org.orekit.propagation.events
Class NadirSolarIncidenceDetector

java.lang.Object
  org.orekit.propagation.events.AbstractDetector
      org.orekit.propagation.events.NadirSolarIncidenceDetector

All Implemented Interfaces:

Serializable, EventDetector

public class NadirSolarIncidenceDetector
extends AbstractDetector

Spacecraft's nadir point solar incidence detector.

The solar incidence is the angle between the nadir-satellite vector and the nadir-sun vector.
This detector does not discriminate among increasing g events and decreasing g events: every detected event is a solar incidence crossing event.
The default implementation is to stop propagation when the reference solar incidence is reached. This can be changed by using provided constructors.

Since:

1.1

Version:

$Id: NadirSolarIncidenceDetector.java 14677 2015-11-25 14:52:39Z rodrigues $

Author:

Thomas Trapier

See Also:

EventDetector, Serialized Form

Concurrency :

thread-hostile

Concurrency comment :

the earth celestial body is thread hostile itself.

Nested Class Summary

Nested classes/interfaces inherited from interface org.orekit.propagation.events.EventDetector

EventDetector.Action

Field Summary

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

DEFAULT_MAXCHECK, DEFAULT_THRESHOLD

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

DECREASING, INCREASING, INCREASING_DECREASING

Constructor Summary

NadirSolarIncidenceDetector(double incidence, BodyShape earth, double maxCheck, double threshold)
Constructor for the nadir point solar incidence detector

NadirSolarIncidenceDetector(double incidence, BodyShape earth, double maxCheck, double threshold, EventDetector.Action action)
Constructor for the nadir point solar incidence detector

NadirSolarIncidenceDetector(double incidence, BodyShape earth, double maxCheck, double threshold, EventDetector.Action action, boolean remove)
Constructor for the nadir point solar incidence detector

Method Summary

EventDetector.Action	eventOccurred(SpacecraftState s, boolean increasing, boolean forward) Handle a solar incidence event and choose what to do next.
double	g(SpacecraftState s) Compute the value of the switching function.
BodyShape	getEarthShape() Returns Earth shape.
double	getIncidence() Returns incidence.
PVCoordinatesProvider	getSun() Returns Sun.
void	init(SpacecraftState s0, AbsoluteDate t) Initialize event handler at the start of a propagation.
void	setSun(PVCoordinatesProvider sun) Sets the sun PVCoordinatesProvider
boolean	shouldBeRemoved() This method is called after EventDetector.eventOccurred(org.orekit.propagation.SpacecraftState, boolean, boolean) has been triggered.

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

getMaxCheckInterval, getMaxIterationCount, getSlopeSelection, getThreshold, resetState

Methods inherited from class java.lang.Object

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

Constructor Detail

NadirSolarIncidenceDetector

public NadirSolarIncidenceDetector(double incidence,
                                   BodyShape earth,
                                   double maxCheck,
                                   double threshold)
                            throws OrekitException

Constructor for the nadir point solar incidence detector

The default implementation behavior is to stop propagation when the local time is reached.

Parameters:

incidence - the incidence to detect (set 0. to detect the terminator)

earth - the earth shape

maxCheck - maximum check (see AbstractDetector)

threshold - threshold (see AbstractDetector)

Throws:

OrekitException - error when loading the ephemeris files

NadirSolarIncidenceDetector

public NadirSolarIncidenceDetector(double incidence,
                                   BodyShape earth,
                                   double maxCheck,
                                   double threshold,
                                   EventDetector.Action action)
                            throws OrekitException

Constructor for the nadir point solar incidence detector

Parameters:

incidence - the incidence to detect (set 0. to detect the terminator)

earth - the earth shape

maxCheck - maximum check (see AbstractDetector)

threshold - threshold (see AbstractDetector)

action - action performed at nadir point solar incidence detection

Throws:

OrekitException - error when loading the ephemeris files

NadirSolarIncidenceDetector

public NadirSolarIncidenceDetector(double incidence,
                                   BodyShape earth,
                                   double maxCheck,
                                   double threshold,
                                   EventDetector.Action action,
                                   boolean remove)
                            throws OrekitException

Constructor for the nadir point solar incidence detector

Parameters:

incidence - the incidence to detect (set 0. to detect the terminator)

earth - the earth shape

maxCheck - maximum check (see AbstractDetector)

threshold - threshold (see AbstractDetector)

action - action performed at nadir point solar incidence detection

remove - true if detector should be removed at nadir point solar incidence detection

Throws:

OrekitException - error when loading the ephemeris files

Since:

3.1

Method Detail

g

public double g(SpacecraftState s)
         throws OrekitException

Description copied from class: AbstractDetector

Compute the value of the switching function. This function must be continuous (at least in its roots neighborhood), as the integrator will need to find its roots to locate the events.

Specified by:

g in interface EventDetector

Specified by:

g in class AbstractDetector

Parameters:

s - the current state information: date, kinematics, attitude for forces and events computation, mass provider, and additional states

Returns:

value of the switching function

Throws:

OrekitException - if some specific error occurs

eventOccurred

public EventDetector.Action eventOccurred(SpacecraftState s,
                                          boolean increasing,
                                          boolean forward)
                                   throws OrekitException

Handle a solar incidence event and choose what to do next.

Specified by:

eventOccurred in interface EventDetector

Specified by:

eventOccurred in class AbstractDetector

Parameters:

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

increasing - if true, the value of the switching function increases when time increases around event

forward - if true, the integration variable (time) increases during integration.

Returns:

the action performed when the expected nadir point solar incidence is detected

Throws:

OrekitException - if some specific error occurs

shouldBeRemoved

public boolean shouldBeRemoved()

This method is called after EventDetector.eventOccurred(org.orekit.propagation.SpacecraftState, boolean, boolean) has been triggered. It returns true if the current detector should be removed after first event detection. WARNING: this method can be called only once a event has been triggered. Before, the value is not available.

Specified by:

shouldBeRemoved in interface EventDetector

Specified by:

shouldBeRemoved in class AbstractDetector

Returns:

true if the current detector should be removed after first event detection

init

public void init(SpacecraftState s0,
                 AbsoluteDate t)

Description copied from class: AbstractDetector

Initialize event handler at the start of a propagation.

This method is called once at the start of the propagation. It may be used by the event handler to initialize some internal data if needed.

Specified by:

init in interface EventDetector

Overrides:

init in class AbstractDetector

Parameters:

s0 - initial state

t - target time for the integration

setSun

public void setSun(PVCoordinatesProvider sun)

Sets the sun PVCoordinatesProvider

Parameters:

sun - the sun

getSun

public PVCoordinatesProvider getSun()

Returns Sun.

Returns:

the Sun

getEarthShape

public BodyShape getEarthShape()

Returns Earth shape.

Returns:

the earth shape

getIncidence

public double getIncidence()

Returns incidence.

Returns:

incidence to detect