org.orekit.propagation.semianalytical.dsst.forces

Class DSSTSolarRadiationPressure

java.lang.Object

org.orekit.propagation.semianalytical.dsst.forces.AbstractGaussianContribution

org.orekit.propagation.semianalytical.dsst.forces.DSSTSolarRadiationPressure

All Implemented Interfaces:

DSSTForceModel

public class DSSTSolarRadiationPressure
extends AbstractGaussianContribution

Solar radiation pressure contribution to the DSSTPropagator.

The solar radiation pressure acceleration is computed as follows:
γ = (C_R A / m) * (p_ref * d²_ref) * (r_sat - R_sun) / |r_sat - R_sun|³

Author:

Pascal Parraud

Field Summary

Fields inherited from class org.orekit.propagation.semianalytical.dsst.forces.AbstractGaussianContribution

a, A, B, C, co2AB, ecc, f, g, h, I, k, n, ooA, ooAB, ooBpo, ooMu, p, q, ton2a, w

Constructor Summary

Constructors

Constructor and Description
DSSTSolarRadiationPressure(double dRef, double pRef, double cr, double area, PVCoordinatesProvider sun, double equatorialRadius) Complete constructor.
DSSTSolarRadiationPressure(double cr, double area, PVCoordinatesProvider sun, double equatorialRadius) Simple constructor with default reference values.

Method Summary

Methods

Modifier and Type	Method and Description
protected Vector3D	getAcceleration(SpacecraftState state, Vector3D position, Vector3D velocity) Compute the acceleration due to the non conservative perturbing force.
double	getArea() Get the cross sectional area of satellite.
double	getCr() Get the satellite radiation pressure coefficient (assuming total specular reflection).
double	getEquatorialRadius() Get the central body equatorial radius.
EventDetector[]	getEventsDetectors() Get the discrete events related to the model.
protected double[]	getLLimits(SpacecraftState state) Compute the limits in L, the true longitude, for integration.
double[]	getShortPeriodicVariations(AbsoluteDate date, double[] meanElements) Computes the short periodic variations.

Methods inherited from class org.orekit.propagation.semianalytical.dsst.forces.AbstractGaussianContribution

getMeanElementRate, initialize, initializeStep

Methods inherited from class java.lang.Object

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

Constructor Detail

DSSTSolarRadiationPressure

public DSSTSolarRadiationPressure(double cr,
                          double area,
                          PVCoordinatesProvider sun,
                          double equatorialRadius)

Simple constructor with default reference values.

When this constructor is used, the reference values are:

• d_ref = 149597870000.0 m
• p_ref = 4.56 10^-6 N/m²

Parameters:

cr - satellite radiation pressure coefficient (assuming total specular reflection)

area - cross sectionnal area of satellite

sun - Sun model

equatorialRadius - central body equatorial radius (for shadow computation)

DSSTSolarRadiationPressure

public DSSTSolarRadiationPressure(double dRef,
                          double pRef,
                          double cr,
                          double area,
                          PVCoordinatesProvider sun,
                          double equatorialRadius)

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)

cr - satellite radiation pressure coefficient (assuming total specular reflection)

area - cross sectionnal area of satellite

sun - Sun model

equatorialRadius - central body equatrial radius (for shadow computation)

Method Detail

getShortPeriodicVariations

public double[] getShortPeriodicVariations(AbsoluteDate date,
                                  double[] meanElements)
                                    throws OrekitException

Computes the short periodic variations.

Parameters:

date - current date

meanElements - mean elements at current date

Returns:

the short periodic variations

Throws:

OrekitException - if some specific error occurs

getEventsDetectors

public EventDetector[] getEventsDetectors()

Get the discrete events related to the model.

Returns:

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

getAcceleration

protected Vector3D getAcceleration(SpacecraftState state,
                       Vector3D position,
                       Vector3D velocity)
                            throws OrekitException

Compute the acceleration due to the non conservative perturbing force.

Specified by:

getAcceleration in class AbstractGaussianContribution

Parameters:

state - current state information: date, kinematics, attitude

position - spacecraft position

velocity - spacecraft velocity

Returns:

the perturbing acceleration

Throws:

OrekitException - if some specific error occurs

getLLimits

protected double[] getLLimits(SpacecraftState state)
                       throws OrekitException

Compute the limits in L, the true longitude, for integration.

Specified by:

getLLimits in class AbstractGaussianContribution

Parameters:

state - current state information: date, kinematics, attitude

Returns:

the integration limits in L

Throws:

OrekitException - if some specific error occurs

getEquatorialRadius

public double getEquatorialRadius()

Get the central body equatorial radius.

Returns:

central body equatorial radius (m)

getCr

public double getCr()

Get the satellite radiation pressure coefficient (assuming total specular reflection).

Returns:

satellite radiation pressure coefficient

getArea

public double getArea()

Get the cross sectional area of satellite.

Returns:

cross sectional section (m²