Examples with CelestialBody org.orekit.bodies.CelestialBody used on opensource projects

Example 11 with CelestialBody

use of org.orekit.bodies.CelestialBody in project Orekit by CS-SI.

the class DSSTPropagatorTest method testIssue339.

@Test
public void testIssue339() throws OrekitException {
    final SpacecraftState osculatingState = getLEOState();
    final CelestialBody sun = CelestialBodyFactory.getSun();
    final OneAxisEllipsoid earth = new OneAxisEllipsoid(Constants.WGS84_EARTH_EQUATORIAL_RADIUS, Constants.WGS84_EARTH_FLATTENING, FramesFactory.getITRF(IERSConventions.IERS_2010, true));
    final BoxAndSolarArraySpacecraft boxAndWing = new BoxAndSolarArraySpacecraft(5.0, 2.0, 2.0, sun, 50.0, Vector3D.PLUS_J, 2.0, 0.1, 0.2, 0.6);
    final Atmosphere atmosphere = new HarrisPriester(CelestialBodyFactory.getSun(), earth, 6);
    final AttitudeProvider attitudeProvider = new LofOffset(osculatingState.getFrame(), LOFType.VVLH, RotationOrder.XYZ, 0.0, 0.0, 0.0);
    // Surface force models that require an attitude provider
    final Collection<DSSTForceModel> forces = new ArrayList<DSSTForceModel>();
    forces.add(new DSSTSolarRadiationPressure(sun, Constants.WGS84_EARTH_EQUATORIAL_RADIUS, boxAndWing));
    forces.add(new DSSTAtmosphericDrag(atmosphere, boxAndWing));
    final SpacecraftState meanState = DSSTPropagator.computeMeanState(osculatingState, attitudeProvider, forces);
    Assert.assertEquals(0.522, Vector3D.distance(osculatingState.getPVCoordinates().getPosition(), meanState.getPVCoordinates().getPosition()), 0.001);
    final SpacecraftState computedOsculatingState = DSSTPropagator.computeOsculatingState(meanState, attitudeProvider, forces);
    Assert.assertEquals(0.0, Vector3D.distance(osculatingState.getPVCoordinates().getPosition(), computedOsculatingState.getPVCoordinates().getPosition()), 5.0e-6);
}

Example 12 with CelestialBody

use of org.orekit.bodies.CelestialBody in project Orekit by CS-SI.

the class DSSTPropagatorTest method testEphemerisGeneration.

@Test
public void testEphemerisGeneration() throws OrekitException {
    Utils.setDataRoot("regular-data:potential/icgem-format");
    GravityFieldFactory.addPotentialCoefficientsReader(new ICGEMFormatReader("^eigen-6s-truncated$", false));
    UnnormalizedSphericalHarmonicsProvider nshp = GravityFieldFactory.getUnnormalizedProvider(8, 8);
    Orbit orbit = new KeplerianOrbit(13378000, 0.05, 0, 0, FastMath.PI, 0, PositionAngle.MEAN, FramesFactory.getTOD(false), new AbsoluteDate(2003, 5, 6, TimeScalesFactory.getUTC()), nshp.getMu());
    double period = orbit.getKeplerianPeriod();
    double[][] tolerance = DSSTPropagator.tolerances(1.0, orbit);
    AdaptiveStepsizeIntegrator integrator = new DormandPrince853Integrator(period / 100, period * 100, tolerance[0], tolerance[1]);
    integrator.setInitialStepSize(10 * period);
    DSSTPropagator propagator = new DSSTPropagator(integrator, false);
    OneAxisEllipsoid earth = new OneAxisEllipsoid(Constants.WGS84_EARTH_EQUATORIAL_RADIUS, Constants.WGS84_EARTH_FLATTENING, FramesFactory.getGTOD(false));
    CelestialBody sun = CelestialBodyFactory.getSun();
    CelestialBody moon = CelestialBodyFactory.getMoon();
    propagator.addForceModel(new DSSTZonal(nshp, 8, 7, 17));
    propagator.addForceModel(new DSSTTesseral(earth.getBodyFrame(), Constants.WGS84_EARTH_ANGULAR_VELOCITY, nshp, 8, 8, 4, 12, 8, 8, 4));
    propagator.addForceModel(new DSSTThirdBody(sun));
    propagator.addForceModel(new DSSTThirdBody(moon));
    propagator.addForceModel(new DSSTAtmosphericDrag(new HarrisPriester(sun, earth), 2.1, 180));
    propagator.addForceModel(new DSSTSolarRadiationPressure(1.2, 180, sun, earth.getEquatorialRadius()));
    propagator.setInterpolationGridToMaxTimeGap(0.5 * Constants.JULIAN_DAY);
    // direct generation of states
    propagator.setInitialState(new SpacecraftState(orbit, 45.0), false);
    final List<SpacecraftState> states = new ArrayList<SpacecraftState>();
    propagator.setMasterMode(600, (currentState, isLast) -> states.add(currentState));
    propagator.propagate(orbit.getDate().shiftedBy(30 * Constants.JULIAN_DAY));
    // ephemeris generation
    propagator.setInitialState(new SpacecraftState(orbit, 45.0), false);
    propagator.setEphemerisMode();
    propagator.propagate(orbit.getDate().shiftedBy(30 * Constants.JULIAN_DAY));
    BoundedPropagator ephemeris = propagator.getGeneratedEphemeris();
    double maxError = 0;
    for (final SpacecraftState state : states) {
        final SpacecraftState fromEphemeris = ephemeris.propagate(state.getDate());
        final double error = Vector3D.distance(state.getPVCoordinates().getPosition(), fromEphemeris.getPVCoordinates().getPosition());
        maxError = FastMath.max(maxError, error);
    }
    Assert.assertEquals(0.0, maxError, 1.0e-10);
}

