Examples with FieldKeplerianOrbit org.orekit.orbits.FieldKeplerianOrbit used on opensource projects

Example 31 with FieldKeplerianOrbit

use of org.orekit.orbits.FieldKeplerianOrbit 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);
    }
}

Example 32 with FieldKeplerianOrbit

use of org.orekit.orbits.FieldKeplerianOrbit in project Orekit by CS-SI.

the class BodyCenterPointingTest method doTestQDot.

private <T extends RealFieldElement<T>> void doTestQDot(final Field<T> field) throws OrekitException {
    final double ehMu = 3.9860047e14;
    final double ae = 6.378137e6;
    final double c20 = -1.08263e-3;
    final double c30 = 2.54e-6;
    final double c40 = 1.62e-6;
    final double c50 = 2.3e-7;
    final double c60 = -5.5e-7;
    // Satellite position as circular parameters
    T zero = field.getZero();
    final T a = zero.add(7178000.0);
    final T e = zero.add(7e-5);
    final T i = zero.add(FastMath.toRadians(50.));
    final T pa = zero.add(FastMath.toRadians(45.));
    final T raan = zero.add(FastMath.toRadians(270.));
    final T m = zero.add(FastMath.toRadians(5.3 - 270));
    // Computation date
    FieldAbsoluteDate<T> date_comp = new FieldAbsoluteDate<>(field, new DateComponents(2008, 04, 07), TimeComponents.H00, TimeScalesFactory.getUTC());
    // Orbit
    FieldKeplerianOrbit<T> circ = new FieldKeplerianOrbit<>(a, e, i, pa, raan, m, PositionAngle.MEAN, FramesFactory.getEME2000(), date_comp, ehMu);
    // WGS84 Earth model
    OneAxisEllipsoid earth = new OneAxisEllipsoid(Constants.WGS84_EARTH_EQUATORIAL_RADIUS, Constants.WGS84_EARTH_FLATTENING, FramesFactory.getITRF(IERSConventions.IERS_2010, true));
    // Earth center pointing attitude provider
    BodyCenterPointing earthCenterAttitudeLaw = new BodyCenterPointing(circ.getFrame(), earth);
    final FieldAbsoluteDate<T> date = FieldAbsoluteDate.getJ2000Epoch(field).shiftedBy(584.);
    final FieldVector3D<T> position = new FieldVector3D<>(zero.add(3220103.), zero.add(69623.), zero.add(6449822.));
    final FieldVector3D<T> velocity = new FieldVector3D<>(zero.add(6414.7), zero.add(-2006.), zero.add(-3180.));
    final FieldCircularOrbit<T> initialOrbit = new FieldCircularOrbit<>(new FieldPVCoordinates<>(position, velocity), FramesFactory.getEME2000(), date, ehMu);
    FieldEcksteinHechlerPropagator<T> propagator = new FieldEcksteinHechlerPropagator<>(initialOrbit, ae, ehMu, c20, c30, c40, c50, c60);
    propagator.setAttitudeProvider(earthCenterAttitudeLaw);
    List<WeightedObservedPoint> w0 = new ArrayList<WeightedObservedPoint>();
    List<WeightedObservedPoint> w1 = new ArrayList<WeightedObservedPoint>();
    List<WeightedObservedPoint> w2 = new ArrayList<WeightedObservedPoint>();
    List<WeightedObservedPoint> w3 = new ArrayList<WeightedObservedPoint>();
    for (double dt = -1; dt < 1; dt += 0.01) {
        FieldRotation<T> rP = propagator.propagate(date.shiftedBy(dt)).getAttitude().getRotation();
        w0.add(new WeightedObservedPoint(1, dt, rP.getQ0().getReal()));
        w1.add(new WeightedObservedPoint(1, dt, rP.getQ1().getReal()));
        w2.add(new WeightedObservedPoint(1, dt, rP.getQ2().getReal()));
        w3.add(new WeightedObservedPoint(1, dt, rP.getQ3().getReal()));
    }
    double q0DotRef = PolynomialCurveFitter.create(2).fit(w0)[1];
    double q1DotRef = PolynomialCurveFitter.create(2).fit(w1)[1];
    double q2DotRef = PolynomialCurveFitter.create(2).fit(w2)[1];
    double q3DotRef = PolynomialCurveFitter.create(2).fit(w3)[1];
    FieldAttitude<T> a0 = propagator.propagate(date).getAttitude();
    T q0 = a0.getRotation().getQ0();
    T q1 = a0.getRotation().getQ1();
    T q2 = a0.getRotation().getQ2();
    T q3 = a0.getRotation().getQ3();
    T oX = a0.getSpin().getX();
    T oY = a0.getSpin().getY();
    T oZ = a0.getSpin().getZ();
    // first time-derivatives of the quaternion
    double q0Dot = 0.5 * MathArrays.linearCombination(-q1.getReal(), oX.getReal(), -q2.getReal(), oY.getReal(), -q3.getReal(), oZ.getReal());
    double q1Dot = 0.5 * MathArrays.linearCombination(q0.getReal(), oX.getReal(), -q3.getReal(), oY.getReal(), q2.getReal(), oZ.getReal());
    double q2Dot = 0.5 * MathArrays.linearCombination(q3.getReal(), oX.getReal(), q0.getReal(), oY.getReal(), -q1.getReal(), oZ.getReal());
    double q3Dot = 0.5 * MathArrays.linearCombination(-q2.getReal(), oX.getReal(), q1.getReal(), oY.getReal(), q0.getReal(), oZ.getReal());
    Assert.assertEquals(q0DotRef, q0Dot, 5.0e-9);
    Assert.assertEquals(q1DotRef, q1Dot, 5.0e-9);
    Assert.assertEquals(q2DotRef, q2Dot, 5.0e-9);
    Assert.assertEquals(q3DotRef, q3Dot, 5.0e-9);
}

