screw you commnet, the droid brains on my starships are powered by sentient AI and dont need some command signal to operate) that id just turn off, and since i have no interest in tediousness and only really enjoy building military vessels in this game and having battles with them (both stock and occasional BDA for planes/tanks), i dont feel the time and effort spent to make this feature work is worth it when they could spend that time adding something (or just fixing the game) that would be more universally accepted.

I completely understand why teh "realism" people like and want this idea, and it would add to gameplay complexity, but i just fail to see why such a controversial feature should be developed when there are already mods out there that do this concept (im pretty sure there is something in RO that adds N-body physics and has orbital decay added to the game in some form).  For now, those that want it can stick to mods, i highly doubt its possible for squad to introduce this without a performance hit, and if we have to have a performance hit and really want orbital decay, just get the mod and be less unhappy.

[cpx]

Yes but only as part of RSS difficulty which does not exists in game.

[KingDominoIII]

No! That requires simulation of Lagrange points and N-bodies and would kill all but supercomputers.

[regex]

2 hours ago, KingDominoIII said:

No! That requires simulation of Lagrange points and N-bodies and would kill all but supercomputers.

Principia and my laptop would like a word with you.

Also, what does atmospheric drag have to do with N-body orbital calculations?

I like this idea for the base game, especially if there is a cap on the altitude where it can happen, maybe based on scale height. Two or three scale heights max, drag increasing based on "depth", nothing too severe, just enough that you'll notice when your "Sputnik" degrades after a year but not enough to touch anything that serves the solar system. The drag would be pretty minimal but would necessitate higher parking orbits for interplanetary vessels that would hang around for more than a week or so.

[Alshain]

1 hour ago, regex said:

Also, what does atmospheric drag have to do with N-body orbital calculations?

Nothing.  It was two different concepts of "orbital decay" that were being discussed.  One topic was about unloaded objects having atmospheric drag (technically not orbital decay because it's not orbit) and the other was actual orbital decay (n-body).

Edited May 30, 2017 by Alshain

[regex]

On 5/2/2017 at 9:56 AM, Alshain said:

Yeah, but if we were only talking about thin atmosphere at altitudes of the ISS for example (atmosphere that doesn't exist in KSP because of the hard 70km cut off), they would have to make a boost  once a year or so (if that).  The atmosphere is nearly inconsequential at that altitude.  The major reason for it needing to boost itself is because every time it whips by the Moon, it gets yanked toward it.  The large majority of an orbit's decay is because of the Moon. The Sun probably has more to do with it than the atmosphere.

Do you have a citation for this I can read? I can't find anything that states the ISS has to make a boost burn because the moon affects its orbit, everything I've seen points to atmospheric drag being the major force of orbital decay in low Earth orbit (below 1200km).

46 minutes ago, Alshain said:

Nothing.  It was two different concepts of "orbital decay" that were being discussed.  One topic was about unloaded objects having atmospheric drag (technically not orbital decay because it's not orbit) and the other was actual orbital decay (n-body).

If the orbit decays from whatever force then it is actual orbital decay. But it sounds like that discussion was about orbital perturbation from another body's influence.

[Adelaar]

Please note that currently, if a orbit is suborbital but above 19 km, there isn't a decay calculated AT ALL. This can be extremely frustrating when leaving space debris in a suborbital flight path but it doesn't crash.

I also remember the orbital decay bug which lingered in the game after 1.0. The decay in that bug was pretty extreme, in the order of 1m/s in decay, but still a great bore and killed much of the fun in building a space station.

Nevertheless, the suggestion isn't a bad one, it's a good one actually. However, I can only see it come to life IF the following suggestions (which have in part already been mentioned, so I shall paraphrase) are implemented:

1. This should be an option, and reserved for the more experienced players.

2. This process should be automatic, so in stead of an orbital decay you'd see a drainage in RCS or LFO.
2a. This will also mean that Fuel levels should be visible from the space center, and a low fuel warning should be given when reserves are low so that people can start a refueling mission or just let the thing run dry and start to decay.
2b. This would ultimately lead to Squad having to implement a decay function while the vessel is not in view. Otherwise, they would still be hanging in the air like they always do, until you view the sat personally.

3. The orbital decay should be limited in effect, and depending on the size of the craft. I'd suggest that anything above 400-500km (Kerbin) should not suffer from decay, to make things less tedious.

Needless to say, this requires a whole lot of extra coding (and possible bugs) so I don't think that Squad will resort to implementing this function. To calculate all the decays of all the space objects can become quite gruesome for a pc, as it has to be done realtime (even when focussed on another object). This will possibly hurt the performance and for such a trivial matter as orbital decay it is hardly worth the effort. I'd be happier when weather (including wind) is implemented in the game, as that mechanic is more demanding as well as rewarding.

[NSEP]

No, not in stock, unless its a on/off feature.

As a mod? Yes! I would love to see that!

KSP is not supposed to be super realistic. If orbital decay gets added we might just implement Realism Overhaul in stock.

Edited May 30, 2017 by NSEP

[Alshain]

9 hours ago, regex said:

If the orbit decays from whatever force then it is actual orbital decay. But it sounds like that discussion was about orbital perturbation from another body's influence.

Well, if it isn't in orbit, it's not.  You can't have orbital decay from a suborbital trajectory.  Yes, one of the conversations was about orbital perturbation.

Edited May 30, 2017 by Alshain

[regex]

5 minutes ago, Alshain said:

Well, if it isn't in orbit, it's not.  You can't have orbital decay from a suborbital trajectory.

Then what would an N-body simulation dealing with lagrange points have to do with a suborbital trajectory?

[Alshain]

10 minutes ago, regex said:

Then what would an N-body simulation dealing with lagrange points have to do with a suborbital trajectory?

Nothing, it was two different conversations happening at the same time.  Try to keep up