/**
* load orekit data and gravity field.
*
* @throws Exception on error.
*/
@BeforeClass
public static void setUpBefore() throws Exception {
Utils.setDataRoot("earth:geoid:regular-data");
GravityFieldFactory.clearPotentialCoefficientsReaders();
GravityFieldFactory.addPotentialCoefficientsReader(new EGMFormatReader("egm96", false));
potential = GravityFieldFactory.getConstantNormalizedProvider(maxDegree, maxOrder);
}
@Before
public void setUp() throws OrekitException {
Utils.setDataRoot("regular-data:potential/shm-format");
GravityFieldFactory.addPotentialCoefficientsReader(
new SHMFormatReader("^eigen_cg03c_coef$", false));
mu = GravityFieldFactory.getUnnormalizedProvider(0, 0).getMu();
final Vector3D position = new Vector3D(7.0e6, 1.0e6, 4.0e6);
final Vector3D velocity = new Vector3D(-500.0, 8000.0, 1000.0);
initDate = AbsoluteDate.J2000_EPOCH;
final Orbit orbit =
new EquinoctialOrbit(
new PVCoordinates(position, velocity), FramesFactory.getEME2000(), initDate, mu);
initialState = new SpacecraftState(orbit);
double[][] tolerance = NumericalPropagator.tolerances(0.001, orbit, OrbitType.EQUINOCTIAL);
AdaptiveStepsizeIntegrator integrator =
new DormandPrince853Integrator(0.001, 200, tolerance[0], tolerance[1]);
integrator.setInitialStepSize(60);
propagator = new NumericalPropagator(integrator);
propagator.setInitialState(initialState);
}
public static void clearFactories() {
OrekitUtils.clearFactoryMaps(CelestialBodyFactory.class);
CelestialBodyFactory.clearCelestialBodyLoaders();
OrekitUtils.clearFactoryMaps(FramesFactory.class);
OrekitUtils.clearFactoryMaps(TimeScalesFactory.class);
OrekitUtils.clearFactory(TimeScalesFactory.class, TimeScale.class);
OrekitUtils.clearFactoryMaps(JacobiPolynomials.class);
OrekitUtils.clearFactoryMaps(NewcombOperators.class);
for (final Class<?> c : NewcombOperators.class.getDeclaredClasses()) {
if (c.getName().endsWith("PolynomialsGenerator")) {
OrekitUtils.clearFactoryMaps(c);
}
}
// FramesFactory.setEOPContinuityThreshold(5 * Constants.JULIAN_DAY);
// TimeScalesFactory.clearUTCTAILoaders();
OrekitUtils.clearJPLEphemeridesConstants();
GravityFieldFactory.clearPotentialCoefficientsReaders();
GravityFieldFactory.clearOceanTidesReaders();
DataProvidersManager.getInstance().clearProviders();
DataProvidersManager.getInstance().clearLoadedDataNames();
}
@Test
public void testPropagationTypesHyperbolic() throws OrekitException, ParseException, IOException {
SpacecraftState state =
new SpacecraftState(
new KeplerianOrbit(
-10000000.0,
2.5,
0.3,
0,
0,
0.0,
PositionAngle.TRUE,
FramesFactory.getEME2000(),
initDate,
mu));
ForceModel gravityField =
new HolmesFeatherstoneAttractionModel(
FramesFactory.getITRF(IERSConventions.IERS_2010, true),
GravityFieldFactory.getNormalizedProvider(5, 5));
propagator.addForceModel(gravityField);
// Propagation of the initial at t + dt
final PVCoordinates pv = state.getPVCoordinates();
final double dP = 0.001;
final double dV =
state.getMu() * dP / (pv.getPosition().getNormSq() * pv.getVelocity().getNorm());
final PVCoordinates pvcM = propagateInType(state, dP, OrbitType.CARTESIAN, PositionAngle.MEAN);
final PVCoordinates pvkM = propagateInType(state, dP, OrbitType.KEPLERIAN, PositionAngle.MEAN);
final PVCoordinates pvcE =
propagateInType(state, dP, OrbitType.CARTESIAN, PositionAngle.ECCENTRIC);
final PVCoordinates pvkE =
propagateInType(state, dP, OrbitType.KEPLERIAN, PositionAngle.ECCENTRIC);
final PVCoordinates pvcT = propagateInType(state, dP, OrbitType.CARTESIAN, PositionAngle.TRUE);
final PVCoordinates pvkT = propagateInType(state, dP, OrbitType.KEPLERIAN, PositionAngle.TRUE);
Assert.assertEquals(0, pvcM.getPosition().subtract(pvkT.getPosition()).getNorm() / dP, 0.3);
Assert.assertEquals(0, pvcM.getVelocity().subtract(pvkT.getVelocity()).getNorm() / dV, 0.4);
Assert.assertEquals(0, pvkM.getPosition().subtract(pvkT.getPosition()).getNorm() / dP, 0.2);
Assert.assertEquals(0, pvkM.getVelocity().subtract(pvkT.getVelocity()).getNorm() / dV, 0.3);
