Package org.orekit.propagation.events

Class FieldApsideDetector<T extends CalculusFieldElement<T>>

java.lang.Object

org.orekit.propagation.events.FieldAbstractDetector<FieldApsideDetector<T>,T>

org.orekit.propagation.events.FieldApsideDetector<T>

Type Parameters:

T - type of the field elements

All Implemented Interfaces:

FieldEventDetector<T>

public class FieldApsideDetector<T extends CalculusFieldElement<T>>
extends FieldAbstractDetector<FieldApsideDetector<T>,T>

Finder for apside crossing events.

This class finds apside crossing events (i.e. apogee or perigee crossing).

The default implementation behavior is to continue propagation at apogee crossing and to stop propagation at perigee crossing. This can be changed by calling FieldAbstractDetector.withHandler(FieldEventHandler) after construction.

Beware that apside detection will fail for almost circular orbits. If for example an apside detector is used to trigger an ImpulseManeuver and the maneuver change the orbit shape to circular, then the detector may completely fail just after the maneuver has been performed!

Author:

Luc Maisonobe

See Also:

• FieldPropagator.addEventDetector(FieldEventDetector)

Field Summary

Fields inherited from class org.orekit.propagation.events.FieldAbstractDetector

DEFAULT_MAX_CHECK, DEFAULT_MAX_ITER, DEFAULT_THRESHOLD

Constructor Summary

Constructors

Modifier	Constructor	Description
	FieldApsideDetector(FieldOrbit<T> orbit)	Build a new instance.
	FieldApsideDetector(FieldEventDetectionSettings<T> detectionSettings, FieldEventHandler<T> handler)	Constructor.
protected	FieldApsideDetector(ApsideEventFunction apsideEventFunction, FieldEventDetectionSettings<T> detectionSettings, FieldEventHandler<T> handler)	Constructor with full parameters.
	FieldApsideDetector(T keplerianPeriod)	Build a new instance.
	FieldApsideDetector(T threshold, FieldOrbit<T> orbit)	Build a new instance.

Method Summary

Modifier and Type	Method	Description
protected FieldApsideDetector<T>	create(FieldEventDetectionSettings<T> detectionSettings, FieldEventHandler<T> newHandler)	Build a new instance.
T	g(FieldSpacecraftState<T> s)	Compute the value of the switching function.
ApsideDetector	toEventDetector(EventHandler eventHandler)	Build non-Field instance.

Methods inherited from class org.orekit.propagation.events.FieldAbstractDetector

checkIfForward, getDetectionSettings, getEventFunction, getHandler, init, isForward, withDetectionSettings, withHandler, withMaxCheck, withMaxCheck, withMaxIter, withThreshold

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.events.FieldEventDetector

finish, getMaxCheckInterval, getMaxIterationCount, getThreshold, reset

Constructor Details

FieldApsideDetector

public FieldApsideDetector(T keplerianPeriod)

Build a new instance.

The Keplerian period is used only to set an upper bound for the max check interval to period/3 and to set the convergence threshold.

Parameters:

keplerianPeriod - estimate of the Keplerian period

Since:

12.1

FieldApsideDetector

public FieldApsideDetector(FieldOrbit<T> orbit)

Build a new instance.

The orbit is used only to set an upper bound for the max check interval to period/3 and to set the convergence threshold according to orbit size

Parameters:

orbit - initial orbit

FieldApsideDetector

public FieldApsideDetector(T threshold,
 FieldOrbit<T> orbit)

Build a new instance.

The orbit is used only to set an upper bound for the max check interval to period/3

Parameters:

threshold - convergence threshold (s)

orbit - initial orbit

FieldApsideDetector

public FieldApsideDetector(FieldEventDetectionSettings<T> detectionSettings,
 FieldEventHandler<T> handler)

Constructor.

This constructor is public because otherwise all accessible ones would require an orbit.

Parameters:

detectionSettings - event detection settings

handler - event handler to call at event occurrences

Since:

13.0

FieldApsideDetector

protected FieldApsideDetector(ApsideEventFunction apsideEventFunction,
 FieldEventDetectionSettings<T> detectionSettings,
 FieldEventHandler<T> handler)

Constructor with full parameters.

Parameters:

apsideEventFunction - event function

detectionSettings - event detection settings

handler - event handler to call at event occurrences

Since:

14.0

Method Details

create

protected FieldApsideDetector<T> create(FieldEventDetectionSettings<T> detectionSettings,
 FieldEventHandler<T> newHandler)

Build a new instance.

Specified by:

create in class FieldAbstractDetector<FieldApsideDetector<T extends CalculusFieldElement<T>>,T extends CalculusFieldElement<T>>

Parameters:

detectionSettings - detection settings

newHandler - event handler to call at event occurrences

Returns:

a new instance of the appropriate sub-type

g

public T g(FieldSpacecraftState<T> s)

Compute the value of the switching function. This function computes the dot product of the 2 vectors : position.velocity.

Parameters:

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

Returns:

value of the switching function

toEventDetector

public ApsideDetector toEventDetector(EventHandler eventHandler)

Build non-Field instance.

Overrides:

toEventDetector in class FieldAbstractDetector<FieldApsideDetector<T extends CalculusFieldElement<T>>,T extends CalculusFieldElement<T>>

Parameters:

eventHandler - event handler

Returns:

event detector