use of org.hipparchus.ode.nonstiff.DormandPrince853Integrator in project Orekit by CS-SI.
the class ConstantThrustManeuverTest method testForwardAndBackward.
@Test
public void testForwardAndBackward() throws OrekitException {
final double isp = 318;
final double mass = 2500;
final double a = 24396159;
final double e = 0.72831215;
final double i = FastMath.toRadians(7);
final double omega = FastMath.toRadians(180);
final double OMEGA = FastMath.toRadians(261);
final double lv = 0;
final double duration = 3653.99;
final double f = 420;
final double delta = FastMath.toRadians(-7.4978);
final double alpha = FastMath.toRadians(351);
final AttitudeProvider law = new InertialProvider(new Rotation(new Vector3D(alpha, delta), Vector3D.PLUS_I));
final AbsoluteDate initDate = new AbsoluteDate(new DateComponents(2004, 01, 01), new TimeComponents(23, 30, 00.000), TimeScalesFactory.getUTC());
final Orbit orbit = new KeplerianOrbit(a, e, i, omega, OMEGA, lv, PositionAngle.TRUE, FramesFactory.getEME2000(), initDate, mu);
final SpacecraftState initialState = new SpacecraftState(orbit, law.getAttitude(orbit, orbit.getDate(), orbit.getFrame()), mass);
final AbsoluteDate fireDate = new AbsoluteDate(new DateComponents(2004, 01, 02), new TimeComponents(04, 15, 34.080), TimeScalesFactory.getUTC());
final ConstantThrustManeuver maneuver = new ConstantThrustManeuver(fireDate, duration, f, isp, Vector3D.PLUS_I);
Assert.assertEquals(f, maneuver.getThrust(), 1.0e-10);
Assert.assertEquals(isp, maneuver.getISP(), 1.0e-10);
double[][] tol = NumericalPropagator.tolerances(1.0, orbit, OrbitType.KEPLERIAN);
AdaptiveStepsizeIntegrator integrator1 = new DormandPrince853Integrator(0.001, 1000, tol[0], tol[1]);
integrator1.setInitialStepSize(60);
final NumericalPropagator propagator1 = new NumericalPropagator(integrator1);
propagator1.setInitialState(initialState);
propagator1.setAttitudeProvider(law);
propagator1.addForceModel(maneuver);
final SpacecraftState finalState = propagator1.propagate(fireDate.shiftedBy(3800));
AdaptiveStepsizeIntegrator integrator2 = new DormandPrince853Integrator(0.001, 1000, tol[0], tol[1]);
integrator2.setInitialStepSize(60);
final NumericalPropagator propagator2 = new NumericalPropagator(integrator2);
propagator2.setInitialState(finalState);
propagator2.setAttitudeProvider(law);
propagator2.addForceModel(maneuver);
final SpacecraftState recoveredState = propagator2.propagate(orbit.getDate());
final Vector3D refPosition = initialState.getPVCoordinates().getPosition();
final Vector3D recoveredPosition = recoveredState.getPVCoordinates().getPosition();
Assert.assertEquals(0.0, Vector3D.distance(refPosition, recoveredPosition), 30.0);
Assert.assertEquals(initialState.getMass(), recoveredState.getMass(), 1.5e-10);
}
use of org.hipparchus.ode.nonstiff.DormandPrince853Integrator in project Orekit by CS-SI.
the class ConstantThrustManeuverTest method RealFieldExpectErrorTest.
/**
*Same test as the previous one but not adding the ForceModel to the NumericalPropagator
* it is a test to validate the previous test.
