Data initialization

Orbit

To initialize an orbit, we simply have to build it using [PATRIUS] object. For example:

final TimeScale TUC = TimeScalesFactory.getUTC();
final AbsoluteDate date = new AbsoluteDate("2010-01-01T12:00:00.000", TUC);       
final double sma = Constants.WGS84_EARTH_EQUATORIAL_RADIUS + 250.e3;
final double ecc = 0.;
final double inc = FastMath.toRadians(51.6);
final double raan = FastMath.toRadians(0.);
final double pa  = FastMath.toRadians(0.);
final double ano = FastMath.toRadians(0.);
final Frame GCRF = FramesFactory.getGCRF();
final KeplerianOrbit iniOrbit =
  new KeplerianOrbit(sma, ecc, inc, raan, pa, ano, PositionAngle.MEAN, GCRF, date, MU);

Earth features

Data equivalent to the “Earth_Features Earth features” tab are distributed via two arguments:

1. A ExtendedOneAxisEllipsoid object which will define the shape of the planet

<syntaxhighlight lang="java"> final ExtendedOneAxisEllipsoid EARTH =

  new ExtendedOneAxisEllipsoid(REQ, FLAT, ITRF, "EARTH");

<syntaxhighlight>

1. A type of enumerates that will propose some pre-defined configurations as:

• NOTHING (all options set to null)
• ONLY_PREC_NUT (only precession and nutation)
• FACTORY (equivalent to the most complete definition as in the GUI)
• IGNORE (nothing is define internally by PSIMU which will take into account the user parametrization previously done)