FieldDSSTPropagator (ORbit Extrapolation KIT 10.2 API)

java.lang.Object
- org.orekit.propagation.FieldAbstractPropagator<T>
- - org.orekit.propagation.integration.FieldAbstractIntegratedPropagator<T>
  - - org.orekit.propagation.semianalytical.dsst.FieldDSSTPropagator<T>

All Implemented Interfaces:

FieldPropagator<T>, FieldPVCoordinatesProvider<T>
```
public class FieldDSSTPropagator<T extends RealFieldElement<T>>
extends FieldAbstractIntegratedPropagator<T>
```
This class propagates orbits using the DSST theory.
Whereas analytical propagators are configured only thanks to their various constructors and can be used immediately after construction, such a semianalytical propagator configuration involves setting several parameters between construction time and propagation time, just as numerical propagators.

The configuration parameters that can be set are:
- the initial spacecraft state (setInitialState(FieldSpacecraftState))
- the various force models (addForceModel(DSSTForceModel), removeForceModels())
- the discrete events that should be triggered during propagation ( FieldAbstractIntegratedPropagator.addEventDetector(org.orekit.propagation.events.FieldEventDetector), FieldAbstractIntegratedPropagator.clearEventsDetectors())
- the binding logic with the rest of the application (FieldAbstractIntegratedPropagator.setSlaveMode(), FieldAbstractPropagator.setMasterMode(RealFieldElement, org.orekit.propagation.sampling.FieldOrekitFixedStepHandler), FieldAbstractIntegratedPropagator.setMasterMode(org.orekit.propagation.sampling.FieldOrekitStepHandler), FieldAbstractIntegratedPropagator.setEphemerisMode(), FieldAbstractIntegratedPropagator.getGeneratedEphemeris())
From these configuration parameters, only the initial state is mandatory. The default propagation settings are in equinoctial parameters with true longitude argument. The central attraction coefficient used to define the initial orbit will be used. However, specifying only the initial state would mean the propagator would use only Keplerian forces. In this case, the simpler KeplerianPropagator class would be more effective.

The underlying numerical integrator set up in the constructor may also have its own configuration parameters. Typical configuration parameters for adaptive stepsize integrators are the min, max and perhaps start step size as well as the absolute and/or relative errors thresholds.

The state that is seen by the integrator is a simple six elements double array. These six elements are:
- the equinoctial orbit parameters (a, e_x, e_y, h_x, h_y, λ_m) in meters and radians,
By default, at the end of the propagation, the propagator resets the initial state to the final state, thus allowing a new propagation to be started from there without recomputing the part already performed. This behaviour can be chenged by calling FieldAbstractIntegratedPropagator.setResetAtEnd(boolean).

Beware the same instance cannot be used simultaneously by different threads, the class is not thread-safe.
Since:

10.0

Author:

Romain Di Costanzo, Pascal Parraud

See Also:

FieldSpacecraftState, DSSTForceModel

Nested Class Summary
- Nested classes/interfaces inherited from class org.orekit.propagation.integration.FieldAbstractIntegratedPropagator
  FieldAbstractIntegratedPropagator.MainStateEquations<T extends RealFieldElement<T>>

Field Summary
- Fields inherited from interface org.orekit.propagation.FieldPropagator
  DEFAULT_LAW, DEFAULT_MASS, EPHEMERIS_GENERATION_MODE, MASTER_MODE, SLAVE_MODE

