Examples with BoundedPropagator org.orekit.propagation.BoundedPropagator used on opensource projects

Example 26 with BoundedPropagator

use of org.orekit.propagation.BoundedPropagator in project Orekit by CS-SI.

the class NodeDetectorTest method testIssue138.

@Test
public void testIssue138() throws OrekitException {
    double a = 800000 + Constants.WGS84_EARTH_EQUATORIAL_RADIUS;
    double e = 0.0001;
    double i = FastMath.toRadians(98);
    double w = -90;
    double raan = 0;
    double v = 0;
    Frame inertialFrame = FramesFactory.getEME2000();
    AbsoluteDate initialDate = new AbsoluteDate(2014, 01, 01, 0, 0, 0, TimeScalesFactory.getUTC());
    AbsoluteDate finalDate = initialDate.shiftedBy(5000);
    KeplerianOrbit initialOrbit = new KeplerianOrbit(a, e, i, w, raan, v, PositionAngle.TRUE, inertialFrame, initialDate, Constants.WGS84_EARTH_MU);
    SpacecraftState initialState = new SpacecraftState(initialOrbit, 1000);
    double[][] tol = NumericalPropagator.tolerances(10, initialOrbit, initialOrbit.getType());
    AdaptiveStepsizeIntegrator integrator = new DormandPrince853Integrator(0.001, 1000, tol[0], tol[1]);
    NumericalPropagator propagator = new NumericalPropagator(integrator);
    propagator.setInitialState(initialState);
    // Define 2 instances of NodeDetector:
    EventDetector rawDetector = new NodeDetector(1e-6, initialState.getOrbit(), initialState.getFrame()).withHandler(new ContinueOnEvent<NodeDetector>());
    EventsLogger logger1 = new EventsLogger();
    EventDetector node1 = logger1.monitorDetector(rawDetector);
    EventsLogger logger2 = new EventsLogger();
    EventDetector node2 = logger2.monitorDetector(rawDetector);
    propagator.addEventDetector(node1);
    propagator.addEventDetector(node2);
    // First propagation
    propagator.setEphemerisMode();
    propagator.propagate(finalDate);
    Assert.assertEquals(2, logger1.getLoggedEvents().size());
    Assert.assertEquals(2, logger2.getLoggedEvents().size());
    logger1.clearLoggedEvents();
    logger2.clearLoggedEvents();
    BoundedPropagator postpro = propagator.getGeneratedEphemeris();
    // Post-processing
    postpro.addEventDetector(node1);
    postpro.addEventDetector(node2);
    postpro.propagate(finalDate);
    Assert.assertEquals(2, logger1.getLoggedEvents().size());
    Assert.assertEquals(2, logger2.getLoggedEvents().size());
}

Example 27 with BoundedPropagator

use of org.orekit.propagation.BoundedPropagator in project Orekit by CS-SI.

the class TabulatedLofOffsetTest method testSerialization.

@Test
public void testSerialization() throws OrekitException, IOException, ClassNotFoundException {
    // create a sample from Yaw compensation law
    final LOFType type = LOFType.VNC;
    final List<TimeStampedAngularCoordinates> sample = new ArrayList<TimeStampedAngularCoordinates>();
    final AttitudeProvider yawCompensLaw = new YawCompensation(orbit.getFrame(), new NadirPointing(orbit.getFrame(), earth));
    final Propagator originalPropagator = new KeplerianPropagator(orbit);
    originalPropagator.setAttitudeProvider(yawCompensLaw);
    originalPropagator.setMasterMode(10.0, new OrekitFixedStepHandler() {

        public void handleStep(final SpacecraftState currentState, final boolean isLast) throws OrekitException {
            Rotation offsetAtt = currentState.getAttitude().getRotation();
            LofOffset aligned = new LofOffset(currentState.getFrame(), type);
            Rotation alignedAtt = aligned.getAttitude(currentState.getOrbit(), currentState.getDate(), currentState.getFrame()).getRotation();
            Rotation offsetProper = offsetAtt.compose(alignedAtt.revert(), RotationConvention.VECTOR_OPERATOR);
            sample.add(new TimeStampedAngularCoordinates(currentState.getDate(), offsetProper, Vector3D.ZERO, Vector3D.ZERO));
        }
    });
    originalPropagator.propagate(orbit.getDate().shiftedBy(2000));
    originalPropagator.setSlaveMode();
    // use the sample and generate an ephemeris
    final AttitudeProvider tabulated = new TabulatedLofOffset(orbit.getFrame(), type, sample, 6, AngularDerivativesFilter.USE_RR);
    final Propagator rebuildingPropagator = new KeplerianPropagator(orbit);
    rebuildingPropagator.setAttitudeProvider(tabulated);
    rebuildingPropagator.setEphemerisMode();
    rebuildingPropagator.propagate(orbit.getDate().shiftedBy(5));
    ByteArrayOutputStream bos = new ByteArrayOutputStream();
    ObjectOutputStream oos = new ObjectOutputStream(bos);
    oos.writeObject(rebuildingPropagator.getGeneratedEphemeris());
    // even despite we propagated only 5 seconds, the attitude sample is huge
    Assert.assertTrue(bos.size() > 17000);
    Assert.assertTrue(bos.size() < 18000);
    ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());
    ObjectInputStream ois = new ObjectInputStream(bis);
    TabulatedLofOffset deserialized = (TabulatedLofOffset) ((BoundedPropagator) ois.readObject()).getAttitudeProvider();
    Assert.assertEquals(sample.size(), deserialized.getTable().size());
}

