Decaying Orbits

[ZooNamedGames]

9 hours ago, KingDominoIII said:

Because every object pulls others towards it with its gravity, an N-body cakcuoation must be used to accurately simulate orbital decay. Orbital decay can occur due to other forces outside the sphere of influence.

Granted it's harder to simulate and easier for players to just park above X height and ignore the issue altogether. 

[tater]

12 hours ago, KingDominoIII said:

Because every object pulls others towards it with its gravity, an N-body cakcuoation must be used to accurately simulate orbital decay. Orbital decay can occur due to other forces outside the sphere of influence.

This is why some of us suggest only dealing with atmospheric drag, and not n-body stuff.

[Guest]

12 hours ago, KingDominoIII said:

Because every object pulls others towards it with its gravity, an N-body cakcuoation must be used to accurately simulate orbital decay. Orbital decay can occur due to other forces outside the sphere of influence.

Nowhere in OP was there a suggestion of an "accurate simulation". In fact, the OP suggestion barely even gives nod to realism given how quickly orbits degrade. The major force of orbital decay in LEO is atmospheric drag and outside of LEO is things like radiation or solar wind, and while an N-body solution may result in orbits that are collisions that is more properly a "perturbation" (because it can result in any number of vector changes), not "decay" (which is a general loss of orbital energy).

Edited June 1, 2017 by regex

[John FX]

2 hours ago, tater said:

This is why some of us suggest only dealing with atmospheric drag, and not n-body stuff.

I would just want a graduated atmosphere above 70km where decay would happen, up to 1000km or so, for gameplay not realism reasons. Over 100km it should take years for a craft to burn up.

[Combatsmithen]

I think there is a mod for this guys. Called Orbital Decay or something. Just look up  KSP Orbital Decay mod or something like that

[Guest]

16 minutes ago, Combatsmithen said:

I think there is a mod for this guys. Called Orbital Decay or something. Just look up  KSP Orbital Decay mod or something like that

That's great, thanks. We're discussing a suggestion for the base game here, have any ideas?

[Combatsmithen]

52 minutes ago, regex said:

That's great, thanks. We're discussing a suggestion for the base game here, have any ideas?

No. Orbital decay will probably never be added to the base game, but there is a mod for that, usually in KSP if there is something that's not in the base game, there is a mod for it. And not everyone wants orbital decay in the base game, so you can mod it yourself

Edited June 1, 2017 by Combatsmithen

[Guest]

6 minutes ago, Combatsmithen said:

No. Orbital decay will probably never be added to the base game, but there is a mod for that, usually in KSP if there is something that's not in the base game, there is a mod for it. And not everyone wants orbital decay in the base game, so you can mod it yourself

But we're discussing a suggestion for the base game. Whether there's a mod for that matters little except to those who want that now, what matters is this suggestion. If you don't like the suggestion that's fine, but telling people not to make the suggestion because they can mod it is pretty ... condescending and rude, tbh.

[tater]

18 minutes ago, Combatsmithen said:

No. Orbital decay will probably never be added to the base game, but there is a mod for that, usually in KSP if there is something that's not in the base game, there is a mod for it. And not everyone wants orbital decay in the base game, so you can mod it yourself

This sub forum is explicitly for suggestions to the stock game. Anything about mods belongs elsewhere, except perhaps suggesting existing mod functionality be added to the stock game.

Your post is like replying to a thread about creating a replica Apollo in the stock game with a picture of an Apollo mod Apollo, and saying "there's a mod that makes a 100% accurate Apollo!" True, but utterly beside the point.

[juanml82]

On 29/4/2017 at 2:22 PM, tater said:

Again, so what? Put it in a higher orbit. Getting to any orbit in KSP is trivial. If it takes an extra couple of launches to fill a depot or whatever, that's just tough.

KSP lacks a few things that create interesting design challenges. Since apparently large numbers of players never leave Kerbin SoI, increasing the interest/fidelity at home (Kerbin) makes a lot of sense. I'd like to see multiple propellant choices instead of just 2 (LFO/Mono), with actual trade offs. Maybe LFO/cryo (with boiloff)/hypergolic with mono as RCS. Have some tiny % chance that the first 2 might not restart, hypergolic always works. LFO has a tiny failure chance and lower I_sp, cryo has boiloff (and a way to mitigate at cost in mass/power/funds), but higher  I_sp. Hypergolic props are reliable, but have a different I_sp. 

