use of org.orekit.time.FieldAbsoluteDate in project Orekit by CS-SI.
the class FieldEventDetectorTest method doTestIssue108Analytical.
private <T extends RealFieldElement<T>> void doTestIssue108Analytical(Field<T> field) throws OrekitException {
final T zero = field.getZero();
final TimeScale utc = TimeScalesFactory.getUTC();
final FieldVector3D<T> position = new FieldVector3D<>(zero.add(-6142438.668), zero.add(3492467.56), zero.add(-25767.257));
final FieldVector3D<T> velocity = new FieldVector3D<>(zero.add(505.848), zero.add(942.781), zero.add(7435.922));
final FieldAbsoluteDate<T> date = new FieldAbsoluteDate<>(field, 2003, 9, 16, utc);
final FieldOrbit<T> orbit = new FieldCircularOrbit<>(new FieldPVCoordinates<>(position, velocity), FramesFactory.getEME2000(), date, mu);
final T step = zero.add(60.0);
final int n = 100;
FieldKeplerianPropagator<T> propagator = new FieldKeplerianPropagator<>(orbit);
GCallsCounter<T> counter = new GCallsCounter<>(zero.add(100000.0), zero.add(1.0e-6), 20, new FieldStopOnEvent<GCallsCounter<T>, T>());
propagator.addEventDetector(counter);
propagator.setMasterMode(step, new FieldOrekitFixedStepHandler<T>() {
public void handleStep(FieldSpacecraftState<T> currentState, boolean isLast) {
}
});
propagator.propagate(date.shiftedBy(step.multiply(n)));
Assert.assertEquals(n + 1, counter.getCount());
}
use of org.orekit.time.FieldAbsoluteDate in project Orekit by CS-SI.
the class FieldEventDetectorTest method doTestBasicScheduling.
private <T extends RealFieldElement<T>> void doTestBasicScheduling(Field<T> field) throws OrekitException {
final T zero = field.getZero();
final TimeScale utc = TimeScalesFactory.getUTC();
final FieldVector3D<T> position = new FieldVector3D<>(zero.add(-6142438.668), zero.add(3492467.56), zero.add(-25767.257));
final FieldVector3D<T> velocity = new FieldVector3D<>(zero.add(505.848), zero.add(942.781), zero.add(7435.922));
final FieldAbsoluteDate<T> date = new FieldAbsoluteDate<>(field, 2003, 9, 16, utc);
final FieldOrbit<T> orbit = new FieldCircularOrbit<>(new FieldPVCoordinates<>(position, velocity), FramesFactory.getEME2000(), date, mu);
FieldPropagator<T> propagator = new FieldKeplerianPropagator<>(orbit);
T stepSize = zero.add(60.0);
OutOfOrderChecker<T> checker = new OutOfOrderChecker<>(stepSize);
propagator.addEventDetector(new FieldDateDetector<>(date.shiftedBy(stepSize.multiply(5.25))).withHandler(checker));
propagator.setMasterMode(stepSize, checker);
propagator.propagate(date.shiftedBy(stepSize.multiply(10)));
Assert.assertTrue(checker.outOfOrderCallDetected());
}
use of org.orekit.time.FieldAbsoluteDate in project Orekit by CS-SI.
the class FieldApsideDetectorTest method doTestSimple.
