use of org.hipparchus.random.UncorrelatedRandomVectorGenerator in project Orekit by CS-SI.
the class DragForceTest method RealFieldTest.
/**
*Testing if the propagation between the FieldPropagation and the propagation
* is equivalent.
* Also testing if propagating X+dX with the propagation is equivalent to
* propagation X with the FieldPropagation and then applying the taylor
* expansion of dX to the result.
*/
@Test
public void RealFieldTest() throws OrekitException {
DSFactory factory = new DSFactory(6, 4);
DerivativeStructure a_0 = factory.variable(0, 7e6);
DerivativeStructure e_0 = factory.variable(1, 0.01);
DerivativeStructure i_0 = factory.variable(2, 1.2);
DerivativeStructure R_0 = factory.variable(3, 0.7);
DerivativeStructure O_0 = factory.variable(4, 0.5);
DerivativeStructure n_0 = factory.variable(5, 0.1);
Field<DerivativeStructure> field = a_0.getField();
DerivativeStructure zero = field.getZero();
FieldAbsoluteDate<DerivativeStructure> J2000 = new FieldAbsoluteDate<>(field);
Frame EME = FramesFactory.getEME2000();
FieldKeplerianOrbit<DerivativeStructure> FKO = new FieldKeplerianOrbit<>(a_0, e_0, i_0, R_0, O_0, n_0, PositionAngle.MEAN, EME, J2000, Constants.EIGEN5C_EARTH_MU);
FieldSpacecraftState<DerivativeStructure> initialState = new FieldSpacecraftState<>(FKO);
SpacecraftState iSR = initialState.toSpacecraftState();
ClassicalRungeKuttaFieldIntegrator<DerivativeStructure> integrator = new ClassicalRungeKuttaFieldIntegrator<>(field, zero.add(6));
ClassicalRungeKuttaIntegrator RIntegrator = new ClassicalRungeKuttaIntegrator(6);
OrbitType type = OrbitType.EQUINOCTIAL;
FieldNumericalPropagator<DerivativeStructure> FNP = new FieldNumericalPropagator<>(field, integrator);
FNP.setOrbitType(type);
FNP.setInitialState(initialState);
NumericalPropagator NP = new NumericalPropagator(RIntegrator);
NP.setOrbitType(type);
NP.setInitialState(iSR);
final DragForce forceModel = new DragForce(new HarrisPriester(CelestialBodyFactory.getSun(), new OneAxisEllipsoid(Constants.WGS84_EARTH_EQUATORIAL_RADIUS, Constants.WGS84_EARTH_FLATTENING, FramesFactory.getITRF(IERSConventions.IERS_2010, true))), new BoxAndSolarArraySpacecraft(1.5, 2.0, 1.8, CelestialBodyFactory.getSun(), 20.0, Vector3D.PLUS_J, 1.2, 0.7, 0.2));
FNP.addForceModel(forceModel);
NP.addForceModel(forceModel);
FieldAbsoluteDate<DerivativeStructure> target = J2000.shiftedBy(1000.);
FieldSpacecraftState<DerivativeStructure> finalState_DS = FNP.propagate(target);
SpacecraftState finalState_R = NP.propagate(target.toAbsoluteDate());
FieldPVCoordinates<DerivativeStructure> finPVC_DS = finalState_DS.getPVCoordinates();
PVCoordinates finPVC_R = finalState_R.getPVCoordinates();
Assert.assertEquals(finPVC_DS.toPVCoordinates().getPosition().getX(), finPVC_R.getPosition().getX(), FastMath.abs(finPVC_R.getPosition().getX()) * 1e-11);
Assert.assertEquals(finPVC_DS.toPVCoordinates().getPosition().getY(), finPVC_R.getPosition().getY(), FastMath.abs(finPVC_R.getPosition().getY()) * 1e-11);
Assert.assertEquals(finPVC_DS.toPVCoordinates().getPosition().getZ(), finPVC_R.getPosition().getZ(), FastMath.abs(finPVC_R.getPosition().getZ()) * 1e-11);
long number = 23091991;
RandomGenerator RG = new Well19937a(number);
GaussianRandomGenerator NGG = new GaussianRandomGenerator(RG);
UncorrelatedRandomVectorGenerator URVG = new UncorrelatedRandomVectorGenerator(new double[] { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }, new double[] { 1e3, 0.005, 0.005, 0.01, 0.01, 0.01 }, NGG);
double a_R = a_0.getReal();
