use of org.orekit.propagation.conversion.NumericalPropagatorBuilder in project Orekit by CS-SI.
the class KalmanOrbitDeterminationTest method run.
/**
* Function running the Kalman filter estimation.
* @param input Input configuration file
* @param orbitType Orbit type to use (calculation and display)
* @param print Choose whether the results are printed on console or not
* @param cartesianOrbitalP Orbital part of the initial covariance matrix in Cartesian formalism
* @param cartesianOrbitalQ Orbital part of the process noise matrix in Cartesian formalism
* @param propagationP Propagation part of the initial covariance matrix
* @param propagationQ Propagation part of the process noise matrix
* @param measurementP Measurement part of the initial covariance matrix
* @param measurementQ Measurement part of the process noise matrix
*/
private ResultKalman run(final File input, final OrbitType orbitType, final boolean print, final RealMatrix cartesianOrbitalP, final RealMatrix cartesianOrbitalQ, final RealMatrix propagationP, final RealMatrix propagationQ, final RealMatrix measurementP, final RealMatrix measurementQ) throws IOException, IllegalArgumentException, OrekitException, ParseException {
// Read input parameters
KeyValueFileParser<ParameterKey> parser = new KeyValueFileParser<ParameterKey>(ParameterKey.class);
parser.parseInput(input.getAbsolutePath(), new FileInputStream(input));
// Log files
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
Orbit initialGuess = createOrbit(parser, gravityField.getMu());
// Convert to desired orbit type
initialGuess = orbitType.convertType(initialGuess);
// 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);
// 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)));
}
// Building the Kalman filter:
// - Gather the estimated measurement parameters in a list
// - Prepare the initial covariance matrix and the process noise matrix
// - Build the Kalman filter
// --------------------------------------------------------------------
// Build the list of estimated measurements
final ParameterDriversList estimatedMeasurementsParameters = new ParameterDriversList();
for (ObservedMeasurement<?> measurement : measurements) {
final List<ParameterDriver> drivers = measurement.getParametersDrivers();
for (ParameterDriver driver : drivers) {
if (driver.isSelected()) {
// Add the driver
estimatedMeasurementsParameters.add(driver);
}
}
}
// Sort the list lexicographically
estimatedMeasurementsParameters.sort();
// Orbital covariance matrix initialization
// Jacobian of the orbital parameters w/r to Cartesian
final double[][] dYdC = new double[6][6];
initialGuess.getJacobianWrtCartesian(propagatorBuilder.getPositionAngle(), dYdC);
final RealMatrix Jac = MatrixUtils.createRealMatrix(dYdC);
RealMatrix orbitalP = Jac.multiply(cartesianOrbitalP.multiply(Jac.transpose()));
// Orbital process noise matrix
RealMatrix orbitalQ = Jac.multiply(cartesianOrbitalQ.multiply(Jac.transpose()));
// Build the full covariance matrix and process noise matrix
final int nbPropag = (propagationP != null) ? propagationP.getRowDimension() : 0;
final int nbMeas = (measurementP != null) ? measurementP.getRowDimension() : 0;
final RealMatrix initialP = MatrixUtils.createRealMatrix(6 + nbPropag + nbMeas, 6 + nbPropag + nbMeas);
final RealMatrix Q = MatrixUtils.createRealMatrix(6 + nbPropag + nbMeas, 6 + nbPropag + nbMeas);
// Orbital part
initialP.setSubMatrix(orbitalP.getData(), 0, 0);
Q.setSubMatrix(orbitalQ.getData(), 0, 0);
// Propagation part
if (propagationP != null) {
initialP.setSubMatrix(propagationP.getData(), 6, 6);
Q.setSubMatrix(propagationQ.getData(), 6, 6);
}
// Measurement part
if (measurementP != null) {
initialP.setSubMatrix(measurementP.getData(), 6 + nbPropag, 6 + nbPropag);
Q.setSubMatrix(measurementQ.getData(), 6 + nbPropag, 6 + nbPropag);
}
// Build the Kalman
KalmanEstimatorBuilder kalmanBuilder = new KalmanEstimatorBuilder();
kalmanBuilder.builder(propagatorBuilder);
kalmanBuilder.estimatedMeasurementsParameters(estimatedMeasurementsParameters);
kalmanBuilder.initialCovarianceMatrix(initialP);
kalmanBuilder.processNoiseMatrixProvider(new ConstantProcessNoise(Q));
final KalmanEstimator kalman = kalmanBuilder.build();
// Add an observer
kalman.setObserver(new KalmanObserver() {
/**
* Date of the first measurement.