Constructor Summary

Constructors
Constructor and Description
`FieldDSSTPropagator(Field<T> field, FieldODEIntegrator<T> integrator)` Create a new instance of DSSTPropagator.
`FieldDSSTPropagator(Field<T> field, FieldODEIntegrator<T> integrator, AttitudeProvider attitudeProvider)` Create a new instance of DSSTPropagator.
`FieldDSSTPropagator(Field<T> field, FieldODEIntegrator<T> integrator, PropagationType propagationType)` Create a new instance of DSSTPropagator.
`FieldDSSTPropagator(Field<T> field, FieldODEIntegrator<T> integrator, PropagationType propagationType, AttitudeProvider attitudeProvider)` Create a new instance of DSSTPropagator.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addForceModel(DSSTForceModel force)` Add a force model to the global perturbation model.
`protected void`	`afterIntegration()` Method called just after integration.
`protected void`	`beforeIntegration(FieldSpacecraftState<T> initialState, FieldAbsoluteDate<T> tEnd)` Method called just before integration.
`FieldSpacecraftState<T>`	`computeMeanState(FieldSpacecraftState<T> osculating, AttitudeProvider attitudeProvider, Collection<DSSTForceModel> forceModel)` Conversion from osculating to mean orbit.
`FieldSpacecraftState<T>`	`computeMeanState(FieldSpacecraftState<T> osculating, AttitudeProvider attitudeProvider, Collection<DSSTForceModel> forceModel, double epsilon, int maxIterations)` Conversion from osculating to mean orbit.
`FieldSpacecraftState<T>`	`computeOsculatingState(FieldSpacecraftState<T> mean, AttitudeProvider attitudeProvider, Collection<DSSTForceModel> forces)` Conversion from mean to osculating orbit.
`protected FieldStateMapper<T>`	`createMapper(FieldAbsoluteDate<T> referenceDate, T mu, OrbitType ignoredOrbitType, PositionAngle ignoredPositionAngleType, AttitudeProvider attitudeProvider, Frame frame)` Create a mapper between raw double components and spacecraft state.
`List<DSSTForceModel>`	`getAllForceModels()` Get all the force models, perturbing forces and Newtonian attraction included.
`protected FieldSpacecraftState<T>`	`getInitialIntegrationState()` Get the initial state for integration.
`protected FieldAbstractIntegratedPropagator.MainStateEquations<T>`	`getMainStateEquations(FieldODEIntegrator<T> integrator)` Get the differential equations to integrate (for main state only).
`OrbitType`	`getOrbitType()` Get propagation parameter type.
`PositionAngle`	`getPositionAngleType()` Get propagation parameter type.
`int`	`getSatelliteRevolution()` Get the number of satellite revolutions to use for converting osculating to mean elements.
`Set<String>`	`getSelectedCoefficients()` Get the selected short periodic coefficients that must be stored as additional states.
`boolean`	`initialIsOsculating()` Check if the initial state is provided in osculating elements.
`void`	`removeForceModels()` Remove all perturbing force models from the global perturbation model (except central attraction).
`void`	`resetInitialState(FieldSpacecraftState<T> state)` Reset the initial state.
`void`	`setAttitudeProvider(AttitudeProvider attitudeProvider)` Set attitude provider.
`void`	`setInitialState(FieldSpacecraftState<T> initialState)` Set the initial state with osculating orbital elements.
`void`	`setInitialState(FieldSpacecraftState<T> initialState, PropagationType stateType)` Set the initial state.
`void`	`setInterpolationGridToFixedNumberOfPoints(int interpolationPoints)` Set the interpolation grid generator.
`void`	`setInterpolationGridToMaxTimeGap(T maxGap)` Set the interpolation grid generator.
`void`	`setMu(T mu)` Set the central attraction coefficient μ.
`void`	`setSatelliteRevolution(int satelliteRevolution)` Override the default value of the parameter.
`void`	`setSelectedCoefficients(Set<String> selectedCoefficients)` Set the selected short periodic coefficients that must be stored as additional states.
`static <T extends RealFieldElement<T>> double[][]`	`tolerances(T dP, FieldOrbit<T> orbit)` Estimate tolerance vectors for an AdaptativeStepsizeIntegrator.

Methods inherited from class org.orekit.propagation.integration.FieldAbstractIntegratedPropagator
addAdditionalEquations, addEventDetector, clearEventsDetectors, getBasicDimension, getCalls, getEventsDetectors, getGeneratedEphemeris, getIntegrator, getManagedAdditionalStates, getMu, initMapper, isAdditionalStateManaged, isMeanOrbit, propagate, propagate, propagate, setEphemerisMode, setMasterMode, setOrbitType, setPositionAngleType, setResetAtEnd, setSlaveMode, setUpEventDetector, setUpUserEventDetectors

Methods inherited from class org.orekit.propagation.FieldAbstractPropagator
addAdditionalStateProvider, getAdditionalStateProviders, getAttitudeProvider, getField, getFixedStepSize, getFrame, getInitialState, getMode, getPVCoordinates, getStartDate, getStepHandler, initializePropagation, setMasterMode, setStartDate, stateChanged, updateAdditionalStates

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - FieldDSSTPropagator
```
@DefaultDataContext
public FieldDSSTPropagator(Field<T> field,
                                               FieldODEIntegrator<T> integrator,
                                               PropagationType propagationType)
```
    Create a new instance of DSSTPropagator.
    After creation, there are no perturbing forces at all. This means that if addForceModel is not called after creation, the integrated orbit will follow a Keplerian evolution only.
    