Bottom line is that complexity in design choices is a good thing. As long as the decay risk is limited to a certain range of orbits for simplicity. I'm always annoyed when I have junk that should decay and I have to clean it manually.

A good game is a sucession of interesting choices. If your engines don't restart, you don't have a choice to make. You've lost and there is nothing you can do about it. It's like having a piece of armor or a weapon that randomly vanishes in an RPG or FPS. It's not a good design choice for a videogame, even if it's a consideration real engineers can have.

If you want both orbital decay and avoid micromanagment, you also need a game element to automate station keeping. You make a satellite and add enough fuel and an engine so it can last x years. So you add a game element to cause a failure, another to negate it and you end up where you've started. KSP is consuming more CPU cycles, man hours have been spent in designing it, and the gameplay remains the same.

On 29/4/2017 at 5:50 PM, ZooNamedGames said:

No, but a meter is a meter. That hasn't changed.

It's not micromanagement if you let them station keep themselves.

If they can do the station keeping themselves, what's the point to have this dynamic in the first place?

On 30/5/2017 at 4:29 PM, tater said:

Simple question: If you leave a spent tank with an apoapsis of 50km above Kerbin, do you think it should remain in orbit forever, yes or no? If you think yes, then they might as well do away with the atmosphere altogether. If you think it should decay and reenter at some point, then we are only quibbling about the details.

I don't care, because you're incredibly unlikely to accidentally rezvendous with debris, let alone get hit by one. And if I want debris to dissapear while I'm not looking, I lower the amount of debris.

 

Also, did someone calculate what's Kerbin's Karman line? Is it really 70km?

[Gaarst]

Didn't read the whole thread, but I agree with what @juanml82 said about orbital decay: we need a way to automate it, keeping dozens of satellites in orbit would be a real pain. About the engines thing, don't make it random: even though random failures are a thing, you can just revert in KSP; the only error that should cause a mission to fail should be engineering or piloting, not a coin toss. Though I do support more realism in engine workings.

45 minutes ago, juanml82 said:

Also, did someone calculate what's Kerbin's Karman line? Is it really 70km?

About 62.2km.

Edited June 2, 2017 by Gaarst

[Guest]

I don't think station keeping should be automated but I do think atmospheric drag should be limited to under a few extra scale heights and work just like drag does now only on rails. Maximum altitude of the effect around 90~100km, I think. Maybe leave it as sliding scale so people can use it to alter debris disposal on rails but nothing else or experience dealing with space station station-keeping... I don't think this belongs above 250km; I don't know the math but I doubt the effects would be noticable for years above that altitude.

I don't see this affecting any but a small minority of satellites. And if it did affect geosynchronous sats or something then that's all the more reason to put a new one up after a few years, maybe by a contract designed to pay for replacing decaying sats.

[OrbitalBuzzsaw]

8 hours ago, regex said:

I don't think station keeping should be automated

 

Are you mad?

[Brent Kerman]

9 hours ago, regex said:

I don't think station keeping should be automated but I do think atmospheric drag should be limited to under a few extra scale heights and work just like drag does now only on rails. Maximum altitude of the effect around 90~100km, I think. Maybe leave it as sliding scale so people can use it to alter debris disposal on rails but nothing else or experience dealing with space station station-keeping... I don't think this belongs above 250km; I don't know the math but I doubt the effects would be noticable for years above that altitude.

I don't see this affecting any but a small minority of satellites. And if it did affect geosynchronous sats or something then that's all the more reason to put a new one up after a few years, maybe by a contract designed to pay for replacing decaying sats.

I totally agree with this post.

[tater]

14 hours ago, juanml82 said:

A good game is a sucession of interesting choices. If your engines don't restart, you don't have a choice to make. You've lost and there is nothing you can do about it. It's like having a piece of armor or a weapon that randomly vanishes in an RPG or FPS. It's not a good design choice for a videogame, even if it's a consideration real engineers can have.