*/
private AbsoluteDate t0;
/**
* {@inheritDoc}
* @throws OrekitException
*/
@Override
@SuppressWarnings("unchecked")
public void evaluationPerformed(final KalmanEstimation estimation) throws OrekitException {
// Current measurement number, date and status
final EstimatedMeasurement<?> estimatedMeasurement = estimation.getCorrectedMeasurement();
final int currentNumber = estimation.getCurrentMeasurementNumber();
final AbsoluteDate currentDate = estimatedMeasurement.getDate();
final EstimatedMeasurement.Status currentStatus = estimatedMeasurement.getStatus();
// Current estimated measurement
final ObservedMeasurement<?> observedMeasurement = estimatedMeasurement.getObservedMeasurement();
// Measurement type & Station name
String measType = "";
String stationName = "";
// Register the measurement in the proper measurement logger
if (observedMeasurement instanceof Range) {
// Add the tuple (estimation, prediction) to the log
rangeLog.add(currentNumber, (EstimatedMeasurement<Range>) estimatedMeasurement);
// Measurement type & Station name
measType = "RANGE";
stationName = ((EstimatedMeasurement<Range>) estimatedMeasurement).getObservedMeasurement().getStation().getBaseFrame().getName();
} else if (observedMeasurement instanceof RangeRate) {
rangeRateLog.add(currentNumber, (EstimatedMeasurement<RangeRate>) estimatedMeasurement);
measType = "RANGE_RATE";
stationName = ((EstimatedMeasurement<RangeRate>) estimatedMeasurement).getObservedMeasurement().getStation().getBaseFrame().getName();
} else if (observedMeasurement instanceof AngularAzEl) {
azimuthLog.add(currentNumber, (EstimatedMeasurement<AngularAzEl>) estimatedMeasurement);
elevationLog.add(currentNumber, (EstimatedMeasurement<AngularAzEl>) estimatedMeasurement);
measType = "AZ_EL";
stationName = ((EstimatedMeasurement<AngularAzEl>) estimatedMeasurement).getObservedMeasurement().getStation().getBaseFrame().getName();
} else if (observedMeasurement instanceof PV) {
positionLog.add(currentNumber, (EstimatedMeasurement<PV>) estimatedMeasurement);
velocityLog.add(currentNumber, (EstimatedMeasurement<PV>) estimatedMeasurement);
measType = "PV";
}
// Header
if (print) {
if (currentNumber == 1) {
// Set t0 to first measurement date
t0 = currentDate;
// Print header
final String formatHeader = "%-4s\t%-25s\t%15s\t%-10s\t%-10s\t%-20s\t%20s\t%20s";
String header = String.format(Locale.US, formatHeader, "Nb", "Epoch", "Dt[s]", "Status", "Type", "Station", "DP Corr", "DV Corr");
// Orbital drivers
for (DelegatingDriver driver : estimation.getEstimatedOrbitalParameters().getDrivers()) {
header += String.format(Locale.US, "\t%20s", driver.getName());
header += String.format(Locale.US, "\t%20s", "D" + driver.getName());
}
// Propagation drivers
for (DelegatingDriver driver : estimation.getEstimatedPropagationParameters().getDrivers()) {
header += String.format(Locale.US, "\t%20s", driver.getName());
header += String.format(Locale.US, "\t%20s", "D" + driver.getName());
}
// Measurements drivers
for (DelegatingDriver driver : estimation.getEstimatedMeasurementsParameters().getDrivers()) {
header += String.format(Locale.US, "\t%20s", driver.getName());
header += String.format(Locale.US, "\t%20s", "D" + driver.getName());
}
// Print header
System.out.println(header);
}
// Print current measurement info in terminal
String line = "";
// Line format
final String lineFormat = "%4d\t%-25s\t%15.3f\t%-10s\t%-10s\t%-20s\t%20.9e\t%20.9e";
// Orbital correction = DP & DV between predicted orbit and estimated orbit
final Vector3D predictedP = estimation.getPredictedSpacecraftStates()[0].getPVCoordinates().getPosition();
final Vector3D predictedV = estimation.getPredictedSpacecraftStates()[0].getPVCoordinates().getVelocity();
