Package org.orekit.propagation.semianalytical.dsst.forces

Class DSSTTesseral

java.lang.Object

org.orekit.propagation.semianalytical.dsst.forces.DSSTTesseral

All Implemented Interfaces:

EventDetectorsProvider, DSSTForceModel, ParameterDriversProvider

public class DSSTTesseral
extends Object
implements DSSTForceModel

Tesseral contribution to the central body gravitational perturbation.

Only resonant tesserals are considered.

Author:

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

Field Summary

Fields

Modifier and Type	Field	Description
static String	CM_COEFFICIENTS	Identifier for cMm coefficients.
static String	SHORT_PERIOD_PREFIX	Name of the prefix for short period coefficients keys.
static String	SM_COEFFICIENTS	Identifier for sMm coefficients.

Fields inherited from interface org.orekit.propagation.events.EventDetectorsProvider

DATATION_ACCURACY

Constructor Summary

Constructors

Constructor	Description
DSSTTesseral(Frame centralBodyFrame, double centralBodyRotationRate, UnnormalizedSphericalHarmonicsProvider provider)	Simple constructor with default reference values.
DSSTTesseral(Frame centralBodyFrame, double centralBodyRotationRate, UnnormalizedSphericalHarmonicsProvider provider, int maxDegreeTesseralSP, int maxOrderTesseralSP, int maxEccPowTesseralSP, int maxFrequencyShortPeriodics, int maxDegreeMdailyTesseralSP, int maxOrderMdailyTesseralSP, int maxEccPowMdailyTesseralSP)	Simple constructor.

Method Summary

Modifier and Type	Method	Description
<T extends CalculusFieldElement<T>> T[]	getMeanElementRate(FieldSpacecraftState<T> spacecraftState, FieldAuxiliaryElements<T> auxiliaryElements, T[] parameters)	Computes the mean equinoctial elements rates dai / dt.
double[]	getMeanElementRate(SpacecraftState spacecraftState, AuxiliaryElements auxiliaryElements, double[] parameters)	Computes the mean equinoctial elements rates dai / dt.
List<ParameterDriver>	getParametersDrivers()	Get the drivers for parameters.
List<ShortPeriodTerms>	initializeShortPeriodTerms(AuxiliaryElements auxiliaryElements, PropagationType type, double[] parameters)	Performs initialization prior to propagation for the current force model.
<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 attitudeProvider)	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

extractParameters, extractParameters, getEventDetectors, getFieldEventDetectors, init, init

Methods inherited from interface org.orekit.propagation.events.EventDetectorsProvider

getDateDetector, getEventDetectors, getFieldDateDetector, getFieldEventDetectors

Methods inherited from interface org.orekit.utils.ParameterDriversProvider

getNbParametersDriversValue, getParameterDriver, getParameters, getParameters, getParameters, getParameters, getParametersAllValues, getParametersAllValues, isSupported

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

CM_COEFFICIENTS

public static final String CM_COEFFICIENTS

Identifier for cMm coefficients.

See Also:

Constant Field Values

SM_COEFFICIENTS

public static final String SM_COEFFICIENTS

Identifier for sMm coefficients.

See Also:

Constant Field Values

Constructor Detail

DSSTTesseral

public DSSTTesseral(Frame centralBodyFrame,
                    double centralBodyRotationRate,
                    UnnormalizedSphericalHarmonicsProvider provider)

Simple constructor with default reference values.

When this constructor is used, maximum allowed values are used for the short periodic coefficients:

• maxDegreeTesseralSP is set to provider.getMaxDegree()
• maxOrderTesseralSP is set to provider.getMaxOrder().
• maxEccPowTesseralSP is set to min(4, provider.getMaxOrder())
• maxFrequencyShortPeriodics is set to min(provider.getMaxDegree() + 4, 12). This parameter should not exceed 12 as higher values will exceed computer capacity
• maxDegreeMdailyTesseralSP is set to provider.getMaxDegree()
• maxOrderMdailyTesseralSP is set to provider.getMaxOrder()
• maxEccPowMdailyTesseralSP is set to min(provider.getMaxDegree() - 2, 4). This parameter should not exceed 4 as higher values will exceed computer capacity

Parameters:

centralBodyFrame - rotating body frame

centralBodyRotationRate - central body rotation rate (rad/s)

provider - provider for spherical harmonics

Since:

10.1

DSSTTesseral

public DSSTTesseral(Frame centralBodyFrame,
                    double centralBodyRotationRate,
                    UnnormalizedSphericalHarmonicsProvider provider,
                    int maxDegreeTesseralSP,
                    int maxOrderTesseralSP,
                    int maxEccPowTesseralSP,
                    int maxFrequencyShortPeriodics,
                    int maxDegreeMdailyTesseralSP,
                    int maxOrderMdailyTesseralSP,
                    int maxEccPowMdailyTesseralSP)

Simple constructor.