Example 28 with BoundedPropagator

use of org.orekit.propagation.BoundedPropagator in project Orekit by CS-SI.

the class OEMParserTest method testParseOemMissingOptionalData.

@Test
public void testParseOemMissingOptionalData() throws OrekitException, IOException {
    final String ex = "/ccsds/OEMExample6.txt";
    final InputStream inEntry = getClass().getResourceAsStream(ex);
    final OEMParser parser = new OEMParser().withMu(CelestialBodyFactory.getEarth().getGM()).withConventions(IERSConventions.IERS_2010);
    final OEMFile file = parser.parse(inEntry);
    Assert.assertEquals(CcsdsTimeScale.UTC, file.getEphemeridesBlocks().get(0).getMetaData().getTimeSystem());
    Assert.assertEquals("MARS GLOBAL SURVEYOR", file.getEphemeridesBlocks().get(0).getMetaData().getObjectName());
    Assert.assertEquals("1996-062A", file.getEphemeridesBlocks().get(0).getMetaData().getObjectID());
    Assert.assertEquals(1, file.getSatellites().size());
    Assert.assertEquals(true, file.getSatellites().containsKey("1996-062A"));
    Assert.assertEquals(false, file.getSatellites().containsKey("MARS GLOBAL SURVEYOR"));
    Assert.assertEquals(1, file.getSatellites().size());
    Assert.assertEquals("1996-062A", file.getSatellites().values().iterator().next().getId());
    Assert.assertEquals(new AbsoluteDate("2002-12-18T12:00:00.331", TimeScalesFactory.getUTC()), file.getEphemeridesBlocks().get(0).getStartTime());
    OemSatelliteEphemeris satellite = file.getSatellites().get("1996-062A");
    Assert.assertEquals(satellite.getId(), "1996-062A");
    Assert.assertEquals(satellite.getMu(), file.getMuUsed(), 0);
    EphemeridesBlock actualBlock = satellite.getSegments().get(0);
    Assert.assertEquals(actualBlock.getMu(), file.getMuUsed(), 0);
    FactoryManagedFrame eme2000 = FramesFactory.getEME2000();
    Frame actualFrame = actualBlock.getFrame();
    AbsoluteDate actualStart = satellite.getStart();
    Transform actualTransform = eme2000.getTransformTo(actualFrame, actualStart);
    CelestialBody mars = CelestialBodyFactory.getMars();
    TimeStampedPVCoordinates marsPV = mars.getPVCoordinates(actualStart, eme2000);
    Assert.assertEquals(actualTransform.getTranslation(), marsPV.getPosition());
    Assert.assertEquals(actualTransform.getVelocity(), marsPV.getVelocity());
    Assert.assertEquals(actualTransform.getAcceleration(), marsPV.getAcceleration());
    Assert.assertEquals(Rotation.distance(actualTransform.getRotation(), Rotation.IDENTITY), 0.0, 0.0);
    Assert.assertEquals(actualTransform.getRotationRate(), Vector3D.ZERO);
    Assert.assertEquals(actualTransform.getRotationAcceleration(), Vector3D.ZERO);
    Assert.assertEquals(actualFrame.getName(), "Mars/EME2000");
    Assert.assertEquals(actualBlock.getFrameString(), "EME2000");
    Assert.assertEquals(actualBlock.getTimeScaleString(), "UTC");
    Assert.assertEquals(actualBlock.getTimeScale(), TimeScalesFactory.getUTC());
    Assert.assertEquals(actualBlock.getAvailableDerivatives(), CartesianDerivativesFilter.USE_PV);
    Assert.assertEquals(satellite.getSegments().get(0).getStartTime(), actualStart);
    Assert.assertEquals(satellite.getSegments().get(2).getStopTime(), satellite.getStop());
    final BoundedPropagator propagator = satellite.getPropagator();
    Assert.assertEquals(propagator.getMinDate(), satellite.getStart());
    Assert.assertEquals(propagator.getMinDate(), satellite.getSegments().get(0).getStart());
    Assert.assertEquals(propagator.getMaxDate(), satellite.getStop());
    Assert.assertEquals(propagator.getMaxDate(), satellite.getSegments().get(2).getStop());
    final List<TimeStampedPVCoordinates> dataLines = new ArrayList<>();
    for (EphemeridesBlock block : file.getEphemeridesBlocks()) {
        for (TimeStampedPVCoordinates dataLine : block.getEphemeridesDataLines()) {
            if (dataLine.getDate().compareTo(satellite.getStart()) >= 0) {
                dataLines.add(dataLine);
            }
        }
    }
    final int ulps = 12;
    for (TimeStampedPVCoordinates coord : dataLines) {
        Assert.assertThat(propagator.getPVCoordinates(coord.getDate(), actualFrame), OrekitMatchers.pvCloseTo(coord, ulps));
        Assert.assertThat(propagator.propagate(coord.getDate()).getPVCoordinates(), OrekitMatchers.pvCloseTo(coord, ulps));
    }
}