* (to test if the ForceModel it's actually
* doing something in the Propagator and the FieldPropagator)
*/
@Test
public void RealFieldExpectErrorTest() throws OrekitException {
DSFactory factory = new DSFactory(6, 0);
DerivativeStructure a_0 = factory.variable(0, 7e7);
DerivativeStructure e_0 = factory.variable(1, 0.4);
DerivativeStructure i_0 = factory.variable(2, 85 * FastMath.PI / 180);
DerivativeStructure R_0 = factory.variable(3, 0.7);
DerivativeStructure O_0 = factory.variable(4, 0.5);
DerivativeStructure n_0 = factory.variable(5, 0.1);
Field<DerivativeStructure> field = a_0.getField();
DerivativeStructure zero = field.getZero();
FieldAbsoluteDate<DerivativeStructure> J2000 = new FieldAbsoluteDate<>(field);
Frame EME = FramesFactory.getEME2000();
FieldKeplerianOrbit<DerivativeStructure> FKO = new FieldKeplerianOrbit<>(a_0, e_0, i_0, R_0, O_0, n_0, PositionAngle.MEAN, EME, J2000, Constants.EIGEN5C_EARTH_MU);
FieldSpacecraftState<DerivativeStructure> initialState = new FieldSpacecraftState<>(FKO);
SpacecraftState iSR = initialState.toSpacecraftState();
final OrbitType type = OrbitType.KEPLERIAN;
double[][] tolerance = NumericalPropagator.tolerances(10.0, FKO.toOrbit(), type);
AdaptiveStepsizeFieldIntegrator<DerivativeStructure> integrator = new DormandPrince853FieldIntegrator<>(field, 0.001, 200, tolerance[0], tolerance[1]);
integrator.setInitialStepSize(zero.add(60));
AdaptiveStepsizeIntegrator RIntegrator = new DormandPrince853Integrator(0.001, 200, tolerance[0], tolerance[1]);
RIntegrator.setInitialStepSize(60);
FieldNumericalPropagator<DerivativeStructure> FNP = new FieldNumericalPropagator<>(field, integrator);
FNP.setOrbitType(type);
FNP.setInitialState(initialState);
NumericalPropagator NP = new NumericalPropagator(RIntegrator);
NP.setInitialState(iSR);
final ConstantThrustManeuver forceModel = new ConstantThrustManeuver(J2000.toAbsoluteDate().shiftedBy(100), 100.0, 400.0, 300.0, Vector3D.PLUS_K);
FNP.addForceModel(forceModel);
// NOT ADDING THE FORCE MODEL TO THE NUMERICAL PROPAGATOR NP.addForceModel(forceModel);
FieldAbsoluteDate<DerivativeStructure> target = J2000.shiftedBy(1000.);
FieldSpacecraftState<DerivativeStructure> finalState_DS = FNP.propagate(target);
SpacecraftState finalState_R = NP.propagate(target.toAbsoluteDate());
FieldPVCoordinates<DerivativeStructure> finPVC_DS = finalState_DS.getPVCoordinates();
PVCoordinates finPVC_R = finalState_R.getPVCoordinates();
Assert.assertFalse(FastMath.abs(finPVC_DS.toPVCoordinates().getPosition().getX() - finPVC_R.getPosition().getX()) < FastMath.abs(finPVC_R.getPosition().getX()) * 1e-11);
Assert.assertFalse(FastMath.abs(finPVC_DS.toPVCoordinates().getPosition().getY() - finPVC_R.getPosition().getY()) < FastMath.abs(finPVC_R.getPosition().getY()) * 1e-11);
Assert.assertFalse(FastMath.abs(finPVC_DS.toPVCoordinates().getPosition().getZ() - finPVC_R.getPosition().getZ()) < FastMath.abs(finPVC_R.getPosition().getZ()) * 1e-11);
}
use of org.hipparchus.ode.nonstiff.DormandPrince853Integrator in project Orekit by CS-SI.
the class SmallManeuverAnalyticalModelTest method getEphemeris.
private BoundedPropagator getEphemeris(final Orbit orbit, final double mass, final AbsoluteDate t0, final Vector3D dV, final double f, final double isp) throws OrekitException {
AttitudeProvider law = new LofOffset(orbit.getFrame(), LOFType.LVLH);
final SpacecraftState initialState = new SpacecraftState(orbit, law.getAttitude(orbit, orbit.getDate(), orbit.getFrame()), mass);
// set up numerical propagator
final double dP = 1.0;
double[][] tolerances = NumericalPropagator.tolerances(dP, orbit, orbit.getType());
AdaptiveStepsizeIntegrator integrator = new DormandPrince853Integrator(0.001, 1000, tolerances[0], tolerances[1]);
integrator.setInitialStepSize(orbit.getKeplerianPeriod() / 100.0);
final NumericalPropagator propagator = new NumericalPropagator(integrator);
propagator.setOrbitType(orbit.getType());
propagator.setInitialState(initialState);
propagator.setAttitudeProvider(law);
if (dV.getNorm() > 1.0e-6) {
// set up maneuver
final double vExhaust = Constants.G0_STANDARD_GRAVITY * isp;
final double dt = -(mass * vExhaust / f) * FastMath.expm1(-dV.getNorm() / vExhaust);
final ConstantThrustManeuver maneuver = new ConstantThrustManeuver(t0, dt, f, isp, dV.normalize());
propagator.addForceModel(maneuver);
}
propagator.setEphemerisMode();
propagator.propagate(t0.shiftedBy(5 * orbit.getKeplerianPeriod()));
return propagator.getGeneratedEphemeris();
}
use of org.hipparchus.ode.nonstiff.DormandPrince853Integrator in project Orekit by CS-SI.
the class SolarRadiationPressureTest method testGlobalStateJacobianIsotropicClassical.