double e_R = e_0.getReal();
double i_R = i_0.getReal();
double R_R = R_0.getReal();
double O_R = O_0.getReal();
double n_R = n_0.getReal();
for (int ii = 0; ii < 1; ii++) {
double[] rand_next = URVG.nextVector();
double a_shift = a_R + rand_next[0];
double e_shift = e_R + rand_next[1];
double i_shift = i_R + rand_next[2];
double R_shift = R_R + rand_next[3];
double O_shift = O_R + rand_next[4];
double n_shift = n_R + rand_next[5];
KeplerianOrbit shiftedOrb = new KeplerianOrbit(a_shift, e_shift, i_shift, R_shift, O_shift, n_shift, PositionAngle.MEAN, EME, J2000.toAbsoluteDate(), Constants.EIGEN5C_EARTH_MU);
SpacecraftState shift_iSR = new SpacecraftState(shiftedOrb);
NumericalPropagator shift_NP = new NumericalPropagator(RIntegrator);
shift_NP.setInitialState(shift_iSR);
shift_NP.addForceModel(forceModel);
SpacecraftState finalState_shift = shift_NP.propagate(target.toAbsoluteDate());
PVCoordinates finPVC_shift = finalState_shift.getPVCoordinates();
// position check
FieldVector3D<DerivativeStructure> pos_DS = finPVC_DS.getPosition();
double x_DS = pos_DS.getX().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double y_DS = pos_DS.getY().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double z_DS = pos_DS.getZ().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
// System.out.println(pos_DS.getX().getPartialDerivative(1));
double x = finPVC_shift.getPosition().getX();
double y = finPVC_shift.getPosition().getY();
double z = finPVC_shift.getPosition().getZ();
Assert.assertEquals(x_DS, x, FastMath.abs(x - pos_DS.getX().getReal()) * 1e-5);
Assert.assertEquals(y_DS, y, FastMath.abs(y - pos_DS.getY().getReal()) * 1e-5);
Assert.assertEquals(z_DS, z, FastMath.abs(z - pos_DS.getZ().getReal()) * 1e-5);
// velocity check
FieldVector3D<DerivativeStructure> vel_DS = finPVC_DS.getVelocity();
double vx_DS = vel_DS.getX().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double vy_DS = vel_DS.getY().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double vz_DS = vel_DS.getZ().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double vx = finPVC_shift.getVelocity().getX();
double vy = finPVC_shift.getVelocity().getY();
double vz = finPVC_shift.getVelocity().getZ();
Assert.assertEquals(vx_DS, vx, FastMath.abs(vx) * 1e-7);
Assert.assertEquals(vy_DS, vy, FastMath.abs(vy) * 1e-7);
Assert.assertEquals(vz_DS, vz, FastMath.abs(vz) * 1e-7);
// acceleration check
FieldVector3D<DerivativeStructure> acc_DS = finPVC_DS.getAcceleration();
double ax_DS = acc_DS.getX().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double ay_DS = acc_DS.getY().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double az_DS = acc_DS.getZ().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double ax = finPVC_shift.getAcceleration().getX();
double ay = finPVC_shift.getAcceleration().getY();
double az = finPVC_shift.getAcceleration().getZ();
Assert.assertEquals(ax_DS, ax, FastMath.abs(ax) * 1e-5);
Assert.assertEquals(ay_DS, ay, FastMath.abs(ay) * 1e-5);
Assert.assertEquals(az_DS, az, FastMath.abs(az) * 1e-5);
}
}
use of org.hipparchus.random.UncorrelatedRandomVectorGenerator in project Orekit by CS-SI.
the class HolmesFeatherstoneAttractionModelTest method RealFieldTest.
/**
*Testing if the propagation between the FieldPropagation and the propagation
* is equivalent.
* Also testing if propagating X+dX with the propagation is equivalent to
* propagation X with the FieldPropagation and then applying the taylor
* expansion of dX to the result.