Example 33 with FieldKeplerianOrbit

use of org.orekit.orbits.FieldKeplerianOrbit in project Orekit by CS-SI.

the class BodyCenterPointingTest method doTestTarget.

private <T extends RealFieldElement<T>> void doTestTarget(final Field<T> field) throws OrekitException {
    double mu = 3.9860047e14;
    T zero = field.getZero();
    // Satellite position as circular parameters
    final T raan = zero.add(FastMath.toRadians(270.));
    final T a = zero.add(7178000.0);
    final T e = zero.add(7e-5);
    final T i = zero.add(FastMath.toRadians(50.));
    final T pa = zero.add(FastMath.toRadians(45.));
    final T m = zero.add(FastMath.toRadians(5.3 - 270));
    // Computation date
    FieldAbsoluteDate<T> date = new FieldAbsoluteDate<>(field, new DateComponents(2008, 04, 07), TimeComponents.H00, TimeScalesFactory.getUTC());
    // Orbit
    FieldKeplerianOrbit<T> circ = new FieldKeplerianOrbit<>(a, e, i, pa, raan, m, PositionAngle.MEAN, FramesFactory.getEME2000(), date, mu);
    // WGS84 Earth model
    OneAxisEllipsoid earth = new OneAxisEllipsoid(Constants.WGS84_EARTH_EQUATORIAL_RADIUS, Constants.WGS84_EARTH_FLATTENING, FramesFactory.getITRF(IERSConventions.IERS_2010, true));
    // Earth center pointing attitude provider
    BodyCenterPointing earthCenterAttitudeLaw = new BodyCenterPointing(circ.getFrame(), earth);
    // Call get target method
    TimeStampedFieldPVCoordinates<T> target = earthCenterAttitudeLaw.getTargetPV(circ, date, circ.getFrame());
    // Check that target is on Earth surface
    GeodeticPoint gp = earth.transform(target.getPosition().toVector3D(), circ.getFrame(), date.toAbsoluteDate());
    // less precision because i suppose we are working with Keplerian instead of circular
    Assert.assertEquals(0.0, gp.getAltitude(), 1.0e-8);
    Assert.assertEquals(date, target.getDate());
}

Example 34 with FieldKeplerianOrbit

use of org.orekit.orbits.FieldKeplerianOrbit in project Orekit by CS-SI.

the class BodyCenterPointingTest method doTestBodyCenterInPointingDirection.