    This constructor uses the default data context.
    
    Parameters:
    
    field - field used by default
    
    integrator - numerical integrator to use for propagation.
    
    propagationType - type of orbit to output (mean or osculating).
    
    See Also:
    
    FieldDSSTPropagator(Field, FieldODEIntegrator, PropagationType, AttitudeProvider)
  - FieldDSSTPropagator
```
public FieldDSSTPropagator(Field<T> field,
                           FieldODEIntegrator<T> integrator,
                           PropagationType propagationType,
                           AttitudeProvider attitudeProvider)
```
    Create a new instance of DSSTPropagator.
    After creation, there are no perturbing forces at all. This means that if addForceModel is not called after creation, the integrated orbit will follow a Keplerian evolution only.
    
    Parameters:
    
    field - field used by default
    
    integrator - numerical integrator to use for propagation.
    
    propagationType - type of orbit to output (mean or osculating).
    
    attitudeProvider - attitude law to use.
    
    Since:
    
    10.1
  - FieldDSSTPropagator
```
@DefaultDataContext
public FieldDSSTPropagator(Field<T> field,
                                               FieldODEIntegrator<T> integrator)
```
    Create a new instance of DSSTPropagator.
    After creation, there are no perturbing forces at all. This means that if addForceModel is not called after creation, the integrated orbit will follow a Keplerian evolution only. Only the mean orbits will be generated.
    
    This constructor uses the default data context.
    
    Parameters:
    
    field - fied used by default
    
    integrator - numerical integrator to use for propagation.
    
    See Also:
    
    FieldDSSTPropagator(Field, FieldODEIntegrator, AttitudeProvider)
  - FieldDSSTPropagator
```
public FieldDSSTPropagator(Field<T> field,
                           FieldODEIntegrator<T> integrator,
                           AttitudeProvider attitudeProvider)
```
    Create a new instance of DSSTPropagator.
    After creation, there are no perturbing forces at all. This means that if addForceModel is not called after creation, the integrated orbit will follow a Keplerian evolution only. Only the mean orbits will be generated.
    
    Parameters:
    
    field - fied used by default
    
    integrator - numerical integrator to use for propagation.
    
    attitudeProvider - attitude law to use.
    
    Since:
    
    10.1
- Method Detail
  - setMu
```
public void setMu(T mu)
```
    Set the central attraction coefficient μ.
    Setting the central attraction coefficient is equivalent to add a DSSTNewtonianAttraction force model.
    
    Overrides:
    
    setMu in class FieldAbstractIntegratedPropagator<T extends RealFieldElement<T>>
    
    Parameters:
    
    mu - central attraction coefficient (m³/s²)
    
    See Also:
    
    addForceModel(DSSTForceModel), getAllForceModels()
  - setInitialState
```
public void setInitialState(FieldSpacecraftState<T> initialState)
```
    Set the initial state with osculating orbital elements.
    
    Parameters:
    
    initialState - initial state (defined with osculating elements)
  - setInitialState
```
public void setInitialState(FieldSpacecraftState<T> initialState,
                            PropagationType stateType)
```
    Set the initial state.
    
    Parameters:
    
    initialState - initial state
    
    stateType - defined if the orbital state is defined with osculating or mean elements
  - resetInitialState
```
public void resetInitialState(FieldSpacecraftState<T> state)
```
    Reset the initial state.
    
    Specified by:
    
    resetInitialState in interface FieldPropagator<T extends RealFieldElement<T>>
    
    Overrides:
    
    resetInitialState in class FieldAbstractPropagator<T extends RealFieldElement<T>>
    
    Parameters:
    
    state - new initial state
  - setSelectedCoefficients
```
public void setSelectedCoefficients(Set<String> selectedCoefficients)
```
    Set the selected short periodic coefficients that must be stored as additional states.
    
