Examples with AdaptiveStepsizeIntegrator org.hipparchus.ode.nonstiff.AdaptiveStepsizeIntegrator used on opensource projects

Example 41 with AdaptiveStepsizeIntegrator

use of org.hipparchus.ode.nonstiff.AdaptiveStepsizeIntegrator in project Orekit by CS-SI.

the class DSSTPropagatorTest method getLEOStatePropagatedBy30Minutes.

private SpacecraftState getLEOStatePropagatedBy30Minutes() throws IllegalArgumentException, OrekitException {
    final Vector3D position = new Vector3D(-6142438.668, 3492467.560, -25767.25680);
    final Vector3D velocity = new Vector3D(505.8479685, 942.7809215, 7435.922231);
    // Spring equinoxe 21st mars 2003 1h00m
    final AbsoluteDate initialDate = new AbsoluteDate(new DateComponents(2003, 03, 21), new TimeComponents(1, 0, 0.), TimeScalesFactory.getUTC());
    final CartesianOrbit osculatingOrbit = new CartesianOrbit(new PVCoordinates(position, velocity), FramesFactory.getTOD(IERSConventions.IERS_1996, false), initialDate, Constants.WGS84_EARTH_MU);
    // Adaptive step integrator
    // with a minimum step of 0.001 and a maximum step of 1000
    double minStep = 0.001;
    double maxstep = 1000.0;
    double positionTolerance = 10.0;
    OrbitType propagationType = OrbitType.EQUINOCTIAL;
    double[][] tolerances = NumericalPropagator.tolerances(positionTolerance, osculatingOrbit, propagationType);
    AdaptiveStepsizeIntegrator integrator = new DormandPrince853Integrator(minStep, maxstep, tolerances[0], tolerances[1]);
    NumericalPropagator propagator = new NumericalPropagator(integrator);
    propagator.setOrbitType(propagationType);
    NormalizedSphericalHarmonicsProvider provider = GravityFieldFactory.getNormalizedProvider(5, 5);
    ForceModel holmesFeatherstone = new HolmesFeatherstoneAttractionModel(FramesFactory.getITRF(IERSConventions.IERS_2010, true), provider);
    propagator.addForceModel(holmesFeatherstone);
    propagator.setInitialState(new SpacecraftState(osculatingOrbit));
    return propagator.propagate(new AbsoluteDate(initialDate, 1800.));
}

Example 42 with AdaptiveStepsizeIntegrator

use of org.hipparchus.ode.nonstiff.AdaptiveStepsizeIntegrator in project Orekit by CS-SI.

the class DSSTPropagatorTest method testGetInitialOsculatingState.

@Test
public void testGetInitialOsculatingState() throws IllegalArgumentException, OrekitException {
    final SpacecraftState initialState = getGEOState();
    // build integrator
    final double minStep = initialState.getKeplerianPeriod() * 0.1;
    final double maxStep = initialState.getKeplerianPeriod() * 10.0;
    final double[][] tol = DSSTPropagator.tolerances(0.1, initialState.getOrbit());
    AdaptiveStepsizeIntegrator integrator = new DormandPrince853Integrator(minStep, maxStep, tol[0], tol[1]);
    // build the propagator for the propagation of the mean elements
    DSSTPropagator prop = new DSSTPropagator(integrator, true);
    final UnnormalizedSphericalHarmonicsProvider provider = GravityFieldFactory.getUnnormalizedProvider(4, 0);
    final Frame earthFrame = CelestialBodyFactory.getEarth().getBodyOrientedFrame();
    DSSTForceModel zonal = new DSSTZonal(provider, 4, 3, 9);
    DSSTForceModel tesseral = new DSSTTesseral(earthFrame, Constants.WGS84_EARTH_ANGULAR_VELOCITY, provider, 4, 0, 4, 8, 4, 0, 2);
    prop.addForceModel(zonal);
    prop.addForceModel(tesseral);
    // Set the initial state as osculating
    prop.setInitialState(initialState, false);
    // Check the stored initial state is the osculating one
    Assert.assertEquals(initialState, prop.getInitialState());
    // Check that no propagation, i.e. propagation to the initial date, provides the initial
    // osculating state although the propagator is configured to propagate mean elements !!!
    Assert.assertEquals(initialState, prop.propagate(initialState.getDate()));
}

Example 43 with AdaptiveStepsizeIntegrator

use of org.hipparchus.ode.nonstiff.AdaptiveStepsizeIntegrator in project Orekit by CS-SI.

the class AdditionalEquationsTest method testInitNumerical.

