Examples with LofOffset org.orekit.attitudes.LofOffset used on opensource projects

Example 31 with LofOffset

use of org.orekit.attitudes.LofOffset in project Orekit by CS-SI.

the class ImpulseManeuverTest method testInertialManeuver.

@Test
public void testInertialManeuver() throws OrekitException {
    final double mu = CelestialBodyFactory.getEarth().getGM();
    final double initialX = 7100e3;
    final double initialY = 0.0;
    final double initialZ = 1300e3;
    final double initialVx = 0;
    final double initialVy = 8000;
    final double initialVz = 1000;
    final Vector3D position = new Vector3D(initialX, initialY, initialZ);
    final Vector3D velocity = new Vector3D(initialVx, initialVy, initialVz);
    final AbsoluteDate epoch = new AbsoluteDate(2010, 1, 1, 0, 0, 0, TimeScalesFactory.getUTC());
    final TimeStampedPVCoordinates state = new TimeStampedPVCoordinates(epoch, position, velocity, Vector3D.ZERO);
    final Orbit initialOrbit = new CartesianOrbit(state, FramesFactory.getEME2000(), mu);
    final double totalPropagationTime = 0.00001;
    final double driftTimeInSec = totalPropagationTime / 2.0;
    final double deltaX = 0.01;
    final double deltaY = 0.02;
    final double deltaZ = 0.03;
    final double isp = 300;
    final Vector3D deltaV = new Vector3D(deltaX, deltaY, deltaZ);
    KeplerianPropagator propagator = new KeplerianPropagator(initialOrbit, new LofOffset(initialOrbit.getFrame(), LOFType.VNC));
    DateDetector dateDetector = new DateDetector(epoch.shiftedBy(driftTimeInSec));
    InertialProvider attitudeOverride = new InertialProvider(new Rotation(RotationOrder.XYX, RotationConvention.VECTOR_OPERATOR, 0, 0, 0));
    ImpulseManeuver<DateDetector> burnAtEpoch = new ImpulseManeuver<DateDetector>(dateDetector, attitudeOverride, deltaV, isp).withThreshold(driftTimeInSec / 4);
    propagator.addEventDetector(burnAtEpoch);
    SpacecraftState finalState = propagator.propagate(epoch.shiftedBy(totalPropagationTime));
    final double finalVxExpected = initialVx + deltaX;
    final double finalVyExpected = initialVy + deltaY;
    final double finalVzExpected = initialVz + deltaZ;
    final double maneuverTolerance = 1e-4;
    final Vector3D finalVelocity = finalState.getPVCoordinates().getVelocity();
    Assert.assertEquals(finalVxExpected, finalVelocity.getX(), maneuverTolerance);
    Assert.assertEquals(finalVyExpected, finalVelocity.getY(), maneuverTolerance);
    Assert.assertEquals(finalVzExpected, finalVelocity.getZ(), maneuverTolerance);
}

Example 32 with LofOffset

use of org.orekit.attitudes.LofOffset in project Orekit by CS-SI.

the class ImpulseManeuverTest method testBackAndForth.

@Test
public void testBackAndForth() throws OrekitException {
    final AttitudeProvider lof = new LofOffset(FramesFactory.getEME2000(), LOFType.VNC);
    final double mu = Constants.EIGEN5C_EARTH_MU;
    final AbsoluteDate iniDate = new AbsoluteDate(2003, 5, 1, 17, 30, 0.0, TimeScalesFactory.getUTC());
    final Orbit pastOrbit = new KeplerianOrbit(7e6, 1.0e-4, FastMath.toRadians(98.5), FastMath.toRadians(87.0), FastMath.toRadians(216.1807), FastMath.toRadians(319.779), PositionAngle.MEAN, FramesFactory.getEME2000(), iniDate, mu);
    final double pastMass = 2500.0;
    DateDetector dateDetector = new DateDetector(iniDate.shiftedBy(600));
    Vector3D deltaV = new Vector3D(12.0, 1.0, -4.0);
    final double isp = 300;
    ImpulseManeuver<DateDetector> maneuver = new ImpulseManeuver<DateDetector>(dateDetector, new InertialProvider(Rotation.IDENTITY), deltaV, isp).withMaxCheck(3600.0).withThreshold(1.0e-6);
    double span = 900.0;
    KeplerianPropagator forwardPropagator = new KeplerianPropagator(pastOrbit, lof, mu, pastMass);
    forwardPropagator.addEventDetector(maneuver);
    SpacecraftState futureState = forwardPropagator.propagate(pastOrbit.getDate().shiftedBy(span));
    KeplerianPropagator backwardPropagator = new KeplerianPropagator(futureState.getOrbit(), lof, mu, futureState.getMass());
    backwardPropagator.addEventDetector(maneuver);
    SpacecraftState rebuiltPast = backwardPropagator.propagate(pastOrbit.getDate());
    Assert.assertEquals(0.0, Vector3D.distance(pastOrbit.getPVCoordinates().getPosition(), rebuiltPast.getPVCoordinates().getPosition()), 2.0e-8);
    Assert.assertEquals(0.0, Vector3D.distance(pastOrbit.getPVCoordinates().getVelocity(), rebuiltPast.getPVCoordinates().getVelocity()), 2.0e-11);
    Assert.assertEquals(pastMass, rebuiltPast.getMass(), 5.0e-13);
}

Example 33 with LofOffset

use of org.orekit.attitudes.LofOffset in project Orekit by CS-SI.

the class ImpulseManeuverTest method testAdditionalStateKeplerian.