A good set of choices doesn't always mean having a choice at every moment. If your rocket explodes, do you think you should have an "unexplode" choice? The choice in that case was made in the VAB, not in flight. Take restarting engines---this is an excellent example. If you have realistic limitations (need not be RO for stock, but a watered down version), then the design choices matter in a way they don't in stock KSP. One type might be cheaper, and have more thrust, but it doesn't throttle much. Another might not restart many times. The best Isp choice has boiloff as an issue.

It's not random, it is a set of constraints that make design challenges more interesting---and it offers more choice. 

A simple thought experiment would be some sort of "space race" challenge in a stock KSP with limited funds and science points to unlock stuff. With meaningful trade offs for different engine choices (and to stay on topic, with very low Kerbin orbits decaying), then you could see 10 different players come up with almost as many mission architectures to complete the challenge. As it is, we'd all make a mk1 pod on top of a small stack since there is in fact an optimal design at lowest price because there are literally no trade offs. That's poor game design. I'd usually go off on the solar system scale here, because since most players don't leave Kerbin SoI, the Mun would be more interesting if staged landers were a meaningful trade-off/solution.

Quote

If you want both orbital decay and avoid micromanagment, you also need a game element to automate station keeping. You make a satellite and add enough fuel and an engine so it can last x years. So you add a game element to cause a failure, another to negate it and you end up where you've started. KSP is consuming more CPU cycles, man hours have been spent in designing it, and the gameplay remains the same.

This is entirely unneeded for the atmospheric drag issue. Reboosting would not happen often, and the simple solution would be a higher orbit. 

Edited June 2, 2017 by tater

[Guest]

3 hours ago, OrbitalBuzzsaw said:

Are you mad?

No, are you?

Given a wide range of options for the player I see no reason for the feature to be made meaningless by automating it away.

[KSK]

4 hours ago, OrbitalBuzzsaw said:

Are you mad?

I'm maybe a bit out of touch but I recall starionkeeping already being a thing with satellite constellations unless you have a lot of patience setting up your orbits or just edit the persistence file. Oh - and there's doubtless a mod for handling it too - somehow there always is.

I really don't see atmospheric drag being a big deal for stationkeeping especially if you can avoid the problem altogether by boosting to a higher orbit.

[juanml82]

15 hours ago, Gaarst said:

Didn't read the whole thread, but I agree with what @juanml82 said about orbital decay: we need a way to automate it, keeping dozens of satellites in orbit would be a real pain. About the engines thing, don't make it random: even though random failures are a thing, you can just revert in KSP; the only error that should cause a mission to fail should be engineering or piloting, not a coin toss. Though I do support more realism in engine workings.

About 62.2km.

So we already have orbital decay between 62.5 and 69.9 km

3 hours ago, tater said:

A good set of choices doesn't always mean having a choice at every moment. If your rocket explodes, do you think you should have an "unexplode" choice? The choice in that case was made in the VAB, not in flight. Take restarting engines---this is an excellent example. If you have realistic limitations (need not be RO for stock, but a watered down version), then the design choices matter in a way they don't in stock KSP. One type might be cheaper, and have more thrust, but it doesn't throttle much. Another might not restart many times. The best Isp choice has boiloff as an issue.

And we're back at Harvester's original trial and error: you get to do things in the VAB which will have consequences that you can't predict. That's fine for someone playing single missions in LKO. But if you're sending a fleet to Jool? You create 8 different vessels. You send each of them in a long transfer to Jool. While they are travelling, you handle your Eve and Moho missions. Finally, KAC lets you know the ships are beginning to enter Jool's SOI. Everything goes well until a random coin toss makes your tanker fail to restart its engines as it approaches its suicide burn for landing on Vall. And there is nothing you can do about it.

 

Take an RPG instead. You can focus on developing your one handed skills or your two handed skills. One-handed swords have specific pros and cons you (should) know from the get go, the same applies for two handed swords. As the game progresses, maybe there are special one handed swords you can't take advantage of if you leveled up your two handed skills as well. However, what will never happen is your swords vanishing in the middle of a dungeon.

