[1.1.3] Orbital Decay v1.5.2 (17/07/2016) - Total Overhaul

[Sir_Fanch]

@leudaimon I generally just set the root part to something either attached to vanguard or the decoupler directly below it, this way you still get the deltaV readings correct. Although that CoL issue is not one I've heard of. Sorry I couldn't be of any help man, that does sound pretty wrong though, I didn't have any huge issues aside from the mechjeb windows with those mods, good luck though

[FennexFox]

Will this mod work well with Principia? I know that Principia aims to implement orbital decay but not yet, isn't it?

[Whitecat106]

8 hours ago, FennexFox said:

Will this mod work well with Principia? I know that Principia aims to implement orbital decay but not yet, isn't it?

Hello there!

Honestly I have not tried the two, but since KSP has a limited number of orbit changing functions I would assume this would be compatible for now. However in the 1.6.0 release of Orbital Decay, the two will not be compatible; with Principia effectively doing very similar things but in a somewhat more complex way!

 

As for 1.6.0 progress,

Although slow, I have been working on the NBody version, having some big problems so far but the framework is in place, hopefully once I can manage to accurately build the eccentricity, longitude of ascending node, argument of periapsis and mean anomaly from state vectors I will have working version. Of course I am having to do a great deal of simplification to bust lag (especially during timewarp), in the meantime however, if progress is still show by this time next week, I shall release 1.5.2 for KSP 1.1.3, this will include some FPS improvements for the UI, some UI filtering and afew more additions I was saving for the 1.6.0.

If anyone has any experience in State vector orbital representation or more important the conversion factors for the different position/ coordinate systems in KSP please get in touch!

At the moment the two body problem is pretty much solved, but the 3 body and thus n body problem still requires alot of work. As for new conics.... well that should fall into place once I can generate the orbit predictions accurately.. - Matlab would be pretty useful right now!

I am leaving the body perturbations until last (so as to not further complicate the nbody simulator!)

So in short, 1.5.2 for KSP 1.1.3 next week if I get really bogged down with this! If not hopefully some breakthroughs will speed things up!

Whitecat106

 

[autumnalequinox]

10 hours ago, Whitecat106 said:

Hello there!

...

So in short, 1.5.2 for KSP 1.1.3 next week if I get really bogged down with this! If not hopefully some breakthroughs will speed things up!

Whitecat106

 

Yay!  I'm going to hold out on my first try of Realism Overhaul until then.  I think this will be a great addition to it.

[Sotakarhu]

Lingering issues aside, does this mod work well with a mostly stock KSP? Or is it best when using RO/RSS/etc.? I'm going to be doing a historical campaign with mostly all stock parts, and a just a few mods to make it more challenging/interesting like life support, remote tech, construction time, and orbital decay if it will work well. 

[autumnalequinox]

3 hours ago, Sotakarhu said:

Lingering issues aside, does this mod work well with a mostly stock KSP? Or is it best when using RO/RSS/etc.? I'm going to be doing a historical campaign with mostly all stock parts, and a just a few mods to make it more challenging/interesting like life support, remote tech, construction time, and orbital decay if it will work well. 

I used it in a "stock enhanced" game.  Everything scaled as stock with alot of "add-on" mods.  RSS/RO isn't required.

[Whitecat106]

Hello everyone,

Just put out a 1.5.2 which is a recompile for KSP 1.1.3, contains some small bug fixes and a UI filtering option, this is pretty much a mash up of some features of 1.6.0 but released early! As for the new main version release, hopefully I will be able to release N-Body decay by the end of the month... progress still slow I also have to shift some attention to Historic Missions for the new Contract Configurator update, but I will be working on the mod for a few hours this evening to see what I can do!

At the moment the main issue is with Timewarp, for stock this is not much of a problem due to the timewarp limits, however in RSS the timewarp rate is much greater, so the sample time for NBody predictions has to be either increased...or more accurate, whilst keeping FPS above 50; not an easy task, but things are starting to fall together so fingers crossed everything will work out!

