org.orekit.propagation.semianalytical.dsst.forces

Class DSSTThirdBody

java.lang.Object

org.orekit.propagation.semianalytical.dsst.forces.DSSTThirdBody

All Implemented Interfaces:

DSSTForceModel

public class DSSTThirdBody
extends Object
implements DSSTForceModel

Third body attraction perturbation to the DSSTPropagator.

Author:

Romain Di Costanzo, Pascal Parraud, Bryan Cazabonne (field translation)

Field Summary

Fields

Modifier and Type	Field and Description
static String	ATTRACTION_COEFFICIENT Name of the single parameter of this model: the attraction coefficient.
static String	SHORT_PERIOD_PREFIX Name of the prefix for short period coefficients keys.

Constructor Summary

Constructors

Constructor and Description
DSSTThirdBody(CelestialBody body, double mu) Complete constructor.

Method Summary

Modifier and Type	Method and Description
CelestialBody	getBody() Get third body.
EventDetector[]	getEventsDetectors() Get the discrete events related to the model.
<T extends CalculusFieldElement<T>> FieldEventDetector<T>[]	getFieldEventsDetectors(Field<T> field) Get the discrete events related to the model.
<T extends CalculusFieldElement<T>> T[]	getMeanElementRate(FieldSpacecraftState<T> currentState, FieldAuxiliaryElements<T> auxiliaryElements, T[] parameters) Computes the mean equinoctial elements rates dai / dt.
double[]	getMeanElementRate(SpacecraftState currentState, AuxiliaryElements auxiliaryElements, double[] parameters) Computes the mean equinoctial elements rates dai / dt.
List<ParameterDriver>	getParametersDrivers() Get the drivers for force model parameters.
List<ShortPeriodTerms>	initializeShortPeriodTerms(AuxiliaryElements auxiliaryElements, PropagationType type, double[] parameters) Computes the highest power of the eccentricity and the highest power of a/R3 to appear in the truncated analytical power series expansion.
<T extends CalculusFieldElement<T>> List<FieldShortPeriodTerms<T>>	initializeShortPeriodTerms(FieldAuxiliaryElements<T> auxiliaryElements, PropagationType type, T[] parameters) Performs initialization prior to propagation for the current force model.
void	registerAttitudeProvider(AttitudeProvider provider) Register an attitude provider.
void	updateShortPeriodTerms(double[] parameters, SpacecraftState... meanStates) Update the short period terms.
<T extends CalculusFieldElement<T>> void	updateShortPeriodTerms(T[] parameters, FieldSpacecraftState<T>... meanStates) Update the short period terms.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.orekit.propagation.semianalytical.dsst.forces.DSSTForceModel

getParameters, getParameters, init, init

Field Detail

SHORT_PERIOD_PREFIX

public static final String SHORT_PERIOD_PREFIX

Name of the prefix for short period coefficients keys.

See Also:

Constant Field Values

ATTRACTION_COEFFICIENT

public static final String ATTRACTION_COEFFICIENT

Name of the single parameter of this model: the attraction coefficient.

See Also:

Constant Field Values

Constructor Detail

DSSTThirdBody

public DSSTThirdBody(CelestialBody body,
                     double mu)

Complete constructor.

Parameters:

body - the 3rd body to consider

mu - central attraction coefficient

See Also:

CelestialBodies

Method Detail

getBody

public CelestialBody getBody()

Get third body.

Returns:

third body

initializeShortPeriodTerms

public List<ShortPeriodTerms> initializeShortPeriodTerms(AuxiliaryElements auxiliaryElements,
                                                         PropagationType type,
                                                         double[] parameters)

Computes the highest power of the eccentricity and the highest power of a/R3 to appear in the truncated analytical power series expansion.

This method computes the upper value for the 3rd body potential and determines the maximal powers for the eccentricity and a/R3 producing potential terms bigger than a defined tolerance.

