EcksteinHechlerOrbitalState.java
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package org.orekit.propagation.conversion.averaging;
import org.orekit.forces.gravity.potential.UnnormalizedSphericalHarmonicsProvider;
import org.orekit.frames.Frame;
import org.orekit.orbits.CircularOrbit;
import org.orekit.orbits.Orbit;
import org.orekit.orbits.OrbitType;
import org.orekit.orbits.PositionAngleType;
import org.orekit.propagation.PropagationType;
import org.orekit.propagation.analytical.EcksteinHechlerPropagator;
import org.orekit.time.AbsoluteDate;
import org.orekit.propagation.conversion.averaging.elements.AveragedCircularWithMeanAngle;
/**
* Class representing an averaged orbital state as in the Eckstein-Hechler theory.
*
* @author Romain Serra
* @see AveragedOrbitalState
* @see EcksteinHechlerPropagator
* @since 12.1
*/
public class EcksteinHechlerOrbitalState extends AbstractHarmonicsBasedOrbitalState {
/** Averaged circular elements. */
private final AveragedCircularWithMeanAngle averagedElements;
/**
* Constructor.
* @param date epoch
* @param elements averaged orbital elements
* @param frame reference frame
* @param harmonicsProvider spherical harmonics provider
*/
public EcksteinHechlerOrbitalState(final AbsoluteDate date,
final AveragedCircularWithMeanAngle elements,
final Frame frame,
final UnnormalizedSphericalHarmonicsProvider harmonicsProvider) {
super(date, frame, harmonicsProvider);
this.averagedElements = elements;
}
/** {@inheritDoc} */
@Override
public OrbitType getOrbitType() {
return OrbitType.CIRCULAR;
}
/** {@inheritDoc} */
@Override
public PositionAngleType getPositionAngleType() {
return PositionAngleType.MEAN;
}
/** {@inheritDoc} */
@Override
public AveragedCircularWithMeanAngle getAveragedElements() {
return averagedElements;
}
/** {@inheritDoc} */
@Override
public Orbit toOsculatingOrbit() {
final EcksteinHechlerPropagator propagator = createPropagator();
return propagator.propagateOrbit(getDate());
}
/**
* Create Eckstein-Hechler propagator.
* @return propagator using relevant theory
*/
private EcksteinHechlerPropagator createPropagator() {
final CircularOrbit orekitOrbit = createOrekitOrbit();
return new EcksteinHechlerPropagator(orekitOrbit, getHarmonicsProvider(),
PropagationType.MEAN);
}
/**
* Create circular orbit representation of averaged state.
* @return circular orbit
*/
private CircularOrbit createOrekitOrbit() {
return new CircularOrbit(averagedElements.getAveragedSemiMajorAxis(),
averagedElements.getAveragedCircularEx(), averagedElements.getAveragedCircularEy(),
averagedElements.getAveragedInclination(),
averagedElements.getAveragedRightAscensionOfTheAscendingNode(),
averagedElements.getAveragedMeanLatitudeArgument(), getPositionAngleType(),
getFrame(), getDate(), getMu());
}
}