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

Example 6 with BoundedPropagator

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

the class SP3ParserTest method testSP3Propagator.

@Test
public void testSP3Propagator() throws Exception {
    // setup
    final String ex = "/sp3/example-a-2.sp3";
    final Frame frame = FramesFactory.getITRF(IERSConventions.IERS_2003, true);
    final SP3Parser parser = new SP3Parser(Constants.EIGEN5C_EARTH_MU, 3, s -> frame);
    final InputStream inEntry = getClass().getResourceAsStream(ex);
    TimeScale gps = TimeScalesFactory.getGPS();
    // action
    final SP3File file = parser.parse(inEntry);
    // verify
    SP3Ephemeris ephemeris = file.getSatellites().get("1");
    BoundedPropagator propagator = ephemeris.getPropagator();
    Assert.assertEquals(propagator.getMinDate(), new AbsoluteDate(1994, 12, 17, gps));
    Assert.assertEquals(propagator.getMaxDate(), new AbsoluteDate(1994, 12, 17, 23, 45, 0, gps));
    SP3Coordinate expected = ephemeris.getCoordinates().get(0);
    checkPVEntry(propagator.getPVCoordinates(propagator.getMinDate(), frame), expected);
    expected = ephemeris.getCoordinates().get(1);
    checkPVEntry(propagator.getPVCoordinates(expected.getDate(), frame), expected);
    expected = ephemeris.getCoordinates().get(2);
    checkPVEntry(propagator.getPVCoordinates(propagator.getMaxDate(), frame), expected);
    ephemeris = file.getSatellites().get("31");
    propagator = ephemeris.getPropagator();
    Assert.assertEquals(propagator.getMinDate(), new AbsoluteDate(1994, 12, 17, gps));
    Assert.assertEquals(propagator.getMaxDate(), new AbsoluteDate(1994, 12, 17, 23, 45, 0, gps));
    expected = ephemeris.getCoordinates().get(0);
    checkPVEntry(propagator.propagate(propagator.getMinDate()).getPVCoordinates(frame), expected);
    expected = ephemeris.getCoordinates().get(1);
    checkPVEntry(propagator.propagate(expected.getDate()).getPVCoordinates(frame), expected);
    expected = ephemeris.getCoordinates().get(2);
    checkPVEntry(propagator.propagate(propagator.getMaxDate()).getPVCoordinates(frame), expected);
}

Example 7 with BoundedPropagator

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

the class BatchLSEstimatorTest method testMultiSatWithParameters.

