org.orekit.forces.radiation
Class SolarRadiationPressure

java.lang.Object
  org.orekit.parameter.Parameterizable
      org.orekit.parameter.JacobiansParameterizable
          org.orekit.forces.radiation.SolarRadiationPressure

All Implemented Interfaces:

Serializable, ForceModel, GradientModel, IJacobiansParameterizable, IParameterizable

public class SolarRadiationPressure
extends JacobiansParameterizable
implements ForceModel, GradientModel

Solar radiation pressure force model.

The implementation of this class enables the computation of partial derivatives with respect to absorption, specular reflection or diffusion reflection coefficients.

Author:

Fabien Maussion, Édouard Delente, Véronique Pommier-Maurussane, Pascal Parraud

See Also:

Serialized Form

Field Summary

static String

REFERENCE_FLUX Normalized reference flux.

Constructor Summary

SolarRadiationPressure(double dRef, double pRef, PVCoordinatesProvider sun, double equatorialRadius, RadiationSensitive spacecraft)
Complete constructor.

SolarRadiationPressure(double dRef, double pRef, PVCoordinatesProvider sun, double equatorialRadius, RadiationSensitive spacecraft, boolean computePD)
Complete constructor.

SolarRadiationPressure(Parameter refFlux, PVCoordinatesProvider sun, double equatorialRadius, RadiationSensitive spacecraft)
Complete constructor.

SolarRadiationPressure(Parameter refFlux, PVCoordinatesProvider sun, double equatorialRadius, RadiationSensitive spacecraft, boolean computePD)
Complete constructor.

SolarRadiationPressure(PVCoordinatesProvider sun, double equatorialRadius, RadiationSensitive spacecraft)
Simple constructor with default reference values.

SolarRadiationPressure(PVCoordinatesProvider sun, double equatorialRadius, RadiationSensitive spacecraft, boolean computePD)
Simple constructor with default reference values.

Method Summary

void	addContribution(SpacecraftState s, TimeDerivativesEquations adder) Compute the contribution of the force model to the perturbing acceleration.
void	addDAccDParam(SpacecraftState s, Parameter param, double[] dAccdParam) Compute acceleration derivatives with respect to additional parameters.
void	addDAccDState(SpacecraftState s, double[][] dAccdPos, double[][] dAccdVel) Compute acceleration derivatives with respect to state parameters.
Vector3D	computeAcceleration(SpacecraftState s) Compute the acceleration due to the force.
boolean	computeGradientPosition() This method returns true if the acceleration partial derivatives with respect to position have to be computed.
boolean	computeGradientVelocity() This method returns true if the acceleration partial derivatives with respect to velocity have to be computed.
EventDetector[]	getEventsDetectors() Get the discrete events related to the model.
double	getLightningRatio(Vector3D position, Frame frame, AbsoluteDate date) Get the lightning ratio ([0-1]).

Methods inherited from class org.orekit.parameter.JacobiansParameterizable

addJacobiansParameter, addJacobiansParameter, addJacobiansParameter, supportsJacobianParameter

Methods inherited from class org.orekit.parameter.Parameterizable

addParameter, getParameters, supportsParameter

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.orekit.parameter.IParameterizable

getParameters, supportsParameter

Field Detail

REFERENCE_FLUX

public static final String REFERENCE_FLUX

Normalized reference flux.

See Also:

Constant Field Values

Constructor Detail

SolarRadiationPressure

public SolarRadiationPressure(PVCoordinatesProvider sun,
                              double equatorialRadius,
                              RadiationSensitive spacecraft)

Simple constructor with default reference values.

When this constructor is used, the reference values are:

• d_ref = 149597870000 m
• p_ref = 4.56 10^-6 N/m²

Parameters:

sun - Sun model

equatorialRadius - spherical shape model (for umbra/penumbra computation)

spacecraft - the object physical and geometrical information

SolarRadiationPressure

public SolarRadiationPressure(PVCoordinatesProvider sun,
                              double equatorialRadius,
                              RadiationSensitive spacecraft,
                              boolean computePD)

Simple constructor with default reference values.

When this constructor is used, the reference values are:

• d_ref = 149597870000 m
• p_ref = 4.56 10^-6 N/m²

Parameters:

sun - Sun model

equatorialRadius - spherical shape model (for umbra/penumbra computation)

spacecraft - the object physical and geometrical information

computePD - true if partial derivatives wrt position have to be computed

SolarRadiationPressure

public SolarRadiationPressure(double dRef,
                              double pRef,
                              PVCoordinatesProvider sun,
                              double equatorialRadius,
                              RadiationSensitive spacecraft)

Complete constructor.

Note that reference solar radiation pressure pRef in N/m² is linked to solar flux SF in W/m² using formula pRef = SF/c where c is the speed of light (299792458 m/s). So at 1UA a 1367 W/m² solar flux is a 4.56 10^-6 N/m² solar radiation pressure.

