use of org.orekit.propagation.conversion.NumericalPropagatorBuilder in project Orekit by CS-SI.
the class ModelTest method testBackwardPropagation.
@Test
public void testBackwardPropagation() throws OrekitException {
final 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);
final NumericalPropagatorBuilder[] builders = { propagatorBuilder };
// create perfect PV measurements
final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new PVMeasurementCreator(), 0.0, -1.0, 300.0);
final ParameterDriversList estimatedMeasurementsParameters = new ParameterDriversList();
for (ObservedMeasurement<?> measurement : measurements) {
for (final ParameterDriver driver : measurement.getParametersDrivers()) {
if (driver.isSelected()) {
estimatedMeasurementsParameters.add(driver);
}
}
}
// create model
final ModelObserver modelObserver = new ModelObserver() {
/**
* {@inheritDoc}
*/
@Override
public void modelCalled(final Orbit[] newOrbits, final Map<ObservedMeasurement<?>, EstimatedMeasurement<?>> newEvaluations) {
// Do nothing here
}
};
final Model model = new Model(builders, measurements, estimatedMeasurementsParameters, modelObserver);
// Test forward propagation flag to false
assertEquals(false, model.isForwardPropagation());
}
use of org.orekit.propagation.conversion.NumericalPropagatorBuilder in project Orekit by CS-SI.
the class OrbitDeterminationTest method run.
private ResultOD run(final File input, final boolean print) throws IOException, IllegalArgumentException, OrekitException, ParseException {
// read input parameters
KeyValueFileParser<ParameterKey> parser = new KeyValueFileParser<ParameterKey>(ParameterKey.class);
parser.parseInput(input.getAbsolutePath(), new FileInputStream(input));
// log file
final RangeLog rangeLog = new RangeLog();
final RangeRateLog rangeRateLog = new RangeRateLog();
final AzimuthLog azimuthLog = new AzimuthLog();
final ElevationLog elevationLog = new ElevationLog();
final PositionLog positionLog = new PositionLog();
final VelocityLog velocityLog = new VelocityLog();
// gravity field
GravityFieldFactory.addPotentialCoefficientsReader(new ICGEMFormatReader("eigen-5c.gfc", true));
final NormalizedSphericalHarmonicsProvider gravityField = createGravityField(parser);
// Orbit initial guess
final Orbit initialGuess = createOrbit(parser, gravityField.getMu());
// IERS conventions
final IERSConventions conventions;
if (!parser.containsKey(ParameterKey.IERS_CONVENTIONS)) {
conventions = IERSConventions.IERS_2010;
} else {
conventions = IERSConventions.valueOf("IERS_" + parser.getInt(ParameterKey.IERS_CONVENTIONS));
}
// central body
final OneAxisEllipsoid body = createBody(parser);
// propagator builder
final NumericalPropagatorBuilder propagatorBuilder = createPropagatorBuilder(parser, conventions, gravityField, body, initialGuess);
// estimator
final BatchLSEstimator estimator = createEstimator(parser, propagatorBuilder);
// measurements
final List<ObservedMeasurement<?>> measurements = new ArrayList<ObservedMeasurement<?>>();
for (final String fileName : parser.getStringsList(ParameterKey.MEASUREMENTS_FILES, ',')) {
measurements.addAll(readMeasurements(new File(input.getParentFile(), fileName), createStationsData(parser, body), createPVData(parser), createSatRangeBias(parser), createWeights(parser), createRangeOutliersManager(parser), createRangeRateOutliersManager(parser), createAzElOutliersManager(parser), createPVOutliersManager(parser)));
}
for (ObservedMeasurement<?> measurement : measurements) {
estimator.addMeasurement(measurement);
}
if (print) {
estimator.setObserver(new BatchLSObserver() {
private PVCoordinates previousPV;
{
previousPV = initialGuess.getPVCoordinates();
final String header = "iteration evaluations ΔP(m) ΔV(m/s) RMS nb Range nb Range-rate nb Angular nb PV%n";
System.out.format(Locale.US, header);
}
/**
* {@inheritDoc}
*/
@Override
public void evaluationPerformed(final int iterationsCount, final int evaluationsCount, final Orbit[] orbits, final ParameterDriversList estimatedOrbitalParameters, final ParameterDriversList estimatedPropagatorParameters, final ParameterDriversList estimatedMeasurementsParameters, final EstimationsProvider evaluationsProvider, final LeastSquaresProblem.Evaluation lspEvaluation) {
