use of org.orekit.forces.maneuvers.ConstantThrustManeuver in project Orekit by CS-SI.
the class PolynomialParametricAccelerationTest method doTestEquivalentManeuver.
private void doTestEquivalentManeuver(final double mass, final AttitudeProvider maneuverLaw, final ConstantThrustManeuver maneuver, final AttitudeProvider accelerationLaw, final PolynomialParametricAcceleration parametricAcceleration, final double positionTolerance) throws OrekitException {
SpacecraftState initialState = new SpacecraftState(initialOrbit, maneuverLaw.getAttitude(initialOrbit, initialOrbit.getDate(), initialOrbit.getFrame()), mass);
double[][] tolerance = NumericalPropagator.tolerances(10, initialOrbit, initialOrbit.getType());
// propagator 0 uses a maneuver that is so efficient it does not consume any fuel
// (hence mass remains constant)
AdaptiveStepsizeIntegrator integrator0 = new DormandPrince853Integrator(0.001, 100, tolerance[0], tolerance[1]);
integrator0.setInitialStepSize(60);
final NumericalPropagator propagator0 = new NumericalPropagator(integrator0);
propagator0.setInitialState(initialState);
propagator0.setAttitudeProvider(maneuverLaw);
propagator0.addForceModel(maneuver);
// propagator 1 uses a constant acceleration
AdaptiveStepsizeIntegrator integrator1 = new DormandPrince853Integrator(0.001, 100, tolerance[0], tolerance[1]);
integrator1.setInitialStepSize(60);
final NumericalPropagator propagator1 = new NumericalPropagator(integrator1);
propagator1.setInitialState(initialState);
propagator1.setAttitudeProvider(accelerationLaw);
propagator1.addForceModel(parametricAcceleration);
MultiSatStepHandler handler = (interpolators, isLast) -> {
Vector3D p0 = interpolators.get(0).getCurrentState().getPVCoordinates().getPosition();
Vector3D p1 = interpolators.get(1).getCurrentState().getPVCoordinates().getPosition();
Assert.assertEquals(0.0, Vector3D.distance(p0, p1), positionTolerance);
};
PropagatorsParallelizer parallelizer = new PropagatorsParallelizer(Arrays.asList(propagator0, propagator1), handler);
parallelizer.propagate(initialOrbit.getDate(), initialOrbit.getDate().shiftedBy(1000.0));
}
use of org.orekit.forces.maneuvers.ConstantThrustManeuver in project Orekit by CS-SI.
the class PolynomialParametricAccelerationTest 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 PolynomialParametricAcceleration lofAcceleration = new PolynomialParametricAcceleration(Vector3D.PLUS_I, maneuverLaw, "prefix", null, 0);
lofAcceleration.getParametersDrivers()[0].setValue(f / mass);
doTestEquivalentManeuver(Decimal64Field.getInstance(), mass, maneuverLaw, maneuver, accelerationLaw, lofAcceleration, 1.0e-15);
}
use of org.orekit.forces.maneuvers.ConstantThrustManeuver in project Orekit by CS-SI.
the class PolynomialParametricAccelerationTest method testEquivalentInertialManeuver.
@Test
public void testEquivalentInertialManeuver() throws OrekitException {
final double delta = FastMath.toRadians(-7.4978);
final double alpha = FastMath.toRadians(351);
final Vector3D direction = new Vector3D(alpha, delta);
final double mass = 2500;
final double isp = Double.POSITIVE_INFINITY;
final double duration = 4000;
final double f = 400;
final AttitudeProvider maneuverLaw = new InertialProvider(new Rotation(direction, Vector3D.PLUS_I));
ConstantThrustManeuver maneuver = new ConstantThrustManeuver(initialOrbit.getDate().shiftedBy(-10.0), duration, f, isp, Vector3D.PLUS_I);
final AttitudeProvider accelerationLaw = new InertialProvider(new Rotation(direction, Vector3D.PLUS_K));
final PolynomialParametricAcceleration inertialAcceleration = new PolynomialParametricAcceleration(direction, true, "", AbsoluteDate.J2000_EPOCH, 0);
Assert.assertTrue(inertialAcceleration.dependsOnPositionOnly());
inertialAcceleration.getParametersDrivers()[0].setValue(f / mass);
doTestEquivalentManeuver(mass, maneuverLaw, maneuver, accelerationLaw, inertialAcceleration, 1.0e-15);
}
use of org.orekit.forces.maneuvers.ConstantThrustManeuver in project Orekit by CS-SI.