*/
@Test
public void RealFieldTest() throws OrekitException {
DSFactory factory = new DSFactory(6, 4);
DerivativeStructure a_0 = factory.variable(0, 7201009.7124401);
DerivativeStructure e_0 = factory.variable(1, 1e-3);
DerivativeStructure i_0 = factory.variable(2, 98.7 * FastMath.PI / 180);
DerivativeStructure R_0 = factory.variable(3, 15.0 * 22.5 * FastMath.PI / 180);
DerivativeStructure O_0 = factory.variable(4, 93.0 * FastMath.PI / 180);
DerivativeStructure n_0 = factory.variable(5, 0.1);
Field<DerivativeStructure> field = a_0.getField();
DerivativeStructure zero = field.getZero();
FieldAbsoluteDate<DerivativeStructure> J2000 = new FieldAbsoluteDate<>(field);
Frame EME = FramesFactory.getEME2000();
FieldKeplerianOrbit<DerivativeStructure> FKO = new FieldKeplerianOrbit<>(a_0, e_0, i_0, R_0, O_0, n_0, PositionAngle.MEAN, EME, J2000, Constants.EIGEN5C_EARTH_MU);
FieldSpacecraftState<DerivativeStructure> initialState = new FieldSpacecraftState<>(FKO);
SpacecraftState iSR = initialState.toSpacecraftState();
OrbitType type = OrbitType.EQUINOCTIAL;
double[][] tolerance = NumericalPropagator.tolerances(10.0, FKO.toOrbit(), type);
AdaptiveStepsizeFieldIntegrator<DerivativeStructure> integrator = new DormandPrince853FieldIntegrator<>(field, 0.001, 200, tolerance[0], tolerance[1]);
integrator.setInitialStepSize(zero.add(60));
AdaptiveStepsizeIntegrator RIntegrator = new DormandPrince853Integrator(0.001, 200, tolerance[0], tolerance[1]);
RIntegrator.setInitialStepSize(60);
FieldNumericalPropagator<DerivativeStructure> FNP = new FieldNumericalPropagator<>(field, integrator);
FNP.setOrbitType(type);
FNP.setInitialState(initialState);
NumericalPropagator NP = new NumericalPropagator(RIntegrator);
NP.setOrbitType(type);
NP.setInitialState(iSR);
double[][] c = new double[3][1];
c[0][0] = 0.0;
c[2][0] = normalizedC20;
double[][] s = new double[3][1];
NormalizedSphericalHarmonicsProvider provider = GravityFieldFactory.getNormalizedProvider(6378136.460, mu, TideSystem.UNKNOWN, c, s);
HolmesFeatherstoneAttractionModel forceModel = new HolmesFeatherstoneAttractionModel(itrf, provider);
FNP.addForceModel(forceModel);
NP.addForceModel(forceModel);
FieldAbsoluteDate<DerivativeStructure> target = J2000.shiftedBy(1005.);
FieldSpacecraftState<DerivativeStructure> finalState_DS = FNP.propagate(target);
SpacecraftState finalState_R = NP.propagate(target.toAbsoluteDate());
FieldPVCoordinates<DerivativeStructure> finPVC_DS = finalState_DS.getPVCoordinates();
PVCoordinates finPVC_R = finalState_R.getPVCoordinates();
Assert.assertEquals(finPVC_DS.toPVCoordinates().getPosition().getX(), finPVC_R.getPosition().getX(), FastMath.abs(finPVC_R.getPosition().getX()) * 1e-11);
Assert.assertEquals(finPVC_DS.toPVCoordinates().getPosition().getY(), finPVC_R.getPosition().getY(), FastMath.abs(finPVC_R.getPosition().getY()) * 1e-11);
Assert.assertEquals(finPVC_DS.toPVCoordinates().getPosition().getZ(), finPVC_R.getPosition().getZ(), FastMath.abs(finPVC_R.getPosition().getZ()) * 1e-11);
long number = 23091991;
RandomGenerator RG = new Well19937a(number);
GaussianRandomGenerator NGG = new GaussianRandomGenerator(RG);
UncorrelatedRandomVectorGenerator URVG = new UncorrelatedRandomVectorGenerator(new double[] { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }, new double[] { 1e1, 0.001, 0.001, 0.001, 0.001, 0.001 }, NGG);
double a_R = a_0.getReal();
double e_R = e_0.getReal();
double i_R = i_0.getReal();
double R_R = R_0.getReal();
double O_R = O_0.getReal();
double n_R = n_0.getReal();
for (int ii = 0; ii < 1; ii++) {
double[] rand_next = URVG.nextVector();
double a_shift = a_R + rand_next[0];
double e_shift = e_R + rand_next[1];
double i_shift = i_R + rand_next[2];
double R_shift = R_R + rand_next[3];
double O_shift = O_R + rand_next[4];
double n_shift = n_R + rand_next[5];
KeplerianOrbit shiftedOrb = new KeplerianOrbit(a_shift, e_shift, i_shift, R_shift, O_shift, n_shift, PositionAngle.MEAN, EME, J2000.toAbsoluteDate(), Constants.EIGEN5C_EARTH_MU);
SpacecraftState shift_iSR = new SpacecraftState(shiftedOrb);
NumericalPropagator shift_NP = new NumericalPropagator(RIntegrator);
shift_NP.setOrbitType(type);
shift_NP.setInitialState(shift_iSR);
shift_NP.addForceModel(forceModel);
SpacecraftState finalState_shift = shift_NP.propagate(target.toAbsoluteDate());
PVCoordinates finPVC_shift = finalState_shift.getPVCoordinates();