final Vector3D estimatedP = estimation.getCorrectedSpacecraftStates()[0].getPVCoordinates().getPosition();
final Vector3D estimatedV = estimation.getCorrectedSpacecraftStates()[0].getPVCoordinates().getVelocity();
final double DPcorr = Vector3D.distance(predictedP, estimatedP);
final double DVcorr = Vector3D.distance(predictedV, estimatedV);
line = String.format(Locale.US, lineFormat, currentNumber, currentDate.toString(), currentDate.durationFrom(t0), currentStatus.toString(), measType, stationName, DPcorr, DVcorr);
// Handle parameters printing (value and error)
int jPar = 0;
final RealMatrix Pest = estimation.getPhysicalEstimatedCovarianceMatrix();
// Orbital drivers
for (DelegatingDriver driver : estimation.getEstimatedOrbitalParameters().getDrivers()) {
line += String.format(Locale.US, "\t%20.9f", driver.getValue());
line += String.format(Locale.US, "\t%20.9e", FastMath.sqrt(Pest.getEntry(jPar, jPar)));
jPar++;
}
// Propagation drivers
for (DelegatingDriver driver : estimation.getEstimatedPropagationParameters().getDrivers()) {
line += String.format(Locale.US, "\t%20.9f", driver.getValue());
line += String.format(Locale.US, "\t%20.9e", FastMath.sqrt(Pest.getEntry(jPar, jPar)));
jPar++;
}
// Measurements drivers
for (DelegatingDriver driver : estimatedMeasurementsParameters.getDrivers()) {
line += String.format(Locale.US, "\t%20.9f", driver.getValue());
line += String.format(Locale.US, "\t%20.9e", FastMath.sqrt(Pest.getEntry(jPar, jPar)));
jPar++;
}
// Print the line
System.out.println(line);
}
}
});
// Process the list measurements
final Orbit estimated = kalman.processMeasurements(measurements).getInitialState().getOrbit();
// Get the last estimated physical covariances
final RealMatrix covarianceMatrix = kalman.getPhysicalEstimatedCovarianceMatrix();
// Parameters and measurements.
final ParameterDriversList propagationParameters = kalman.getPropagationParametersDrivers(true);
final ParameterDriversList measurementsParameters = kalman.getEstimatedMeasurementsParameters();
// Eventually, print parameter changes, statistics and covariances
if (print) {
// Display parameter change for non orbital drivers
int length = 0;
for (final ParameterDriver parameterDriver : propagationParameters.getDrivers()) {
length = FastMath.max(length, parameterDriver.getName().length());
}
for (final ParameterDriver parameterDriver : measurementsParameters.getDrivers()) {
length = FastMath.max(length, parameterDriver.getName().length());
}
if (propagationParameters.getNbParams() > 0) {
displayParametersChanges(System.out, "Estimated propagator parameters changes: ", true, length, propagationParameters);
}
if (measurementsParameters.getNbParams() > 0) {
displayParametersChanges(System.out, "Estimated measurements parameters changes: ", true, length, measurementsParameters);
}
// Measurements statistics summary
System.out.println("");
rangeLog.displaySummary(System.out);
rangeRateLog.displaySummary(System.out);
azimuthLog.displaySummary(System.out);
elevationLog.displaySummary(System.out);
positionLog.displaySummary(System.out);
velocityLog.displaySummary(System.out);
// Covariances and sigmas
displayFinalCovariances(System.out, kalman);
}
// Instantiation of the results
return new ResultKalman(propagationParameters, measurementsParameters, kalman.getCurrentMeasurementNumber(), estimated.getPVCoordinates(), rangeLog.createStatisticsSummary(), rangeRateLog.createStatisticsSummary(), azimuthLog.createStatisticsSummary(), elevationLog.createStatisticsSummary(), positionLog.createStatisticsSummary(), velocityLog.createStatisticsSummary(), covarianceMatrix);
}
use of org.orekit.propagation.conversion.NumericalPropagatorBuilder in project Orekit by CS-SI.
the class BatchLSEstimatorTest method testKeplerRange.