Whitecat106

[ebigunso]

Hello. I see that the default decay multiplier is set to 10. Should I keep it this way for RSS games, or should I turn it down to 1?

[Sol Invictus]

I'd like to know that as well. Also, what does setting "RealisticDecay" as True in Settings.cfg change exactly?

[Whitecat106]

@ebigunso sorry about this. Looks like a setting I changed accidentally then redistributed for both stock and Rss; I would recommend setting this to 1 instead of 10 - otherwise orbits will decay 10x faster! 

@Sol Invictus

This setting is depreciated and should have no effect to gameplay, it was added pre 1.2.0 as an option to allow realistic decay instead of the former stock model (which no longer is implemented and only applied to atmospheric drag), the only decay formula used now is one based on actual decay equations as of 1.3.0 +!  

 

As for some other 1.5.2 things, the NBody simulation breakdown tab currently has no practical use as NBody simulation is not yet added, this simply shows a (possibly incorrect) display of velocity perturbations acting on the vessel per second (UT). Also the icons seem slightly misfitted, - the closest I could find from the Stock folder! I will find some more fitting for 1.5.3! 

 

Another plaguing issue is the quickload vessel orbit update issue, e.g quicksaving before a moon landing, crashing accidentally and reloading causing the vessel to reload at a position closer to the moon not equal to the quicksave position can be a pest, but can be remedied by deleting the cfg entry for the vessel in the VesselData.cfg file prior to quickloading. This will reload the vessel at the correct position at the time of the quicksave! This will be fixed in 1.5.3! 

 

As for 1.6.0; NBody is a real pain, in theory the process should be simple but I think afew days off and a complete NBody rewrite is in order to sort things out! In the meantime I will reduce the Github issue list and bring out a 1.5.3 with fixes for the issues above, some more mascon and yarkovsky fixes and a lifting of the atmosphere decay height limit (currently at 1000Km) so expect your small light geostationary satellites to decay in about 700 years! 

 

I will also be taking some time off to further develop the SCS plugin and work on a new mod I have had in the pipeline for afew months, and hopefully a revamp of my maritime missions contract pack since @Fengist has returned! 

Whitecat106  

[M4ssler]

Good morning. 

Can i use this mod with outer planets?

 

[Whitecat106]

Hello there @M4ssler, I believe everything should work fine with Outer Planets, decay might be quite high around Sarnus for example, but everything should work.  

[ebigunso]

I found the notifications for when a satellite has decayed is a little too subtle, being shown on screen for only brief moments.

If you could make it so that notifications pop up in the notifications tab of the game, that would certainly help.

[Whitecat106]

1 hour ago, ebigunso said:

I found the notifications for when a satellite has decayed is a little too subtle, being shown on screen for only brief moments.

If you could make it so that notifications pop up in the notifications tab of the game, that would certainly help.

Good idea! I have noticed this myself actually, added to the 1.5.3 list

[SyzygyΣE]

Good day everyone. I have two issues to report on the mod in my RSS/RO career.

I have a rather bizarre problem with the mechanics of decay over time. I launched a small satellite to LEO—about 250km altitude. However, while the Orbital Decay window seems to suggest that the orbit will decay, and indeed it does update over a period of time regarding time until decay, decay rate and other information, the orbit itself does not change at all. The Player.log doesn't show any exceptions or abnormality regarding the mod. And I have to say, everything but the actual changes in orbit height function pretty well. I get the feeling it may have to do with the tracking station not yet updated and hence patched conics not available, but I don't know. Would you like me to acquire the Player.log file regardless?

The second issue is that when I click on "Toggle Decay Rate Breakdown," a window showing the following line appears:

WARNING: Error detected, this is a MasCon issue.

It also asks me to put down the vessel latitude/longitude on the forums and inform you. But quite frankly that window appears no matter what orbit I'm in. Any latitude or longitude will result in its appearance. What does it mean?

