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Example 56 with Context

use of org.orekit.estimation.Context in project Orekit by CS-SI.

the class OnBoardAntennaRangeModifierTest method testEffect.

@Test
public void testEffect() throws OrekitException {
    Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 0.001);
    propagatorBuilder.setAttitudeProvider(new LofOffset(propagatorBuilder.getFrame(), LOFType.LVLH));
    // create perfect range measurements without antenna offset
    final Propagator p1 = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> spacecraftCenteredMeasurements = EstimationTestUtils.createMeasurements(p1, new RangeMeasurementCreator(context, Vector3D.ZERO), 1.0, 3.0, 300.0);
    // create perfect range measurements with antenna offset
    final Vector3D apc = new Vector3D(-2.5, 0, 0);
    final Propagator p2 = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> antennaCenteredMeasurements = EstimationTestUtils.createMeasurements(p2, new RangeMeasurementCreator(context, apc), 1.0, 3.0, 300.0);
    final Propagator p3 = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    OnBoardAntennaRangeModifier modifier = new OnBoardAntennaRangeModifier(apc);
    for (int i = 0; i < spacecraftCenteredMeasurements.size(); ++i) {
        Range sr = (Range) spacecraftCenteredMeasurements.get(i);
        sr.addModifier(modifier);
        EstimatedMeasurement<Range> estimated = sr.estimate(0, 0, new SpacecraftState[] { p3.propagate(sr.getDate()) });
        Range ar = (Range) antennaCenteredMeasurements.get(i);
        Assert.assertEquals(0.0, sr.getDate().durationFrom(ar.getDate()), 1.0e-8);
        Assert.assertEquals(ar.getObservedValue()[0], estimated.getEstimatedValue()[0], 2.6e-7);
    }
}
Also used : Context(org.orekit.estimation.Context) Vector3D(org.hipparchus.geometry.euclidean.threed.Vector3D) NumericalPropagatorBuilder(org.orekit.propagation.conversion.NumericalPropagatorBuilder) Propagator(org.orekit.propagation.Propagator) RangeMeasurementCreator(org.orekit.estimation.measurements.RangeMeasurementCreator) Range(org.orekit.estimation.measurements.Range) LofOffset(org.orekit.attitudes.LofOffset) ObservedMeasurement(org.orekit.estimation.measurements.ObservedMeasurement) Test(org.junit.Test)

Example 57 with Context

use of org.orekit.estimation.Context in project Orekit by CS-SI.

the class OnBoardAntennaRangeModifierTest method testPreliminary.

@Test
public void testPreliminary() throws OrekitException {
    // this test does not check OnBoardAntennaRangeModifier at all,
    // it just checks RangeMeasurementCreator behaves as necessary for the other test
    // the *real* test is testEffect below
    Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 0.001);
    propagatorBuilder.setAttitudeProvider(new LofOffset(propagatorBuilder.getFrame(), LOFType.LVLH));
    // create perfect range measurements without antenna offset
    final Propagator p1 = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> spacecraftCenteredMeasurements = EstimationTestUtils.createMeasurements(p1, new RangeMeasurementCreator(context, Vector3D.ZERO), 1.0, 3.0, 300.0);
    // create perfect range measurements with antenna offset
    final double xOffset = -2.5;
    final Propagator p2 = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> antennaCenteredMeasurements = EstimationTestUtils.createMeasurements(p2, new RangeMeasurementCreator(context, new Vector3D(xOffset, 0, 0)), 1.0, 3.0, 300.0);
    for (int i = 0; i < spacecraftCenteredMeasurements.size(); ++i) {
        Range sr = (Range) spacecraftCenteredMeasurements.get(i);
        Range ar = (Range) antennaCenteredMeasurements.get(i);
        double alphaMax = FastMath.asin(Constants.WGS84_EARTH_EQUATORIAL_RADIUS / sr.getObservedValue()[0]);
        Assert.assertEquals(0.0, sr.getDate().durationFrom(ar.getDate()), 1.0e-8);
        Assert.assertTrue(ar.getObservedValue()[0] - sr.getObservedValue()[0] >= xOffset);
        Assert.assertTrue(ar.getObservedValue()[0] - sr.getObservedValue()[0] <= xOffset * FastMath.cos(alphaMax));
    }
}
Also used : Context(org.orekit.estimation.Context) Vector3D(org.hipparchus.geometry.euclidean.threed.Vector3D) NumericalPropagatorBuilder(org.orekit.propagation.conversion.NumericalPropagatorBuilder) Propagator(org.orekit.propagation.Propagator) RangeMeasurementCreator(org.orekit.estimation.measurements.RangeMeasurementCreator) Range(org.orekit.estimation.measurements.Range) LofOffset(org.orekit.attitudes.LofOffset) ObservedMeasurement(org.orekit.estimation.measurements.ObservedMeasurement) Test(org.junit.Test)

Example 58 with Context

use of org.orekit.estimation.Context in project Orekit by CS-SI.

the class OnBoardAntennaTurnAroundRangeModifierTest method testEffect.