PVCoordinates currentPV = orbits[0].getPVCoordinates();
final String format0 = " %2d %2d %16.12f %s %s %s %s%n";
final String format = " %2d %2d %13.6f %12.9f %16.12f %s %s %s %s%n";
final EvaluationCounter<Range> rangeCounter = new EvaluationCounter<Range>();
final EvaluationCounter<RangeRate> rangeRateCounter = new EvaluationCounter<RangeRate>();
final EvaluationCounter<AngularAzEl> angularCounter = new EvaluationCounter<AngularAzEl>();
final EvaluationCounter<PV> pvCounter = new EvaluationCounter<PV>();
for (final Map.Entry<ObservedMeasurement<?>, EstimatedMeasurement<?>> entry : estimator.getLastEstimations().entrySet()) {
if (entry.getKey() instanceof Range) {
@SuppressWarnings("unchecked") EstimatedMeasurement<Range> evaluation = (EstimatedMeasurement<Range>) entry.getValue();
rangeCounter.add(evaluation);
} else if (entry.getKey() instanceof RangeRate) {
@SuppressWarnings("unchecked") EstimatedMeasurement<RangeRate> evaluation = (EstimatedMeasurement<RangeRate>) entry.getValue();
rangeRateCounter.add(evaluation);
} else if (entry.getKey() instanceof AngularAzEl) {
@SuppressWarnings("unchecked") EstimatedMeasurement<AngularAzEl> evaluation = (EstimatedMeasurement<AngularAzEl>) entry.getValue();
angularCounter.add(evaluation);
} else if (entry.getKey() instanceof PV) {
@SuppressWarnings("unchecked") EstimatedMeasurement<PV> evaluation = (EstimatedMeasurement<PV>) entry.getValue();
pvCounter.add(evaluation);
}
}
if (evaluationsCount == 1) {
System.out.format(Locale.US, format0, iterationsCount, evaluationsCount, lspEvaluation.getRMS(), rangeCounter.format(8), rangeRateCounter.format(8), angularCounter.format(8), pvCounter.format(8));
} else {
System.out.format(Locale.US, format, iterationsCount, evaluationsCount, Vector3D.distance(previousPV.getPosition(), currentPV.getPosition()), Vector3D.distance(previousPV.getVelocity(), currentPV.getVelocity()), lspEvaluation.getRMS(), rangeCounter.format(8), rangeRateCounter.format(8), angularCounter.format(8), pvCounter.format(8));
}
previousPV = currentPV;
}
});
}
Orbit estimated = estimator.estimate()[0].getInitialState().getOrbit();
// compute some statistics
for (final Map.Entry<ObservedMeasurement<?>, EstimatedMeasurement<?>> entry : estimator.getLastEstimations().entrySet()) {
if (entry.getKey() instanceof Range) {
@SuppressWarnings("unchecked") EstimatedMeasurement<Range> evaluation = (EstimatedMeasurement<Range>) entry.getValue();
rangeLog.add(evaluation);
} else if (entry.getKey() instanceof RangeRate) {
@SuppressWarnings("unchecked") EstimatedMeasurement<RangeRate> evaluation = (EstimatedMeasurement<RangeRate>) entry.getValue();
rangeRateLog.add(evaluation);
} else if (entry.getKey() instanceof AngularAzEl) {
@SuppressWarnings("unchecked") EstimatedMeasurement<AngularAzEl> evaluation = (EstimatedMeasurement<AngularAzEl>) entry.getValue();
azimuthLog.add(evaluation);
elevationLog.add(evaluation);
} else if (entry.getKey() instanceof PV) {
@SuppressWarnings("unchecked") EstimatedMeasurement<PV> evaluation = (EstimatedMeasurement<PV>) entry.getValue();
positionLog.add(evaluation);
velocityLog.add(evaluation);
}
}
// parmaters and measurements.
final ParameterDriversList propagatorParameters = estimator.getPropagatorParametersDrivers(true);
final ParameterDriversList measurementsParameters = estimator.getMeasurementsParametersDrivers(true);
// instation of results
return new ResultOD(propagatorParameters, measurementsParameters, estimator.getIterationsCount(), estimator.getEvaluationsCount(), estimated.getPVCoordinates(), rangeLog.createStatisticsSummary(), rangeRateLog.createStatisticsSummary(), azimuthLog.createStatisticsSummary(), elevationLog.createStatisticsSummary(), positionLog.createStatisticsSummary(), velocityLog.createStatisticsSummary(), estimator.getPhysicalCovariances(1.0e-10));
}
use of org.orekit.propagation.conversion.NumericalPropagatorBuilder in project Orekit by CS-SI.
the class AngularRaDecTest method testStateDerivatives.
