Axial tilt for planets

[Kasuha]

Okay, I know this has been suggested already as it has link in the Already Suggested thread but that thread is closed, posting to it would be necroing even if it wasn't and I don't really see axial tilt suggestions on WNTS list anymore as claimed in the mod's closing post in the linked thread. So I thought I could add some of my ideas I had about it.

Of course as one of those "realism-related" suggestions there's a question if we really need increased difficulty in the form of difference between ecliptic and equatorial planes. My opinion on it is, the difference is not that big to become serious obstacle for players and it might improve on the fact that a lot of players are clearly too addicted to equatorial orbits.

Then there is of course the problem: current perfect alignment of Kerbin's rotational axis with Mun's orbital plane makes it easier for newbies to get to orbit and visit some other (atmosphere-free) body before they learn how to use more complex maneuvers.

But on the other hand, even for newbies Minmus is the easier target than Mun because of its low gravity. So for newbies it's now either go to Mun with its higher gravity and fuel demands, or go to Minmus with its inclination.

My proposal is:

- implement support for axial tilt into the game (obviously)

- give Kerbin some axial tilt, say 10-15 degrees

- put Minmus in orbit lying exactly in Kerbin's equatorial plane. That will give newbies their easy target, despite the fact that it is more distant

- give Mun orbit some (slight) tilt so there's not an eclipse every few days (it is fun the first few times but then it turns to great annoyance whenever you run anything with solar cells; it will be more fun if it will be rarer)

- for simplicity, leave Sun and Jool's axial tilt at zero.

- change other bodies' tilt suitably

- navball should always follow axial tilt of the SOI's central body (i.e. North should point in the body's North direction etc)

- map view should be always in the system's ecliptic plane

Yes, it would mean that to go interplanetary, you'll need to learn to launch to the ecliptic plane rather than to equatorial plane. Yes, it is a bit of additional challenge. But in my opinion a very small bit that would improve the impression without having any significant negative impact.

[regex]

This needs to happen, especially if KSP is to be considered a teaching tool. This is an important consideration when launching IRL.

[Sirrobert]

I think we should keep Kerbin without tilt (though I like your idea of matching it with Minmus), for simplicity sake

The rest, I agree

[technicalfool]

Also if more planets eventually get added, can we have a lop-sided gas or ice giant like Uranus? That could make visiting any moons around it a bit interesting.

[KerbMav]

You have my vote on this one.

Tilted Kerbin axis, equally inclined orbit for Mun to keep easy accessibility for new players and reduce eclipses.

My head has issues imagining how it would easy accessibilty of Duna though - our Mars equivalent being the most likely next target after Mun.

[Red Iron Crown]

Is this a "we haven't implemented it yet" thing or a "would require a significant rework" thing? More specifically, is axial tilt compatible with the patched conic/SOI model as implemented in KSP?

I'd like to see this implemented, too, but I don't know if it's feasible or not.

[Kasuha]

Is this a "we haven't implemented it yet" thing or a "would require a significant rework" thing? More specifically, is axial tilt compatible with the patched conic/SOI model as implemented in KSP?

I'd like to see this implemented, too, but I don't know if it's feasible or not.

As far as I understand the matter:

I think it's more of "would require substantial rework" case although I believe it's not quite as substantial as first glance might suggest.

Patched conics should not be affected, for them the planet is just massive point and rotational axis is not important

Rotational frame of reference would need to rotate along different axis, inertial frame of reference could stay ecliptic-oriented (means rework of transfer between the two)

Planet surface display would need to be adjusted (obviously)

Navball code would need to be adjusted to show correct direction in inertial frame of reference, would not need change in rotational frame

There might be some problems and reworks in evaluating direction towards Sun for solar panels.

... and probably many things I have no clue about.

Edited May 23, 2014 by Kasuha

[lajoswinkler]

This should've been added ages ago.

[MAKC]

Wholeheartedly support this suggestion.

[Seshins]

yup completley agree - axial tilt is a reality confronting IRL engineers and scientists

[LethalDose]

I support planets with axial tilt. Now that being said...

Axial tilt, while important for "realism" or "believablity" in the game, isn't a foundational mechanic to game play (Which is what I must assume "scope complete" refers to, since the devs haven't actually defined the term). Therefore, I think planets with axial should be added before launch, but after the game is "scope complete".