// position check
FieldVector3D<DerivativeStructure> pos_DS = finPVC_DS.getPosition();
double x_DS = pos_DS.getX().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double y_DS = pos_DS.getY().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double z_DS = pos_DS.getZ().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double x = finPVC_shift.getPosition().getX();
double y = finPVC_shift.getPosition().getY();
double z = finPVC_shift.getPosition().getZ();
Assert.assertEquals(x_DS, x, FastMath.abs(x - pos_DS.getX().getReal()) * 1e-8);
Assert.assertEquals(y_DS, y, FastMath.abs(y - pos_DS.getY().getReal()) * 1e-8);
Assert.assertEquals(z_DS, z, FastMath.abs(z - pos_DS.getZ().getReal()) * 1e-8);
// velocity check
FieldVector3D<DerivativeStructure> vel_DS = finPVC_DS.getVelocity();
double vx_DS = vel_DS.getX().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double vy_DS = vel_DS.getY().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double vz_DS = vel_DS.getZ().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double vx = finPVC_shift.getVelocity().getX();
double vy = finPVC_shift.getVelocity().getY();
double vz = finPVC_shift.getVelocity().getZ();
Assert.assertEquals(vx_DS, vx, FastMath.abs(vx) * 1e-9);
Assert.assertEquals(vy_DS, vy, FastMath.abs(vy) * 1e-9);
Assert.assertEquals(vz_DS, vz, FastMath.abs(vz) * 1e-9);
// acceleration check
FieldVector3D<DerivativeStructure> acc_DS = finPVC_DS.getAcceleration();
double ax_DS = acc_DS.getX().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double ay_DS = acc_DS.getY().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double az_DS = acc_DS.getZ().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double ax = finPVC_shift.getAcceleration().getX();
double ay = finPVC_shift.getAcceleration().getY();
double az = finPVC_shift.getAcceleration().getZ();
Assert.assertEquals(ax_DS, ax, FastMath.abs(ax) * 1e-9);
Assert.assertEquals(ay_DS, ay, FastMath.abs(ay) * 1e-9);
Assert.assertEquals(az_DS, az, FastMath.abs(az) * 1e-9);
}
}
use of org.hipparchus.random.UncorrelatedRandomVectorGenerator in project Orekit by CS-SI.
the class FieldPropagation method main.
/**
* Program entry point.
* @param args program arguments (unused here)
* @throws IOException
* @throws OrekitException
*/
public static void main(String[] args) throws IOException, OrekitException {
// the goal of this example is to make a Montecarlo simulation giving an error on the semiaxis,
// the inclination and the RAAN. The interest of doing it with Orekit based on the
// DerivativeStructure is that instead of doing a large number of propagation around the initial
// point we will do a single propagation of the initial state, and thanks to the Taylor expansion
// we will see the evolution of the std deviation of the position, which is divided in the
// CrossTrack, the LongTrack and the Radial error.
// configure Orekit
File home = new File(System.getProperty("user.home"));
File orekitData = new File(home, "orekit-data");
if (!orekitData.exists()) {
System.err.format(Locale.US, "Failed to find %s folder%n", orekitData.getAbsolutePath());
System.err.format(Locale.US, "You need to download %s from the %s page and unzip it in %s for this tutorial to work%n", "orekit-data.zip", "https://www.orekit.org/forge/projects/orekit/files", home.getAbsolutePath());
System.exit(1);
}
DataProvidersManager manager = DataProvidersManager.getInstance();
manager.addProvider(new DirectoryCrawler(orekitData));
// output file in user's home directory
File workingDir = new File(System.getProperty("user.home"));
File errorFile = new File(workingDir, "error.txt");
System.out.println("Output file is in : " + errorFile.getAbsolutePath());
PrintWriter PW = new PrintWriter(errorFile, "UTF-8");
PW.printf("time \t\tCrossTrackErr \tLongTrackErr \tRadialErr \tTotalErr%n");
// setting the parameters of the simulation
// Order of derivation of the DerivativeStructures
int params = 3;
int order = 3;
DSFactory factory = new DSFactory(params, order);
// number of samples of the montecarlo simulation
int montecarlo_size = 100;
// nominal values of the Orbital parameters
double a_nominal = 7.278E6;
double e_nominal = 1e-3;
double i_nominal = FastMath.toRadians(98.3);
double pa_nominal = FastMath.PI / 2;
double raan_nominal = 0.0;