@Test
public void testStateDerivatives() throws OrekitException {
Context context = EstimationTestUtils.geoStationnaryContext("regular-data:potential:tides");
final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.EQUINOCTIAL, PositionAngle.TRUE, false, 1.0e-6, 60.0, 0.001);
// create perfect azimuth-elevation measurements
final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new AngularRaDecMeasurementCreator(context), 0.25, 3.0, 600.0);
propagator.setSlaveMode();
// Compute measurements.
double[] RaerrorsP = new double[3 * measurements.size()];
double[] RaerrorsV = new double[3 * measurements.size()];
double[] DecerrorsP = new double[3 * measurements.size()];
double[] DecerrorsV = new double[3 * measurements.size()];
int RaindexP = 0;
int RaindexV = 0;
int DecindexP = 0;
int DecindexV = 0;
for (final ObservedMeasurement<?> measurement : measurements) {
// parameter corresponding to station position offset
final GroundStation stationParameter = ((AngularRaDec) measurement).getStation();
// We intentionally propagate to a date which is close to the
// real spacecraft state but is *not* the accurate date, by
// compensating only part of the downlink delay. This is done
// in order to validate the partial derivatives with respect
// to velocity. If we had chosen the proper state date, the
// angular would have depended only on the current position but
// not on the current velocity.
final AbsoluteDate datemeas = measurement.getDate();
SpacecraftState state = propagator.propagate(datemeas);
final Vector3D stationP = stationParameter.getOffsetToInertial(state.getFrame(), datemeas).transformPosition(Vector3D.ZERO);
final double meanDelay = AbstractMeasurement.signalTimeOfFlight(state.getPVCoordinates(), stationP, datemeas);
final AbsoluteDate date = measurement.getDate().shiftedBy(-0.75 * meanDelay);
state = propagator.propagate(date);
final EstimatedMeasurement<?> estimated = measurement.estimate(0, 0, new SpacecraftState[] { state });
Assert.assertEquals(2, estimated.getParticipants().length);
final double[][] jacobian = estimated.getStateDerivatives(0);
// compute a reference value using finite differences
final double[][] finiteDifferencesJacobian = Differentiation.differentiate(new StateFunction() {
public double[] value(final SpacecraftState state) throws OrekitException {
return measurement.estimate(0, 0, new SpacecraftState[] { state }).getEstimatedValue();
}
}, measurement.getDimension(), propagator.getAttitudeProvider(), OrbitType.CARTESIAN, PositionAngle.TRUE, 250.0, 4).value(state);
Assert.assertEquals(finiteDifferencesJacobian.length, jacobian.length);
Assert.assertEquals(finiteDifferencesJacobian[0].length, jacobian[0].length);
final double smallest = FastMath.ulp((double) 1.0);
for (int i = 0; i < jacobian.length; ++i) {
for (int j = 0; j < jacobian[i].length; ++j) {
double relativeError = FastMath.abs((finiteDifferencesJacobian[i][j] - jacobian[i][j]) / finiteDifferencesJacobian[i][j]);
if ((FastMath.sqrt(finiteDifferencesJacobian[i][j]) < smallest) && (FastMath.sqrt(jacobian[i][j]) < smallest)) {
relativeError = 0.0;
}
if (j < 3) {
if (i == 0) {
RaerrorsP[RaindexP++] = relativeError;
} else {
DecerrorsP[DecindexP++] = relativeError;
}
} else {
if (i == 0) {
RaerrorsV[RaindexV++] = relativeError;
} else {
DecerrorsV[DecindexV++] = relativeError;
}
}
}
}
}
// median errors on Azimuth
Assert.assertEquals(0.0, new Median().evaluate(RaerrorsP), 4.8e-11);
Assert.assertEquals(0.0, new Median().evaluate(RaerrorsV), 2.2e-5);
// median errors on Elevation
Assert.assertEquals(0.0, new Median().evaluate(DecerrorsP), 1.5e-11);
Assert.assertEquals(0.0, new Median().evaluate(DecerrorsV), 5.4e-6);
}
use of org.orekit.propagation.conversion.NumericalPropagatorBuilder in project Orekit by CS-SI.
the class AngularRaDecTest method testParameterDerivatives.
