Package org.orekit.propagation.events

Class FieldAltitudeDetector<T extends org.hipparchus.RealFieldElement<T>>

java.lang.Object

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

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

All Implemented Interfaces:

FieldEventDetector<T>

public class FieldAltitudeDetector<T extends org.hipparchus.RealFieldElement<T>>
extends FieldAbstractDetector<FieldAltitudeDetector<T>,T>

Finder for satellite altitude crossing events.

This class finds altitude events (i.e. satellite crossing a predefined altitude level above ground).

The default implementation behavior is to continue propagation when ascending and to stop propagation when descending. This can be changed by calling FieldAbstractDetector.withHandler(FieldEventHandler) after construction.

Since:

9.0

Author:

Luc Maisonobe

See Also:

FieldPropagator.addEventDetector(FieldEventDetector)

Field Summary

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

DEFAULT_MAX_ITER, DEFAULT_MAXCHECK, DEFAULT_THRESHOLD

Constructor Summary

Constructors

Constructor	Description
FieldAltitudeDetector(T altitude, BodyShape bodyShape)	Build a new altitude detector.
FieldAltitudeDetector(T maxCheck, T altitude, BodyShape bodyShape)	Build a new altitude detector.
FieldAltitudeDetector(T maxCheck, T threshold, T altitude, BodyShape bodyShape)	Build a new altitude detector.

Method Summary

Modifier and Type	Method	Description
protected FieldAltitudeDetector<T>	create(T newMaxCheck, T newThreshold, int newMaxIter, FieldEventHandler<? super FieldAltitudeDetector<T>,T> newHandler)	Build a new instance.
T	g(FieldSpacecraftState<T> s)	Compute the value of the switching function.
T	getAltitude()	Get the threshold altitude value.
BodyShape	getBodyShape()	Get the body shape.

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

eventOccurred, getHandler, getMaxCheckInterval, getMaxIterationCount, getThreshold, init, isForward, resetState, withHandler, withMaxCheck, withMaxIter, withThreshold

Methods inherited from class java.lang.Object

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

Constructor Detail

FieldAltitudeDetector

public FieldAltitudeDetector(T altitude,
                             BodyShape bodyShape)

Build a new altitude detector.

This simple constructor takes default values for maximal checking interval (FieldAbstractDetector.DEFAULT_MAXCHECK) and convergence threshold (FieldAbstractDetector.DEFAULT_THRESHOLD).

Parameters:

altitude - threshold altitude value

bodyShape - body shape with respect to which altitude should be evaluated

FieldAltitudeDetector

public FieldAltitudeDetector(T maxCheck,
                             T altitude,
                             BodyShape bodyShape)

Build a new altitude detector.

This simple constructor takes default value for convergence threshold (FieldAbstractDetector.DEFAULT_THRESHOLD).

The maximal interval between altitude checks should be smaller than the half duration of the minimal pass to handle, otherwise some short passes could be missed.

Parameters:

maxCheck - maximal checking interval (s)

altitude - threshold altitude value (m)

bodyShape - body shape with respect to which altitude should be evaluated

FieldAltitudeDetector

public FieldAltitudeDetector(T maxCheck,
                             T threshold,
                             T altitude,
                             BodyShape bodyShape)

Build a new altitude detector.

The maximal interval between altitude checks should be smaller than the half duration of the minimal pass to handle, otherwise some short passes could be missed.

The maximal interval between altitude checks should be smaller than the half duration of the minimal pass to handle, otherwise some short passes could be missed.

Parameters:

maxCheck - maximal checking interval (s)

threshold - convergence threshold (s)

altitude - threshold altitude value (m)

bodyShape - body shape with respect to which altitude should be evaluated

Method Detail

create

protected FieldAltitudeDetector<T> create(T newMaxCheck,
                                          T newThreshold,
                                          int newMaxIter,
                                          FieldEventHandler<? super FieldAltitudeDetector<T>,T> newHandler)

Build a new instance.

Specified by:

create in class FieldAbstractDetector<FieldAltitudeDetector<T extends org.hipparchus.RealFieldElement<T>>,T extends org.hipparchus.RealFieldElement<T>>

Parameters:

newMaxCheck - maximum checking interval (s)

newThreshold - convergence threshold (s)

newMaxIter - maximum number of iterations in the event time search

newHandler - event handler to call at event occurrences

Returns:

a new instance of the appropriate sub-type

getAltitude

public T getAltitude()

Get the threshold altitude value.

Returns:

the threshold altitude value (m)

getBodyShape

public BodyShape getBodyShape()

Get the body shape.

Returns:

the body shape

g

public T g(FieldSpacecraftState<T> s)

Compute the value of the switching function. This function measures the difference between the current altitude and the threshold altitude.

Specified by:

g in interface FieldEventDetector<T extends org.hipparchus.RealFieldElement<T>>

Specified by:

g in class FieldAbstractDetector<FieldAltitudeDetector<T extends org.hipparchus.RealFieldElement<T>>,T extends org.hipparchus.RealFieldElement<T>>

Parameters:

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

Returns:

value of the switching function