Package org.orekit.propagation.events

Class LatitudeCrossingDetector

java.lang.Object

org.orekit.propagation.events.AbstractDetector<LatitudeCrossingDetector>

org.orekit.propagation.events.LatitudeCrossingDetector

All Implemented Interfaces:

EventDetector

public class LatitudeCrossingDetector
extends AbstractDetector<LatitudeCrossingDetector>

Detector for geographic latitude crossing.

This detector identifies when a spacecraft crosses a fixed latitude with respect to a central body.

Since:

7.1

Author:

Luc Maisonobe

Field Summary

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

DEFAULT_MAX_ITER, DEFAULT_MAXCHECK, DEFAULT_THRESHOLD

Constructor Summary

Constructors

Modifier	Constructor	Description
	LatitudeCrossingDetector(double maxCheck, double threshold, OneAxisEllipsoid body, double latitude)	Build a detector.
	LatitudeCrossingDetector(OneAxisEllipsoid body, double latitude)	Build a new detector.
protected	LatitudeCrossingDetector(AdaptableInterval maxCheck, double threshold, int maxIter, EventHandler handler, OneAxisEllipsoid body, double latitude)	Protected constructor with full parameters.

Method Summary

Modifier and Type	Method	Description
protected LatitudeCrossingDetector	create(AdaptableInterval newMaxCheck, double newThreshold, int newMaxIter, EventHandler newHandler)	Build a new instance.
double	g(SpacecraftState s)	Compute the value of the detection function.
OneAxisEllipsoid	getBody()	Get the body on which the geographic zone is defined.
double	getLatitude()	Get the fixed latitude to be crossed (radians).

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

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

Methods inherited from class java.lang.Object

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

Constructor Detail

LatitudeCrossingDetector

public LatitudeCrossingDetector(OneAxisEllipsoid body,
                                double latitude)

Build a new detector.

The new instance uses default values for maximal checking interval (AbstractDetector.DEFAULT_MAXCHECK) and convergence threshold (AbstractDetector.DEFAULT_THRESHOLD).

Parameters:

body - body on which the latitude is defined

latitude - latitude to be crossed

LatitudeCrossingDetector

public LatitudeCrossingDetector(double maxCheck,
                                double threshold,
                                OneAxisEllipsoid body,
                                double latitude)

Build a detector.

Parameters:

maxCheck - maximal checking interval (s)

threshold - convergence threshold (s)

body - body on which the latitude is defined

latitude - latitude to be crossed

LatitudeCrossingDetector

protected LatitudeCrossingDetector(AdaptableInterval maxCheck,
                                   double threshold,
                                   int maxIter,
                                   EventHandler handler,
                                   OneAxisEllipsoid body,
                                   double latitude)

Protected constructor with full parameters.

This constructor is not public as users are expected to use the builder API with the various withXxx() methods to set up the instance in a readable manner without using a huge amount of parameters.

Parameters:

maxCheck - maximum checking interval

threshold - convergence threshold (s)

maxIter - maximum number of iterations in the event time search

handler - event handler to call at event occurrences

body - body on which the latitude is defined

latitude - latitude to be crossed

Method Detail

create

protected LatitudeCrossingDetector create(AdaptableInterval newMaxCheck,
                                          double newThreshold,
                                          int newMaxIter,
                                          EventHandler newHandler)

Build a new instance.

Specified by:

create in class AbstractDetector<LatitudeCrossingDetector>

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

getBody

public OneAxisEllipsoid getBody()

Get the body on which the geographic zone is defined.

Returns:

body on which the geographic zone is defined

getLatitude

public double getLatitude()

Get the fixed latitude to be crossed (radians).

Returns:

fixed latitude to be crossed (radians)

g

public double g(SpacecraftState s)

Compute the value of the detection function.

The value is the spacecraft latitude minus the fixed latitude to be crossed. It is positive if the spacecraft is northward and negative if it is southward with respect to the fixed latitude.

Specified by:

g in interface EventDetector

Specified by:

g in class AbstractDetector<LatitudeCrossingDetector>

Parameters:

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

Returns:

spacecraft latitude minus the fixed latitude to be crossed