double ni_nominal = 0.0;
// mean of the gaussian curve for each of the errors around the nominal values
// {a, i, RAAN}
double[] mean = { 0, 0, 0 };
// standard deviation of the gaussian curve for each of the errors around the nominal values
// {dA, dI, dRaan}
double[] dAdIdRaan = { 5, FastMath.toRadians(1e-3), FastMath.toRadians(1e-3) };
// time of integration
double final_Dt = 1 * 60 * 60;
// number of steps per orbit
double num_step_orbit = 10;
DerivativeStructure a_0 = factory.variable(0, a_nominal);
DerivativeStructure e_0 = factory.constant(e_nominal);
DerivativeStructure i_0 = factory.variable(1, i_nominal);
DerivativeStructure pa_0 = factory.constant(pa_nominal);
DerivativeStructure raan_0 = factory.variable(2, raan_nominal);
DerivativeStructure ni_0 = factory.constant(ni_nominal);
// sometimes we will need the field of the DerivativeStructure to build new instances
Field<DerivativeStructure> field = a_0.getField();
// sometimes we will need the zero of the DerivativeStructure to build new instances
DerivativeStructure zero = field.getZero();
// initializing the FieldAbsoluteDate with only the field it will generate the day J2000
FieldAbsoluteDate<DerivativeStructure> date_0 = new FieldAbsoluteDate<>(field);
// initialize a basic frame
Frame frame = FramesFactory.getEME2000();
// initialize the orbit
double mu = 3.9860047e14;
FieldKeplerianOrbit<DerivativeStructure> KO = new FieldKeplerianOrbit<>(a_0, e_0, i_0, pa_0, raan_0, ni_0, PositionAngle.ECCENTRIC, frame, date_0, mu);
// step of integration (how many times per orbit we take the mesures)
double int_step = KO.getKeplerianPeriod().getReal() / num_step_orbit;
// random generator to conduct an
long number = 23091991;
RandomGenerator RG = new Well19937a(number);
GaussianRandomGenerator NGG = new GaussianRandomGenerator(RG);
UncorrelatedRandomVectorGenerator URVG = new UncorrelatedRandomVectorGenerator(mean, dAdIdRaan, NGG);
double[][] rand_gen = new double[montecarlo_size][3];
for (int jj = 0; jj < montecarlo_size; jj++) {
rand_gen[jj] = URVG.nextVector();
}
//
FieldSpacecraftState<DerivativeStructure> SS_0 = new FieldSpacecraftState<>(KO);
// adding force models
ForceModel fModel_Sun = new ThirdBodyAttraction(CelestialBodyFactory.getSun());
ForceModel fModel_Moon = new ThirdBodyAttraction(CelestialBodyFactory.getMoon());
ForceModel fModel_HFAM = new HolmesFeatherstoneAttractionModel(FramesFactory.getITRF(IERSConventions.IERS_2010, true), GravityFieldFactory.getNormalizedProvider(18, 18));
// setting an hipparchus field integrator
OrbitType type = OrbitType.CARTESIAN;
double[][] tolerance = NumericalPropagator.tolerances(0.001, KO.toOrbit(), type);
AdaptiveStepsizeFieldIntegrator<DerivativeStructure> integrator = new DormandPrince853FieldIntegrator<>(field, 0.001, 200, tolerance[0], tolerance[1]);
integrator.setInitialStepSize(zero.add(60));
// setting of the field propagator, we used the numerical one in order to add the third body attraction
// and the holmes featherstone force models
FieldNumericalPropagator<DerivativeStructure> numProp = new FieldNumericalPropagator<>(field, integrator);
numProp.setOrbitType(type);
numProp.setInitialState(SS_0);
numProp.addForceModel(fModel_Sun);
numProp.addForceModel(fModel_Moon);
numProp.addForceModel(fModel_HFAM);
// with the master mode we will calulcate and print the error on every fixed step on the file error.txt
// we defined the StepHandler to do that giving him the random number generator,
// the size of the montecarlo simulation and the initial date
numProp.setMasterMode(zero.add(int_step), new MyStepHandler<DerivativeStructure>(rand_gen, montecarlo_size, date_0, PW));
//
long START = System.nanoTime();
FieldSpacecraftState<DerivativeStructure> finalState = numProp.propagate(date_0.shiftedBy(final_Dt));
long STOP = System.nanoTime();
System.out.println((STOP - START) / 1E6 + " ms");
System.out.println(finalState.getDate());
PW.close();
}
use of org.hipparchus.random.UncorrelatedRandomVectorGenerator in project Orekit by CS-SI.
the class ConstantThrustManeuverTest method RealFieldTest.
/**
*Testing if the propagation between the FieldPropagation and the propagation
* is equivalent.
* Also testing if propagating X+dX with the propagation is equivalent to
* propagation X with the FieldPropagation and then applying the taylor
* expansion of dX to the result.