/**
* Perfect range measurements with a biased start
* @throws OrekitException
*/
@Test
public void testKeplerRange() 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, 1.0);
// 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);
// create orbit estimator
final BatchLSEstimator estimator = new BatchLSEstimator(new LevenbergMarquardtOptimizer(), propagatorBuilder);
for (final ObservedMeasurement<?> range : measurements) {
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;
Assert.assertEquals(measurements.size(), evaluationsProvider.getNumber());
try {
evaluationsProvider.getEstimatedMeasurement(-1);
Assert.fail("an exception should have been thrown");
} catch (OrekitException oe) {
Assert.assertEquals(LocalizedCoreFormats.OUT_OF_RANGE_SIMPLE, oe.getSpecifier());
}
try {
evaluationsProvider.getEstimatedMeasurement(measurements.size());
Assert.fail("an exception should have been thrown");
} catch (OrekitException oe) {
Assert.assertEquals(LocalizedCoreFormats.OUT_OF_RANGE_SIMPLE, oe.getSpecifier());
}
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;
}
}
});
ParameterDriver aDriver = estimator.getOrbitalParametersDrivers(true).getDrivers().get(0);
Assert.assertEquals("a", aDriver.getName());
aDriver.setValue(aDriver.getValue() + 1.2);
aDriver.setReferenceDate(AbsoluteDate.GALILEO_EPOCH);
EstimationTestUtils.checkFit(context, estimator, 2, 3, 0.0, 1.1e-6, 0.0, 2.8e-6, 0.0, 4.0e-7, 0.0, 2.2e-10);
// got a default one
for (final ParameterDriver driver : estimator.getOrbitalParametersDrivers(true).getDrivers()) {
if ("a".equals(driver.getName())) {
// 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(propagatorBuilder.getInitialOrbitDate()), 1.0e-15);
}
}
}
use of org.orekit.propagation.conversion.NumericalPropagatorBuilder in project Orekit by CS-SI.
the class ModelTest method testPerfectValue.
@Test
public void testPerfectValue() 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) {
Assert.assertEquals(1, newOrbits.length);
Assert.assertEquals(0, context.initialOrbit.getDate().durationFrom(newOrbits[0].getDate()), 1.0e-15);
Assert.assertEquals(0, Vector3D.distance(context.initialOrbit.getPVCoordinates().getPosition(), newOrbits[0].getPVCoordinates().getPosition()), 1.0e-15);
Assert.assertEquals(measurements.size(), newEvaluations.size());
}
};
final Model model = new Model(builders, measurements, estimatedMeasurementsParameters, modelObserver);
model.setIterationsCounter(new Incrementor(100));
model.setEvaluationsCounter(new Incrementor(100));
// Test forward propagation flag to true
assertEquals(true, model.isForwardPropagation());
// evaluate model on perfect start point
final double[] normalizedProp = propagatorBuilder.getSelectedNormalizedParameters();
final double[] normalized = new double[normalizedProp.length + estimatedMeasurementsParameters.getNbParams()];
System.arraycopy(normalizedProp, 0, normalized, 0, normalizedProp.length);
int i = normalizedProp.length;
for (final ParameterDriver driver : estimatedMeasurementsParameters.getDrivers()) {
normalized[i++] = driver.getNormalizedValue();
}
Pair<RealVector, RealMatrix> value = model.value(new ArrayRealVector(normalized));
int index = 0;
for (ObservedMeasurement<?> measurement : measurements) {
for (int k = 0; k < measurement.getDimension(); ++k) {
// the value is already a weighted residual
Assert.assertEquals(0.0, value.getFirst().getEntry(index++), 1.6e-7);
}
}
Assert.assertEquals(index, value.getFirst().getDimension());
}
use of org.orekit.propagation.conversion.NumericalPropagatorBuilder in project Orekit by CS-SI.
the class OrbitDeterminationTest method createPropagatorBuilder.