/**
 * A modified version of the previous test with a selection of propagation drivers to estimate
 *  One common (µ)
 *  Some specifics for each satellite (Cr and Ca)
 *
 * @throws OrekitException
 */
@Test
public void testMultiSatWithParameters() throws OrekitException {
    // Test: Set the propagator drivers to estimate for each satellite
    final boolean muEstimated = true;
    final boolean crEstimated1 = true;
    final boolean caEstimated1 = true;
    final boolean crEstimated2 = true;
    final boolean caEstimated2 = false;
    // Builder sat 1
    final Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder1 = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 1.0, Force.POTENTIAL, Force.SOLAR_RADIATION_PRESSURE);
    // Adding selection of parameters
    String satName = "sat 1";
    for (DelegatingDriver driver : propagatorBuilder1.getPropagationParametersDrivers().getDrivers()) {
        if (driver.getName().equals("central attraction coefficient")) {
            driver.setSelected(muEstimated);
        }
        if (driver.getName().equals(RadiationSensitive.REFLECTION_COEFFICIENT)) {
            driver.setName(driver.getName() + " " + satName);
            driver.setSelected(crEstimated1);
        }
        if (driver.getName().equals(RadiationSensitive.ABSORPTION_COEFFICIENT)) {
            driver.setName(driver.getName() + " " + satName);
            driver.setSelected(caEstimated1);
        }
    }
    // Builder for sat 2
    final Context context2 = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder2 = context2.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 1.0, Force.POTENTIAL, Force.SOLAR_RADIATION_PRESSURE);
    // Adding selection of parameters
    satName = "sat 2";
    for (ParameterDriver driver : propagatorBuilder2.getPropagationParametersDrivers().getDrivers()) {
        if (driver.getName().equals("central attraction coefficient")) {
            driver.setSelected(muEstimated);
        }
        if (driver.getName().equals(RadiationSensitive.REFLECTION_COEFFICIENT)) {
            driver.setName(driver.getName() + " " + satName);
            driver.setSelected(crEstimated2);
        }
        if (driver.getName().equals(RadiationSensitive.ABSORPTION_COEFFICIENT)) {
            driver.setName(driver.getName() + " " + satName);
            driver.setSelected(caEstimated2);
        }
    }
    // Create perfect inter-satellites range measurements
    final TimeStampedPVCoordinates original = context.initialOrbit.getPVCoordinates();
    final Orbit closeOrbit = new CartesianOrbit(new TimeStampedPVCoordinates(context.initialOrbit.getDate(), original.getPosition().add(new Vector3D(1000, 2000, 3000)), original.getVelocity().add(new Vector3D(-0.03, 0.01, 0.02))), context.initialOrbit.getFrame(), context.initialOrbit.getMu());
    final Propagator closePropagator = EstimationTestUtils.createPropagator(closeOrbit, propagatorBuilder2);
    closePropagator.setEphemerisMode();
    closePropagator.propagate(context.initialOrbit.getDate().shiftedBy(3.5 * closeOrbit.getKeplerianPeriod()));
    final BoundedPropagator ephemeris = closePropagator.getGeneratedEphemeris();
    Propagator propagator1 = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder1);
    final List<ObservedMeasurement<?>> r12 = EstimationTestUtils.createMeasurements(propagator1, new InterSatellitesRangeMeasurementCreator(ephemeris), 1.0, 3.0, 300.0);
    // create perfect range measurements for first satellite
    propagator1 = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder1);
    final List<ObservedMeasurement<?>> r1 = EstimationTestUtils.createMeasurements(propagator1, new RangeMeasurementCreator(context), 1.0, 3.0, 300.0);
    // create orbit estimator
    final BatchLSEstimator estimator = new BatchLSEstimator(new LevenbergMarquardtOptimizer(), propagatorBuilder1, propagatorBuilder2);
    for (final ObservedMeasurement<?> interSat : r12) {
        estimator.addMeasurement(interSat);
    }
    for (final ObservedMeasurement<?> range : r1) {
        estimator.addMeasurement(range);
    }
    estimator.setParametersConvergenceThreshold(1.0e-2);
    estimator.setMaxIterations(10);
    estimator.setMaxEvaluations(20);
    estimator.setObserver(new BatchLSObserver() {

        int lastIter = 0;

        int lastEval = 0;