Example 29 with BoundedPropagator

use of org.orekit.propagation.BoundedPropagator in project Orekit by CS-SI.

the class SmallManeuverAnalyticalModelTest method testLowEarthOrbit2.

@Test
public void testLowEarthOrbit2() throws OrekitException {
    Orbit leo = new CircularOrbit(7200000.0, -1.0e-5, 2.0e-4, FastMath.toRadians(98.0), FastMath.toRadians(123.456), 0.0, PositionAngle.MEAN, FramesFactory.getEME2000(), new AbsoluteDate(new DateComponents(2004, 01, 01), new TimeComponents(23, 30, 00.000), TimeScalesFactory.getUTC()), Constants.EIGEN5C_EARTH_MU);
    double mass = 5600.0;
    AbsoluteDate t0 = leo.getDate().shiftedBy(1000.0);
    Vector3D dV = new Vector3D(-0.01, 0.02, 0.03);
    double f = 20.0;
    double isp = 315.0;
    BoundedPropagator withoutManeuver = getEphemeris(leo, mass, t0, Vector3D.ZERO, f, isp);
    BoundedPropagator withManeuver = getEphemeris(leo, mass, t0, dV, f, isp);
    SmallManeuverAnalyticalModel model = new SmallManeuverAnalyticalModel(withoutManeuver.propagate(t0), dV, isp);
    Assert.assertEquals(t0, model.getDate());
    for (AbsoluteDate t = withoutManeuver.getMinDate(); t.compareTo(withoutManeuver.getMaxDate()) < 0; t = t.shiftedBy(60.0)) {
        PVCoordinates pvWithout = withoutManeuver.getPVCoordinates(t, leo.getFrame());
        PVCoordinates pvWith = withManeuver.getPVCoordinates(t, leo.getFrame());
        PVCoordinates pvModel = model.apply(withoutManeuver.propagate(t).getOrbit()).getPVCoordinates(leo.getFrame());
        double nominalDeltaP = new PVCoordinates(pvWith, pvWithout).getPosition().getNorm();
        double modelError = new PVCoordinates(pvWith, pvModel).getPosition().getNorm();
        if (t.compareTo(t0) < 0) {
            // before maneuver, all positions should be equal
            Assert.assertEquals(0, nominalDeltaP, 1.0e-10);
            Assert.assertEquals(0, modelError, 1.0e-10);
        } else {
            // despite nominal deltaP exceeds 1 kilometer after less than 3 orbits
            if (t.durationFrom(t0) > 0.1 * leo.getKeplerianPeriod()) {
                Assert.assertTrue(modelError < 0.009 * nominalDeltaP);
            }
            Assert.assertTrue(modelError < 0.8);
        }
    }
}

Example 30 with BoundedPropagator

use of org.orekit.propagation.BoundedPropagator in project Orekit by CS-SI.

the class SmallManeuverAnalyticalModelTest method testJacobian.