I have attached a screenshot here of the Orbital Decay window.

Edited July 28, 2016 by SyzygyΣE

[baldamundo]

What's the performance footprint of this mod like these days?

[h0yer]

On 29.7.2016 at 5:50 PM, baldamundo said:

What's the performance footprint of this mod like these days?

Minimal, if you don't let accumulate too much debris in your LEO/LKO, all of it (fairings / uppers tages @ orbital velocities) should decay nicely without taking too much CPU. And if it is decayed, no more calculations

 

OK, I actually wanted to just thank the author of this great mod, for this great mod

 

And I wanted to report a few 'quirks' I noticed while extensively enjoying this mod, before it just stopped decaying stuff^^

It happened all of a sudden, decay calculations are still going, even station keeping fuel is calculated, no errors, no mascon stuff, things just stay where they were put, no decay, as if it was deactivated, while I had the decay difficulty at 0.8 the last time. Resources are not consumed as well.

Beforehand, I manually deleted a few debris parts (save editor) which have been decayed into negative altitudes by the last version (fixed in the current)

The next thing I did, rendezvouz of two identical manned vehicles, both had their station keeping enabled, and as soon as both docked, ghost forces were applying, AP value was 'locked' and the orbit became more and more 'funky'. (Never reached AP, passed below AP, orbit became suborbital, then normal again, vertical velocity seemed to be 'frozen' as well. Weird stuff^^)

I reverted the flight and continued doing 'the other things' and noticed that OD somehow stopped decaying stuff. Then I removed it temporarily, waiting until 'something' happens.

If you need logs, I'll upload them after work...

 

Have fun

[Sir_Fanch]

On 28/07/2016 at 7:35 PM, SyzygyΣE said:

the orbit itself does not change at all

 

1 hour ago, h0yer said:

before it just stopped decaying stuff

1.1.3 added an option to stock KSP to 'freeze' orbits (to stop the orbit wobble bug), it's activated by default and needs to be de-activated for Orbital Decay to work AFAIK. I'm not 100% on the name or location of the option but it's in the options of the main menu. Sorry if this doesn't help, both of those sound like problems with that though just from a quick glance and I thought there might be a small chance you could fix your games quickly .

[SyzygyΣE]

19 minutes ago, Sir_Fanch said:

1.1.3 added an option to stock KSP to 'freeze' orbits (to stop the orbit wobble bug), it's activated by default and needs to be de-activated for Orbital Decay to work AFAIK. I'm not 100% on the name or location of the option but it's in the options of the main menu. Sorry if this doesn't help, both of those sound like problems with that though just from a quick glance and I thought there might be a small chance you could fix your games quickly .

Oh, yes. Now I recall that was indeed added. I haven't tested turning that off yet. It should be in the settings somewhere. I shall test turning it off and report back.

Edited August 1, 2016 by SyzygyΣE

[Sir_Fanch]

Hope I could help 

[h0yer]

6 hours ago, Sir_Fanch said:

Hope I could help 

Unh, now I feel stupid

Never knew of this setting, will give it another try, thanks for pointing out

 

EDIT:

OMG it works!

Thanks for the hint

Edited August 1, 2016 by h0yer
Reporting back...

[ebigunso]

20 hours ago, h0yer said:

Unh, now I feel stupid

Never knew of this setting, will give it another try, thanks for pointing out

 

EDIT:

OMG it works!

Thanks for the hint

Probably many like you don't notice there is such a setting, so I suggest @Whitecat106 to add a notice to the OP so everyone can enjoy this Mod's full potentials.

Heck, I didn't notice this either

EDIT: It's the "Orbital Drift Compensation" option in the settings right?