Example 13 with CelestialBody

use of org.orekit.bodies.CelestialBody in project Orekit by CS-SI.

the class ThirdBodyAttractionTest method testParameterDerivative.

@Test
public void testParameterDerivative() throws OrekitException {
    final Vector3D pos = new Vector3D(6.46885878304673824e+06, -1.88050918456274318e+06, -1.32931592294715829e+04);
    final Vector3D vel = new Vector3D(2.14718074509906819e+03, 7.38239351251748485e+03, -1.14097953925384523e+01);
    final SpacecraftState state = new SpacecraftState(new CartesianOrbit(new PVCoordinates(pos, vel), FramesFactory.getGCRF(), new AbsoluteDate(2003, 3, 5, 0, 24, 0.0, TimeScalesFactory.getTAI()), Constants.EIGEN5C_EARTH_MU));
    final CelestialBody moon = CelestialBodyFactory.getMoon();
    final ThirdBodyAttraction forceModel = new ThirdBodyAttraction(moon);
    Assert.assertTrue(forceModel.dependsOnPositionOnly());
    final String name = moon.getName() + ThirdBodyAttraction.ATTRACTION_COEFFICIENT_SUFFIX;
    checkParameterDerivative(state, forceModel, name, 1.0, 7.0e-15);
}

Example 14 with CelestialBody

use of org.orekit.bodies.CelestialBody in project Orekit by CS-SI.

the class ThirdBodyAttractionTest method testGlobalStateJacobian.

@Test
public void testGlobalStateJacobian() 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);
    final CelestialBody moon = CelestialBodyFactory.getMoon();
    final ThirdBodyAttraction forceModel = new ThirdBodyAttraction(moon);
    propagator.addForceModel(forceModel);
    SpacecraftState state0 = new SpacecraftState(orbit);
    checkStateJacobian(propagator, state0, date.shiftedBy(3.5 * 3600.0), 1e4, tolerances[0], 2.0e-9);
}

Example 15 with CelestialBody

use of org.orekit.bodies.CelestialBody in project Orekit by CS-SI.

the class ThirdBodyAttractionTest method accelerationDerivatives.

@Override
protected FieldVector3D<DerivativeStructure> accelerationDerivatives(final ForceModel forceModel, final AbsoluteDate date, final Frame frame, final FieldVector3D<DerivativeStructure> position, final FieldVector3D<DerivativeStructure> velocity, final FieldRotation<DerivativeStructure> rotation, final DerivativeStructure mass) throws OrekitException {
    try {
        java.lang.reflect.Field bodyField = ThirdBodyAttraction.class.getDeclaredField("body");
        bodyField.setAccessible(true);
        CelestialBody body = (CelestialBody) bodyField.get(forceModel);
        double gm = forceModel.getParameterDriver(body.getName() + ThirdBodyAttraction.ATTRACTION_COEFFICIENT_SUFFIX).getValue();
        // compute bodies separation vectors and squared norm
        final Vector3D centralToBody = body.getPVCoordinates(date, frame).getPosition();
        final double r2Central = centralToBody.getNormSq();
        final FieldVector3D<DerivativeStructure> satToBody = position.subtract(centralToBody).negate();
        final DerivativeStructure r2Sat = satToBody.getNormSq();
        // compute relative acceleration
        final FieldVector3D<DerivativeStructure> satAcc = new FieldVector3D<>(r2Sat.sqrt().multiply(r2Sat).reciprocal().multiply(gm), satToBody);
        final Vector3D centralAcc = new Vector3D(gm / (r2Central * FastMath.sqrt(r2Central)), centralToBody);
        return satAcc.subtract(centralAcc);
    } catch (IllegalArgumentException | IllegalAccessException | NoSuchFieldException | SecurityException e) {
        return null;
    }
}