fr.cnes.sirius.patrius.stela.forces.drag

Class StelaAtmosphericDrag

java.lang.Object

fr.cnes.sirius.patrius.stela.forces.AbstractStelaGaussContribution

fr.cnes.sirius.patrius.stela.forces.drag.StelaAtmosphericDrag

All Implemented Interfaces:

StelaForceModel, Serializable

public class StelaAtmosphericDrag
extends AbstractStelaGaussContribution

Class representing the atmospheric drag for the Stela GTO extrapolator.

Since:

1.3

Version:

$Id$

Author:

Tiziana Sabatini

See Also:

StelaAeroModel, Serialized Form

Concurrency :

not thread-safe

Concurrency comment :

not thread-safe due to use of mutable attributes

Field Summary

Fields inherited from class fr.cnes.sirius.patrius.stela.forces.AbstractStelaGaussContribution

dPert

Constructor Summary

Constructors

Constructor and Description
StelaAtmosphericDrag(DragSensitive inSpacecraft, Atmosphere inAtmosphere, int inSquaringPoints, double inEarthRadius, double inAtmoThreshold, int inDragRecomputeStep) Constructor.
StelaAtmosphericDrag(DragSensitive inSpacecraft, Atmosphere inAtmosphere, int inSquaringPoints, double inEarthRadius, double inAtmoThreshold, int inDragRecomputeStep, int orderFS) Constructor.

Method Summary

Modifier and Type	Method and Description
protected double[]	computeAnomalyBounds(double a, double e, double za) Computes true anomaly and eccentric anomaly bounds.
double[][]	computePartialDerivatives(StelaEquinoctialOrbit orbit) Compute the partial derivatives for a given spacecraft state.
double[]	computePerturbation(StelaEquinoctialOrbit orbit, OrbitNatureConverter converter) Compute the dE/dt force derivatives for a given spacecraft state.
double[]	computeShortPeriods(StelaEquinoctialOrbit orbit, OrbitNatureConverter converter) Compute the short periodic variations for a given spacecraft state.
int	getDragRecomputeStep()
void	setTransMatComputationFlag(boolean transMatrixFlag) Setter for the switch indicating whether the drag term of the transition matrix has to be computed.

Methods inherited from class fr.cnes.sirius.patrius.stela.forces.AbstractStelaGaussContribution

computeCoeffs, computeGaussDerivativeEquations, computeGaussEquations, computeQuadElements, evaluateFS, getdPert, getType

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

StelaAtmosphericDrag

public StelaAtmosphericDrag(DragSensitive inSpacecraft,
                            Atmosphere inAtmosphere,
                            int inSquaringPoints,
                            double inEarthRadius,
                            double inAtmoThreshold,
                            int inDragRecomputeStep)

Constructor.

Fourier Series order for short periods computation is set to default value: 10.

Parameters:

inSpacecraft - the drag sensitive spacecraft.

inAtmosphere - the atmospheric model.

inSquaringPoints - number of points for Simpson' Squaring.

inEarthRadius - the Earth radius.

inAtmoThreshold - the altitude of the upper atmospheric boundary.

inDragRecomputeStep - drag will be re-computed every inDragRecomputeStep steps (if value is 0, computed every substep)

StelaAtmosphericDrag

public StelaAtmosphericDrag(DragSensitive inSpacecraft,
                            Atmosphere inAtmosphere,
                            int inSquaringPoints,
                            double inEarthRadius,
                            double inAtmoThreshold,
                            int inDragRecomputeStep,
                            int orderFS)

Constructor.

Parameters:

inSpacecraft - the drag sensitive spacecraft.

inAtmosphere - the atmospheric model.

inSquaringPoints - number of points for Simpson' Squaring.

inEarthRadius - the Earth radius.

inAtmoThreshold - the altitude of the upper atmospheric boundary.

inDragRecomputeStep - drag will be re-computed every inDragRecomputeStep steps (if value is 0, computed every substep)

orderFS - Fourier Series order for short periods computation

Method Detail

getDragRecomputeStep

public int getDragRecomputeStep()

Returns:

the dragRecomputeStep

computePerturbation

public double[] computePerturbation(StelaEquinoctialOrbit orbit,
                                    OrbitNatureConverter converter)
                             throws PatriusException

Compute the dE/dt force derivatives for a given spacecraft state.

Specified by:

computePerturbation in class AbstractStelaGaussContribution

Parameters:

orbit - current orbit information: date, kinematics

converter - mean / osculating parameters converter

Returns:

the perturbation dE/dt for the current force

Throws:

PatriusException - if perturbation computation fails

computeShortPeriods

public double[] computeShortPeriods(StelaEquinoctialOrbit orbit,
                                    OrbitNatureConverter converter)
                             throws PatriusException

Compute the short periodic variations for a given spacecraft state.

Parameters:

orbit - current orbit information: date, kinematics

converter - converter necessary in some specific case (drag short periods computation)

Returns:

the short periodic variations of the current force

Throws:

PatriusException - if short periods computation fails

computePartialDerivatives

public double[][] computePartialDerivatives(StelaEquinoctialOrbit orbit)
                                     throws PatriusException

Compute the partial derivatives for a given spacecraft state.

Parameters:

orbit - current orbit information: date, kinematics

Returns:

the partial derivatives of the current force

Throws:

PatriusException - if partial derivatives computation fails

computeAnomalyBounds

protected double[] computeAnomalyBounds(double a,
                                        double e,
                                        double za)

Computes true anomaly and eccentric anomaly bounds.

Parameters:

a - semi-major axis

e - eccentricity

za - apogee altitude

Returns:

True anomaly and eccentric anomaly bounds.

setTransMatComputationFlag

public void setTransMatComputationFlag(boolean transMatrixFlag)

Setter for the switch indicating whether the drag term of the transition matrix has to be computed.

Parameters:

transMatrixFlag - flag to set