*/
@Test
public void RealFieldTest() throws OrekitException {
DSFactory factory = new DSFactory(6, 5);
DerivativeStructure a_0 = factory.variable(0, 7e7);
DerivativeStructure e_0 = factory.variable(1, 0.4);
DerivativeStructure i_0 = factory.variable(2, 85 * FastMath.PI / 180);
DerivativeStructure R_0 = factory.variable(3, 0.7);
DerivativeStructure O_0 = factory.variable(4, 0.5);
DerivativeStructure n_0 = factory.variable(5, 0.1);
Field<DerivativeStructure> field = a_0.getField();
DerivativeStructure zero = field.getZero();
FieldAbsoluteDate<DerivativeStructure> J2000 = new FieldAbsoluteDate<>(field);
Frame EME = FramesFactory.getEME2000();
FieldKeplerianOrbit<DerivativeStructure> FKO = new FieldKeplerianOrbit<>(a_0, e_0, i_0, R_0, O_0, n_0, PositionAngle.MEAN, EME, J2000, Constants.EIGEN5C_EARTH_MU);
FieldSpacecraftState<DerivativeStructure> initialState = new FieldSpacecraftState<>(FKO);
SpacecraftState iSR = initialState.toSpacecraftState();
final OrbitType type = OrbitType.KEPLERIAN;
double[][] tolerance = NumericalPropagator.tolerances(10.0, FKO.toOrbit(), type);
AdaptiveStepsizeFieldIntegrator<DerivativeStructure> integrator = new DormandPrince853FieldIntegrator<>(field, 0.001, 200, tolerance[0], tolerance[1]);
integrator.setInitialStepSize(zero.add(60));
AdaptiveStepsizeIntegrator RIntegrator = new DormandPrince853Integrator(0.001, 200, tolerance[0], tolerance[1]);
RIntegrator.setInitialStepSize(60);
FieldNumericalPropagator<DerivativeStructure> FNP = new FieldNumericalPropagator<>(field, integrator);
FNP.setOrbitType(type);
FNP.setInitialState(initialState);
NumericalPropagator NP = new NumericalPropagator(RIntegrator);
NP.setOrbitType(type);
NP.setInitialState(iSR);
final ConstantThrustManeuver forceModel = new ConstantThrustManeuver(J2000.toAbsoluteDate().shiftedBy(100), 100.0, 400.0, 300.0, Vector3D.PLUS_K);
FNP.addForceModel(forceModel);
NP.addForceModel(forceModel);
FieldAbsoluteDate<DerivativeStructure> target = J2000.shiftedBy(1000.);
FieldSpacecraftState<DerivativeStructure> finalState_DS = FNP.propagate(target);
SpacecraftState finalState_R = NP.propagate(target.toAbsoluteDate());
FieldPVCoordinates<DerivativeStructure> finPVC_DS = finalState_DS.getPVCoordinates();
PVCoordinates finPVC_R = finalState_R.getPVCoordinates();
Assert.assertEquals(finPVC_DS.toPVCoordinates().getPosition().getX(), finPVC_R.getPosition().getX(), FastMath.abs(finPVC_R.getPosition().getX()) * 1e-11);
Assert.assertEquals(finPVC_DS.toPVCoordinates().getPosition().getY(), finPVC_R.getPosition().getY(), FastMath.abs(finPVC_R.getPosition().getY()) * 1e-11);
Assert.assertEquals(finPVC_DS.toPVCoordinates().getPosition().getZ(), finPVC_R.getPosition().getZ(), FastMath.abs(finPVC_R.getPosition().getZ()) * 1e-11);
long number = 23091991;
RandomGenerator RG = new Well19937a(number);
GaussianRandomGenerator NGG = new GaussianRandomGenerator(RG);
UncorrelatedRandomVectorGenerator URVG = new UncorrelatedRandomVectorGenerator(new double[] { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }, new double[] { 1e3, 0.01, 0.01, 0.01, 0.01, 0.01 }, NGG);
double a_R = a_0.getReal();
double e_R = e_0.getReal();
double i_R = i_0.getReal();
double R_R = R_0.getReal();
double O_R = O_0.getReal();
double n_R = n_0.getReal();
for (int ii = 0; ii < 1; ii++) {
double[] rand_next = URVG.nextVector();
double a_shift = a_R + rand_next[0];
double e_shift = e_R + rand_next[1];
double i_shift = i_R + rand_next[2];
double R_shift = R_R + rand_next[3];
double O_shift = O_R + rand_next[4];
double n_shift = n_R + rand_next[5];
KeplerianOrbit shiftedOrb = new KeplerianOrbit(a_shift, e_shift, i_shift, R_shift, O_shift, n_shift, PositionAngle.MEAN, EME, J2000.toAbsoluteDate(), Constants.EIGEN5C_EARTH_MU);
SpacecraftState shift_iSR = new SpacecraftState(shiftedOrb);
NumericalPropagator shift_NP = new NumericalPropagator(RIntegrator);
shift_NP.setInitialState(shift_iSR);
shift_NP.addForceModel(forceModel);
SpacecraftState finalState_shift = shift_NP.propagate(target.toAbsoluteDate());
PVCoordinates finPVC_shift = finalState_shift.getPVCoordinates();
// position check
FieldVector3D<DerivativeStructure> pos_DS = finPVC_DS.getPosition();