@Test
public void testGlobalStateJacobianIsotropicClassical() throws OrekitException {
// initialization
AbsoluteDate date = new AbsoluteDate(new DateComponents(2003, 03, 01), new TimeComponents(13, 59, 27.816), TimeScalesFactory.getUTC());
double i = FastMath.toRadians(98.7);
double omega = FastMath.toRadians(93.0);
double OMEGA = FastMath.toRadians(15.0 * 22.5);
Orbit orbit = new KeplerianOrbit(7201009.7124401, 1e-3, i, omega, OMEGA, 0, PositionAngle.MEAN, FramesFactory.getEME2000(), date, Constants.EIGEN5C_EARTH_MU);
OrbitType integrationType = OrbitType.CARTESIAN;
double[][] tolerances = NumericalPropagator.tolerances(0.01, orbit, integrationType);
NumericalPropagator propagator = new NumericalPropagator(new DormandPrince853Integrator(1.0e-3, 120, tolerances[0], tolerances[1]));
propagator.setOrbitType(integrationType);
SolarRadiationPressure forceModel = new SolarRadiationPressure(CelestialBodyFactory.getSun(), Constants.WGS84_EARTH_EQUATORIAL_RADIUS, new IsotropicRadiationClassicalConvention(2.5, 0.7, 0.2));
propagator.addForceModel(forceModel);
SpacecraftState state0 = new SpacecraftState(orbit);
checkStateJacobian(propagator, state0, date.shiftedBy(3.5 * 3600.0), 1e6, tolerances[0], 2.0e-5);
}
use of org.hipparchus.ode.nonstiff.DormandPrince853Integrator in project Orekit by CS-SI.
the class SolarRadiationPressureTest method testRoughOrbitalModifs.
@Test
public void testRoughOrbitalModifs() throws ParseException, OrekitException, FileNotFoundException {
// initialization
AbsoluteDate date = new AbsoluteDate(new DateComponents(1970, 7, 1), new TimeComponents(13, 59, 27.816), TimeScalesFactory.getUTC());
Orbit orbit = new EquinoctialOrbit(42164000, 10e-3, 10e-3, FastMath.tan(0.001745329) * FastMath.cos(2 * FastMath.PI / 3), FastMath.tan(0.001745329) * FastMath.sin(2 * FastMath.PI / 3), 0.1, PositionAngle.TRUE, FramesFactory.getEME2000(), date, mu);
final double period = orbit.getKeplerianPeriod();
Assert.assertEquals(86164, period, 1);
PVCoordinatesProvider sun = CelestialBodyFactory.getSun();
// creation of the force model
OneAxisEllipsoid earth = new OneAxisEllipsoid(6378136.46, 1.0 / 298.25765, FramesFactory.getITRF(IERSConventions.IERS_2010, true));
SolarRadiationPressure SRP = new SolarRadiationPressure(sun, earth.getEquatorialRadius(), new IsotropicRadiationCNES95Convention(500.0, 0.7, 0.7));
// creation of the propagator
double[] absTolerance = { 0.1, 1.0e-9, 1.0e-9, 1.0e-5, 1.0e-5, 1.0e-5, 0.001 };
double[] relTolerance = { 1.0e-4, 1.0e-4, 1.0e-4, 1.0e-6, 1.0e-6, 1.0e-6, 1.0e-7 };
AdaptiveStepsizeIntegrator integrator = new DormandPrince853Integrator(900.0, 60000, absTolerance, relTolerance);
integrator.setInitialStepSize(3600);
final NumericalPropagator calc = new NumericalPropagator(integrator);
calc.addForceModel(SRP);
// Step Handler
calc.setMasterMode(FastMath.floor(period), new SolarStepHandler());
AbsoluteDate finalDate = date.shiftedBy(10 * period);
calc.setInitialState(new SpacecraftState(orbit, 1500.0));
calc.propagate(finalDate);
Assert.assertTrue(calc.getCalls() < 7100);
}
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