/**
* Create a propagator builder from input parameters
* @param parser input file parser
* @param conventions IERS conventions to use
* @param gravityField gravity field
* @param body central body
* @param orbit first orbit estimate
* @return propagator builder
* @throws NoSuchElementException if input parameters are missing
* @throws OrekitException if body frame cannot be created
*/
private NumericalPropagatorBuilder createPropagatorBuilder(final KeyValueFileParser<ParameterKey> parser, final IERSConventions conventions, final NormalizedSphericalHarmonicsProvider gravityField, final OneAxisEllipsoid body, final Orbit orbit) throws NoSuchElementException, OrekitException {
final double minStep;
if (!parser.containsKey(ParameterKey.PROPAGATOR_MIN_STEP)) {
minStep = 0.001;
} else {
minStep = parser.getDouble(ParameterKey.PROPAGATOR_MIN_STEP);
}
final double maxStep;
if (!parser.containsKey(ParameterKey.PROPAGATOR_MAX_STEP)) {
maxStep = 300;
} else {
maxStep = parser.getDouble(ParameterKey.PROPAGATOR_MAX_STEP);
}
final double dP;
if (!parser.containsKey(ParameterKey.PROPAGATOR_POSITION_ERROR)) {
dP = 10.0;
} else {
dP = parser.getDouble(ParameterKey.PROPAGATOR_POSITION_ERROR);
}
final double positionScale;
if (!parser.containsKey(ParameterKey.ESTIMATOR_ORBITAL_PARAMETERS_POSITION_SCALE)) {
positionScale = dP;
} else {
positionScale = parser.getDouble(ParameterKey.ESTIMATOR_ORBITAL_PARAMETERS_POSITION_SCALE);
}
final NumericalPropagatorBuilder propagatorBuilder = new NumericalPropagatorBuilder(orbit, new DormandPrince853IntegratorBuilder(minStep, maxStep, dP), PositionAngle.MEAN, positionScale);
// initial mass
final double mass;
if (!parser.containsKey(ParameterKey.MASS)) {
mass = 1000.0;
} else {
mass = parser.getDouble(ParameterKey.MASS);
}
propagatorBuilder.setMass(mass);
// gravity field force model
propagatorBuilder.addForceModel(new HolmesFeatherstoneAttractionModel(body.getBodyFrame(), gravityField));
// ocean tides force model
if (parser.containsKey(ParameterKey.OCEAN_TIDES_DEGREE) && parser.containsKey(ParameterKey.OCEAN_TIDES_ORDER)) {
final int degree = parser.getInt(ParameterKey.OCEAN_TIDES_DEGREE);
final int order = parser.getInt(ParameterKey.OCEAN_TIDES_ORDER);
if (degree > 0 && order > 0) {
propagatorBuilder.addForceModel(new OceanTides(body.getBodyFrame(), gravityField.getAe(), gravityField.getMu(), degree, order, conventions, TimeScalesFactory.getUT1(conventions, true)));
}
}
// solid tides force model
List<CelestialBody> solidTidesBodies = new ArrayList<CelestialBody>();
if (parser.containsKey(ParameterKey.SOLID_TIDES_SUN) && parser.getBoolean(ParameterKey.SOLID_TIDES_SUN)) {
solidTidesBodies.add(CelestialBodyFactory.getSun());
}
if (parser.containsKey(ParameterKey.SOLID_TIDES_MOON) && parser.getBoolean(ParameterKey.SOLID_TIDES_MOON)) {
solidTidesBodies.add(CelestialBodyFactory.getMoon());
}
if (!solidTidesBodies.isEmpty()) {
propagatorBuilder.addForceModel(new SolidTides(body.getBodyFrame(), gravityField.getAe(), gravityField.getMu(), gravityField.getTideSystem(), conventions, TimeScalesFactory.getUT1(conventions, true), solidTidesBodies.toArray(new CelestialBody[solidTidesBodies.size()])));
}
// third body attraction
if (parser.containsKey(ParameterKey.THIRD_BODY_SUN) && parser.getBoolean(ParameterKey.THIRD_BODY_SUN)) {
propagatorBuilder.addForceModel(new ThirdBodyAttraction(CelestialBodyFactory.getSun()));
}
if (parser.containsKey(ParameterKey.THIRD_BODY_MOON) && parser.getBoolean(ParameterKey.THIRD_BODY_MOON)) {
propagatorBuilder.addForceModel(new ThirdBodyAttraction(CelestialBodyFactory.getMoon()));
}
// drag
if (parser.containsKey(ParameterKey.DRAG) && parser.getBoolean(ParameterKey.DRAG)) {
final double cd = parser.getDouble(ParameterKey.DRAG_CD);
final double area = parser.getDouble(ParameterKey.DRAG_AREA);
final boolean cdEstimated = parser.getBoolean(ParameterKey.DRAG_CD_ESTIMATED);
MarshallSolarActivityFutureEstimation msafe = new MarshallSolarActivityFutureEstimation("(?:Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)\\p{Digit}\\p{Digit}\\p{Digit}\\p{Digit}F10\\.(?:txt|TXT)", MarshallSolarActivityFutureEstimation.StrengthLevel.AVERAGE);