private <T extends RealFieldElement<T>> void doTestSimple(Field<T> field) throws OrekitException {
final T zero = field.getZero();
final TimeScale utc = TimeScalesFactory.getUTC();
final FieldVector3D<T> position = new FieldVector3D<>(zero.add(-6142438.668), zero.add(3492467.56), zero.add(-25767.257));
final FieldVector3D<T> velocity = new FieldVector3D<>(zero.add(506.0), zero.add(943.0), zero.add(7450));
final FieldAbsoluteDate<T> date = new FieldAbsoluteDate<>(field, 2003, 9, 16, utc);
final FieldOrbit<T> orbit = new FieldCartesianOrbit<>(new FieldPVCoordinates<>(position, velocity), FramesFactory.getEME2000(), date, Constants.EIGEN5C_EARTH_MU);
FieldEcksteinHechlerPropagator<T> propagator = new FieldEcksteinHechlerPropagator<>(orbit, Constants.EIGEN5C_EARTH_EQUATORIAL_RADIUS, Constants.EIGEN5C_EARTH_MU, Constants.EIGEN5C_EARTH_C20, Constants.EIGEN5C_EARTH_C30, Constants.EIGEN5C_EARTH_C40, Constants.EIGEN5C_EARTH_C50, Constants.EIGEN5C_EARTH_C60);
FieldEventDetector<T> detector = new FieldApsideDetector<>(propagator.getInitialState().getOrbit()).withMaxCheck(zero.add(600.0)).withThreshold(zero.add(1.0e-12)).withHandler(new FieldContinueOnEvent<FieldApsideDetector<T>, T>());
Assert.assertEquals(600.0, detector.getMaxCheckInterval().getReal(), 1.0e-15);
Assert.assertEquals(1.0e-12, detector.getThreshold().getReal(), 1.0e-15);
Assert.assertEquals(AbstractDetector.DEFAULT_MAX_ITER, detector.getMaxIterationCount());
FieldEventsLogger<T> logger = new FieldEventsLogger<>();
propagator.addEventDetector(logger.monitorDetector(detector));
propagator.propagate(propagator.getInitialState().getOrbit().getDate().shiftedBy(Constants.JULIAN_DAY));
Assert.assertEquals(30, logger.getLoggedEvents().size());
for (FieldLoggedEvent<T> e : logger.getLoggedEvents()) {
FieldKeplerianOrbit<T> o = (FieldKeplerianOrbit<T>) OrbitType.KEPLERIAN.convertType(e.getState().getOrbit());
double expected = e.isIncreasing() ? 0.0 : FastMath.PI;
Assert.assertEquals(expected, MathUtils.normalizeAngle(o.getMeanAnomaly().getReal(), expected), 4.0e-14);
}
}
use of org.orekit.time.FieldAbsoluteDate in project Orekit by CS-SI.
the class AngularRaDec method theoreticalEvaluation.
/**
* {@inheritDoc}
*/
@Override
protected EstimatedMeasurement<AngularRaDec> theoreticalEvaluation(final int iteration, final int evaluation, final SpacecraftState[] states) throws OrekitException {
final SpacecraftState state = states[getPropagatorsIndices().get(0)];
// Right Ascension/elevation (in reference frame )derivatives are computed with respect to spacecraft state in inertial frame
// and station parameters
// ----------------------
//
// Parameters:
// - 0..2 - Position of the spacecraft in inertial frame
// - 3..5 - Velocity of the spacecraft in inertial frame
// - 6..n - station parameters (station offsets, pole, prime meridian...)
// Get the number of parameters used for derivation
// Place the selected drivers into a map
int nbParams = 6;
final Map<String, Integer> indices = new HashMap<>();
for (ParameterDriver driver : getParametersDrivers()) {
if (driver.isSelected()) {
indices.put(driver.getName(), nbParams++);
}
}
final DSFactory factory = new DSFactory(nbParams, 1);
final Field<DerivativeStructure> field = factory.getDerivativeField();
final FieldVector3D<DerivativeStructure> zero = FieldVector3D.getZero(field);
// Coordinates of the spacecraft expressed as a derivative structure
final TimeStampedFieldPVCoordinates<DerivativeStructure> pvaDS = getCoordinates(state, 0, factory);
// Transform between station and inertial frame, expressed as a derivative structure
// The components of station's position in offset frame are the 3 last derivative parameters
final AbsoluteDate downlinkDate = getDate();
final FieldAbsoluteDate<DerivativeStructure> downlinkDateDS = new FieldAbsoluteDate<>(field, downlinkDate);