    Parameters:
    
    selectedCoefficients - short periodic coefficients that must be stored as additional states (null means no coefficients are selected, empty set means all coefficients are selected)
  - getSelectedCoefficients
```
public Set<String> getSelectedCoefficients()
```
    Get the selected short periodic coefficients that must be stored as additional states.
    
    Returns:
    
    short periodic coefficients that must be stored as additional states (null means no coefficients are selected, empty set means all coefficients are selected)
  - initialIsOsculating
```
public boolean initialIsOsculating()
```
    Check if the initial state is provided in osculating elements.
    
    Returns:
    
    true if initial state is provided in osculating elements
  - setInterpolationGridToFixedNumberOfPoints
```
public void setInterpolationGridToFixedNumberOfPoints(int interpolationPoints)
```
    Set the interpolation grid generator.
    The generator will create an interpolation grid with a fixed number of points for each mean element integration step.
    
    If neither setInterpolationGridToFixedNumberOfPoints(int) nor setInterpolationGridToMaxTimeGap(RealFieldElement) has been called, by default the propagator is set as to 3 interpolations points per step.
    
    Parameters:
    
    interpolationPoints - number of interpolation points at each integration step
    
    Since:
    
    7.1
    
    See Also:
    
    setInterpolationGridToMaxTimeGap(RealFieldElement)
  - setInterpolationGridToMaxTimeGap
```
public void setInterpolationGridToMaxTimeGap(T maxGap)
```
    Set the interpolation grid generator.
    The generator will create an interpolation grid with a maximum time gap between interpolation points.
    
    If neither setInterpolationGridToFixedNumberOfPoints(int) nor setInterpolationGridToMaxTimeGap(RealFieldElement) has been called, by default the propagator is set as to 3 interpolations points per step.
    
    Parameters:
    
    maxGap - maximum time gap between interpolation points (seconds)
    
    Since:
    
    7.1
    
    See Also:
    
    setInterpolationGridToFixedNumberOfPoints(int)
  - addForceModel
```
public void addForceModel(DSSTForceModel force)
```
    Add a force model to the global perturbation model.
    If this method is not called at all, the integrated orbit will follow a Keplerian evolution only.
    
    Parameters:
    
    force - perturbing force to add
    
    See Also:
    
    removeForceModels(), setMu(RealFieldElement)
  - removeForceModels
```
public void removeForceModels()
```
    Remove all perturbing force models from the global perturbation model (except central attraction).
    Once all perturbing forces have been removed (and as long as no new force model is added), the integrated orbit will follow a Keplerian evolution only.
    
    See Also:
    
    addForceModel(DSSTForceModel)
  - getAllForceModels
```
public List<DSSTForceModel> getAllForceModels()
```
    Get all the force models, perturbing forces and Newtonian attraction included.
    
    Returns:
    
    list of perturbing force models, with Newtonian attraction being the last one
    
    See Also:
    
    addForceModel(DSSTForceModel), setMu(RealFieldElement)
  - getOrbitType
```
public OrbitType getOrbitType()
```
    Get propagation parameter type.
    
    Overrides:
    
    getOrbitType in class FieldAbstractIntegratedPropagator<T extends RealFieldElement<T>>
    
    Returns:
    
    orbit type used for propagation
  - getPositionAngleType
```
public PositionAngle getPositionAngleType()
```
    Get propagation parameter type.
    
    Overrides:
    
    getPositionAngleType in class FieldAbstractIntegratedPropagator<T extends RealFieldElement<T>>
    
    Returns:
    
    angle type to use for propagation
  - computeOsculatingState
```
public FieldSpacecraftState<T> computeOsculatingState(FieldSpacecraftState<T> mean,
                                                      AttitudeProvider attitudeProvider,
                                                      Collection<DSSTForceModel> forces)
```
    Conversion from mean to osculating orbit.
    Compute osculating state in a DSST sense, corresponding to the mean SpacecraftState in input, and according to the Force models taken into account.
    Since the osculating state is obtained by adding short-periodic variation of each force model, the resulting output will depend on the force models parameterized in input.
    