        /**
         * {@inheritDoc}
         */
        @Override
        public void evaluationPerformed(int iterationsCount, int evaluationscount, Orbit[] orbits, ParameterDriversList estimatedOrbitalParameters, ParameterDriversList estimatedPropagatorParameters, ParameterDriversList estimatedMeasurementsParameters, EstimationsProvider evaluationsProvider, Evaluation lspEvaluation) throws OrekitException {
            if (iterationsCount == lastIter) {
                Assert.assertEquals(lastEval + 1, evaluationscount);
            } else {
                Assert.assertEquals(lastIter + 1, iterationsCount);
            }
            lastIter = iterationsCount;
            lastEval = evaluationscount;
            AbsoluteDate previous = AbsoluteDate.PAST_INFINITY;
            for (int i = 0; i < evaluationsProvider.getNumber(); ++i) {
                AbsoluteDate current = evaluationsProvider.getEstimatedMeasurement(i).getDate();
                Assert.assertTrue(current.compareTo(previous) >= 0);
                previous = current;
            }
        }
    });
    List<DelegatingDriver> parameters = estimator.getOrbitalParametersDrivers(true).getDrivers();
    ParameterDriver a0Driver = parameters.get(0);
    Assert.assertEquals("a[0]", a0Driver.getName());
    a0Driver.setValue(a0Driver.getValue() + 1.2);
    a0Driver.setReferenceDate(AbsoluteDate.GALILEO_EPOCH);
    ParameterDriver a1Driver = parameters.get(6);
    Assert.assertEquals("a[1]", a1Driver.getName());
    a1Driver.setValue(a1Driver.getValue() - 5.4);
    a1Driver.setReferenceDate(AbsoluteDate.GALILEO_EPOCH);
    final Orbit before = new KeplerianOrbit(parameters.get(6).getValue(), parameters.get(7).getValue(), parameters.get(8).getValue(), parameters.get(9).getValue(), parameters.get(10).getValue(), parameters.get(11).getValue(), PositionAngle.TRUE, closeOrbit.getFrame(), closeOrbit.getDate(), closeOrbit.getMu());
    Assert.assertEquals(4.7246, Vector3D.distance(closeOrbit.getPVCoordinates().getPosition(), before.getPVCoordinates().getPosition()), 1.0e-3);
    Assert.assertEquals(0.0010514, Vector3D.distance(closeOrbit.getPVCoordinates().getVelocity(), before.getPVCoordinates().getVelocity()), 1.0e-6);
    EstimationTestUtils.checkFit(context, estimator, 4, 5, 0.0, 6.0e-06, 0.0, 1.7e-05, 0.0, 4.4e-07, 0.0, 1.7e-10);
    final Orbit determined = new KeplerianOrbit(parameters.get(6).getValue(), parameters.get(7).getValue(), parameters.get(8).getValue(), parameters.get(9).getValue(), parameters.get(10).getValue(), parameters.get(11).getValue(), PositionAngle.TRUE, closeOrbit.getFrame(), closeOrbit.getDate(), closeOrbit.getMu());
    Assert.assertEquals(0.0, Vector3D.distance(closeOrbit.getPVCoordinates().getPosition(), determined.getPVCoordinates().getPosition()), 5.8e-6);
    Assert.assertEquals(0.0, Vector3D.distance(closeOrbit.getPVCoordinates().getVelocity(), determined.getPVCoordinates().getVelocity()), 3.5e-9);
    // got a default one
    for (final ParameterDriver driver : estimator.getOrbitalParametersDrivers(true).getDrivers()) {
        if (driver.getName().startsWith("a[")) {
            // user-specified reference date
            Assert.assertEquals(0, driver.getReferenceDate().durationFrom(AbsoluteDate.GALILEO_EPOCH), 1.0e-15);
        } else {
            // default reference date
            Assert.assertEquals(0, driver.getReferenceDate().durationFrom(propagatorBuilder1.getInitialOrbitDate()), 1.0e-15);
        }
    }
}

Example 8 with BoundedPropagator

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

the class NumericalPropagatorTest method testEphemerisGenerationIssue14.

@Test
public void testEphemerisGenerationIssue14() throws OrekitException, IOException {
    // Propagation of the initial at t + dt
    final double dt = 3200;
    propagator.getInitialState();
    propagator.setOrbitType(OrbitType.CARTESIAN);
    propagator.setEphemerisMode();
    propagator.propagate(initDate.shiftedBy(dt));
    final BoundedPropagator ephemeris1 = propagator.getGeneratedEphemeris();
    Assert.assertEquals(initDate, ephemeris1.getMinDate());
    Assert.assertEquals(initDate.shiftedBy(dt), ephemeris1.getMaxDate());
    propagator.getPVCoordinates(initDate.shiftedBy(2 * dt), FramesFactory.getEME2000());
    propagator.getPVCoordinates(initDate.shiftedBy(-2 * dt), FramesFactory.getEME2000());
    // the new propagations should not have changed ephemeris1
    Assert.assertEquals(initDate, ephemeris1.getMinDate());
    Assert.assertEquals(initDate.shiftedBy(dt), ephemeris1.getMaxDate());
    final BoundedPropagator ephemeris2 = propagator.getGeneratedEphemeris();
    Assert.assertEquals(initDate.shiftedBy(-2 * dt), ephemeris2.getMinDate());
    Assert.assertEquals(initDate.shiftedBy(2 * dt), ephemeris2.getMaxDate());
    // generating ephemeris2 should not have changed ephemeris1
    Assert.assertEquals(initDate, ephemeris1.getMinDate());
    Assert.assertEquals(initDate.shiftedBy(dt), ephemeris1.getMaxDate());
}

Example 9 with BoundedPropagator

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

the class NumericalPropagatorTest method testEphemerisDates.