I think giving Kerbin itself an axial tilt is an absolutely dreadful idea. New players coming into the game will have one more difficulty launching into orbits on the ecliptic. Learning to rendezvous in LKO becomes substantially more complex unless they are launching "correctly" from the start of the mission. Interplanetary missions also become somewhat more difficult to account for as they will almost certainly not exit kerbin on the Kerbolar ecliptic. The gains to be had from Kerbin on a tilted axis with Minmus in a coplanar orbit are, IMO, much much to small to offset the steeper learning curve to new players.

I'm not disagreeing because "I don't want things to change" and I'm not disagreeing for the sake of being contrary. I just think Kerbin having an axial tilt by default is a bad idea.

If "planets with axial tilt" were an option players could select at the beginning of a game, I'd be all for it, and I'd happily check that box. But, overall, I don't think it would benefit new players at all.

[Semmel]

I think giving Kerbin itself an axial tilt is an absolutely dreadful idea. New players coming into the game will have one more difficulty launching into orbits on the ecliptic. Learning to rendezvous in LKO becomes substantially more complex unless they are launching "correctly" from the start of the mission.

Thats not true. You can still launch in the equatorial plane, which would not change compared to the current game. It would be different if KSC would not be placed on the equator, but I suspect that this will still be the case. Once in Orbit, adjusting the orbit to ecliptic plane by not thrusting exactly prograde does not cost much more dV. The difficulty is not that much harder. Than, for interplanetary transfer, it is pretty easy to adjust the orbital plane the moment you enter the SOI of a celestial body. And mind you, its not supposed to be easy!

Cheers,

Roland

[the_bT]

I like the idea.

I'm just struggling to figure out how I would launch into the uhh... ecliptic? (the plane where all the planets are). Now I launch, set mun as target and have ascending and descending nodes to burn inclination away. I should probably not be able to do that from a is-it-realistic point of view... but how would I do it?

I guess the real deal is to track some stars and do some math and then know where to go. I'm not the real deal though

Edit: on the other hand, if I go interplanetary I go to some calculator and get some inclination and angle to prograde, all that needs to change is the calculator really.

Edit2: I think I know how to do it. Know the axial tilt angle, burn over the terminator until inclination is equal, need to do it in the right direction but I can figure that out on the fly

Edited May 27, 2014 by the_bT

[Red Iron Crown]

I like the idea.

I'm just struggling to figure out how I would launch into the uhh... ecliptic? (the plane where all the planets are). Now I launch, set mun as target and have ascending and descending nodes to burn inclination away. I should probably not be able to do that from a is-it-realistic point of view... but how would I do it?

I guess the real deal is to track some stars and do some math and then know where to go. I'm not the real deal though

Instead of launching due East, you would launch slightly North or South of it, depending on the time of day.

Alternately, launch due East and adjust the inclination once in orbit. Less efficient but simpler.

[xrayfishx]

I support planets with axial tilt. Now that being said...

Axial tilt, while important for "realism" or "believablity" in the game, isn't a foundational mechanic to game play (Which is what I must assume "scope complete" refers to, since the devs haven't actually defined the term). Therefore, I think planets with axial should be added before launch, but after the game is "scope complete".

I think giving Kerbin itself an axial tilt is an absolutely dreadful idea. New players coming into the game will have one more difficulty launching into orbits on the ecliptic. Learning to rendezvous in LKO becomes substantially more complex unless they are launching "correctly" from the start of the mission. Interplanetary missions also become somewhat more difficult to account for as they will almost certainly not exit kerbin on the Kerbolar ecliptic. The gains to be had from Kerbin on a tilted axis with Minmus in a coplanar orbit are, IMO, much much to small to offset the steeper learning curve to new players.

I'm not disagreeing because "I don't want things to change" and I'm not disagreeing for the sake of being contrary. I just think Kerbin having an axial tilt by default is a bad idea.

If "planets with axial tilt" were an option players could select at the beginning of a game, I'd be all for it, and I'd happily check that box. But, overall, I don't think it would benefit new players at all.