    Parameters:
    
    mean - Mean state to convert
    
    forces - Forces to take into account
    
    attitudeProvider - attitude provider (may be null if there are no Gaussian force models like atmospheric drag, radiation pressure or specific user-defined models)
    
    Returns:
    
    osculating state in a DSST sense
  - computeMeanState
```
public FieldSpacecraftState<T> computeMeanState(FieldSpacecraftState<T> osculating,
                                                AttitudeProvider attitudeProvider,
                                                Collection<DSSTForceModel> forceModel)
```
    Conversion from osculating to mean orbit.
    Compute mean state in a DSST sense, corresponding to the osculating SpacecraftState in input, and according to the Force models taken into account.
    Since the osculating state is obtained with the computation of short-periodic variation of each force model, the resulting output will depend on the force models parameterized in input.
    The computation is done through a fixed-point iteration process.
    
    Parameters:
    
    osculating - Osculating state to convert
    
    attitudeProvider - attitude provider (may be null if there are no Gaussian force models like atmospheric drag, radiation pressure or specific user-defined models)
    
    forceModel - Forces to take into account
    
    Returns:
    
    mean state in a DSST sense
  - computeMeanState
```
public FieldSpacecraftState<T> computeMeanState(FieldSpacecraftState<T> osculating,
                                                AttitudeProvider attitudeProvider,
                                                Collection<DSSTForceModel> forceModel,
                                                double epsilon,
                                                int maxIterations)
```
    Conversion from osculating to mean orbit.
    Compute mean state in a DSST sense, corresponding to the osculating SpacecraftState in input, and according to the Force models taken into account.
    Since the osculating state is obtained with the computation of short-periodic variation of each force model, the resulting output will depend on the force models parameterized in input.
    The computation is done through a fixed-point iteration process.
    
    Parameters:
    
    osculating - Osculating state to convert
    
    attitudeProvider - attitude provider (may be null if there are no Gaussian force models like atmospheric drag, radiation pressure or specific user-defined models)
    
    forceModel - Forces to take into account
    
    epsilon - convergence threshold for mean parameters conversion
    
    maxIterations - maximum iterations for mean parameters conversion
    
    Returns:
    
    mean state in a DSST sense
    
    Since:
    
    10.1
  - setSatelliteRevolution
```
public void setSatelliteRevolution(int satelliteRevolution)
```
    Override the default value of the parameter.
    By default, if the initial orbit is defined as osculating, it will be averaged over 2 satellite revolutions. This can be changed by using this method.
    
    Parameters:
    
    satelliteRevolution - number of satellite revolutions to use for converting osculating to mean elements
  - getSatelliteRevolution
```
public int getSatelliteRevolution()
```
    Get the number of satellite revolutions to use for converting osculating to mean elements.
    
    Returns:
    
    number of satellite revolutions to use for converting osculating to mean elements
  - setAttitudeProvider
```
public void setAttitudeProvider(AttitudeProvider attitudeProvider)
```
    Set attitude provider.
    
    Specified by:
    
    setAttitudeProvider in interface FieldPropagator<T extends RealFieldElement<T>>
    
    Overrides:
    
    setAttitudeProvider in class FieldAbstractIntegratedPropagator<T extends RealFieldElement<T>>
    
    Parameters:
    
    attitudeProvider - attitude provider
  - beforeIntegration
```
protected void beforeIntegration(FieldSpacecraftState<T> initialState,
                                 FieldAbsoluteDate<T> tEnd)
```
    Method called just before integration.
    The default implementation does nothing, it may be specialized in subclasses.
    
    Overrides:
    
    beforeIntegration in class FieldAbstractIntegratedPropagator<T extends RealFieldElement<T>>
    
    Parameters:
    
    initialState - initial state
    
    tEnd - target date at which state should be propagated
  - afterIntegration
```
protected void afterIntegration()
```
    Method called just after integration.
    The default implementation does nothing, it may be specialized in subclasses.
    
    Overrides:
    
    afterIntegration in class FieldAbstractIntegratedPropagator<T extends RealFieldElement<T>>
  - getInitialIntegrationState
```
protected FieldSpacecraftState<T> getInitialIntegrationState()
```
    Get the initial state for integration.
    