@Test
public void testEffect() throws OrekitException {
    Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 0.001);
    propagatorBuilder.setAttitudeProvider(new LofOffset(propagatorBuilder.getFrame(), LOFType.LVLH));
    // create perfect turn-around range measurements without antenna offset
    final Propagator p1 = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> spacecraftCenteredMeasurements = EstimationTestUtils.createMeasurements(p1, new TurnAroundRangeMeasurementCreator(context, Vector3D.ZERO), 1.0, 3.0, 300.0);
    // create perfect turn-around range measurements with antenna offset
    final Vector3D apc = new Vector3D(-2.5, 0, 0);
    final Propagator p2 = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> antennaCenteredMeasurements = EstimationTestUtils.createMeasurements(p2, new TurnAroundRangeMeasurementCreator(context, apc), 1.0, 3.0, 300.0);
    final Propagator p3 = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    OnBoardAntennaTurnAroundRangeModifier modifier = new OnBoardAntennaTurnAroundRangeModifier(apc);
    for (int i = 0; i < spacecraftCenteredMeasurements.size(); ++i) {
        TurnAroundRange sr = (TurnAroundRange) spacecraftCenteredMeasurements.get(i);
        sr.addModifier(modifier);
        EstimatedMeasurement<TurnAroundRange> estimated = sr.estimate(0, 0, new SpacecraftState[] { p3.propagate(sr.getDate()) });
        TurnAroundRange ar = (TurnAroundRange) antennaCenteredMeasurements.get(i);
        Assert.assertEquals(0.0, sr.getDate().durationFrom(ar.getDate()), 2.0e-8);
        Assert.assertEquals(ar.getObservedValue()[0], estimated.getEstimatedValue()[0], 5.0e-7);
    }
}
Also used : Context(org.orekit.estimation.Context) Vector3D(org.hipparchus.geometry.euclidean.threed.Vector3D) NumericalPropagatorBuilder(org.orekit.propagation.conversion.NumericalPropagatorBuilder) Propagator(org.orekit.propagation.Propagator) TurnAroundRange(org.orekit.estimation.measurements.TurnAroundRange) LofOffset(org.orekit.attitudes.LofOffset) ObservedMeasurement(org.orekit.estimation.measurements.ObservedMeasurement) TurnAroundRangeMeasurementCreator(org.orekit.estimation.measurements.TurnAroundRangeMeasurementCreator) Test(org.junit.Test)

Example 59 with Context

use of org.orekit.estimation.Context in project Orekit by CS-SI.

the class TropoModifierTest method testAngularTropoModifier.

@Test
public void testAngularTropoModifier() throws OrekitException {
    Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 0.001);
    // create perfect angular measurements
    for (final GroundStation station : context.stations) {
        station.getEastOffsetDriver().setSelected(true);
        station.getNorthOffsetDriver().setSelected(true);
        station.getZenithOffsetDriver().setSelected(true);
    }
    final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new AngularAzElMeasurementCreator(context), 1.0, 3.0, 300.0);
    propagator.setSlaveMode();
    final AngularTroposphericDelayModifier modifier = new AngularTroposphericDelayModifier(SaastamoinenModel.getStandardModel());
    for (final ObservedMeasurement<?> measurement : measurements) {
        final AbsoluteDate date = measurement.getDate();
        final SpacecraftState refState = propagator.propagate(date);
        AngularAzEl angular = (AngularAzEl) measurement;
        EstimatedMeasurement<AngularAzEl> evalNoMod = angular.estimate(0, 0, new SpacecraftState[] { refState });
        // add modifier
        angular.addModifier(modifier);
        // 
        EstimatedMeasurement<AngularAzEl> eval = angular.estimate(0, 0, new SpacecraftState[] { refState });
        final double diffAz = MathUtils.normalizeAngle(eval.getEstimatedValue()[0], evalNoMod.getEstimatedValue()[0]) - evalNoMod.getEstimatedValue()[0];
        final double diffEl = MathUtils.normalizeAngle(eval.getEstimatedValue()[1], evalNoMod.getEstimatedValue()[1]) - evalNoMod.getEstimatedValue()[1];
        // TODO: check threshold
        Assert.assertEquals(0.0, diffAz, 5.0e-5);
        Assert.assertEquals(0.0, diffEl, 5.0e-6);
    }
}
Also used : Context(org.orekit.estimation.Context) GroundStation(org.orekit.estimation.measurements.GroundStation) AbsoluteDate(org.orekit.time.AbsoluteDate) SpacecraftState(org.orekit.propagation.SpacecraftState) AngularTroposphericDelayModifier(org.orekit.estimation.measurements.modifiers.AngularTroposphericDelayModifier) NumericalPropagatorBuilder(org.orekit.propagation.conversion.NumericalPropagatorBuilder) Propagator(org.orekit.propagation.Propagator) AngularAzElMeasurementCreator(org.orekit.estimation.measurements.AngularAzElMeasurementCreator) AngularAzEl(org.orekit.estimation.measurements.AngularAzEl) ObservedMeasurement(org.orekit.estimation.measurements.ObservedMeasurement) Test(org.junit.Test)