How damn easy must we let this game become until it's good enough for new players? SQUAD can either make it easy for new players AND add options to make it harder without mods OR they should not make it any more easier and make it more interesting for more experienced players instead. If they continue easing the learning curve like they do right now, it'll end up a straight horizontal line at the bottom of the graph.

[Sirrobert]

How damn easy must we let this game become until it's good enough for new players? SQUAD can either make it easy for new players AND add options to make it harder without mods OR they should not make it any more easier and make it more interesting for more experienced players instead. If they continue easing the learning curve like they do right now, it'll end up a straight horizontal line at the bottom of the graph.

Yes, the horror.

Next we'll give them actually usefull tools to build rockets. Can you imagine?

[xrayfishx]

Yes, the horror.

Next we'll give them actually usefull tools to build rockets. Can you imagine?

The useful tools would be for the experienced, the new players wouldn't know what to do with them. However, that's a completely different subject, we're talking about axial tilt here.

Most of the time axial tilt wouldn't even make a difference, most of the game is played in LKO. If you go interplanetary often, you would get used to launching to a non-equatorial orbit. If you don't, well, it wouldn't be that difficult to take it into account for once.

It would add a lot of realism without creating huge challenges for anyone.

[Red Iron Crown]

...most of the game is played in LKO.

You and I play very different games, apparently. LKO is a brief stopover on the way to the real destination for me.

[Sirrobert]

The useful tools would be for the experienced, the new players wouldn't know what to do with them. However, that's a completely different subject, we're talking about axial tilt here.

Most of the time axial tilt wouldn't even make a difference, most of the game is played in LKO. If you go interplanetary often, you would get used to launching to a non-equatorial orbit. If you don't, well, it wouldn't be that difficult to take it into account for once.

It would add a lot of realism without creating huge challenges for anyone.

Offcourse, my bad.

We should first teach newbys how to push a nail into the wall, before explaining them how to use a hammer

[rtxoff]

I think it is a good idea for an hard/realistic mode but not default/easy mode.

[Kasuha]

I like the idea.

I'm just struggling to figure out how I would launch into the uhh... ecliptic? (the plane where all the planets are). Now I launch, set mun as target and have ascending and descending nodes to burn inclination away. I should probably not be able to do that from a is-it-realistic point of view... but how would I do it?

I guess the real deal is to track some stars and do some math and then know where to go. I'm not the real deal though

Edit: on the other hand, if I go interplanetary I go to some calculator and get some inclination and angle to prograde, all that needs to change is the calculator really.

Edit2: I think I know how to do it. Know the axial tilt angle, burn over the terminator until inclination is equal, need to do it in the right direction but I can figure that out on the fly

You set any planet (at favorable angle, preferably all the way across the system) as your target, launch when KSC is in ecliptic plane and perform gravity turn towards/away from your target.

Edited May 27, 2014 by Kasuha

[Red Iron Crown]

Wouldn't it vary by season? I thought you'd want to launch when KSC is coplanar with the ecliptic. I.e. at the solstices, you'd want to launch near sunrise/sunset; at the equinoxes you'd want to launch at noon or midnight.

Edit: You edited while I was posting, not really relevant now.

[guigui30000]

I think axial tilt would be great !

And there would be no issues for beginners. As my english is poor, here is an amazing drawing for everybody.

Edited November 12, 2020 by guigui30000
Fixed the image link

[xvdBanksbvx]

I think axial tilt would be great !

And there would be no issues for beginners. As my english is poor, here is an amazing drawing for everybody.

http://image.noelshack.com/fichiers/2014/22/1401545942-amazing-paint-skills.png

I believe a set up like this would be better for both new players and the more experienced, as it presents simple yet varied challenges they can overcome.

i.e. Launching the same as always or for the first time and going equatorial, means Minus is probably the best option unless you want to do a plane change and go to the Mun.

This would make learning the games mechanics easier for new players, because having to do things like a plane change or launching off the equator to reach another body would not take and interplanetary flight.

The quicker you can make and learn from a mistake the better.

It's also better for older players because it adds more realism and fun challenge to the existing system.

[horndgmium]

Well axial tilt is interesting and all but if the axis does not wobble all it does is change your plane of reference. Without axial wobble, you get the same result by putting the left side of your computer on a book so now up is what was originally tilted to the left.