    Overrides:
    
    getInitialIntegrationState in class FieldAbstractIntegratedPropagator<T extends RealFieldElement<T>>
    
    Returns:
    
    initial state for integration
  - createMapper
```
protected FieldStateMapper<T> createMapper(FieldAbsoluteDate<T> referenceDate,
                                           T mu,
                                           OrbitType ignoredOrbitType,
                                           PositionAngle ignoredPositionAngleType,
                                           AttitudeProvider attitudeProvider,
                                           Frame frame)
```
    Create a mapper between raw double components and spacecraft state. /** Simple constructor.
    The position parameter type is meaningful only if propagation orbit type support it. As an example, it is not meaningful for propagation in Cartesian parameters.
    
    Note that for DSST, orbit type is hardcoded to OrbitType.EQUINOCTIAL and position angle type is hardcoded to PositionAngle.MEAN, so the corresponding parameters are ignored.
    
    Specified by:
    
    createMapper in class FieldAbstractIntegratedPropagator<T extends RealFieldElement<T>>
    
    Parameters:
    
    referenceDate - reference date
    
    mu - central attraction coefficient (m³/s²)
    
    ignoredOrbitType - orbit type to use for mapping
    
    ignoredPositionAngleType - angle type to use for propagation
    
    attitudeProvider - attitude provider
    
    frame - inertial frame
    
    Returns:
    
    new mapper
  - getMainStateEquations
```
protected FieldAbstractIntegratedPropagator.MainStateEquations<T> getMainStateEquations(FieldODEIntegrator<T> integrator)
```
    Get the differential equations to integrate (for main state only).
    
    Specified by:
    
    getMainStateEquations in class FieldAbstractIntegratedPropagator<T extends RealFieldElement<T>>
    
    Parameters:
    
    integrator - numerical integrator to use for propagation.
    
    Returns:
    
    differential equations for main state
  - tolerances
```
public static <T extends RealFieldElement<T>> double[][] tolerances(T dP,
                                                                    FieldOrbit<T> orbit)
```
    Estimate tolerance vectors for an AdaptativeStepsizeIntegrator.
    The errors are estimated from partial derivatives properties of orbits, starting from a scalar position error specified by the user. Considering the energy conservation equation V = sqrt(mu (2/r - 1/a)), we get at constant energy (i.e. on a Keplerian trajectory):
```
  V² r |dV| = mu |dr|
  
```
    So we deduce a scalar velocity error consistent with the position error. From here, we apply orbits Jacobians matrices to get consistent errors on orbital parameters.
    The tolerances are only orders of magnitude, and integrator tolerances are only local estimates, not global ones. So some care must be taken when using these tolerances. Setting 1mm as a position error does NOT mean the tolerances will guarantee a 1mm error position after several orbits integration.
    Type Parameters:
    
    T - elements type
    
    Parameters:
    
    dP - user specified position error (m)
    
    orbit - reference orbit
    
    Returns:
    
    a two rows array, row 0 being the absolute tolerance error and row 1 being the relative tolerance error

Class FieldDSSTPropagator<T extends RealFieldElement<T>>

Nested Class Summary

Nested classes/interfaces inherited from class org.orekit.propagation.integration.FieldAbstractIntegratedPropagator

Field Summary

Fields inherited from interface org.orekit.propagation.FieldPropagator

Constructor Summary

Method Summary

Methods inherited from class org.orekit.propagation.integration.FieldAbstractIntegratedPropagator

Methods inherited from class org.orekit.propagation.FieldAbstractPropagator

Methods inherited from class java.lang.Object

Constructor Detail

FieldDSSTPropagator

FieldDSSTPropagator

FieldDSSTPropagator

FieldDSSTPropagator

Method Detail

setMu

setInitialState

setInitialState

resetInitialState

setSelectedCoefficients

getSelectedCoefficients

initialIsOsculating

setInterpolationGridToFixedNumberOfPoints

setInterpolationGridToMaxTimeGap

addForceModel

removeForceModels

getAllForceModels

getOrbitType

getPositionAngleType

computeOsculatingState

computeMeanState

computeMeanState

setSatelliteRevolution

getSatelliteRevolution

setAttitudeProvider

beforeIntegration

afterIntegration

getInitialIntegrationState

createMapper

getMainStateEquations

tolerances