Assert.assertEquals(0, pvcE.getPosition().subtract(pvkT.getPosition()).getNorm() / dP, 0.3);
Assert.assertEquals(0, pvcE.getVelocity().subtract(pvkT.getVelocity()).getNorm() / dV, 0.4);
Assert.assertEquals(0, pvkE.getPosition().subtract(pvkT.getPosition()).getNorm() / dP, 0.009);
Assert.assertEquals(0, pvkE.getVelocity().subtract(pvkT.getVelocity()).getNorm() / dV, 0.006);
Assert.assertEquals(0, pvcT.getPosition().subtract(pvkT.getPosition()).getNorm() / dP, 0.3);
Assert.assertEquals(0, pvcT.getVelocity().subtract(pvkT.getVelocity()).getNorm() / dV, 0.4);
}
@Before
public void setUp() throws OrekitException {
Utils.setDataRoot("regular-data:potential/shm-format");
GravityFieldFactory.addPotentialCoefficientsReader(
new SHMFormatReader("^eigen_cg03c_coef$", false));
}
@Test
public void testPropagationTypesElliptical() throws OrekitException, ParseException, IOException {
NormalizedSphericalHarmonicsProvider provider = GravityFieldFactory.getNormalizedProvider(5, 5);
ForceModel gravityField =
new HolmesFeatherstoneAttractionModel(
FramesFactory.getITRF(IERSConventions.IERS_2010, true), provider);
Orbit initialOrbit =
new KeplerianOrbit(
8000000.0,
0.01,
0.1,
0.7,
0,
1.2,
PositionAngle.TRUE,
FramesFactory.getEME2000(),
AbsoluteDate.J2000_EPOCH,
provider.getMu());
double dt = 900;
double dP = 0.001;
for (OrbitType orbitType : OrbitType.values()) {
for (PositionAngle angleType : PositionAngle.values()) {
// compute state Jacobian using PartialDerivatives
NumericalPropagator propagator =
setUpPropagator(initialOrbit, dP, orbitType, angleType, gravityField);
PartialDerivativesEquations partials =
new PartialDerivativesEquations("partials", propagator);
final SpacecraftState initialState =
partials.setInitialJacobians(new SpacecraftState(initialOrbit), 6, 0);
propagator.setInitialState(initialState);
final JacobiansMapper mapper = partials.getMapper();
PickUpHandler pickUp = new PickUpHandler(mapper, null);
propagator.setMasterMode(pickUp);
propagator.propagate(initialState.getDate().shiftedBy(dt));
double[][] dYdY0 = pickUp.getdYdY0();
// compute reference state Jacobian using finite differences
double[][] dYdY0Ref = new double[6][6];
AbstractIntegratedPropagator propagator2 =
setUpPropagator(initialOrbit, dP, orbitType, angleType, gravityField);
double[] steps = NumericalPropagator.tolerances(1000000 * dP, initialOrbit, orbitType)[0];
for (int i = 0; i < 6; ++i) {
propagator2.resetInitialState(
shiftState(initialState, orbitType, angleType, -4 * steps[i], i));
SpacecraftState sM4h = propagator2.propagate(initialState.getDate().shiftedBy(dt));
propagator2.resetInitialState(
shiftState(initialState, orbitType, angleType, -3 * steps[i], i));
SpacecraftState sM3h = propagator2.propagate(initialState.getDate().shiftedBy(dt));
propagator2.resetInitialState(
shiftState(initialState, orbitType, angleType, -2 * steps[i], i));
SpacecraftState sM2h = propagator2.propagate(initialState.getDate().shiftedBy(dt));
propagator2.resetInitialState(
shiftState(initialState, orbitType, angleType, -1 * steps[i], i));
SpacecraftState sM1h = propagator2.propagate(initialState.getDate().shiftedBy(dt));
propagator2.resetInitialState(
shiftState(initialState, orbitType, angleType, 1 * steps[i], i));
SpacecraftState sP1h = propagator2.propagate(initialState.getDate().shiftedBy(dt));
propagator2.resetInitialState(
shiftState(initialState, orbitType, angleType, 2 * steps[i], i));
SpacecraftState sP2h = propagator2.propagate(initialState.getDate().shiftedBy(dt));
propagator2.resetInitialState(
shiftState(initialState, orbitType, angleType, 3 * steps[i], i));
SpacecraftState sP3h = propagator2.propagate(initialState.getDate().shiftedBy(dt));
propagator2.resetInitialState(
shiftState(initialState, orbitType, angleType, 4 * steps[i], i));
SpacecraftState sP4h = propagator2.propagate(initialState.getDate().shiftedBy(dt));
fillJacobianColumn(
dYdY0Ref, i, orbitType, angleType, steps[i], sM4h, sM3h, sM2h, sM1h, sP1h, sP2h, sP3h,
sP4h);
}
for (int i = 0; i < 6; ++i) {
for (int j = 0; j < 6; ++j) {