Parameters:

centralBodyFrame - rotating body frame

centralBodyRotationRate - central body rotation rate (rad/s)

provider - provider for spherical harmonics

maxDegreeTesseralSP - maximal degree to consider for short periodics tesseral harmonics potential (must be between 2 and provider.getMaxDegree())

maxOrderTesseralSP - maximal order to consider for short periodics tesseral harmonics potential (must be between 0 and provider.getMaxOrder())

maxEccPowTesseralSP - maximum power of the eccentricity to use in summation over s for short periodic tesseral harmonics (without m-daily), should typically not exceed 4 as higher values will exceed computer capacity (must be between 0 and provider.getMaxOrder() though, however if order = 0 the value can be anything since it won't be used in the code)

maxFrequencyShortPeriodics - maximum frequency in mean longitude for short periodic computations (typically maxDegreeTesseralSP + maxEccPowTesseralSP and no more than 12)

maxDegreeMdailyTesseralSP - maximal degree to consider for short periodics m-daily tesseral harmonics potential (must be between 2 and provider.getMaxDegree())

maxOrderMdailyTesseralSP - maximal order to consider for short periodics m-daily tesseral harmonics potential (must be between 0 and provider.getMaxOrder())

maxEccPowMdailyTesseralSP - maximum power of the eccentricity to use in summation over s for m-daily tesseral harmonics, (must be between 0 and maxDegreeMdailyTesseralSP - 2, but should typically not exceed 4 as higher values will exceed computer capacity)

Since:

7.2

Method Detail

initializeShortPeriodTerms

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

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 for specific date (1 value only per parameter driver) obtained for example by calling ParameterDriversProvider.getParameters(AbsoluteDate) on force model.

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 for specific date (1 value only per parameter driver) obtained for example by calling ParameterDriversProvider.getParameters(AbsoluteDate) on force model or AbstractGradientConverter.getParametersAtStateDate(FieldSpacecraftState, ParameterDriversProvider) on gradient converter.

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 spacecraftState,
                                   AuxiliaryElements auxiliaryElements,
                                   double[] parameters)

Computes the mean equinoctial elements rates da_i / dt.

Specified by:

getMeanElementRate in interface DSSTForceModel

Parameters:

spacecraftState - current state information: date, kinematics, attitude

auxiliaryElements - auxiliary elements related to the current orbit

parameters - values of the force model parameters at state date (only 1 span for each parameter driver) obtained for example by calling ParameterDriversProvider.getParameters(AbsoluteDate) on force model.

Returns:

the mean element rates dai/dt

getMeanElementRate

public <T extends CalculusFieldElement<T>> T[] getMeanElementRate(FieldSpacecraftState<T> spacecraftState,
                                                                  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:

spacecraftState - current state information: date, kinematics, attitude

auxiliaryElements - auxiliary elements related to the current orbit

parameters - values of the force model parameters at state date (only 1 span for each parameter driver) obtained for example by calling ParameterDriversProvider.getParameters(Field, FieldAbsoluteDate) on force model or AbstractGradientConverter.getParametersAtStateDate(FieldSpacecraftState, ParameterDriversProvider) on gradient converter.

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 (all span values for each parameters) obtained for example by calling ParameterDriversProvider.getParametersAllValues() on force model. The extract parameter method DSSTForceModel.extractParameters(double[], AbsoluteDate) is called in the method to select the right parameter corresponding to the mean state date.

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 (all span values for each parameters) obtained for example by calling ParameterDriversProvider.getParametersAllValues(Field) on force model or AbstractGradientConverter.getParameters(FieldSpacecraftState, ParameterDriversProvider) on gradient converter. The extract parameter method DSSTForceModel.extractParameters(CalculusFieldElement[], FieldAbsoluteDate) is called in the method to select the right parameter.

meanStates - mean states information: date, kinematics, attitude

getParametersDrivers

public List<ParameterDriver> getParametersDrivers()

Get the drivers for parameters.

Specified by:

getParametersDrivers in interface ParameterDriversProvider

Returns:

drivers for parameters

registerAttitudeProvider

public void registerAttitudeProvider(AttitudeProvider attitudeProvider)

Register an attitude provider.

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

Specified by:

registerAttitudeProvider in interface DSSTForceModel

Parameters:

attitudeProvider - the AttitudeProvider