Example 60 with Context

use of org.orekit.estimation.Context in project Orekit by CS-SI.

the class TropoModifierTest method testRangeRateTropoModifier.

@Test
public void testRangeRateTropoModifier() throws OrekitException {
    Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
    final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.KEPLERIAN, PositionAngle.TRUE, true, 1.0e-6, 60.0, 0.001);
    // create perfect range measurements
    for (final GroundStation station : context.stations) {
        station.getEastOffsetDriver().setSelected(true);
        station.getNorthOffsetDriver().setSelected(true);
        station.getZenithOffsetDriver().setSelected(true);
    }
    final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
    final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new RangeRateMeasurementCreator(context, false), 1.0, 3.0, 300.0);
    propagator.setSlaveMode();
    final RangeRateTroposphericDelayModifier modifier = new RangeRateTroposphericDelayModifier(SaastamoinenModel.getStandardModel(), false);
    for (final ObservedMeasurement<?> measurement : measurements) {
        final AbsoluteDate date = measurement.getDate();
        final SpacecraftState refState = propagator.propagate(date);
        RangeRate rangeRate = (RangeRate) measurement;
        EstimatedMeasurement<RangeRate> evalNoMod = rangeRate.estimate(0, 0, new SpacecraftState[] { refState });
        // add modifier
        rangeRate.addModifier(modifier);
        // 
        EstimatedMeasurement<RangeRate> eval = rangeRate.estimate(0, 0, new SpacecraftState[] { refState });
        final double diffMetersSec = eval.getEstimatedValue()[0] - evalNoMod.getEstimatedValue()[0];
        final double epsilon = 1e-6;
        Assert.assertTrue(Precision.compareTo(diffMetersSec, 0.01, epsilon) < 0);
        Assert.assertTrue(Precision.compareTo(diffMetersSec, -0.01, epsilon) > 0);
    }
}
Also used : Context(org.orekit.estimation.Context) GroundStation(org.orekit.estimation.measurements.GroundStation) AbsoluteDate(org.orekit.time.AbsoluteDate) SpacecraftState(org.orekit.propagation.SpacecraftState) RangeRateTroposphericDelayModifier(org.orekit.estimation.measurements.modifiers.RangeRateTroposphericDelayModifier) NumericalPropagatorBuilder(org.orekit.propagation.conversion.NumericalPropagatorBuilder) Propagator(org.orekit.propagation.Propagator) RangeRate(org.orekit.estimation.measurements.RangeRate) ObservedMeasurement(org.orekit.estimation.measurements.ObservedMeasurement) RangeRateMeasurementCreator(org.orekit.estimation.measurements.RangeRateMeasurementCreator) Test(org.junit.Test)

Aggregations

Context (org.orekit.estimation.Context)74 Propagator (org.orekit.propagation.Propagator)67 NumericalPropagatorBuilder (org.orekit.propagation.conversion.NumericalPropagatorBuilder)67 Test (org.junit.Test)60 AbsoluteDate (org.orekit.time.AbsoluteDate)49 ObservedMeasurement (org.orekit.estimation.measurements.ObservedMeasurement)40 SpacecraftState (org.orekit.propagation.SpacecraftState)35 Vector3D (org.hipparchus.geometry.euclidean.threed.Vector3D)28 ParameterDriver (org.orekit.utils.ParameterDriver)21 OrekitException (org.orekit.errors.OrekitException)18 Median (org.hipparchus.stat.descriptive.rank.Median)17 RangeMeasurementCreator (org.orekit.estimation.measurements.RangeMeasurementCreator)17 Orbit (org.orekit.orbits.Orbit)17 ParameterDriversList (org.orekit.utils.ParameterDriversList)16 ArrayList (java.util.ArrayList)14 Max (org.hipparchus.stat.descriptive.rank.Max)14 BoundedPropagator (org.orekit.propagation.BoundedPropagator)13 RealMatrix (org.hipparchus.linear.RealMatrix)12 LevenbergMarquardtOptimizer (org.hipparchus.optim.nonlinear.vector.leastsquares.LevenbergMarquardtOptimizer)12 StateFunction (org.orekit.utils.StateFunction)11