org.orekit.forces

Class SphericalSpacecraft

java.lang.Object

org.orekit.forces.SphericalSpacecraft

All Implemented Interfaces:

DragSensitive, RadiationSensitive

public class SphericalSpacecraft
extends Object
implements RadiationSensitive, DragSensitive

This class represents the features of a simplified spacecraft.

The model of this spacecraft is a simple spherical model, this means that all coefficients are constant and do not depend of the direction.

Instances of this class are guaranteed to be immutable.

Author:

Édouard Delente, Fabien Maussion, Pascal Parraud

See Also:

BoxAndSolarArraySpacecraft

Field Summary

Fields inherited from interface org.orekit.forces.radiation.RadiationSensitive

ABSORPTION_COEFFICIENT, REFLECTION_COEFFICIENT

Fields inherited from interface org.orekit.forces.drag.DragSensitive

DRAG_COEFFICIENT

Constructor Summary

Constructors

Constructor and Description
SphericalSpacecraft(double crossSection, double dragCoeff, double absorptionCoeff, double reflectionCoeff) Simple constructor.

Method Summary

Methods

Modifier and Type	Method and Description
FieldVector3D<DerivativeStructure>	dragAcceleration(AbsoluteDate date, Frame frame, FieldVector3D<DerivativeStructure> position, FieldRotation<DerivativeStructure> rotation, DerivativeStructure mass, double density, FieldVector3D<DerivativeStructure> relativeVelocity) Compute the acceleration due to drag, with state derivatives.
Vector3D	dragAcceleration(AbsoluteDate date, Frame frame, Vector3D position, Rotation rotation, double mass, double density, Vector3D relativeVelocity) Compute the acceleration due to drag.
FieldVector3D<DerivativeStructure>	dragAcceleration(AbsoluteDate date, Frame frame, Vector3D position, Rotation rotation, double mass, double density, Vector3D relativeVelocity, String paramName) Compute acceleration due to drag, with parameters derivatives.
double	getAbsorptionCoefficient() Get the absorption coefficient.
double	getDragCoefficient() Get the drag coefficient.
double	getReflectionCoefficient() Get the specular reflection coefficient.
FieldVector3D<DerivativeStructure>	radiationPressureAcceleration(AbsoluteDate date, Frame frame, FieldVector3D<DerivativeStructure> position, FieldRotation<DerivativeStructure> rotation, DerivativeStructure mass, FieldVector3D<DerivativeStructure> flux) Compute the acceleration due to radiation pressure, with state derivatives.
Vector3D	radiationPressureAcceleration(AbsoluteDate date, Frame frame, Vector3D position, Rotation rotation, double mass, Vector3D flux) Compute the acceleration due to radiation pressure.
FieldVector3D<DerivativeStructure>	radiationPressureAcceleration(AbsoluteDate date, Frame frame, Vector3D position, Rotation rotation, double mass, Vector3D flux, String paramName) Compute the acceleration due to radiation pressure, with parameters derivatives.
void	setAbsorptionCoefficient(double value) Set the absorption coefficient.
void	setDragCoefficient(double value) Set the drag coefficient.
void	setReflectionCoefficient(double value) Set the specular reflection coefficient.

Methods inherited from class java.lang.Object

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

Constructor Detail

SphericalSpacecraft

public SphericalSpacecraft(double crossSection,
                   double dragCoeff,
                   double absorptionCoeff,
                   double reflectionCoeff)

Simple constructor.

Parameters:

crossSection - Surface (m²)

dragCoeff - drag coefficient (used only for drag)

absorptionCoeff - absorption coefficient between 0.0 an 1.0 (used only for radiation pressure)

reflectionCoeff - specular reflection coefficient between 0.0 an 1.0 (used only for radiation pressure)

Method Detail

dragAcceleration

public Vector3D dragAcceleration(AbsoluteDate date,
                        Frame frame,
                        Vector3D position,
                        Rotation rotation,
                        double mass,
                        double density,
                        Vector3D relativeVelocity)

Compute the acceleration due to drag.

The computation includes all spacecraft specific characteristics like shape, area and coefficients.

Specified by:

dragAcceleration in interface DragSensitive

Parameters:

date - current date

frame - inertial reference frame for state (both orbit and attitude)

position - position of spacecraft in reference frame

rotation - orientation (attitude) of the spacecraft with respect to reference frame

mass - current mass

density - atmospheric density at spacecraft position

relativeVelocity - relative velocity of atmosphere with respect to spacecraft, in the same inertial frame as spacecraft orbit (m/s)

Returns:

spacecraft acceleration in the same inertial frame as spacecraft orbit (m/s²)

dragAcceleration

public FieldVector3D<DerivativeStructure> dragAcceleration(AbsoluteDate date,
                                                  Frame frame,
                                                  FieldVector3D<DerivativeStructure> position,
                                                  FieldRotation<DerivativeStructure> rotation,
                                                  DerivativeStructure mass,
                                                  double density,
                                                  FieldVector3D<DerivativeStructure> relativeVelocity)

Compute the acceleration due to drag, with state derivatives.

The computation includes all spacecraft specific characteristics like shape, area and coefficients.