@Test
public void testParameterDerivatives() throws OrekitException {
Context context = EstimationTestUtils.geoStationnaryContext("regular-data:potential:tides");
final NumericalPropagatorBuilder propagatorBuilder = context.createBuilder(OrbitType.EQUINOCTIAL, PositionAngle.TRUE, false, 1.0e-6, 60.0, 0.001);
// create perfect azimuth-elevation 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 AngularRaDecMeasurementCreator(context), 0.25, 3.0, 600.0);
propagator.setSlaveMode();
for (final ObservedMeasurement<?> measurement : measurements) {
// parameter corresponding to station position offset
final GroundStation stationParameter = ((AngularRaDec) measurement).getStation();
// We intentionally propagate to a date which is close to the
// real spacecraft state but is *not* the accurate date, by
// compensating only part of the downlink delay. This is done
// in order to validate the partial derivatives with respect
// to velocity. If we had chosen the proper state date, the
// angular would have depended only on the current position but
// not on the current velocity.
final AbsoluteDate datemeas = measurement.getDate();
final SpacecraftState stateini = propagator.propagate(datemeas);
final Vector3D stationP = stationParameter.getOffsetToInertial(stateini.getFrame(), datemeas).transformPosition(Vector3D.ZERO);
final double meanDelay = AbstractMeasurement.signalTimeOfFlight(stateini.getPVCoordinates(), stationP, datemeas);
final AbsoluteDate date = measurement.getDate().shiftedBy(-0.75 * meanDelay);
final SpacecraftState state = propagator.propagate(date);
final ParameterDriver[] drivers = new ParameterDriver[] { stationParameter.getEastOffsetDriver(), stationParameter.getNorthOffsetDriver(), stationParameter.getZenithOffsetDriver() };
for (int i = 0; i < 3; ++i) {
final double[] gradient = measurement.estimate(0, 0, new SpacecraftState[] { state }).getParameterDerivatives(drivers[i]);
Assert.assertEquals(2, measurement.getDimension());
Assert.assertEquals(2, gradient.length);
for (final int k : new int[] { 0, 1 }) {
final ParameterFunction dMkdP = Differentiation.differentiate(new ParameterFunction() {
/**
* {@inheritDoc}
*/
@Override
public double value(final ParameterDriver parameterDriver) throws OrekitException {
return measurement.estimate(0, 0, new SpacecraftState[] { state }).getEstimatedValue()[k];
}
}, drivers[i], 3, 50.0);
final double ref = dMkdP.value(drivers[i]);
if (ref > 1.e-12) {
Assert.assertEquals(ref, gradient[k], 3e-9 * FastMath.abs(ref));
}
}
}
}
}
use of org.orekit.propagation.conversion.NumericalPropagatorBuilder in project Orekit by CS-SI.
the class GroundStationTest method testEstimateStationPosition.
