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

Class StelaAeroModel

java.lang.Object

fr.cnes.sirius.patrius.math.parameter.Parameterizable

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

All Implemented Interfaces:

DragSensitive, IParameterizable, JacobianParametersProvider, Serializable

public final class StelaAeroModel
extends Parameterizable
implements DragSensitive

This class represents a STELA aero model, based on a spherical spacecraft.

It contains the STELA algorithm for the drag computation, as well as the STELA algorithm for the computation of the partial derivatives with respect to position and velocity, in the TNW frame.
As this class is an implementation of the DragSensitive interface, it is intended to be used in the StelaAtmosphericDrag class.

Since:

1.3

Version:

$Id$

Author:

Tiziana Sabatini

See Also:

AeroModel, StelaAtmosphericDrag, Serialized Form

Concurrency :

immutable

Constructor Summary

Constructors

Constructor and Description
StelaAeroModel(double inMass, StelaCd inCd, double inSurface) Constructor to be used when partial derivatives should not be computed.
StelaAeroModel(double inMass, StelaCd inCd, double inSurface, Atmosphere inAtmosphere, double atmosDX) Constructor to be used when partial derivatives are computed using the full finite differences method.
StelaAeroModel(double inMass, StelaCd inCd, double inSurface, Atmosphere inAtmosphere, double atmosDH, GeodPosition inGeodPosition) Constructor to be used when partial derivatives are computed using the altitude finite differences method.

Method Summary

Modifier and Type	Method and Description
void	addDDragAccDParam(SpacecraftState s, Parameter param, double density, Vector3D relativeVelocity, double[] dAccdParam) Compute acceleration derivatives with respect to additional parameters (the ballistic coefficient).
void	addDDragAccDState(SpacecraftState s, double[][] dAccdPos, double[][] dAccdVel, double density, Vector3D acceleration, Vector3D relativeVelocity, boolean computeGradientPosition, boolean computeGradientVelocity) Compute acceleration derivatives with respect to state parameters (position and velocity).
DragSensitive	copy(Assembly assembly) Copy drag sensitive object using new assembly.
Vector3D	dragAcceleration(SpacecraftState state, double density, Vector3D relativeVelocity) Return the drag acceleration in the CIRF frame.
ArrayList<Parameter>	getJacobianParameters() Get the list of all jacobian parameters supported.

Methods inherited from class fr.cnes.sirius.patrius.math.parameter.Parameterizable

addAllParameters, addAllParameters, addParameter, getParameters, supportsParameter

Methods inherited from class java.lang.Object

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

Constructor Detail

StelaAeroModel

public StelaAeroModel(double inMass,
                      StelaCd inCd,
                      double inSurface)
               throws PatriusException

Constructor to be used when partial derivatives should not be computed.

Parameters:

inMass - the spacecraft mass.

inCd - the spacecraft drag coefficient.

inSurface - the spacecraft cross section (m²).

Throws:

PatriusException - if the frame factory fails.

StelaAeroModel

public StelaAeroModel(double inMass,
                      StelaCd inCd,
                      double inSurface,
                      Atmosphere inAtmosphere,
                      double atmosDX)
               throws PatriusException

Constructor to be used when partial derivatives are computed using the full finite differences method.

Parameters:

inMass - the spacecraft mass.

inCd - the spacecraft drag coefficient.

inSurface - the spacecraft cross section (m²).

inAtmosphere - the atmospheric model

atmosDX - dX in atmospheric density derivatives full finite differences computation

Throws:

PatriusException - if the frame factory fails.

StelaAeroModel

public StelaAeroModel(double inMass,
                      StelaCd inCd,
                      double inSurface,
                      Atmosphere inAtmosphere,
                      double atmosDH,
                      GeodPosition inGeodPosition)
               throws PatriusException

Constructor to be used when partial derivatives are computed using the altitude finite differences method.

Parameters:

inMass - the spacecraft mass.

inCd - the spacecraft drag coefficient.

inSurface - the spacecraft cross section (m²).

inAtmosphere - the atmospheric model

atmosDH - dH in atmospheric density derivatives altitude finite differences computation

inGeodPosition - the spacecraft geodetic position model

Throws:

PatriusException - if the frame factory fails.

Method Detail

dragAcceleration

public Vector3D dragAcceleration(SpacecraftState state,
                                 double density,
                                 Vector3D relativeVelocity)
                          throws PatriusException

Return the drag acceleration in the CIRF frame.

Specified by:

dragAcceleration in interface DragSensitive

Parameters:

state - current state information: date, kinematics, attitude

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 celestial mean of date. (m/s²)

Throws:

PatriusException - if acceleration cannot be computed

addDDragAccDParam

public void addDDragAccDParam(SpacecraftState s,
                              Parameter param,
                              double density,
                              Vector3D relativeVelocity,
                              double[] dAccdParam)
                       throws PatriusException

Compute acceleration derivatives with respect to additional parameters (the ballistic coefficient).

Specified by:

addDDragAccDParam in interface DragSensitive

Parameters:

s - spacecraft state

param - parameter

density - the atmospheric density value

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

dAccdParam - acceleration derivatives with respect to ballistic coefficient

Throws:

PatriusException - if derivatives cannot be computed

addDDragAccDState

public void addDDragAccDState(SpacecraftState s,
                              double[][] dAccdPos,
                              double[][] dAccdVel,
                              double density,
                              Vector3D acceleration,
                              Vector3D relativeVelocity,
                              boolean computeGradientPosition,
                              boolean computeGradientVelocity)
                       throws PatriusException

Compute acceleration derivatives with respect to state parameters (position and velocity).

Specified by:

addDDragAccDState in interface DragSensitive

Parameters:

s - spacecraft state

dAccdPos - acceleration derivatives with respect to position parameters

dAccdVel - acceleration derivatives with respect to velocity parameters

density - the atmospheric density value

acceleration - the spacecraft acceleration in the inertial frame

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

computeGradientPosition - true if partial derivatives with respect to position should be computed

computeGradientVelocity - true if partial derivatives with respect to position should be computed

Throws:

PatriusException - if derivatives cannot be computed

getJacobianParameters

public ArrayList<Parameter> getJacobianParameters()

Get the list of all jacobian parameters supported.

Specified by:

getJacobianParameters in interface JacobianParametersProvider

Returns:

the list of additional parameters for which the jacobians can be computed.

copy

public DragSensitive copy(Assembly assembly)

Copy drag sensitive object using new assembly.

Specified by:

copy in interface DragSensitive

Parameters:

assembly - new assembly

Returns:

drag sensitive object with new assembly