@Test
public void testAdditionalStateKeplerian() throws OrekitException {
    final double mu = CelestialBodyFactory.getEarth().getGM();
    final double initialX = 7100e3;
    final double initialY = 0.0;
    final double initialZ = 1300e3;
    final double initialVx = 0;
    final double initialVy = 8000;
    final double initialVz = 1000;
    final Vector3D position = new Vector3D(initialX, initialY, initialZ);
    final Vector3D velocity = new Vector3D(initialVx, initialVy, initialVz);
    final AbsoluteDate epoch = new AbsoluteDate(2010, 1, 1, 0, 0, 0, TimeScalesFactory.getUTC());
    final TimeStampedPVCoordinates pv = new TimeStampedPVCoordinates(epoch, position, velocity, Vector3D.ZERO);
    final Orbit initialOrbit = new CartesianOrbit(pv, FramesFactory.getEME2000(), mu);
    final double totalPropagationTime = 10;
    final double deltaX = 0.01;
    final double deltaY = 0.02;
    final double deltaZ = 0.03;
    final double isp = 300;
    final Vector3D deltaV = new Vector3D(deltaX, deltaY, deltaZ);
    final AttitudeProvider attitudeProvider = new LofOffset(initialOrbit.getFrame(), LOFType.VNC);
    final Attitude initialAttitude = attitudeProvider.getAttitude(initialOrbit, initialOrbit.getDate(), initialOrbit.getFrame());
    final SpacecraftState initialState = new SpacecraftState(initialOrbit, initialAttitude);
    KeplerianPropagator propagator = new KeplerianPropagator(initialOrbit);
    propagator.resetInitialState(initialState.addAdditionalState("testOnly", -1.0));
    DateDetector dateDetector = new DateDetector(epoch.shiftedBy(0.5 * totalPropagationTime));
    InertialProvider attitudeOverride = new InertialProvider(new Rotation(RotationOrder.XYX, RotationConvention.VECTOR_OPERATOR, 0, 0, 0));
    ImpulseManeuver<DateDetector> burnAtEpoch = new ImpulseManeuver<DateDetector>(dateDetector, attitudeOverride, deltaV, isp).withThreshold(1.0e-3);
    propagator.addEventDetector(burnAtEpoch);
    SpacecraftState finalState = propagator.propagate(epoch.shiftedBy(totalPropagationTime));
    Assert.assertEquals(1, finalState.getAdditionalStates().size());
    Assert.assertEquals(-1.0, finalState.getAdditionalState("testOnly")[0], 1.0e-15);
}

Example 34 with LofOffset

use of org.orekit.attitudes.LofOffset in project Orekit by CS-SI.

the class HarmonicParametricAccelerationTest method testEquivalentTangentialOverriddenManeuverField.

@Test
public void testEquivalentTangentialOverriddenManeuverField() throws OrekitException {
    final double mass = 2500;
    final double isp = Double.POSITIVE_INFINITY;
    final double duration = 4000;
    final double f = 400;
    final AttitudeProvider maneuverLaw = new LofOffset(initialOrbit.getFrame(), LOFType.VNC);
    ConstantThrustManeuver maneuver = new ConstantThrustManeuver(initialOrbit.getDate().shiftedBy(-10.0), duration, f, isp, Vector3D.PLUS_I);
    final AttitudeProvider accelerationLaw = new CelestialBodyPointed(initialOrbit.getFrame(), CelestialBodyFactory.getSun(), Vector3D.PLUS_K, Vector3D.PLUS_I, Vector3D.PLUS_K);
    final HarmonicParametricAcceleration lofAcceleration = new HarmonicParametricAcceleration(Vector3D.PLUS_I, maneuverLaw, "prefix", null, Double.POSITIVE_INFINITY, 1);
    lofAcceleration.getParametersDrivers()[0].setValue(f / mass);
    lofAcceleration.getParametersDrivers()[1].setValue(0.5 * FastMath.PI);
    doTestEquivalentManeuver(Decimal64Field.getInstance(), mass, maneuverLaw, maneuver, accelerationLaw, lofAcceleration, 1.0e-15);
}

Example 35 with LofOffset

use of org.orekit.attitudes.LofOffset in project Orekit by CS-SI.

the class HarmonicParametricAccelerationTest method testEquivalentTangentialManeuver.

@Test
public void testEquivalentTangentialManeuver() throws OrekitException {
    final double mass = 2500;
    final double isp = Double.POSITIVE_INFINITY;
    final double duration = 4000;
    final double f = 400;
    final AttitudeProvider commonLaw = new LofOffset(initialOrbit.getFrame(), LOFType.VNC);
    ConstantThrustManeuver maneuver = new ConstantThrustManeuver(initialOrbit.getDate().shiftedBy(-10.0), duration, f, isp, Vector3D.PLUS_I);
    final HarmonicParametricAcceleration lofAcceleration = new HarmonicParametricAcceleration(Vector3D.PLUS_I, false, "", null, Double.POSITIVE_INFINITY, 1);
    Assert.assertFalse(lofAcceleration.dependsOnPositionOnly());
    lofAcceleration.getParametersDrivers()[0].setValue(f / mass);
    lofAcceleration.getParametersDrivers()[1].setValue(0.5 * FastMath.PI);
    doTestEquivalentManeuver(mass, commonLaw, maneuver, commonLaw, lofAcceleration, 1.0e-15);
}