double error = FastMath.abs((dYdY0[i][j] - dYdY0Ref[i][j]) / dYdY0Ref[i][j]);
Assert.assertEquals(0, error, 6.0e-2);
}
}
}
}
}
@Test
public void testPropagationTypesElliptical() throws OrekitException, ParseException, IOException {
ForceModel gravityField =
new HolmesFeatherstoneAttractionModel(
FramesFactory.getITRF(IERSConventions.IERS_2010, true),
GravityFieldFactory.getNormalizedProvider(5, 5));
propagator.addForceModel(gravityField);
// Propagation of the initial at t + dt
final PVCoordinates pv = initialState.getPVCoordinates();
final double dP = 0.001;
final double dV =
initialState.getMu() * dP / (pv.getPosition().getNormSq() * pv.getVelocity().getNorm());
final PVCoordinates pvcM =
propagateInType(initialState, dP, OrbitType.CARTESIAN, PositionAngle.MEAN);
final PVCoordinates pviM =
propagateInType(initialState, dP, OrbitType.CIRCULAR, PositionAngle.MEAN);
final PVCoordinates pveM =
propagateInType(initialState, dP, OrbitType.EQUINOCTIAL, PositionAngle.MEAN);
final PVCoordinates pvkM =
propagateInType(initialState, dP, OrbitType.KEPLERIAN, PositionAngle.MEAN);
final PVCoordinates pvcE =
propagateInType(initialState, dP, OrbitType.CARTESIAN, PositionAngle.ECCENTRIC);
final PVCoordinates pviE =
propagateInType(initialState, dP, OrbitType.CIRCULAR, PositionAngle.ECCENTRIC);
final PVCoordinates pveE =
propagateInType(initialState, dP, OrbitType.EQUINOCTIAL, PositionAngle.ECCENTRIC);
final PVCoordinates pvkE =
propagateInType(initialState, dP, OrbitType.KEPLERIAN, PositionAngle.ECCENTRIC);
final PVCoordinates pvcT =
propagateInType(initialState, dP, OrbitType.CARTESIAN, PositionAngle.TRUE);
final PVCoordinates pviT =
propagateInType(initialState, dP, OrbitType.CIRCULAR, PositionAngle.TRUE);
final PVCoordinates pveT =
propagateInType(initialState, dP, OrbitType.EQUINOCTIAL, PositionAngle.TRUE);
final PVCoordinates pvkT =
propagateInType(initialState, dP, OrbitType.KEPLERIAN, PositionAngle.TRUE);
Assert.assertEquals(0, pvcM.getPosition().subtract(pveT.getPosition()).getNorm() / dP, 3.0);
Assert.assertEquals(0, pvcM.getVelocity().subtract(pveT.getVelocity()).getNorm() / dV, 2.0);
Assert.assertEquals(0, pviM.getPosition().subtract(pveT.getPosition()).getNorm() / dP, 0.6);
Assert.assertEquals(0, pviM.getVelocity().subtract(pveT.getVelocity()).getNorm() / dV, 0.4);
Assert.assertEquals(0, pvkM.getPosition().subtract(pveT.getPosition()).getNorm() / dP, 0.5);
Assert.assertEquals(0, pvkM.getVelocity().subtract(pveT.getVelocity()).getNorm() / dV, 0.3);
Assert.assertEquals(0, pveM.getPosition().subtract(pveT.getPosition()).getNorm() / dP, 0.2);
Assert.assertEquals(0, pveM.getVelocity().subtract(pveT.getVelocity()).getNorm() / dV, 0.2);
Assert.assertEquals(0, pvcE.getPosition().subtract(pveT.getPosition()).getNorm() / dP, 3.0);
Assert.assertEquals(0, pvcE.getVelocity().subtract(pveT.getVelocity()).getNorm() / dV, 2.0);
Assert.assertEquals(0, pviE.getPosition().subtract(pveT.getPosition()).getNorm() / dP, 0.03);
Assert.assertEquals(0, pviE.getVelocity().subtract(pveT.getVelocity()).getNorm() / dV, 0.04);
Assert.assertEquals(0, pvkE.getPosition().subtract(pveT.getPosition()).getNorm() / dP, 0.4);
Assert.assertEquals(0, pvkE.getVelocity().subtract(pveT.getVelocity()).getNorm() / dV, 0.3);
Assert.assertEquals(0, pveE.getPosition().subtract(pveT.getPosition()).getNorm() / dP, 0.2);
Assert.assertEquals(0, pveE.getVelocity().subtract(pveT.getVelocity()).getNorm() / dV, 0.07);
Assert.assertEquals(0, pvcT.getPosition().subtract(pveT.getPosition()).getNorm() / dP, 3.0);
Assert.assertEquals(0, pvcT.getVelocity().subtract(pveT.getVelocity()).getNorm() / dV, 2.0);
Assert.assertEquals(0, pviT.getPosition().subtract(pveT.getPosition()).getNorm() / dP, 0.3);
Assert.assertEquals(0, pviT.getVelocity().subtract(pveT.getVelocity()).getNorm() / dV, 0.2);
Assert.assertEquals(0, pvkT.getPosition().subtract(pveT.getPosition()).getNorm() / dP, 0.4);
Assert.assertEquals(0, pvkT.getVelocity().subtract(pveT.getVelocity()).getNorm() / dV, 0.2);
}