@Test
public void testJacobian() throws OrekitException {
    Frame eme2000 = FramesFactory.getEME2000();
    Orbit leo = new CircularOrbit(7200000.0, -1.0e-2, 2.0e-3, FastMath.toRadians(98.0), FastMath.toRadians(123.456), 0.3, PositionAngle.MEAN, eme2000, new AbsoluteDate(new DateComponents(2004, 01, 01), new TimeComponents(23, 30, 00.000), TimeScalesFactory.getUTC()), Constants.EIGEN5C_EARTH_MU);
    double mass = 5600.0;
    AbsoluteDate t0 = leo.getDate().shiftedBy(1000.0);
    Vector3D dV0 = new Vector3D(-0.1, 0.2, 0.3);
    double f = 400.0;
    double isp = 315.0;
    for (OrbitType orbitType : OrbitType.values()) {
        for (PositionAngle positionAngle : PositionAngle.values()) {
            BoundedPropagator withoutManeuver = getEphemeris(orbitType.convertType(leo), mass, t0, Vector3D.ZERO, f, isp);
            SpacecraftState state0 = withoutManeuver.propagate(t0);
            SmallManeuverAnalyticalModel model = new SmallManeuverAnalyticalModel(state0, eme2000, dV0, isp);
            Assert.assertEquals(t0, model.getDate());
            Vector3D[] velDirs = new Vector3D[] { Vector3D.PLUS_I, Vector3D.PLUS_J, Vector3D.PLUS_K, Vector3D.ZERO };
            double[] timeDirs = new double[] { 0, 0, 0, 1 };
            double h = 1.0;
            AbsoluteDate t1 = t0.shiftedBy(20.0);
            for (int i = 0; i < 4; ++i) {
                SmallManeuverAnalyticalModel[] models = new SmallManeuverAnalyticalModel[] { new SmallManeuverAnalyticalModel(withoutManeuver.propagate(t0.shiftedBy(-4 * h * timeDirs[i])), eme2000, new Vector3D(1, dV0, -4 * h, velDirs[i]), isp), new SmallManeuverAnalyticalModel(withoutManeuver.propagate(t0.shiftedBy(-3 * h * timeDirs[i])), eme2000, new Vector3D(1, dV0, -3 * h, velDirs[i]), isp), new SmallManeuverAnalyticalModel(withoutManeuver.propagate(t0.shiftedBy(-2 * h * timeDirs[i])), eme2000, new Vector3D(1, dV0, -2 * h, velDirs[i]), isp), new SmallManeuverAnalyticalModel(withoutManeuver.propagate(t0.shiftedBy(-1 * h * timeDirs[i])), eme2000, new Vector3D(1, dV0, -1 * h, velDirs[i]), isp), new SmallManeuverAnalyticalModel(withoutManeuver.propagate(t0.shiftedBy(+1 * h * timeDirs[i])), eme2000, new Vector3D(1, dV0, +1 * h, velDirs[i]), isp), new SmallManeuverAnalyticalModel(withoutManeuver.propagate(t0.shiftedBy(+2 * h * timeDirs[i])), eme2000, new Vector3D(1, dV0, +2 * h, velDirs[i]), isp), new SmallManeuverAnalyticalModel(withoutManeuver.propagate(t0.shiftedBy(+3 * h * timeDirs[i])), eme2000, new Vector3D(1, dV0, +3 * h, velDirs[i]), isp), new SmallManeuverAnalyticalModel(withoutManeuver.propagate(t0.shiftedBy(+4 * h * timeDirs[i])), eme2000, new Vector3D(1, dV0, +4 * h, velDirs[i]), isp) };
                double[][] array = new double[models.length][6];
                Orbit orbitWithout = withoutManeuver.propagate(t1).getOrbit();
                // compute reference orbit gradient by finite differences
                double c = 1.0 / (840 * h);
                for (int j = 0; j < models.length; ++j) {
                    orbitType.mapOrbitToArray(models[j].apply(orbitWithout), positionAngle, array[j], null);
                }
                double[] orbitGradient = new double[6];
                for (int k = 0; k < orbitGradient.length; ++k) {
                    double d4 = array[7][k] - array[0][k];
                    double d3 = array[6][k] - array[1][k];
                    double d2 = array[5][k] - array[2][k];
                    double d1 = array[4][k] - array[3][k];
                    orbitGradient[k] = (-3 * d4 + 32 * d3 - 168 * d2 + 672 * d1) * c;
                }
                // analytical Jacobian to check
                double[][] jacobian = new double[6][4];
                model.getJacobian(orbitWithout, positionAngle, jacobian);
                for (int j = 0; j < orbitGradient.length; ++j) {
                    Assert.assertEquals(orbitGradient[j], jacobian[j][i], 1.6e-4 * FastMath.abs(orbitGradient[j]));
                }
            }
        }
    }
}