Admin : Page créée avec « public class NumericalPropagationWithCustomEvent { public static void main(String[] args) throws PatriusException { //... »

2018-02-13T10:21:55Z

Page créée avec « <syntaxhighlight lang="java"> public class NumericalPropagationWithCustomEvent { public static void main(String[] args) throws PatriusException { //... »

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<syntaxhighlight lang="java">
public class NumericalPropagationWithCustomEvent {

public static void main(String[] args) throws PatriusException {

// Patrius Dataset initialization (needed for example to get the UTC time)
PatriusDataset.addResourcesFromPatriusDataset() ;

// Recovery of the UTC time scale using a "factory" (not to duplicate such unique object)
final TimeScale TUC = TimeScalesFactory.getUTC();

// Date of the orbit given in UTC time scale)
final AbsoluteDate date = new AbsoluteDate("2010-01-01T12:00:00.000", TUC);

// Getting the frame with wich will defined the orbit parameters
// As for time scale, we will use also a "factory".
final Frame GCRF = FramesFactory.getGCRF();

// Initial orbit
final double sma = 7200.e+3;
final double exc = 0.02;
final double per = sma*(1.-exc);
final double apo = sma*(1.+exc);
final double inc = FastMath.toRadians(98.);
final double pa = FastMath.toRadians(0.);
final double raan = FastMath.toRadians(0.);
final double anm = FastMath.toRadians(180.);
final double MU = Constants.WGS84_EARTH_MU;

final ApsisRadiusParameters par = new ApsisRadiusParameters(per, apo, inc, pa, raan, anm, PositionAngle.MEAN, MU);
final Orbit iniOrbit = new ApsisOrbit(par, GCRF, date);

// We create a spacecratftstate
final SpacecraftState iniState = new SpacecraftState(iniOrbit);

// Initialization of the Runge Kutta integrator with a 2 s step
final double pasRk = 2.;
final FirstOrderIntegrator integrator = new ClassicalRungeKuttaIntegrator(pasRk);

// Initialization of the propagator
final NumericalPropagator propagator = new NumericalPropagator(integrator);
propagator.resetInitialState(iniState);

// Forcing integration using cartesian equations
propagator.setOrbitType(OrbitType.CARTESIAN);

//SPECIFIC
// Definition of the custom event
EventDetector event = new EventDetector() {

private static final long serialVersionUID = 1L;
public double g(SpacecraftState s) throws PatriusException {
// We want to raise the event when Lv = 45 deg
final double delta = s.getLv() - FastMath.toRadians(45.);
return delta;
}

public Action eventOccurred(SpacecraftState s, boolean increasing,
boolean forward) throws PatriusException {
System.out.println("Event occured at date : "+s.getDate().toString(TUC)+" (LM = "+FastMath.toDegrees(s.getLv())+")");
return Action.CONTINUE;
}

public boolean shouldBeRemoved() {
return false;
}
public SpacecraftState resetState(SpacecraftState oldState)
throws PatriusException {
return null;
}
public void init(SpacecraftState s0, AbsoluteDate t) {
}
public double getThreshold() {
return AbstractDetector.DEFAULT_THRESHOLD;
}
public int getSlopeSelection() {
return 0;
}
public int getMaxIterationCount() {
return 20;
}
public double getMaxCheckInterval() {
return AbstractDetector.DEFAULT_MAXCHECK;
}

};

// Adding the event to the propagator
propagator.addEventDetector(event);
//SPECIFIC

// Propagating on several orbits
final double dt = 5.*iniOrbit.getKeplerianPeriod();
final AbsoluteDate finalDate = date.shiftedBy(dt);
propagator.propagate(finalDate);

}

}
</syntaxhighlight>

NumericalPropagationWithCustomEvent - Historique des versions

Admin : Page créée avec « public class NumericalPropagationWithCustomEvent { public static void main(String[] args) throws PatriusException { //... »

Admin : Page créée avec « public class NumericalPropagationWithCustomEvent { public static void main(String[] args) throws PatriusException { //... »