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Question about new physics


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6 hours ago, shdwlrd said:

Patched conics with limited n-body simulation

Wasn't there something about Rask/Rusk situation being re-worked, because there were problems with n-body? It might be just patched conics throughout the game.

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11 minutes ago, K^2 said:

Wasn't there something about Rask/Rusk situation being re-worked, because there were problems with n-body?

Never happened unless there's a source.

11 minutes ago, K^2 said:

It might be just patched conics throughout the game.

Patched conics just won't work around Rask and Rusk lest the game ends up feeling amateurish.

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1 hour ago, pandaman said:

I seem to recall reading that they came up with a special solution if some sort for Rask and Rusk, but it's patched conics otherwise.

Speaking of rask and rusk,  how the hell do you orbit one of them? do you orbit both at the same time? one at a time? figure 8 orbit?

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On 10/7/2021 at 12:59 PM, Staticalliam7 said:

Will KSP2 still use  patched conic approximation for orbital physics [...] Speaking of rask and rusk, 

You can hear some of the KSP2 developers' goals in this interview by Scott Manley (youtube link)

Scott started to suggest solving the "restricted n-body problem" where celestial bodies are "on rails" in their Keplerian orbits, and craft move under the gravity of all 'n' of them.  

Listening to the appropriately non-technical answer from the creative director of KSP2, I would guess they will simulate the "restricted 3-body problem" only in the neighbourhood of Rask and Rusk.  (They accepted the challenge of computing trajectories of craft under long periods of constant thrust, which is similar to computing the trajectory of a craft under two moving centres of gravitational attraction.) 

That would, as you say, make orbiting the binary very interesting, and interesting in a way that seems to suit what KSP players enjoy, so I hope they do simulate the more complicated Physics here.

[Edit: There is a clear answer in the obvious place, the KSP2 Developer Diaries:
" in the case of Rask and Rusk, we’ll be calculating the gravitational pull of multiple bodies on our Kerbal vessels, so that developing a stable orbit in complex conditions like a binary planet system becomes a new and exciting challenge! In addition, attempting a landing on Rask or Rusk will be a different experience depending on the location of the sister planet in relation to your target for touchdown, and yes, there will be an astable Lagrage point between the two planets (if we pull this off correctly)." ]

Edited by OHara
noticed a direct answer from the developers of KSP 2
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14 hours ago, K^2 said:

Wasn't there something about Rask/Rusk situation being re-worked, because there were problems with n-body? It might be just patched conics throughout the game.

If there's going to be even remotely realistic flying with Rask and Rusk, and I expect there will be because the devs have said there will be lagrange points, KSP 2 is at least going to have some kind of a system to model what's called restricted three body. Rask and Rusk may have a rigidly defined sphere of influence where patched conics apply outside and restricted three body applies inside. With restricted three body, both Rask and Rusk are on rails but the force they apply on your ship is a vector sum of Newton's law of gravitation i.e. "Gm1m2*r^-2". These two forces will be applied as impulses from iteration to iteration, thus effecting the motion of your ship. Due to there not being infinite accuracy in the values which describe your ship's motion, there will be a chaotic factor for values of time far into the future.  In this video, you can imagine your ship as the yellow dot and Rask/Rusk as the pink and blue dots. Only with the same mass in KSP 2.

 

In short it means that Rask will have a gravitational pull on your ship, and Rusk will have a gravitational pull on your ship, but neither Rask nor Rusk will pull on each other and your ship will be incapable of exerting its miniscule force on either planetoid. I'm no programmer but I imagine that if intercept came up with a working solution for restricted three body, they may be able to generalize and be able to do restricted n-body as well.

 

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18 hours ago, K^2 said:

Wasn't there something about Rask/Rusk situation being re-worked, because there were problems with n-body? It might be just patched conics throughout the game.

In the audio interview they revealed rask/rusk will be n-body within the pairs SOI (so 3-body)

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3 hours ago, Pthigrivi said:

One basic question is axial tilt confirmed?

I believe it was. Can't give you a valid source though, I think it was mentioned in one of the early interviews. 

You could search the forums if you like, maybe it's out there somewhere.

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8 hours ago, The Aziz said:

I believe it was. Can't give you a valid source though, I think it was mentioned in one of the early interviews. 

You could search the forums if you like, maybe it's out there somewhere.

You are right, thats was mentioned in early inrewiev. We do not know is it still a thing, but hope if they mentioned it, then that's true. 

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There's an early interview with a video game magazine (link) that was discussed on the forum here, covering a bit about how KSP2 plans to simulate Physics, including axial tilt for planets.  I would not be as excited about axial tilt as they were in that thread.

KSP1 constrains all the rotation axes of planets to be all parallel.  There is axial tilt in the sense of the planet's rotation being tilted from the plane of the orbit, and thus seasons, but only as a side effect of orbital inclination.  Moho's north pole gets a bit less hot in winter, and Eeloo's a bit less cold in summer.   Real Solar System gives Earth the correct axial tilt relative to its orbit, but the other planets have whatever tilt follows from their inclination and the constraint to rotate along the same axis as Earth.

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On 10/7/2021 at 12:59 PM, Staticalliam7 said:

Speaking of rask and rusk,  how the hell do you orbit one of them? do you orbit both at the same time? one at a time? figure 8 orbit?

You don't. You'll have to be just above the atmosphere or in a distant orbit. It isn't that complicated of an issue. and I'm not sure how a figure 8 orbit works in your head because that would require several bodies in a perfect balance.

12 hours ago, The Aziz said:

I believe it was. Can't give you a valid source though

Don't get how it's confirmed without a source

13 hours ago, mcwaffles2003 said:

In the audio interview they revealed rask/rusk will be n-body within the pairs SOI (so 3-body)

I did doubt that, with KSP having its own system wide N-body mod (Principia), that a bunch of very skilled devs working on the game from the ground up would have trouble with localised 3-body, and part with something like patched conics as horrible as it is beyond the simple configurations KSP 1 has.

Edited by Bej Kerman
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3 hours ago, Bej Kerman said:

Don't get how it's confirmed without a source

You can go look for it if you're willing to listen to multiple interviews in search for one sentence. I can't be bothered, just recall things from my own memory because I know I've heard it somewhere.

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21 hours ago, The Aziz said:

You can go look for it if you're willing to listen to multiple interviews in search for one sentence. I can't be bothered, just recall things from my own memory because I know I've heard it somewhere.

From that 1.5 hour long podcast. Somewhere in the first 30 minutes if I recall correctly.

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