final FieldTransform<DerivativeStructure> offsetToInertialDownlink = station.getOffsetToInertial(state.getFrame(), downlinkDateDS, factory, indices);
// Station position/velocity in inertial frame at end of the downlink leg
final TimeStampedFieldPVCoordinates<DerivativeStructure> stationDownlink = offsetToInertialDownlink.transformPVCoordinates(new TimeStampedFieldPVCoordinates<>(downlinkDateDS, zero, zero, zero));
// Compute propagation times
// (if state has already been set up to pre-compensate propagation delay,
// we will have delta == tauD and transitState will be the same as state)
// Downlink delay
final DerivativeStructure tauD = signalTimeOfFlight(pvaDS, stationDownlink.getPosition(), downlinkDateDS);
// Transit state
final double delta = downlinkDate.durationFrom(state.getDate());
final DerivativeStructure deltaMTauD = tauD.negate().add(delta);
final SpacecraftState transitState = state.shiftedBy(deltaMTauD.getValue());
// Transit state (re)computed with derivative structures
final TimeStampedFieldPVCoordinates<DerivativeStructure> transitStateDS = pvaDS.shiftedBy(deltaMTauD);
// Station-satellite vector expressed in inertial frame
final FieldVector3D<DerivativeStructure> staSatInertial = transitStateDS.getPosition().subtract(stationDownlink.getPosition());
// Field transform from inertial to reference frame at station's reception date
final FieldTransform<DerivativeStructure> inertialToReferenceDownlink = state.getFrame().getTransformTo(referenceFrame, downlinkDateDS);
// Station-satellite vector in reference frame
final FieldVector3D<DerivativeStructure> staSatReference = inertialToReferenceDownlink.transformPosition(staSatInertial);
// Compute right ascension and declination
final DerivativeStructure baseRightAscension = staSatReference.getAlpha();
final double twoPiWrap = MathUtils.normalizeAngle(baseRightAscension.getReal(), getObservedValue()[0]) - baseRightAscension.getReal();
final DerivativeStructure rightAscension = baseRightAscension.add(twoPiWrap);
final DerivativeStructure declination = staSatReference.getDelta();
// Prepare the estimation
final EstimatedMeasurement<AngularRaDec> estimated = new EstimatedMeasurement<>(this, iteration, evaluation, new SpacecraftState[] { transitState }, new TimeStampedPVCoordinates[] { transitStateDS.toTimeStampedPVCoordinates(), stationDownlink.toTimeStampedPVCoordinates() });
// azimuth - elevation values
estimated.setEstimatedValue(rightAscension.getValue(), declination.getValue());
// Partial derivatives of right ascension/declination in reference frame with respect to state
// (beware element at index 0 is the value, not a derivative)
final double[] raDerivatives = rightAscension.getAllDerivatives();
final double[] decDerivatives = declination.getAllDerivatives();
estimated.setStateDerivatives(0, Arrays.copyOfRange(raDerivatives, 1, 7), Arrays.copyOfRange(decDerivatives, 1, 7));
// (beware element at index 0 is the value, not a derivative)
for (final ParameterDriver driver : getParametersDrivers()) {
final Integer index = indices.get(driver.getName());
if (index != null) {
estimated.setParameterDerivatives(driver, raDerivatives[index + 1], decDerivatives[index + 1]);
}
}
return estimated;
}
use of org.orekit.time.FieldAbsoluteDate in project Orekit by CS-SI.
the class RangeRate method theoreticalEvaluation.
/**
* {@inheritDoc}
*/
@Override
protected EstimatedMeasurement<RangeRate> theoreticalEvaluation(final int iteration, final int evaluation, final SpacecraftState[] states) throws OrekitException {
final SpacecraftState state = states[getPropagatorsIndices().get(0)];
// Range-rate derivatives are computed with respect to spacecraft state in inertial frame
// and station position in station's offset frame
// -------
//
// Parameters:
// - 0..2 - Position of the spacecraft in inertial frame
// - 3..5 - Velocity of the spacecraft in inertial frame
// - 6..n - station parameters (station offsets, pole, prime meridian...)