private <T extends RealFieldElement<T>> void doTestBodyCenterInPointingDirection(final Field<T> field) throws OrekitException {
    double mu = 3.9860047e14;
    T zero = field.getZero();
    // Satellite position as circular parameters
    final T raan = zero.add(FastMath.toRadians(270.));
    final T a = zero.add(7178000.0);
    final T e = zero.add(7E-5);
    final T i = zero.add(FastMath.toRadians(50.));
    final T pa = zero.add(FastMath.toRadians(45.));
    final T m = zero.add(FastMath.toRadians(5.300 - 270.));
    // Computation date
    FieldAbsoluteDate<T> date = new FieldAbsoluteDate<>(field, new DateComponents(2008, 04, 07), TimeComponents.H00, TimeScalesFactory.getUTC());
    // Orbit
    FieldKeplerianOrbit<T> circ = new FieldKeplerianOrbit<>(a, e, i, pa, raan, m, PositionAngle.MEAN, FramesFactory.getEME2000(), date, mu);
    // WGS84 Earth model
    OneAxisEllipsoid earth = new OneAxisEllipsoid(Constants.WGS84_EARTH_EQUATORIAL_RADIUS, Constants.WGS84_EARTH_FLATTENING, FramesFactory.getITRF(IERSConventions.IERS_2010, true));
    // Transform from EME2000 to ITRF2008
    Transform eme2000ToItrf = FramesFactory.getEME2000().getTransformTo(earth.getBodyFrame(), date.toAbsoluteDate());
    // Earth center pointing attitude provider
    BodyCenterPointing earthCenterAttitudeLaw = new BodyCenterPointing(circ.getFrame(), earth);
    // Transform satellite position to position/velocity parameters in EME2000 frame
    FieldPVCoordinates<T> pvSatEME2000 = circ.getPVCoordinates();
    // Pointing direction
    // ********************
    // Get satellite attitude rotation, i.e rotation from EME2000 frame to satellite frame
    FieldRotation<T> rotSatEME2000 = earthCenterAttitudeLaw.getAttitude(circ, date, circ.getFrame()).getRotation();
    // checked this values with the bodycenterpointing test values
    // Transform Z axis from satellite frame to EME2000
    FieldVector3D<T> zSatEME2000 = rotSatEME2000.applyInverseTo(Vector3D.PLUS_K);
    // Transform Z axis from EME2000 to ITRF2008
    FieldVector3D<T> zSatITRF2008C = eme2000ToItrf.transformVector(zSatEME2000);
    // Transform satellite position/velocity from EME2000 to ITRF2008
    FieldPVCoordinates<T> pvSatITRF2008C = eme2000ToItrf.transformPVCoordinates(pvSatEME2000);
    // Line containing satellite point and following pointing direction
    Line pointingLine = new Line(pvSatITRF2008C.getPosition().toVector3D(), pvSatITRF2008C.getPosition().toVector3D().add(Constants.WGS84_EARTH_EQUATORIAL_RADIUS, zSatITRF2008C.toVector3D()), 2.0e-8);
    // Check that the line contains Earth center
    Assert.assertTrue(pointingLine.contains(Vector3D.ZERO));
}

Example 35 with FieldKeplerianOrbit

use of org.orekit.orbits.FieldKeplerianOrbit in project Orekit by CS-SI.

the class AttitudesSequenceTest method doTestDayNightSwitchField.

private <T extends RealFieldElement<T>> void doTestDayNightSwitchField(final Field<T> field) throws OrekitException {
    // Initial state definition : date, orbit
    final FieldAbsoluteDate<T> initialDate = new FieldAbsoluteDate<>(field, 2004, 01, 01, 23, 30, 00.000, TimeScalesFactory.getUTC());
    final FieldVector3D<T> position = new FieldVector3D<>(field, new Vector3D(-6142438.668, 3492467.560, -25767.25680));
    final FieldVector3D<T> velocity = new FieldVector3D<>(field, new Vector3D(505.8479685, 942.7809215, 7435.922231));
    final FieldOrbit<T> initialOrbit = new FieldKeplerianOrbit<>(new FieldPVCoordinates<>(position, velocity), FramesFactory.getEME2000(), initialDate, Constants.EIGEN5C_EARTH_MU);
    // Attitudes sequence definition
    EventsLogger logger = new EventsLogger();
    final AttitudesSequence attitudesSequence = new AttitudesSequence();
    final AttitudeProvider dayObservationLaw = new LofOffset(initialOrbit.getFrame(), LOFType.VVLH, RotationOrder.XYZ, FastMath.toRadians(20), FastMath.toRadians(40), 0);
    final AttitudeProvider nightRestingLaw = new LofOffset(initialOrbit.getFrame(), LOFType.VVLH);
    final PVCoordinatesProvider sun = CelestialBodyFactory.getSun();
    final PVCoordinatesProvider earth = CelestialBodyFactory.getEarth();
    final EclipseDetector ed = new EclipseDetector(sun, 696000000., earth, Constants.WGS84_EARTH_EQUATORIAL_RADIUS).withHandler(new ContinueOnEvent<EclipseDetector>() {