Specified by:

initializeShortPeriodTerms in interface DSSTForceModel

Parameters:

auxiliaryElements - auxiliary elements related to the current orbit

type - type of the elements used during the propagation

parameters - values of the force model parameters

Returns:

a list of objects that will hold short period terms (the objects are also retained by the force model, which will update them during propagation)

initializeShortPeriodTerms

public <T extends CalculusFieldElement<T>> List<FieldShortPeriodTerms<T>> initializeShortPeriodTerms(FieldAuxiliaryElements<T> auxiliaryElements,
                                                                                                     PropagationType type,
                                                                                                     T[] parameters)

Performs initialization prior to propagation for the current force model.

This method aims at being called at the very beginning of a propagation.

Specified by:

initializeShortPeriodTerms in interface DSSTForceModel

Type Parameters:

T - type of the elements

Parameters:

auxiliaryElements - auxiliary elements related to the current orbit

type - type of the elements used during the propagation

parameters - values of the force model parameters

Returns:

a list of objects that will hold short period terms (the objects are also retained by the force model, which will update them during propagation)

getMeanElementRate

public double[] getMeanElementRate(SpacecraftState currentState,
                                   AuxiliaryElements auxiliaryElements,
                                   double[] parameters)

Computes the mean equinoctial elements rates da_i / dt.

Specified by:

getMeanElementRate in interface DSSTForceModel

Parameters:

currentState - current state information: date, kinematics, attitude

auxiliaryElements - auxiliary elements related to the current orbit

parameters - values of the force model parameters

Returns:

the mean element rates dai/dt

getMeanElementRate

public <T extends CalculusFieldElement<T>> T[] getMeanElementRate(FieldSpacecraftState<T> currentState,
                                                                  FieldAuxiliaryElements<T> auxiliaryElements,
                                                                  T[] parameters)

Computes the mean equinoctial elements rates da_i / dt.

Specified by:

getMeanElementRate in interface DSSTForceModel

Type Parameters:

T - type of the elements

Parameters:

currentState - current state information: date, kinematics, attitude

auxiliaryElements - auxiliary elements related to the current orbit

parameters - values of the force model parameters

Returns:

the mean element rates dai/dt

updateShortPeriodTerms

public void updateShortPeriodTerms(double[] parameters,
                                   SpacecraftState... meanStates)

Update the short period terms.

The short period terms that will be updated are the ones that were returned during the call to DSSTForceModel.initializeShortPeriodTerms(AuxiliaryElements, PropagationType, double[]).

Specified by:

updateShortPeriodTerms in interface DSSTForceModel

Parameters:

parameters - values of the force model parameters

meanStates - mean states information: date, kinematics, attitude

updateShortPeriodTerms

public <T extends CalculusFieldElement<T>> void updateShortPeriodTerms(T[] parameters,
                                                                       FieldSpacecraftState<T>... meanStates)

Update the short period terms.

The short period terms that will be updated are the ones that were returned during the call to DSSTForceModel.initializeShortPeriodTerms(AuxiliaryElements, PropagationType, double[]).

Specified by:

updateShortPeriodTerms in interface DSSTForceModel

Type Parameters:

T - type of the elements

Parameters:

parameters - values of the force model parameters

meanStates - mean states information: date, kinematics, attitude

getEventsDetectors

public EventDetector[] getEventsDetectors()

Get the discrete events related to the model.

Specified by:

getEventsDetectors in interface DSSTForceModel

Returns:

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

getFieldEventsDetectors

public <T extends CalculusFieldElement<T>> FieldEventDetector<T>[] getFieldEventsDetectors(Field<T> field)

Get the discrete events related to the model.

Specified by:

getFieldEventsDetectors in interface DSSTForceModel

Type Parameters:

T - type of the elements

Parameters:

field - field used by default

Returns:

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

registerAttitudeProvider

public void registerAttitudeProvider(AttitudeProvider provider)

Register an attitude provider.

Register an attitude provider that can be used by the force model.

Specified by:

registerAttitudeProvider in interface DSSTForceModel

Parameters:

provider - the AttitudeProvider

getParametersDrivers

public List<ParameterDriver> getParametersDrivers()

Get the drivers for force model parameters.

Specified by:

getParametersDrivers in interface DSSTForceModel

Returns:

drivers for force model parameters