the class PolynomialParametricAccelerationTest 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 PolynomialParametricAcceleration lofAcceleration = new PolynomialParametricAcceleration(Vector3D.PLUS_I, false, "", null, 0);
Assert.assertFalse(lofAcceleration.dependsOnPositionOnly());
lofAcceleration.getParametersDrivers()[0].setValue(f / mass);
doTestEquivalentManeuver(mass, commonLaw, maneuver, commonLaw, lofAcceleration, 1.0e-15);
}
use of org.orekit.forces.maneuvers.ConstantThrustManeuver in project Orekit by CS-SI.
the class PartialDerivativesTest method testJacobianIssue18.
@Test
public void testJacobianIssue18() throws OrekitException {
// Body mu
final double mu = 3.9860047e14;
final double isp = 318;
final double mass = 2500;
final double a = 24396159;
final double e = 0.72831215;
final double i = FastMath.toRadians(7);
final double omega = FastMath.toRadians(180);
final double OMEGA = FastMath.toRadians(261);
final double lv = 0;
final double duration = 3653.99;
final double f = 420;
final double delta = FastMath.toRadians(-7.4978);
final double alpha = FastMath.toRadians(351);
final AttitudeProvider law = new InertialProvider(new Rotation(new Vector3D(alpha, delta), Vector3D.PLUS_I));
final AbsoluteDate initDate = new AbsoluteDate(new DateComponents(2004, 01, 01), new TimeComponents(23, 30, 00.000), TimeScalesFactory.getUTC());
final Orbit orbit = new KeplerianOrbit(a, e, i, omega, OMEGA, lv, PositionAngle.TRUE, FramesFactory.getEME2000(), initDate, mu);
final SpacecraftState initialState = new SpacecraftState(orbit, law.getAttitude(orbit, orbit.getDate(), orbit.getFrame()), mass);
final AbsoluteDate fireDate = new AbsoluteDate(new DateComponents(2004, 01, 02), new TimeComponents(04, 15, 34.080), TimeScalesFactory.getUTC());
final ConstantThrustManeuver maneuver = new ConstantThrustManeuver(fireDate, duration, f, isp, Vector3D.PLUS_I);
double[] absTolerance = { 0.001, 1.0e-9, 1.0e-9, 1.0e-6, 1.0e-6, 1.0e-6, 0.001 };
double[] relTolerance = { 1.0e-7, 1.0e-4, 1.0e-4, 1.0e-7, 1.0e-7, 1.0e-7, 1.0e-7 };
AdaptiveStepsizeIntegrator integrator = new DormandPrince853Integrator(0.001, 1000, absTolerance, relTolerance);
integrator.setInitialStepSize(60);
final NumericalPropagator propagator = new NumericalPropagator(integrator);
propagator.setAttitudeProvider(law);
propagator.addForceModel(maneuver);
maneuver.getParameterDriver("thrust").setSelected(true);
propagator.setOrbitType(OrbitType.CARTESIAN);
PartialDerivativesEquations PDE = new PartialDerivativesEquations("derivatives", propagator);
Assert.assertEquals(1, PDE.getSelectedParameters().getNbParams());
propagator.setInitialState(PDE.setInitialJacobians(initialState));
final AbsoluteDate finalDate = fireDate.shiftedBy(3800);
final SpacecraftState finalorb = propagator.propagate(finalDate);
Assert.assertEquals(0, finalDate.durationFrom(finalorb.getDate()), 1.0e-11);
}
Aggregations