int nbParams = 6;
final Map<String, Integer> indices = new HashMap<>();
for (ParameterDriver driver : getParametersDrivers()) {
if (driver.isSelected()) {
indices.put(driver.getName(), nbParams++);
}
}
final DSFactory factory = new DSFactory(nbParams, 1);
final Field<DerivativeStructure> field = factory.getDerivativeField();
final FieldVector3D<DerivativeStructure> zero = FieldVector3D.getZero(field);
// Coordinates of the spacecraft expressed as a derivative structure
final TimeStampedFieldPVCoordinates<DerivativeStructure> pvaDS = getCoordinates(state, 0, factory);
// transform between station and inertial frame, expressed as a derivative structure
// The components of station's position in offset frame are the 3 last derivative parameters
final AbsoluteDate downlinkDate = getDate();
final FieldAbsoluteDate<DerivativeStructure> downlinkDateDS = new FieldAbsoluteDate<>(field, downlinkDate);
final FieldTransform<DerivativeStructure> offsetToInertialDownlink = station.getOffsetToInertial(state.getFrame(), downlinkDateDS, factory, indices);
// Station position in inertial frame at end of the downlink leg
final TimeStampedFieldPVCoordinates<DerivativeStructure> stationDownlink = offsetToInertialDownlink.transformPVCoordinates(new TimeStampedFieldPVCoordinates<>(downlinkDateDS, zero, zero, zero));
// Compute propagation times
// (if state has already been set up to pre-compensate propagation delay,
// we will have delta == tauD and transitState will be the same as state)
// Downlink delay
final DerivativeStructure tauD = signalTimeOfFlight(pvaDS, stationDownlink.getPosition(), downlinkDateDS);
// Transit state
final double delta = downlinkDate.durationFrom(state.getDate());
final DerivativeStructure deltaMTauD = tauD.negate().add(delta);
final SpacecraftState transitState = state.shiftedBy(deltaMTauD.getValue());
// Transit state (re)computed with derivative structures
final TimeStampedFieldPVCoordinates<DerivativeStructure> transitPV = pvaDS.shiftedBy(deltaMTauD);
// one-way (downlink) range-rate
final EstimatedMeasurement<RangeRate> evalOneWay1 = oneWayTheoreticalEvaluation(iteration, evaluation, true, stationDownlink, transitPV, transitState, indices);
final EstimatedMeasurement<RangeRate> estimated;
if (twoway) {
// one-way (uplink) light time correction
final AbsoluteDate approxUplinkDate = downlinkDate.shiftedBy(-2 * tauD.getValue());
final FieldAbsoluteDate<DerivativeStructure> approxUplinkDateDS = new FieldAbsoluteDate<>(field, approxUplinkDate);
final FieldTransform<DerivativeStructure> offsetToInertialApproxUplink = station.getOffsetToInertial(state.getFrame(), approxUplinkDateDS, factory, indices);
final TimeStampedFieldPVCoordinates<DerivativeStructure> stationApproxUplink = offsetToInertialApproxUplink.transformPVCoordinates(new TimeStampedFieldPVCoordinates<>(approxUplinkDateDS, zero, zero, zero));
final DerivativeStructure tauU = signalTimeOfFlight(stationApproxUplink, transitPV.getPosition(), transitPV.getDate());
final TimeStampedFieldPVCoordinates<DerivativeStructure> stationUplink = stationApproxUplink.shiftedBy(transitPV.getDate().durationFrom(approxUplinkDateDS).subtract(tauU));
final EstimatedMeasurement<RangeRate> evalOneWay2 = oneWayTheoreticalEvaluation(iteration, evaluation, false, stationUplink, transitPV, transitState, indices);
// combine uplink and downlink values
estimated = new EstimatedMeasurement<>(this, iteration, evaluation, evalOneWay1.getStates(), new TimeStampedPVCoordinates[] { evalOneWay2.getParticipants()[0], evalOneWay1.getParticipants()[0], evalOneWay1.getParticipants()[1] });
estimated.setEstimatedValue(0.5 * (evalOneWay1.getEstimatedValue()[0] + evalOneWay2.getEstimatedValue()[0]));
// combine uplink and downlink partial derivatives with respect to state
final double[][] sd1 = evalOneWay1.getStateDerivatives(0);
final double[][] sd2 = evalOneWay2.getStateDerivatives(0);
final double[][] sd = new double[sd1.length][sd1[0].length];
for (int i = 0; i < sd.length; ++i) {
for (int j = 0; j < sd[0].length; ++j) {
sd[i][j] = 0.5 * (sd1[i][j] + sd2[i][j]);
}
}
estimated.setStateDerivatives(0, sd);
// combine uplink and downlink partial derivatives with respect to parameters
evalOneWay1.getDerivativesDrivers().forEach(driver -> {
final double[] pd1 = evalOneWay1.getParameterDerivatives(driver);
final double[] pd2 = evalOneWay2.getParameterDerivatives(driver);
final double[] pd = new double[pd1.length];
for (int i = 0; i < pd.length; ++i) {
pd[i] = 0.5 * (pd1[i] + pd2[i]);
}
estimated.setParameterDerivatives(driver, pd);
});
} else {
estimated = evalOneWay1;
}
return estimated;
}
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