/**
 * Test for issue #401
 *  with a numerical propagator
 */
@Test
public void testInitNumerical() throws OrekitException {
    // setup
    final double reference = 1.25;
    InitCheckerEquations checker = new InitCheckerEquations(reference);
    Assert.assertFalse(checker.wasCalled());
    // action
    AdaptiveStepsizeIntegrator integrator = new DormandPrince853Integrator(0.001, 200, tolerance[0], tolerance[1]);
    integrator.setInitialStepSize(60);
    NumericalPropagator propagatorNumerical = new NumericalPropagator(integrator);
    propagatorNumerical.setInitialState(initialState.addAdditionalState(checker.getName(), reference));
    propagatorNumerical.addAdditionalEquations(checker);
    propagatorNumerical.propagate(initDate.shiftedBy(600));
    // verify
    Assert.assertTrue(checker.wasCalled());
}

Example 44 with AdaptiveStepsizeIntegrator

use of org.hipparchus.ode.nonstiff.AdaptiveStepsizeIntegrator in project Orekit by CS-SI.

the class AdditionalEquationsTest method testInitDSST.

/**
 * Test for issue #401
 *  with a DSST propagator
 */
@Test
public void testInitDSST() throws OrekitException {
    // setup
    final double reference = 3.5;
    InitCheckerEquations checker = new InitCheckerEquations(reference);
    Assert.assertFalse(checker.wasCalled());
    // action
    AdaptiveStepsizeIntegrator integrator = new DormandPrince853Integrator(0.001, 200, tolerance[0], tolerance[1]);
    integrator.setInitialStepSize(60);
    DSSTPropagator propagatorDSST = new DSSTPropagator(integrator);
    propagatorDSST.setInitialState(initialState.addAdditionalState(checker.getName(), reference));
    propagatorDSST.addAdditionalEquations(checker);
    propagatorDSST.propagate(initDate.shiftedBy(600));
    // verify
    Assert.assertTrue(checker.wasCalled());
}

Example 45 with AdaptiveStepsizeIntegrator

use of org.hipparchus.ode.nonstiff.AdaptiveStepsizeIntegrator in project Orekit by CS-SI.

the class IntegratedEphemerisTest method doTestSerializationDSST.

private void doTestSerializationDSST(boolean meanOnly, int expectedSize) throws OrekitException, IOException, ClassNotFoundException {
    AbsoluteDate finalDate = initialOrbit.getDate().shiftedBy(Constants.JULIAN_DAY);
    final double[][] tol = DSSTPropagator.tolerances(1.0, initialOrbit);
    AdaptiveStepsizeIntegrator integrator = new DormandPrince853Integrator(10, Constants.JULIAN_DAY, tol[0], tol[1]);
    DSSTPropagator dsstProp = new DSSTPropagator(integrator, meanOnly);
    dsstProp.setInitialState(new SpacecraftState(initialOrbit), false);
    dsstProp.setEphemerisMode();
    final Frame itrf = FramesFactory.getITRF(IERSConventions.IERS_2010, true);
    final UnnormalizedSphericalHarmonicsProvider gravity = GravityFieldFactory.getUnnormalizedProvider(8, 8);
    final CelestialBody sun = CelestialBodyFactory.getSun();
    final CelestialBody moon = CelestialBodyFactory.getMoon();
    final RadiationSensitive spacecraft = new IsotropicRadiationSingleCoefficient(20.0, 2.0);
    dsstProp.addForceModel(new DSSTZonal(gravity, 8, 7, 17));
    dsstProp.addForceModel(new DSSTTesseral(itrf, Constants.WGS84_EARTH_ANGULAR_VELOCITY, gravity, 8, 8, 4, 12, 8, 8, 4));
    dsstProp.addForceModel(new DSSTThirdBody(sun));
    dsstProp.addForceModel(new DSSTThirdBody(moon));
    dsstProp.addForceModel(new DSSTSolarRadiationPressure(sun, Constants.WGS84_EARTH_EQUATORIAL_RADIUS, spacecraft));
    dsstProp.propagate(finalDate);
    IntegratedEphemeris ephemeris = (IntegratedEphemeris) dsstProp.getGeneratedEphemeris();
    ByteArrayOutputStream bos = new ByteArrayOutputStream();
    ObjectOutputStream oos = new ObjectOutputStream(bos);
    oos.writeObject(ephemeris);
    Assert.assertTrue("size = " + bos.size(), bos.size() > 9 * expectedSize / 10);
    Assert.assertTrue("size = " + bos.size(), bos.size() < 11 * expectedSize / 10);
    Assert.assertNotNull(ephemeris.getFrame());
    Assert.assertSame(ephemeris.getFrame(), dsstProp.getFrame());
    ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());
    ObjectInputStream ois = new ObjectInputStream(bis);
    IntegratedEphemeris deserialized = (IntegratedEphemeris) ois.readObject();
    Assert.assertEquals(deserialized.getMinDate(), deserialized.getMinDate());
    Assert.assertEquals(deserialized.getMaxDate(), deserialized.getMaxDate());
}