DataProvidersManager manager = DataProvidersManager.getInstance();
manager.feed(msafe.getSupportedNames(), msafe);
Atmosphere atmosphere = new DTM2000(msafe, CelestialBodyFactory.getSun(), body);
propagatorBuilder.addForceModel(new DragForce(atmosphere, new IsotropicDrag(area, cd)));
if (cdEstimated) {
for (final ParameterDriver driver : propagatorBuilder.getPropagationParametersDrivers().getDrivers()) {
if (driver.getName().equals(DragSensitive.DRAG_COEFFICIENT)) {
driver.setSelected(true);
}
}
}
}
// solar radiation pressure
if (parser.containsKey(ParameterKey.SOLAR_RADIATION_PRESSURE) && parser.getBoolean(ParameterKey.SOLAR_RADIATION_PRESSURE)) {
final double cr = parser.getDouble(ParameterKey.SOLAR_RADIATION_PRESSURE_CR);
final double area = parser.getDouble(ParameterKey.SOLAR_RADIATION_PRESSURE_AREA);
final boolean cREstimated = parser.getBoolean(ParameterKey.SOLAR_RADIATION_PRESSURE_CR_ESTIMATED);
propagatorBuilder.addForceModel(new SolarRadiationPressure(CelestialBodyFactory.getSun(), body.getEquatorialRadius(), new IsotropicRadiationSingleCoefficient(area, cr)));
if (cREstimated) {
for (final ParameterDriver driver : propagatorBuilder.getPropagationParametersDrivers().getDrivers()) {
if (driver.getName().equals(RadiationSensitive.REFLECTION_COEFFICIENT)) {
driver.setSelected(true);
}
}
}
}
// post-Newtonian correction force due to general relativity
if (parser.containsKey(ParameterKey.GENERAL_RELATIVITY) && parser.getBoolean(ParameterKey.GENERAL_RELATIVITY)) {
propagatorBuilder.addForceModel(new Relativity(gravityField.getMu()));
}
// extra polynomial accelerations
if (parser.containsKey(ParameterKey.POLYNOMIAL_ACCELERATION_NAME)) {
final String[] names = parser.getStringArray(ParameterKey.POLYNOMIAL_ACCELERATION_NAME);
final Vector3D[] directions = parser.getVectorArray(ParameterKey.POLYNOMIAL_ACCELERATION_DIRECTION_X, ParameterKey.POLYNOMIAL_ACCELERATION_DIRECTION_Y, ParameterKey.POLYNOMIAL_ACCELERATION_DIRECTION_Z);
final List<String>[] coefficients = parser.getStringsListArray(ParameterKey.POLYNOMIAL_ACCELERATION_COEFFICIENTS, ',');
final boolean[] estimated = parser.getBooleanArray(ParameterKey.POLYNOMIAL_ACCELERATION_ESTIMATED);
for (int i = 0; i < names.length; ++i) {
final PolynomialParametricAcceleration ppa = new PolynomialParametricAcceleration(directions[i], true, names[i], null, coefficients[i].size() - 1);
for (int k = 0; k < coefficients[i].size(); ++k) {
final ParameterDriver driver = ppa.getParameterDriver(names[i] + "[" + k + "]");
driver.setValue(Double.parseDouble(coefficients[i].get(k)));
driver.setSelected(estimated[i]);
}
propagatorBuilder.addForceModel(ppa);
}
}
return propagatorBuilder;
}
use of org.orekit.propagation.conversion.NumericalPropagatorBuilder in project Orekit by CS-SI.
the class AngularAzElTest 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 AngularAzElMeasurementCreator(context), 0.25, 3.0, 600.0);
propagator.setSlaveMode();
// Compute measurements.
double[] AzerrorsP = new double[3 * measurements.size()];
double[] AzerrorsV = new double[3 * measurements.size()];
double[] ElerrorsP = new double[3 * measurements.size()];
double[] ElerrorsV = new double[3 * measurements.size()];
int AzindexP = 0;
int AzindexV = 0;
int ElindexP = 0;
int ElindexV = 0;
for (final ObservedMeasurement<?> measurement : measurements) {
// parameter corresponding to station position offset
final GroundStation stationParameter = ((AngularAzEl) 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) {
AzerrorsP[AzindexP++] = relativeError;
} else {
ElerrorsP[ElindexP++] = relativeError;
}
} else {
if (i == 0) {
AzerrorsV[AzindexV++] = relativeError;
} else {
ElerrorsV[ElindexV++] = relativeError;
}
}
}
}
}
// median errors on Azimuth
Assert.assertEquals(0.0, new Median().evaluate(AzerrorsP), 1.1e-10);
Assert.assertEquals(0.0, new Median().evaluate(AzerrorsV), 5.7e-5);
// median errors on Elevation
Assert.assertEquals(0.0, new Median().evaluate(ElerrorsP), 3.5e-11);
Assert.assertEquals(0.0, new Median().evaluate(ElerrorsV), 1.4e-5);
}
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