NumericalPropagationWithImpulsiveManeuver
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public class NumericalPropagationWithImpulsiveManeuver {
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 = 0.01;
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(0.);
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);
//SPECIFIC
// Creating a mass model (see also specific example)
final AssemblyBuilder builder = new AssemblyBuilder();
final double iniMass = 1000.;
builder.addMainPart("MAIN");
builder.addProperty(new MassProperty(iniMass), "MAIN");
final Assembly assembly = builder.returnAssembly();
final MassProvider mm = new MassModel(assembly);
// We create a spacecratftstate
final SpacecraftState iniState = new SpacecraftState(iniOrbit, mm);
//SPECIFIC
// 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
// Event corresponding to the criteria to trigger the impulsive maneuver
final EventDetector event = new DateDetector(date.shiftedBy(10.));
// Creation of the impulsive maneuver
final Vector3D deltaV = new Vector3D(20., 0., 0.);
final double isp = 300.;
final ImpulseManeuver imp = new ImpulseManeuver(event, deltaV, isp, mm, "MAIN", LOFType.TNW);
// Adding the impulsive maneuver
propagator.addEventDetector(imp);
// Adding additional state (change name add to set for V3.3)
propagator.setMassProviderEquation(mm);
//SPECIFIC
// Propagating 100s
final double dt = 100.;
final AbsoluteDate finalDate = date.shiftedBy(dt);
final SpacecraftState finalState = propagator.propagate(finalDate);
final Orbit finalOrbit = finalState.getOrbit();
// Printing new date and semi major axis
System.out.println();
System.out.println("Initial semi major axis = "+iniOrbit.getA()/1000.+" km");
System.out.println("New date = "+finalOrbit.getDate().toString(TUC)+" deg");
System.out.println("Final semi major axis = "+finalOrbit.getA()/1000.+" km");
// Printing mass
System.out.println();
System.out.println("Mass = "+finalState.getMass("MAIN")+" kg");
}
}