[tater]

4 minutes ago, juanml82 said:

So we already have orbital decay between 62.5 and 69.9 km

We do?

I can load up, and put a craft with periapsis there right now, and time words it forever, will my craft deorbit, yes or no? If it doesn't happen out of focus, there is no decay.

4 minutes ago, juanml82 said:

And we're back at Harvester's original trial and error: you get to do things in the VAB which will have consequences that you can't predict. That's fine for someone playing single missions in LKO. But if you're sending a fleet to Jool? You create 8 different vessels. You send each of them in a long transfer to Jool. While they are travelling, you handle your Eve and Moho missions. Finally, KAC lets you know the ships are beginning to enter Jool's SOI. Everything goes well until a random coin toss makes your tanker fail to restart its engines as it approaches its suicide burn for landing on Vall. And there is nothing you can do about it.

The choice would be to take an engine that cannot fail to restart, even though it has lower Isp. The choice might be to make a transfer stage with multiple engines, so that if one fails, you have a backup. If the player is dumb enough to put all their eggs in one basket, then yeah, they might have an issue. Of course any part failure mechanic would be 99% a career thing, anyway. What's the point of a career mode like we have now with ZERO change of failure? (I don;t mean part failure, I mean "losing" the game---your program fails, and is shut down. 

 

4 minutes ago, juanml82 said:

Take an RPG instead. You can focus on developing your one handed skills or your two handed skills. One-handed swords have specific pros and cons you (should) know from the get go, the same applies for two handed swords. As the game progresses, maybe there are special one handed swords you can't take advantage of if you leveled up your two handed skills as well. However, what will never happen is your swords vanishing in the middle of a dungeon.

You leap a chasm, and drop your sword. Your sword just vanished, now you need to improvise.

An RPG analogy to KSP right now is hard to come up with, other than "RPGs" that allow respawn (instantly any such game in not role playing, unless your character is immortal). KSP in career is impossible to lose short of actively trying to fail.

[juanml82]

6 hours ago, tater said:

You leap a chasm, and drop your sword. Your sword just vanished, now you need to improvise.

An RPG analogy to KSP right now is hard to come up with, other than "RPGs" that allow respawn (instantly any such game in not role playing, unless your character is immortal). KSP in career is impossible to lose short of actively trying to fail.

Example: Skyrim. You fight certain enemies, they use a shout that disarms you. You can get your sword back from the ground, you can retort to destruction magic, you can use a shout that makes you temporarily invulnerable, you can run and let a follower or conjured daedra deal with the enemy. Which one you take also depends on the skills you've leveled up before that point.

However, if your engine fails to start when you're landing on Vall, your ship will crash. There is nothing you can do to avoid it. Hence, lack of choice.

 

KSP, since career, has plenty of RPG elements: contracts are side quests (there is no "main quest"), science is xp points, the tech tree is levelling up, "finish this quest" is "finish this mission". And you can not fail the career, but you can fail your individual missions.

[tater]

What if your sword, you know, breaks.

If that's not a thing, it's not roleplaying, it's a FPS game with powers, etc.

Roleplaying is "dead is dead."

[Guest]

Can we bring the topic back to space?

NASA put three ion engines on Dawn, a long-duration exploration spacecraft, because they expected failures. Many spacecraft carry multiple redundant reaction wheels. That is appropriate in terms of design decisions to what would happen with failures in KSP.

[Alshain]

Can we bring the topic back to the topic?

If the added decay due to nbody gravitationnal perturbation, then yes we would need automated stationkeeping.  I certainly don't want to have to correct my sats every time I timewarp my ships. However I think such a feature doesn't belong in this game.

Decay due to atmosphere would not need station keeping.  You wouldn't station sats in the atmosphere.  This would just help clean up debris more than anything.

Edited June 4, 2017 by Alshain

[Vinhero100]

If they were adding this in the game, they should make it for debris only.... 

[KSPFanatic102]

On 05/06/2017 at 1:35 AM, Vinhero100 said:

If they were adding this in the game, they should make it for debris only.... 

Good point