Whitecat106

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

Recommended Posts

KSP Orbital Decay Full Version (v1.5.0)

 

Introduction

Hello everyone, Whitecat106 here creator of the Historic Missions Contract Pack and I wish to share with you the release version of my new project. I have been working on this for quite a while and can now release this mod after I finally had a break through in the code - as a result of months of tinkering! Some mods in the past have come so close to this but none actually produced a viable working version... well until now...

What does it do?

  • On rails and off rails orbital decay for any vessel around any celestial body, this decay is determined by various factors, such as atmospheric drag, radiation pressure drag and more!
  • Estimated impact times are given for each vessel.
  • Station Keeping for active and non active vessels. Supports all KSP Resources.
  • UI interface for predicted decay times and vessel information.
  • The above work during time-warp!

This is the full release version of the in-development mod featured here.

 

Initial Dev Video:

https://www.youtube.com/watch?v=CoeHIbgr-wo

* Note this video shows the V0.0.1 Dev version, the features of this Release version differ slightly.

 

Notes:

For information on how to use the mod check out the wiki below!

Orbital Decay Wiki :             | Wiki |

 

Known Incompatibilities: (Major, Minor)

- RSS Extrasolar - Sagitarius A* causes problems with the coding of the mod, use at your own risk. Similarly other 'galactic core mods' may cause problems - To be fixed in 1.6.0

- Mechjeb autopilot can fail when nearly reaching a set altitude due to drag reducing the actual altitude - Fix in 1.6.0, other autopilot mods may be effected.

 

Download:

SpaceDock:       | Download |  

-- Please Backup Your Saves, this is a work in progress!  PLEASE NOTE: You must disable the  ORBIT_DRIFT_COMPENSATION = True  In the KSP settings.cfg file otherwise orbits will no longer decay as of KSP 1.1.3, a fix for this on the way! Just change 'True' to 'False'

 

Github:                  |  Source |

 

Want to help a student and part time modder out?

Please consider Donating ! Any donations will be greatly appreciated!

 

Special Thanks:

- Zajc3w for the complete reworking of the station keeping / resource system!

- Everyone who has provided encouragement and has helped find bugs and report them!

 

License:

This code is licensed under the Attribution-NonCommercial-ShareAlike 3.0 (CC BY-NC-SA 3.0) creative commons license.

Enjoy! Whitecat106 :D


Edited by Whitecat106
Update - Fixes

Share this post


Link to post
Share on other sites

That's going straight into my GameData! Good job.

Wow, this is the first time I'm a first commenter. Yay!

Share this post


Link to post
Share on other sites

It's funny today I though about why nobody ever got the idea of making an orbital decay mod and that If had any skill in programming I would.

Well there you are, I bet the idea bugged you from the start when working on RL space station contracts wich count on orbital decay to determine launch windows and craft designs. Another great hit for more realism in KSP!

Thanks, will test it right away.

Edited by Comatorium420

Share this post


Link to post
Share on other sites

Congrats on the release! Watch this mod like a hawk, but I be one of them there remote tech users and I would be just so sad to see my nicely placed sat system come crashing back into Kerbin :o. Thanks for making such a wonderful feature in such a simple package

Share this post


Link to post
Share on other sites
Congrats on the release! Watch this mod like a hawk, but I be one of them there remote tech users and I would be just so sad to see my nicely placed sat system come crashing back into Kerbin :o. Thanks for making such a wonderful feature in such a simple package

Rejoice! you will now have to update your network every month!! Or do as I do, I got 6 Kerbin surface outposts with 6 crews with the super long range antenna and the RGU that turns it into a tracking station, 4 on the equator and 2 at the poles.

In RL they call it the deep space network and they use all of the tracking dishes from all around the world although in RL we dont need to drill for substrate in the ground to get food :P

P.S.: why the hell did you remove your 0.90 install in the first place :P

Edited by Comatorium420

Share this post


Link to post
Share on other sites

Thanks everyone! Let me know how it goes! I might need to up some decay times in the future to make it more Kerbal! :)

Congrats on the release! Watch this mod like a hawk, but I be one of them there remote tech users and I would be just so sad to see my nicely placed sat system come crashing back into Kerbin :o. Thanks for making such a wonderful feature in such a simple package

Ahh not to worry, the Dev version in the Development thread is soon to incorporate Station Keeping, keeping remote tech safe (if you have a stash of MonoPropellant that is!), on release of the Dev version the drift that satellites experience in KSP ; throwing off those once precisely positioned geosynchronous remote tech antennas, will be eliminated too!

Enjoy!

Share this post


Link to post
Share on other sites

Congrats, it's been a while to hear something from your mod.

Share this post


Link to post
Share on other sites
I would love to see a 'debris only' version of this ;)

Well, this is the core only... debris will deorbit too. But the full version will gonna have a stationkeeping function, but it requires fuel, like in real life

Share this post


Link to post
Share on other sites

Yay, now this adds some extra flavor with keeping up with my stations and communication satellite system :D

Share this post


Link to post
Share on other sites

Congratulations, Good Job! plz Expand this mod

Share this post


Link to post
Share on other sites

This looks promising! How does it deal with orbital rendezvous and interplanetary transfer? I'd hate to lose a Dres encounter during the long journey from LKO.

Share this post


Link to post
Share on other sites
Mitchz95 said:
This looks promising! How does it deal with orbital rendezvous and interplanetary transfer? I'd hate to lose a Dres encounter during the long journey from LKO.