@Test
public void testEstimateStationPosition() throws OrekitException, IOException, ClassNotFoundException {
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
final Propagator propagator = EstimationTestUtils.createPropagator(context.initialOrbit, propagatorBuilder);
final List<ObservedMeasurement<?>> measurements = EstimationTestUtils.createMeasurements(propagator, new RangeMeasurementCreator(context), 1.0, 3.0, 300.0);
// move one station
final RandomGenerator random = new Well19937a(0x4adbecfc743bda60l);
final TopocentricFrame base = context.stations.get(0).getBaseFrame();
final BodyShape parent = base.getParentShape();
final Vector3D baseOrigin = parent.transform(base.getPoint());
final Vector3D deltaTopo = new Vector3D(2 * random.nextDouble() - 1, 2 * random.nextDouble() - 1, 2 * random.nextDouble() - 1);
final Transform topoToParent = base.getTransformTo(parent.getBodyFrame(), (AbsoluteDate) null);
final Vector3D deltaParent = topoToParent.transformVector(deltaTopo);
final String movedSuffix = "-moved";
final GroundStation moved = new GroundStation(new TopocentricFrame(parent, parent.transform(baseOrigin.subtract(deltaParent), parent.getBodyFrame(), null), base.getName() + movedSuffix), context.ut1.getEOPHistory(), context.stations.get(0).getDisplacements());
// create orbit estimator
final BatchLSEstimator estimator = new BatchLSEstimator(new LevenbergMarquardtOptimizer(), propagatorBuilder);
for (final ObservedMeasurement<?> measurement : measurements) {
final Range range = (Range) measurement;
final String name = range.getStation().getBaseFrame().getName() + movedSuffix;
if (moved.getBaseFrame().getName().equals(name)) {
estimator.addMeasurement(new Range(moved, range.getDate(), range.getObservedValue()[0], range.getTheoreticalStandardDeviation()[0], range.getBaseWeight()[0]));
} else {
estimator.addMeasurement(range);
}
}
estimator.setParametersConvergenceThreshold(1.0e-3);
estimator.setMaxIterations(100);
estimator.setMaxEvaluations(200);
// we want to estimate station offsets
moved.getEastOffsetDriver().setSelected(true);
moved.getNorthOffsetDriver().setSelected(true);
moved.getZenithOffsetDriver().setSelected(true);
EstimationTestUtils.checkFit(context, estimator, 2, 3, 0.0, 5.6e-7, 0.0, 1.4e-6, 0.0, 4.8e-7, 0.0, 2.6e-10);
Assert.assertEquals(deltaTopo.getX(), moved.getEastOffsetDriver().getValue(), 4.5e-7);
Assert.assertEquals(deltaTopo.getY(), moved.getNorthOffsetDriver().getValue(), 6.2e-7);
Assert.assertEquals(deltaTopo.getZ(), moved.getZenithOffsetDriver().getValue(), 2.6e-7);
GeodeticPoint result = moved.getOffsetGeodeticPoint(null);
GeodeticPoint reference = context.stations.get(0).getBaseFrame().getPoint();
Assert.assertEquals(reference.getLatitude(), result.getLatitude(), 1.4e-14);
Assert.assertEquals(reference.getLongitude(), result.getLongitude(), 2.9e-14);
Assert.assertEquals(reference.getAltitude(), result.getAltitude(), 2.6e-7);
RealMatrix normalizedCovariances = estimator.getOptimum().getCovariances(1.0e-10);
RealMatrix physicalCovariances = estimator.getPhysicalCovariances(1.0e-10);
Assert.assertEquals(9, normalizedCovariances.getRowDimension());
Assert.assertEquals(9, normalizedCovariances.getColumnDimension());
Assert.assertEquals(9, physicalCovariances.getRowDimension());
Assert.assertEquals(9, physicalCovariances.getColumnDimension());
Assert.assertEquals(0.55431, physicalCovariances.getEntry(6, 6), 1.0e-5);
Assert.assertEquals(0.22694, physicalCovariances.getEntry(7, 7), 1.0e-5);
Assert.assertEquals(0.13106, physicalCovariances.getEntry(8, 8), 1.0e-5);
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(bos);
oos.writeObject(moved.getEstimatedEarthFrame().getTransformProvider());
Assert.assertTrue(bos.size() > 155000);
Assert.assertTrue(bos.size() < 160000);
ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());
ObjectInputStream ois = new ObjectInputStream(bis);
EstimatedEarthFrameProvider deserialized = (EstimatedEarthFrameProvider) ois.readObject();
Assert.assertEquals(moved.getPrimeMeridianOffsetDriver().getValue(), deserialized.getPrimeMeridianOffsetDriver().getValue(), 1.0e-15);
Assert.assertEquals(moved.getPrimeMeridianDriftDriver().getValue(), deserialized.getPrimeMeridianDriftDriver().getValue(), 1.0e-15);
Assert.assertEquals(moved.getPolarOffsetXDriver().getValue(), deserialized.getPolarOffsetXDriver().getValue(), 1.0e-15);
Assert.assertEquals(moved.getPolarDriftXDriver().getValue(), deserialized.getPolarDriftXDriver().getValue(), 1.0e-15);
Assert.assertEquals(moved.getPolarOffsetYDriver().getValue(), deserialized.getPolarOffsetYDriver().getValue(), 1.0e-15);
Assert.assertEquals(moved.getPolarDriftYDriver().getValue(), deserialized.getPolarDriftYDriver().getValue(), 1.0e-15);
}
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