double x_DS = pos_DS.getX().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double y_DS = pos_DS.getY().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double z_DS = pos_DS.getZ().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
// System.out.println(pos_DS.getX().getPartialDerivative(1));
double x = finPVC_shift.getPosition().getX();
double y = finPVC_shift.getPosition().getY();
double z = finPVC_shift.getPosition().getZ();
Assert.assertEquals(x_DS, x, FastMath.abs(x - pos_DS.getX().getReal()) * 1e-8);
Assert.assertEquals(y_DS, y, FastMath.abs(y - pos_DS.getY().getReal()) * 1e-8);
Assert.assertEquals(z_DS, z, FastMath.abs(z - pos_DS.getZ().getReal()) * 1e-8);
// velocity check
FieldVector3D<DerivativeStructure> vel_DS = finPVC_DS.getVelocity();
double vx_DS = vel_DS.getX().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double vy_DS = vel_DS.getY().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double vz_DS = vel_DS.getZ().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double vx = finPVC_shift.getVelocity().getX();
double vy = finPVC_shift.getVelocity().getY();
double vz = finPVC_shift.getVelocity().getZ();
Assert.assertEquals(vx_DS, vx, FastMath.abs(vx) * 1e-9);
Assert.assertEquals(vy_DS, vy, FastMath.abs(vy) * 1e-9);
Assert.assertEquals(vz_DS, vz, FastMath.abs(vz) * 1e-9);
// acceleration check
FieldVector3D<DerivativeStructure> acc_DS = finPVC_DS.getAcceleration();
double ax_DS = acc_DS.getX().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double ay_DS = acc_DS.getY().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double az_DS = acc_DS.getZ().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double ax = finPVC_shift.getAcceleration().getX();
double ay = finPVC_shift.getAcceleration().getY();
double az = finPVC_shift.getAcceleration().getZ();
Assert.assertEquals(ax_DS, ax, FastMath.abs(ax) * 1e-8);
Assert.assertEquals(ay_DS, ay, FastMath.abs(ay) * 1e-8);
Assert.assertEquals(az_DS, az, FastMath.abs(az) * 1e-8);
}
}
use of org.hipparchus.random.UncorrelatedRandomVectorGenerator in project Orekit by CS-SI.
the class SolarRadiationPressureTest method RealFieldIsotropicTest.
/**
*Testing if the propagation between the FieldPropagation and the propagation
* is equivalent.
* Also testing if propagating X+dX with the propagation is equivalent to
* propagation X with the FieldPropagation and then applying the taylor
* expansion of dX to the result.
*/
@Test
public void RealFieldIsotropicTest() throws OrekitException {
DSFactory factory = new DSFactory(6, 5);
DerivativeStructure a_0 = factory.variable(0, 7e7);
DerivativeStructure e_0 = factory.variable(1, 0.4);
DerivativeStructure i_0 = factory.variable(2, 85 * FastMath.PI / 180);
DerivativeStructure R_0 = factory.variable(3, 0.7);
DerivativeStructure O_0 = factory.variable(4, 0.5);
DerivativeStructure n_0 = factory.variable(5, 0.1);
Field<DerivativeStructure> field = a_0.getField();
DerivativeStructure zero = field.getZero();
FieldAbsoluteDate<DerivativeStructure> J2000 = FieldAbsoluteDate.getJ2000Epoch(field);
Frame EME = FramesFactory.getEME2000();
FieldKeplerianOrbit<DerivativeStructure> FKO = new FieldKeplerianOrbit<>(a_0, e_0, i_0, R_0, O_0, n_0, PositionAngle.MEAN, EME, J2000, Constants.EIGEN5C_EARTH_MU);
FieldSpacecraftState<DerivativeStructure> initialState = new FieldSpacecraftState<>(FKO);
SpacecraftState iSR = initialState.toSpacecraftState();
final OrbitType type = OrbitType.KEPLERIAN;
double[][] tolerance = NumericalPropagator.tolerances(10.0, FKO.toOrbit(), type);
AdaptiveStepsizeFieldIntegrator<DerivativeStructure> integrator = new DormandPrince853FieldIntegrator<>(field, 0.001, 200, tolerance[0], tolerance[1]);
integrator.setInitialStepSize(zero.add(60));
AdaptiveStepsizeIntegrator RIntegrator = new DormandPrince853Integrator(0.001, 200, tolerance[0], tolerance[1]);
RIntegrator.setInitialStepSize(60);
FieldNumericalPropagator<DerivativeStructure> FNP = new FieldNumericalPropagator<>(field, integrator);
FNP.setOrbitType(type);
FNP.setInitialState(initialState);
NumericalPropagator NP = new NumericalPropagator(RIntegrator);
NP.setOrbitType(type);
NP.setInitialState(iSR);
PVCoordinatesProvider sun = CelestialBodyFactory.getSun();
// creation of the force model
OneAxisEllipsoid earth = new OneAxisEllipsoid(6378136.46, 1.0 / 298.25765, FramesFactory.getITRF(IERSConventions.IERS_2010, true));