Parameters:

dRef - reference distance for the solar radiation pressure (m)

pRef - reference solar radiation pressure at dRef (N/m²)

sun - Sun model

equatorialRadius - spherical shape model (for umbra/penumbra computation)

spacecraft - the object physical and geometrical information

SolarRadiationPressure

public SolarRadiationPressure(double dRef,
                              double pRef,
                              PVCoordinatesProvider sun,
                              double equatorialRadius,
                              RadiationSensitive spacecraft,
                              boolean computePD)

Complete constructor.

Note that reference solar radiation pressure pRef in N/m² is linked to solar flux SF in W/m² using formula pRef = SF/c where c is the speed of light (299792458 m/s). So at 1UA a 1367 W/m² solar flux is a 4.56 10^-6 N/m² solar radiation pressure.

Parameters:

dRef - reference distance for the solar radiation pressure (m)

pRef - reference solar radiation pressure at dRef (N/m²)

sun - Sun model

equatorialRadius - spherical shape model (for umbra/penumbra computation)

spacecraft - the object physical and geometrical information

computePD - true if partial derivatives wrt position have to be computed

SolarRadiationPressure

public SolarRadiationPressure(Parameter refFlux,
                              PVCoordinatesProvider sun,
                              double equatorialRadius,
                              RadiationSensitive spacecraft)

Complete constructor.

Parameters:

refFlux - parameter representing the reference flux normalized for a 1m distance (N)

sun - Sun model

equatorialRadius - spherical shape model (for umbra/penumbra computation)

spacecraft - the object physical and geometrical information

SolarRadiationPressure

public SolarRadiationPressure(Parameter refFlux,
                              PVCoordinatesProvider sun,
                              double equatorialRadius,
                              RadiationSensitive spacecraft,
                              boolean computePD)

Complete constructor.

Parameters:

refFlux - parameter representing the reference flux normalized for a 1m distance (N)

sun - Sun model

equatorialRadius - spherical shape model (for umbra/penumbra computation)

spacecraft - the object physical and geometrical information

computePD - true if partial derivatives wrt position have to be computed

Method Detail

computeAcceleration

public Vector3D computeAcceleration(SpacecraftState s)
                             throws OrekitException

Compute the acceleration due to the force.

Specified by:

computeAcceleration in interface ForceModel

Parameters:

s - current state information: date, kinematics, attitude

Returns:

acceleration in the SpacecraftState frame

Throws:

OrekitException - if some specific error occurs

addContribution

public void addContribution(SpacecraftState s,
                            TimeDerivativesEquations adder)
                     throws OrekitException

Compute the contribution of the force model to the perturbing acceleration.

Specified by:

addContribution in interface ForceModel

Parameters:

s - current state information: date, kinematics, attitude

adder - object where the contribution should be added

Throws:

OrekitException - if some specific error occurs

getLightningRatio

public double getLightningRatio(Vector3D position,
                                Frame frame,
                                AbsoluteDate date)
                         throws OrekitException

Get the lightning ratio ([0-1]).

Parameters:

position - the satellite's position in the selected frame.

frame - in which is defined the position

date - the date

Returns:

lightning ratio

Throws:

OrekitException - if an error occurs

getEventsDetectors

public EventDetector[] getEventsDetectors()

Get the discrete events related to the model.

Specified by:

getEventsDetectors in interface ForceModel

Returns:

array of events detectors or null if the model is not related to any discrete events

addDAccDState

public void addDAccDState(SpacecraftState s,
                          double[][] dAccdPos,
                          double[][] dAccdVel)
                   throws OrekitException

Compute acceleration derivatives with respect to state parameters.

Specified by:

addDAccDState in interface IJacobiansParameterizable

Parameters:

s - spacecraft state

dAccdPos - acceleration derivatives with respect to position

dAccdVel - acceleration derivatives with respect to velocity

Throws:

OrekitException - if derivatives cannot be computed

addDAccDParam

public void addDAccDParam(SpacecraftState s,
                          Parameter param,
                          double[] dAccdParam)
                   throws OrekitException

Compute acceleration derivatives with respect to additional parameters..

Specified by:

addDAccDParam in interface IJacobiansParameterizable

Parameters:

s - spacecraft state

param - the parameter with respect to which derivatives are required

dAccdParam - acceleration derivatives with respect to specified parameters

Throws:

OrekitException - if derivatives cannot be computed

computeGradientPosition

public boolean computeGradientPosition()

This method returns true if the acceleration partial derivatives with respect to position have to be computed.

Specified by:

computeGradientPosition in interface GradientModel

Returns:

true if the derivatives have to be computed, false otherwise

computeGradientVelocity

public boolean computeGradientVelocity()

This method returns true if the acceleration partial derivatives with respect to velocity have to be computed.

Specified by:

computeGradientVelocity in interface GradientModel

Returns:

true if the derivatives have to be computed, false otherwise