@Test
public void testEphemerisDates() throws OrekitException {
    // setup
    TimeScale tai = TimeScalesFactory.getTAI();
    AbsoluteDate initialDate = new AbsoluteDate("2015-07-01", tai);
    AbsoluteDate startDate = new AbsoluteDate("2015-07-03", tai).shiftedBy(-0.1);
    AbsoluteDate endDate = new AbsoluteDate("2015-07-04", tai);
    Frame eci = FramesFactory.getGCRF();
    KeplerianOrbit orbit = new KeplerianOrbit(600e3 + Constants.WGS84_EARTH_EQUATORIAL_RADIUS, 0, 0, 0, 0, 0, PositionAngle.TRUE, eci, initialDate, mu);
    OrbitType type = OrbitType.CARTESIAN;
    double[][] tol = NumericalPropagator.tolerances(1e-3, orbit, type);
    NumericalPropagator prop = new NumericalPropagator(new DormandPrince853Integrator(0.1, 500, tol[0], tol[1]));
    prop.setOrbitType(type);
    prop.resetInitialState(new SpacecraftState(new CartesianOrbit(orbit)));
    // action
    prop.setEphemerisMode();
    prop.propagate(startDate, endDate);
    BoundedPropagator ephemeris = prop.getGeneratedEphemeris();
    // verify
    TimeStampedPVCoordinates actualPV = ephemeris.getPVCoordinates(startDate, eci);
    TimeStampedPVCoordinates expectedPV = orbit.getPVCoordinates(startDate, eci);
    MatcherAssert.assertThat(actualPV.getPosition(), OrekitMatchers.vectorCloseTo(expectedPV.getPosition(), 1.0));
    MatcherAssert.assertThat(actualPV.getVelocity(), OrekitMatchers.vectorCloseTo(expectedPV.getVelocity(), 1.0));
    MatcherAssert.assertThat(ephemeris.getMinDate().durationFrom(startDate), OrekitMatchers.closeTo(0, 0));
    MatcherAssert.assertThat(ephemeris.getMaxDate().durationFrom(endDate), OrekitMatchers.closeTo(0, 0));
    // test date
    AbsoluteDate date = endDate.shiftedBy(-0.11);
    Assert.assertEquals(ephemeris.propagate(date).getDate().durationFrom(date), 0, 0);
}

Example 10 with BoundedPropagator

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

the class NumericalPropagatorTest method testEventAtEndOfEphemeris.

/**
 * test for issue #238
 */
@Test
public void testEventAtEndOfEphemeris() throws OrekitException {
    // setup
    // choose duration that will round up when expressed as a double
    AbsoluteDate end = initDate.shiftedBy(100).shiftedBy(3 * FastMath.ulp(100.0) / 4);
    propagator.setEphemerisMode();
    propagator.propagate(end);
    BoundedPropagator ephemeris = propagator.getGeneratedEphemeris();
    CountingHandler handler = new CountingHandler();
    DateDetector detector = new DateDetector(10, 1e-9, end).withHandler(handler);
    // propagation works fine w/o event detector, but breaks with it
    ephemeris.addEventDetector(detector);
    // action
    // fails when this throws an "out of range date for ephemerides"
    SpacecraftState actual = ephemeris.propagate(end);
    // verify
    Assert.assertEquals(actual.getDate().durationFrom(end), 0.0, 0.0);
    Assert.assertEquals(1, handler.eventCount);
}