Edited August 2, 2016 by ebigunso

[Whitecat106]

Hello everyone,

Thanks for reminding me about the Orbital Drift Compensation setting, completely forgot about it when I put out 1.5.2! I knew there was something else I had to include for the update! Anyway for now I shall leave the solution next to the download button on the first page, everything abit too messy at the moment for a 1.5.3, but 1.6.0 is coming.

So far 1.6.0 features include:

- NBody Simulation: will be completed for the next merge on Github, this may result in some lag at high timewarp but hopefully I have found a solution to cut down lag by reducing orbit simulation samples (at the cost of some accuracy) during exceptionally high timewarp (so the biggest issue will be full timewarp in an RSS-RO game). This NBody perturbation will only effect vessels that are a sufficient distance away from a planet,- purely for the sake of performance at the moment, e.g a small wiggle in a closely orbiting space station isnt really worth 1/2 a FPS, whereas a vessel with an eccentric orbit beyond the hill sphere of a moon of the Jupiter system is much more interesting and worth while; that being said the true performance impact will become apparent when I release a 1.6.0 testing version for everyone to try out and give some feedback! Station keeping will prevent n body perturbations, but will require a lot more fuel - pretty essential for rendezvous. 

- NBody conics, the code is pretty much there in the most recent Github update, the maths and the logic works... but for some reason the lines are a squiggly mess in the corner of the tracking station... this should surely be the easy bit... not to worry! This is my main goal at the moment, since the code for predicting the vessel positions used to generate the orbital path lines is pretty much identical to the actual vessel perturbation code. - When one works the other should too and with a visible path I can better check that everything is predicting correctly. The biggest issue at the moment is just putting things in the right type of coordinates (WorldSpace, ScaledSpace, RelativePositions and World Positions etc).

- VAB-SPH UI: Contains information on your vessel, how long it would take to decay and how much station keeping fuel would be required for a duration etc etc - Plan your missions easier! - 50% complete, just need to add station keeping info etc.

- Quick Load fixes: Stops that annoying bug I mentioned a few posts back!

- User alerts: More visible, better timed alerts about when a vessel is running out of fuel, about to decay and has decayed. Maybe an alert for 50% station keeping fuel remaining?

- Automatic force disabling of the Orbital Drift Compensation setting.

- Map overlays for Hill Spheres and SOI's, (nice togglable circular lines around bodies so you can visually see intersections (needs the NBody conics to draw lines correctly first!).

 

You can check out progress at the github, any assistance would be appreciated, especially with the conics drawing in the MapView. Its been a while working all of this out but I think everything is finally coming together abit more. I will not put up a .dll yet since the NBody perturbation equations need yet another rebuild (See Github issue #77 comments), so at the moment timewarp can cause the orbit to break entirely. Once conics are fixed I will rebuild the NBody code (pretty quick fix actually) and release a test .dll for everyone to try out the new features. Again, NBody will be completely optional because I know how much more complicated it can make interplanetary transfers etc...

Any more issues that anyone can find, please let me know and I will add them to the 1.6.0 list.

Whitecat106

[M4ssler]

Hello @all,

is there any guide how to use it. the button for enable station keeping i found ;-)

But what does toggle nobdy breakdown and toggle decay rate breakdown. My english is  not the best and the translator gives nothing unseful translation

[SyzygyΣE]

As had been suggested before, I turned off Orbital Drift Compensation to try and allow the mod to work through a manual process but the issue I've had has kept recurring: the UI says the orbit will decay after some time, but the orbit height never changes from orbit to orbit.

I think I might wait for 1.6.0 and then report back my findings. It certainly is bizarre that it worked for @h0yer but not myself. I will keep progressing through my career and see how I go.

I can't spot anything unusual about orbital decay in the Player.log but I'll see if I can get a link here to one anyway so you guys can have a look.

@h0yer, you are playing with Stock, correct? I'm thinking that fact that I have RSS might be the problem but I really don't know. Nonetheless, I'll acquire a copy of my log tomorrow.

Edited August 2, 2016 by SyzygyΣE