Specified by:

dragAcceleration in interface DragSensitive

Parameters:

date - current date

frame - inertial reference frame for state (both orbit and attitude)

position - position of spacecraft in reference frame

rotation - orientation (attitude) of the spacecraft with respect to reference frame

mass - spacecraft mass

density - atmospheric density at spacecraft position

relativeVelocity - relative velocity of atmosphere with respect to spacecraft, in the same inertial frame as spacecraft orbit (m/s)

Returns:

spacecraft acceleration in the same inertial frame as spacecraft orbit (m/s²)

dragAcceleration

public FieldVector3D<DerivativeStructure> dragAcceleration(AbsoluteDate date,
                                                  Frame frame,
                                                  Vector3D position,
                                                  Rotation rotation,
                                                  double mass,
                                                  double density,
                                                  Vector3D relativeVelocity,
                                                  String paramName)
                                                    throws OrekitException

Compute acceleration due to drag, with parameters derivatives.

Specified by:

dragAcceleration in interface DragSensitive

Parameters:

date - current date

frame - inertial reference frame for state (both orbit and attitude)

position - position of spacecraft in reference frame

rotation - orientation (attitude) of the spacecraft with respect to reference frame

mass - current mass

density - atmospheric density at spacecraft position

relativeVelocity - relative velocity of atmosphere with respect to spacecraft, in the same inertial frame as spacecraft orbit (m/s)

paramName - name of the parameter with respect to which derivatives are required

Returns:

spacecraft acceleration in the same inertial frame as spacecraft orbit (m/s²)

Throws:

OrekitException - if derivatives cannot be computed

radiationPressureAcceleration

public Vector3D radiationPressureAcceleration(AbsoluteDate date,
                                     Frame frame,
                                     Vector3D position,
                                     Rotation rotation,
                                     double mass,
                                     Vector3D flux)

Compute the acceleration due to radiation pressure.

Specified by:

radiationPressureAcceleration in interface RadiationSensitive

Parameters:

date - current date

frame - inertial reference frame for state (both orbit and attitude)

position - position of spacecraft in reference frame

rotation - orientation (attitude) of the spacecraft with respect to reference frame

mass - current mass

flux - radiation flux in the same inertial frame as spacecraft orbit

Returns:

spacecraft acceleration in the same inertial frame as spacecraft orbit (m/s²)

radiationPressureAcceleration

public FieldVector3D<DerivativeStructure> radiationPressureAcceleration(AbsoluteDate date,
                                                               Frame frame,
                                                               FieldVector3D<DerivativeStructure> position,
                                                               FieldRotation<DerivativeStructure> rotation,
                                                               DerivativeStructure mass,
                                                               FieldVector3D<DerivativeStructure> flux)

Compute the acceleration due to radiation pressure, with state derivatives.

Specified by:

radiationPressureAcceleration in interface RadiationSensitive

Parameters:

date - current date

frame - inertial reference frame for state (both orbit and attitude)

position - position of spacecraft in reference frame

rotation - orientation (attitude) of the spacecraft with respect to reference frame

mass - spacecraft mass

flux - radiation flux in the same inertial frame as spacecraft orbit

Returns:

spacecraft acceleration in the same inertial frame as spacecraft orbit (m/s²)

radiationPressureAcceleration

public FieldVector3D<DerivativeStructure> radiationPressureAcceleration(AbsoluteDate date,
                                                               Frame frame,
                                                               Vector3D position,
                                                               Rotation rotation,
                                                               double mass,
                                                               Vector3D flux,
                                                               String paramName)
                                                                 throws OrekitException

Compute the acceleration due to radiation pressure, with parameters derivatives.

Specified by:

radiationPressureAcceleration in interface RadiationSensitive

Parameters:

date - current date

frame - inertial reference frame for state (both orbit and attitude)

position - position of spacecraft in reference frame

rotation - orientation (attitude) of the spacecraft with respect to reference frame

mass - current mass

flux - radiation flux in the same inertial frame as spacecraft orbit

paramName - name of the parameter with respect to which derivatives are required

Returns:

spacecraft acceleration in the same inertial frame as spacecraft orbit (m/s²)

Throws:

OrekitException - if acceleration cannot be computed

setDragCoefficient

public void setDragCoefficient(double value)

Set the drag coefficient.

Specified by:

setDragCoefficient in interface DragSensitive

Parameters:

value - drag coefficient

getDragCoefficient

public double getDragCoefficient()

Get the drag coefficient.

Specified by:

getDragCoefficient in interface DragSensitive

Returns:

drag coefficient

setAbsorptionCoefficient

public void setAbsorptionCoefficient(double value)

Set the absorption coefficient.

Specified by:

setAbsorptionCoefficient in interface RadiationSensitive

Parameters:

value - absorption coefficient

getAbsorptionCoefficient

public double getAbsorptionCoefficient()

Get the absorption coefficient.

Specified by:

getAbsorptionCoefficient in interface RadiationSensitive

Returns:

absorption coefficient

setReflectionCoefficient

public void setReflectionCoefficient(double value)

Set the specular reflection coefficient.

Specified by:

setReflectionCoefficient in interface RadiationSensitive

Parameters:

value - specular reflection coefficient

getReflectionCoefficient

public double getReflectionCoefficient()

Get the specular reflection coefficient.

Specified by:

getReflectionCoefficient in interface RadiationSensitive

Returns:

reflection coefficient