Principia causing unnatural orbit

[rattata21216]

I'm trying to create some Kopernicus and Principia configs to make the stock system match the real solar system.
I have been mostly successful outside of Gilly. I moved it into a low orbit around Duna to represent Phobos. But for some reason, every time I open a save, it immediately starts slowing down and enters this orbit that makes it repeatedly fall under the surface. The only large body nearby is Duna. 

This is the Kopernicus config for Gilly:
 

@Kopernicus:FOR[RealisticStockSystem]
{
  %Body[Gilly]
  {
    %Orbit
    {
      %referenceBody = Duna
      semiMajorAxis = 885000
      eccentricity = 0.05
      inclination = 0.8
    }
  }
}

Does anyone know what causes this and/or how to fix it?

[Leganeski]

Hello and welcome to the forums, @rattata21216!

5 hours ago, rattata21216 said:

      semiMajorAxis = 885000
      eccentricity = 0.05
      inclination = 0.8

 

These lines need "%" or "@" at the start. Without that, they're giving Gilly new orbital parameters in addition to its usual parameters, rather than replacing them. I'm not completely sure whether this is causing the problem, but my guess is that Principia is somehow mixing up the old and new parameters, resulting in weird orbits such as the one you encountered.

[RevanX_LSR]

Also if you are doing this in real solar system scale, 885km is very low for a Phobos orbit. even below the surface of Duna. (if it was built to represent mars)

6 hours ago, Leganeski said:

Hello and welcome to the forums, @rattata21216!

These lines need "%" or "@" at the start. Without that, they're giving Gilly new orbital parameters in addition to its usual parameters, rather than replacing them. I'm not completely sure whether this is causing the problem, but my guess is that Principia is somehow mixing up the old and new parameters, resulting in weird orbits such as the one you encountered.

It’s also possibly a problem with floating point accuracy when dealing with fast orbits, a bit like what you get on Lili.

[rattata21216]

On 8/11/2023 at 9:38 PM, Leganeski said:

Hello and welcome to the forums, @rattata21216!

These lines need "%" or "@" at the start. Without that, they're giving Gilly new orbital parameters in addition to its usual parameters, rather than replacing them. I'm not completely sure whether this is causing the problem, but my guess is that Principia is somehow mixing up the old and new parameters, resulting in weird orbits such as the one you encountered.

Thank you for the reply! Unfortunately it would appear that this is likely a bug with Principia and not from the config file, as I've added a % in front of each line (as well as made it load before Principia) and it is still happening. 
This is the most recent config file for Gilly:
 

@Kopernicus:FOR[RealisticStockSystem]:BEFORE[Principia]
{
  %Body[Gilly]
  {
    %Orbit
    {
      %referenceBody = Duna
      %semiMajorAxis = 885000
      %eccentricity = 0.05
      %inclination = 0.8
    }
  }
}

I think the bug is related to Gilly somehow being too close to Duna, as I have Hale (from the Outer Planets Mod) orbiting farther away as Deimos and I have never experienced the same issue with that (or any other moon). For now I think I'll just try moving it to a farther orbit

[RevanX_LSR]

On 8/12/2023 at 4:08 PM, RevanX_LSR said:

Also if you are doing this in real solar system scale, 885km is very low for a Phobos orbit. even below the surface of Duna. (if it was built to represent mars)

It’s also possibly a problem with floating point accuracy when dealing with fast orbits, a bit like what you get on Lili.

 

On 8/13/2023 at 10:50 PM, rattata21216 said:

Thank you for the reply! Unfortunately it would appear that this is likely a bug with Principia and not from the config file, as I've added a % in front of each line (as well as made it load before Principia) and it is still happening. 
This is the most recent config file for Gilly:
 

@Kopernicus:FOR[RealisticStockSystem]:BEFORE[Principia]
{
  %Body[Gilly]
  {
    %Orbit
    {
      %referenceBody = Duna
      %semiMajorAxis = 885000
      %eccentricity = 0.05
      %inclination = 0.8
    }
  }
}

I think the bug is related to Gilly somehow being too close to Duna, as I have Hale (from the Outer Planets Mod) orbiting farther away as Deimos and I have never experienced the same issue with that (or any other moon). For now I think I'll just try moving it to a farther orbit

Yeah. GPP lili has some problems, it also orbits barely above the surface of a huge super earth.