        private static final long serialVersionUID = 1L;

        int count = 0;

        public EventHandler.Action eventOccurred(final SpacecraftState s, final EclipseDetector d, final boolean increasing) {
            setInEclipse(s.getDate(), !increasing);
            if (count++ == 7) {
                return Action.STOP;
            } else {
                switch(count % 3) {
                    case 0:
                        return Action.CONTINUE;
                    case 1:
                        return Action.RESET_DERIVATIVES;
                    default:
                        return Action.RESET_STATE;
                }
            }
        }
    });
    final EventDetector monitored = logger.monitorDetector(ed);
    final Handler dayToNightHandler = new Handler(dayObservationLaw, nightRestingLaw);
    final Handler nightToDayHandler = new Handler(nightRestingLaw, dayObservationLaw);
    attitudesSequence.addSwitchingCondition(dayObservationLaw, nightRestingLaw, monitored, false, true, 300.0, AngularDerivativesFilter.USE_RRA, dayToNightHandler);
    attitudesSequence.addSwitchingCondition(nightRestingLaw, dayObservationLaw, monitored, true, false, 300.0, AngularDerivativesFilter.USE_RRA, nightToDayHandler);
    FieldSpacecraftState<T> initialState = new FieldSpacecraftState<>(initialOrbit);
    initialState = initialState.addAdditionalState("fortyTwo", field.getZero().add(42.0));
    if (ed.g(initialState.toSpacecraftState()) >= 0) {
        // initial position is in daytime
        setInEclipse(initialDate.toAbsoluteDate(), false);
        attitudesSequence.resetActiveProvider(dayObservationLaw);
    } else {
        // initial position is in nighttime
        setInEclipse(initialDate.toAbsoluteDate(), true);
        attitudesSequence.resetActiveProvider(nightRestingLaw);
    }
    // Propagator : consider the analytical Eckstein-Hechler model
    final FieldPropagator<T> propagator = new FieldEcksteinHechlerPropagator<T>(initialOrbit, attitudesSequence, 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);
    // Register the switching events to the propagator
    attitudesSequence.registerSwitchEvents(field, propagator);
    propagator.setMasterMode(field.getZero().add(60.0), new FieldOrekitFixedStepHandler<T>() {

        public void handleStep(FieldSpacecraftState<T> currentState, boolean isLast) throws OrekitException {
            // the Earth position in spacecraft frame should be along spacecraft Z axis
            // during night time and away from it during day time due to roll and pitch offsets
            final FieldVector3D<T> earth = currentState.toTransform().transformPosition(Vector3D.ZERO);
            final T pointingOffset = FieldVector3D.angle(earth, Vector3D.PLUS_K);
            // the g function is the eclipse indicator, its an angle between Sun and Earth limb,
            // positive when Sun is outside of Earth limb, negative when Sun is hidden by Earth limb
            final double eclipseAngle = ed.g(currentState.toSpacecraftState());
            if (currentState.getDate().durationFrom(lastChange).getReal() > 300) {
                if (inEclipse) {
                    Assert.assertTrue(eclipseAngle <= 0);
                    Assert.assertEquals(0.0, pointingOffset.getReal(), 1.0e-6);
                } else {
                    Assert.assertTrue(eclipseAngle >= 0);
                    Assert.assertEquals(0.767215, pointingOffset.getReal(), 1.0e-6);
                }
            } else {
                // we are in transition
                Assert.assertTrue(pointingOffset.getReal() + " " + (0.767215 - pointingOffset.getReal()), pointingOffset.getReal() <= 0.7672155);
            }
        }
    });
    // Propagate from the initial date for the fixed duration
    propagator.propagate(initialDate.shiftedBy(12600.));
    // as we have 2 switch events (even if they share the same underlying event detector),
    // and these events are triggered at both eclipse entry and exit, we get 8
    // raw events on 2 orbits
    Assert.assertEquals(8, logger.getLoggedEvents().size());
    // we have 4 attitudes switch on 2 orbits, 2 of each type
    Assert.assertEquals(2, dayToNightHandler.dates.size());
    Assert.assertEquals(2, nightToDayHandler.dates.size());
}