SolarRadiationPressure forceModel = new SolarRadiationPressure(sun, earth.getEquatorialRadius(), new IsotropicRadiationCNES95Convention(500.0, 0.7, 0.7));
FNP.addForceModel(forceModel);
NP.addForceModel(forceModel);
FieldAbsoluteDate<DerivativeStructure> target = J2000.shiftedBy(1000.);
FieldSpacecraftState<DerivativeStructure> finalState_DS = FNP.propagate(target);
SpacecraftState finalState_R = NP.propagate(target.toAbsoluteDate());
FieldPVCoordinates<DerivativeStructure> finPVC_DS = finalState_DS.getPVCoordinates();
PVCoordinates finPVC_R = finalState_R.getPVCoordinates();
Assert.assertEquals(0, Vector3D.distance(finPVC_DS.toPVCoordinates().getPosition(), finPVC_R.getPosition()), 4.0e-9);
long number = 23091991;
RandomGenerator RG = new Well19937a(number);
GaussianRandomGenerator NGG = new GaussianRandomGenerator(RG);
UncorrelatedRandomVectorGenerator URVG = new UncorrelatedRandomVectorGenerator(new double[] { 0.0, 0.0, 0.0, 0.0, 0.0, 0.0 }, new double[] { 1e3, 0.01, 0.01, 0.01, 0.01, 0.01 }, NGG);
double a_R = a_0.getReal();
double e_R = e_0.getReal();
double i_R = i_0.getReal();
double R_R = R_0.getReal();
double O_R = O_0.getReal();
double n_R = n_0.getReal();
for (int ii = 0; ii < 1; ii++) {
double[] rand_next = URVG.nextVector();
double a_shift = a_R + rand_next[0];
double e_shift = e_R + rand_next[1];
double i_shift = i_R + rand_next[2];
double R_shift = R_R + rand_next[3];
double O_shift = O_R + rand_next[4];
double n_shift = n_R + rand_next[5];
KeplerianOrbit shiftedOrb = new KeplerianOrbit(a_shift, e_shift, i_shift, R_shift, O_shift, n_shift, PositionAngle.MEAN, EME, J2000.toAbsoluteDate(), Constants.EIGEN5C_EARTH_MU);
SpacecraftState shift_iSR = new SpacecraftState(shiftedOrb);
NumericalPropagator shift_NP = new NumericalPropagator(RIntegrator);
shift_NP.setOrbitType(type);
shift_NP.setInitialState(shift_iSR);
shift_NP.addForceModel(forceModel);
SpacecraftState finalState_shift = shift_NP.propagate(target.toAbsoluteDate());
PVCoordinates finPVC_shift = finalState_shift.getPVCoordinates();
// position check
FieldVector3D<DerivativeStructure> pos_DS = finPVC_DS.getPosition();
double x_DS = pos_DS.getX().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double y_DS = pos_DS.getY().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double z_DS = pos_DS.getZ().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
// System.out.println(pos_DS.getX().getPartialDerivative(1));
double x = finPVC_shift.getPosition().getX();
double y = finPVC_shift.getPosition().getY();
double z = finPVC_shift.getPosition().getZ();
Assert.assertEquals(x_DS, x, FastMath.abs(x - pos_DS.getX().getReal()) * 4e-9);
Assert.assertEquals(y_DS, y, FastMath.abs(y - pos_DS.getY().getReal()) * 5e-9);
Assert.assertEquals(z_DS, z, FastMath.abs(z - pos_DS.getZ().getReal()) * 6e-10);
// velocity check
FieldVector3D<DerivativeStructure> vel_DS = finPVC_DS.getVelocity();
double vx_DS = vel_DS.getX().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double vy_DS = vel_DS.getY().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double vz_DS = vel_DS.getZ().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double vx = finPVC_shift.getVelocity().getX();
double vy = finPVC_shift.getVelocity().getY();
double vz = finPVC_shift.getVelocity().getZ();
Assert.assertEquals(vx_DS, vx, FastMath.abs(vx) * 5e-11);
Assert.assertEquals(vy_DS, vy, FastMath.abs(vy) * 3e-10);
Assert.assertEquals(vz_DS, vz, FastMath.abs(vz) * 5e-11);
// acceleration check
FieldVector3D<DerivativeStructure> acc_DS = finPVC_DS.getAcceleration();
double ax_DS = acc_DS.getX().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double ay_DS = acc_DS.getY().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double az_DS = acc_DS.getZ().taylor(rand_next[0], rand_next[1], rand_next[2], rand_next[3], rand_next[4], rand_next[5]);
double ax = finPVC_shift.getAcceleration().getX();
double ay = finPVC_shift.getAcceleration().getY();
double az = finPVC_shift.getAcceleration().getZ();
Assert.assertEquals(ax_DS, ax, FastMath.abs(ax) * 2e-10);
Assert.assertEquals(ay_DS, ay, FastMath.abs(ay) * 4e-10);
Assert.assertEquals(az_DS, az, FastMath.abs(az) * 7e-10);
}
}
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