org.orekit.forces.drag
Class DragForce

java.lang.Object
  org.orekit.forces.drag.DragForce

All Implemented Interfaces:

java.io.Serializable, ForceModel, ForceModelWithJacobians, Parameterizable

public class DragForce
extends java.lang.Object
implements ForceModelWithJacobians

Atmospheric drag force model. The drag acceleration is computed as follows : &gamma = (1/2 * Ro * V² * S / Mass) * DragCoefVector With DragCoefVector = {Cx, Cy, Cz} and S given by the user through the interface DragSensitive

Version:

$Revision:1665 $ $Date:2008-06-11 12:12:59 +0200 (mer., 11 juin 2008) $

Author:

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

See Also:

Serialized Form

Field Summary

static java.lang.String

DRAG_COEFFICIENT Parameter name for drag coefficient enabling jacobian processing.

Constructor Summary

DragForce(Atmosphere atmosphere, DragSensitive spacecraft)
Simple constructor.

Method Summary

void	addContribution(SpacecraftState s, TimeDerivativesEquations adder) Compute the contribution of the drag to the perturbing acceleration.
void	addContributionWithJacobians(SpacecraftState s, TimeDerivativesEquationsWithJacobians adder) Compute the contribution of the force model to the perturbing acceleration and to the jacobians.
EventDetector[]	getEventsDetectors() There are no discrete events for this model.
double	getParameter(java.lang.String name) Get parameter value from its name.
java.util.Collection<java.lang.String>	getParametersNames() Get the names of the supported parameters for partial derivatives processing.
void	setParameter(java.lang.String name, double value) Set the value for a given parameter.

Methods inherited from class java.lang.Object

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

Field Detail

DRAG_COEFFICIENT

public static final java.lang.String DRAG_COEFFICIENT

Parameter name for drag coefficient enabling jacobian processing.

See Also:

Constant Field Values

Constructor Detail

DragForce

public DragForce(Atmosphere atmosphere,
                 DragSensitive spacecraft)

Simple constructor.

Parameters:

atmosphere - atmospheric model

spacecraft - the object physical and geometrical information

Method Detail

addContribution

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

Compute the contribution of the drag to the perturbing acceleration.

Specified by:

addContribution in interface ForceModel

Parameters:

s - the current state information : date, kinematics, attitude

adder - object where the contribution should be added

Throws:

OrekitException - if some specific error occurs

getEventsDetectors

public EventDetector[] getEventsDetectors()

There are no discrete events for this model.

Specified by:

getEventsDetectors in interface ForceModel

Returns:

an empty array

addContributionWithJacobians

public void addContributionWithJacobians(SpacecraftState s,
                                         TimeDerivativesEquationsWithJacobians adder)
                                  throws OrekitException

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

Specified by:

addContributionWithJacobians in interface ForceModelWithJacobians

Parameters:

s - current state information: date, kinematics, attitude

adder - object where the contribution should be added

Throws:

OrekitException - if some specific error occurs

getParametersNames

public java.util.Collection<java.lang.String> getParametersNames()

Get the names of the supported parameters for partial derivatives processing.

Specified by:

getParametersNames in interface Parameterizable

Returns:

parameters names

getParameter

public double getParameter(java.lang.String name)
                    throws java.lang.IllegalArgumentException

Get parameter value from its name.

Specified by:

getParameter in interface Parameterizable

Parameters:

name - parameter name

Returns:

parameter value

Throws:

java.lang.IllegalArgumentException - if parameter is not supported

setParameter

public void setParameter(java.lang.String name,
                         double value)
                  throws java.lang.IllegalArgumentException

Set the value for a given parameter.

Specified by:

setParameter in interface Parameterizable

Parameters:

name - parameter name

value - parameter value

Throws:

java.lang.IllegalArgumentException - if parameter is not supported