Class GLONASSNumericalPropagator

  • All Implemented Interfaces:
    Propagator, PVCoordinatesProvider

    public class GLONASSNumericalPropagator
    extends AbstractIntegratedPropagator
    This class propagates GLONASS orbits using numerical integration.

    As recommended by the GLONASS Interface Control Document (ICD), a 4th order Runge-Kutta technique shall be used to integrate the equations.

    Classical used of this orbit propagator is to compute GLONASS satellite coordinates from the navigation message.

    If the projections of luni-solar accelerations to axes of Greenwich geocentric coordinates X''(tb), Y''(tb) and Z''(tb) are available in the navigation message; a transformation is performed to convert these accelerations into the correct coordinate system. In the case where they are not available into the navigation message, these accelerations are computed.

    Caution: The Glonass numerical propagator can only be used with GLONASSNavigationMessage. Using this propagator with a GLONASSAlmanac is prone to error.

    Author:
    Bryan Cazabonne
    See Also:
    GLONASS Interface Control Document
    • Constructor Detail

      • GLONASSNumericalPropagator

        public GLONASSNumericalPropagator​(ClassicalRungeKuttaIntegrator integrator,
                                          GLONASSOrbitalElements glonassOrbit,
                                          Frame eci,
                                          AttitudeProvider provider,
                                          double mass,
                                          DataContext context,
                                          boolean isAccAvailable)
        Private constructor.
        Parameters:
        integrator - Runge-Kutta integrator
        glonassOrbit - Glonass orbital elements
        eci - Earth Centered Inertial frame
        provider - Attitude provider
        mass - Satellite mass (kg)
        context - Data context
        isAccAvailable - true if the acceleration is transmitted within the navigation message
    • Method Detail

      • getGLONASSOrbitalElements

        public GLONASSOrbitalElements getGLONASSOrbitalElements()
        Gets the underlying GLONASS orbital elements.
        Returns:
        the underlying GLONASS orbital elements
      • propagate

        public SpacecraftState propagate​(AbsoluteDate date)
        Propagate towards a target date.

        Simple propagators use only the target date as the specification for computing the propagated state. More feature rich propagators can consider other information and provide different operating modes or G-stop facilities to stop at pinpointed events occurrences. In these cases, the target date is only a hint, not a mandatory objective.

        Specified by:
        propagate in interface Propagator
        Overrides:
        propagate in class AbstractIntegratedPropagator
        Parameters:
        date - target date towards which orbit state should be propagated
        Returns:
        propagated state
      • createMapper

        protected StateMapper createMapper​(AbsoluteDate referenceDate,
                                           double mu,
                                           OrbitType orbitType,
                                           PositionAngleType positionAngleType,
                                           AttitudeProvider attitudeProvider,
                                           Frame frame)
        Description copied from class: AbstractIntegratedPropagator
        Create a mapper between raw double components and spacecraft state. /** Simple constructor.

        The position parameter type is meaningful only if propagation orbit type support it. As an example, it is not meaningful for propagation in Cartesian parameters.

        Specified by:
        createMapper in class AbstractIntegratedPropagator
        Parameters:
        referenceDate - reference date
        mu - central attraction coefficient (m³/s²)
        orbitType - orbit type to use for mapping
        positionAngleType - angle type to use for propagation
        attitudeProvider - attitude provider
        frame - inertial frame
        Returns:
        new mapper