The decay rate rapidly decreases the further from a planet you travel, so from a really low Kerbin orbit to Dres (literally less 75km) could cause some minor perturbations (you may need say 5m/s extra) to reach Kerbin escape velocity, but once you reach the orbit of the Mun the 'drag' from Kerbin falls to a very very small value until it stops (at 10x the planetary diameter distance (currently)) so the very worse case scenario would be a tiny RCS burn after leaving Kerbins SOI. There is currently no drag or decay around Kerbol so interplanetary space is the same as the stock game to traverse. Since Dres has no atmosphere and moderately low gravity, drag around Dres is low and it could take many in game months or even years before a satellite decayed.

The biggest issue I can foresee would be a really low orbit around Jool, at this point the rate of decay may be many meters per second at perihelion so an escape may be hindered, however this provides some minor benefits for aerobraking without the heat of the atmospheric friction.

Thanks for all the comments everyone, I appreciate the support!

If anyone would like to help out with development a GitHub port is available HERE. The main brickwall I have run into recently has been resource handling (one of the only things holding back the full release version), and my own messy code! But I would appreciate any help to speed things up :)

Whitecat106,

Edited by Whitecat106

Share this post


Link to post
Share on other sites

Great mod idea! Is this universal enough to work with Realism Overhaul or an alternate Kerbol system, or is it coded specifically for Kerbin/Duna/etc?

Share this post


Link to post
Share on other sites
Great mod idea! Is this universal enough to work with Realism Overhaul or an alternate Kerbol system, or is it coded specifically for Kerbin/Duna/etc?

There is nothing in the code that is body title determinate - only the body characteristics and the decay formula itself works according to real life decay , so it should not break with any scale mods, if you try it out and experience any problems or lots of NullReferenceExceptions in the Alt-F12 menu please let me know and I will look into it since I know that this mod would fit well with Realism Overhaul.

In other news progress in the Dev thread is steady, station keeping is coming!

Enjoy! :)

Whitecat

Share this post


Link to post
Share on other sites

Can you add a config file to this lite version?

Because i know that the orbits decay 10x faster than in real life, but i want to turn it down to the same value as in real life.

Because losing 3km of altitude in a 300Km orbit per orbit.... is way, way, waay to fast.

Share this post


Link to post
Share on other sites
Can you add a config file to this lite version?

Because i know that the orbits decay 10x faster than in real life, but i want to turn it down to the same value as in real life.

Because losing 3km of altitude in a 300Km orbit per orbit.... is way, way, waay to fast.

I had not planned on adding a config file but I will make some changes based on this information, I assume this was for an active vessel? e.g a vessel that you are controlling?

You see the issue is that an active vessel experiences a small drag force whereas a background vessel has its Semi Major Axis decreased by a small amount, of course these are completely different translations so trying to get the values for each equal to eachother and the planned 2km/month is difficult.

In this case if this was an active vessel I will adjust the hard coding of the active formula to a more suitable value. So I will update this mod after I have calculated the new value. Sorry for the super decay!

Share this post


Link to post
Share on other sites
I had not planned on adding a config file but I will make some changes based on this information, I assume this was for an active vessel? e.g a vessel that you are controlling?

You see the issue is that an active vessel experiences a small drag force whereas a background vessel has its Semi Major Axis decreased by a small amount, of course these are completely different translations so trying to get the values for each equal to eachother and the planned 2km/month is difficult.

In this case if this was an active vessel I will adjust the hard coding of the active formula to a more suitable value. So I will update this mod after I have calculated the new value. Sorry for the super decay!

No, it's a general decay setting: as 10 is default and 1 is "real life".

Share this post


Link to post
Share on other sites
No, it's a general decay setting: as 10 is default and 1 is "real life".

I'm sorry I don't understand what you mean, are you talking about the Dev version or this Lite version?

Share this post


Link to post
Share on other sites
I'm sorry I don't understand what you mean, are you talking about the Dev version or this Lite version?

Just the lite version.

Share this post


Link to post
Share on other sites
Just the lite version.

I have tried to repeat the issue but I cannot, for me a vessel in a circular Kerbin Orbit at 300km with a velocity of 1980.9m/s experiences a decay rate of around 3.5603x10^-5m SemiMajorAxis size per second, so therefore a decay per orbit of around 0.129 meters, not 3 kilometers :huh: Can you recreate this issue?

Was this first produced by hyperediting the vessel into a 300km orbit? Sometimes a vessel will not gain the correct orbit values if gravity is hacked in the alt-f12 menu causing the velocity to be much lower even though the vessel has a 300km orbit, this could cause issues... But apart for that I cannot see what is happening here. Unless you were maybe orbiting Jool at 300km?

Share this post


Link to post
Share on other sites
I have tried to repeat the issue but I cannot, for me a vessel in a circular Kerbin Orbit at 300km with a velocity of 1980.9m/s experiences a decay rate of around 3.5603x10^-5m SemiMajorAxis size per second, so therefore a decay per orbit of around 0.129 meters, not 3 kilometers :huh: Can you recreate this issue?

Was this first produced by hyperediting the vessel into a 300km orbit? Sometimes a vessel will not gain the correct orbit values if gravity is hacked in the alt-f12 menu causing the velocity to be much lower even though the vessel has a 300km orbit, this could cause issues... But apart for that I cannot see what is happening here. Unless you were maybe orbiting Jool at 300km?

I think it was just ksp doing weird stuff again because it didn't do it again.

But instead i found a bug in the pre-release version: if you dock two craft that has station keeping enabled on both of the crafts, your craft's orbit will suddenly keep increasing even when you disable and re-enable station keeping.

Also: the mod doesn't work on saves that have started without it.

Edited by MK3424

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.