Examples with CelestialBody org.orekit.bodies.CelestialBody used on opensource projects

Example 46 with CelestialBody

use of org.orekit.bodies.CelestialBody in project Orekit by CS-SI.

the class ODMMetaData method getFrame.

/**
 * Get the reference frame in which data are given: used for state vector and
 * Keplerian elements data (and for the covariance reference frame if none is given).
 *
 * @return the reference frame
 * @throws OrekitException if the reference frame cannot be created.
 */
public Frame getFrame() throws OrekitException {
    final Frame frame = this.getRefFrame();
    final CelestialBody body = this.getCenterBody();
    if (body == null) {
        throw new OrekitException(OrekitMessages.NO_DATA_LOADED_FOR_CELESTIAL_BODY, this.getCenterName());
    }
    // Just return frame if we don't need to shift the center based on CENTER_NAME
    // MCI and ICRF are the only non-earth centered frames specified in Annex A.
    final String frameString = this.getFrameString();
    final boolean isMci = "MCI".equals(frameString);
    final boolean isIcrf = "ICRF".equals(frameString);
    final boolean isSolarSystemBarycenter = CelestialBodyFactory.SOLAR_SYSTEM_BARYCENTER.equals(body.getName());
    if ((!(isMci || isIcrf) && CelestialBodyFactory.EARTH.equals(body.getName())) || (isMci && CelestialBodyFactory.MARS.equals(body.getName())) || (isIcrf && isSolarSystemBarycenter)) {
        return frame;
    }
    // else, translate frame to specified center.
    return new CcsdsModifiedFrame(frame, frameString, body, this.getCenterName());
}

Example 47 with CelestialBody

use of org.orekit.bodies.CelestialBody in project Orekit by CS-SI.

the class L1TransformProviderTest method testSunEarth.

@Test
public void testSunEarth() throws OrekitException {
    // Load Bodies
    final CelestialBody sun = CelestialBodyFactory.getSun();
    final CelestialBody earth = CelestialBodyFactory.getEarth();
    // Set frames
    final Frame sunFrame = sun.getInertiallyOrientedFrame();
    final Frame l1Frame = new L1Frame(sun, earth);
    // Time settings
    final AbsoluteDate date = new AbsoluteDate(2000, 01, 01, 0, 0, 00.000, TimeScalesFactory.getUTC());
    // Compute Earth position in Sun centered frame
    PVCoordinates pvEarth = earth.getPVCoordinates(date, sunFrame);
    Vector3D posEarth = pvEarth.getPosition();
    // Compute L1 position in Sun centered frame
    // (it is important to use transformPosition(Vector3D.ZERO) and *not* getTranslation()
    // because the test should avoid doing wrong interpretation of the meaning and
    // particularly on the sign of the translation)
    Vector3D posL1 = l1Frame.getTransformTo(sunFrame, date).transformPosition(Vector3D.ZERO);
    // check L1 and Earth are aligned as seen from Sun
    Assert.assertEquals(0.0, Vector3D.angle(posEarth, posL1), 1.0e-10);
    // check if Earth is at least 1 000 000km farther than L1
    Assert.assertTrue(posEarth.getNorm() > posL1.getNorm() + 1.0e9);
}

Example 48 with CelestialBody

use of org.orekit.bodies.CelestialBody in project Orekit by CS-SI.

the class L1TransformProviderTest method testL1Orientation.

@Test
public void testL1Orientation() throws OrekitException {
    final AbsoluteDate date0 = new AbsoluteDate(2000, 01, 1, 11, 58, 20.000, TimeScalesFactory.getUTC());
    final CelestialBody sun = CelestialBodyFactory.getSun();
    final CelestialBody earth = CelestialBodyFactory.getEarth();
    final Frame l1Frame = new L1Frame(sun, earth);
    for (double dt = -Constants.JULIAN_DAY; dt <= Constants.JULIAN_DAY; dt += 3600.0) {
        final AbsoluteDate date = date0.shiftedBy(dt);
        final Vector3D sunPositionInL1 = sun.getPVCoordinates(date, l1Frame).getPosition();
        final Vector3D earthPositionInL1 = earth.getPVCoordinates(date, l1Frame).getPosition();
        Assert.assertEquals(0.0, Vector3D.angle(sunPositionInL1, Vector3D.MINUS_I), 3.0e-14);
        Assert.assertEquals(FastMath.PI, Vector3D.angle(earthPositionInL1, Vector3D.MINUS_I), 3.0e-14);
    }
}

Example 49 with CelestialBody

use of org.orekit.bodies.CelestialBody in project Orekit by CS-SI.

the class EclipticProviderTest method checkAlignment.

/**
 * Check alignment of ecliptic +z with Earth-Moon barycenter angular momentum. Angular
 * difference will be checked every month.
 *
 * @param start start date of check.
 * @param end   en date of check.
 * @throws OrekitException on error
 */
private void checkAlignment(AbsoluteDate start, AbsoluteDate end) throws OrekitException {
    // setup
    CelestialBody sun = CelestialBodyFactory.getSun();
    CelestialBody emb = CelestialBodyFactory.getEarthMoonBarycenter();
    Frame heliocentric = sun.getInertiallyOrientedFrame();
    // subject under test
    Frame ecliptic = FramesFactory.getEcliptic(IERSConventions.IERS_2010);
    // verify
    // precise definition is +z is parallel to Earth-Moon barycenter's angular momentum
    // over date range of ephemeris, a season at a time
    double preciseTol = 0.50 * Constants.ARC_SECONDS_TO_RADIANS;
    for (AbsoluteDate date = start; date.compareTo(end) < 0; date = date.shiftedBy(Constants.JULIAN_YEAR / 12.0)) {
        Transform heliocentricToEcliptic = heliocentric.getTransformTo(ecliptic, date);
        Vector3D momentum = emb.getPVCoordinates(date, heliocentric).getMomentum();
        Vector3D actual = heliocentricToEcliptic.transformVector(momentum);
        double angle = Vector3D.angle(Vector3D.PLUS_K, actual);
        Assert.assertEquals("Agrees with ephemerides to within " + preciseTol, 0, angle, preciseTol);
    }
}

Example 50 with CelestialBody

use of org.orekit.bodies.CelestialBody in project Orekit by CS-SI.

the class L2TransformProviderTest method testSunEarth.

@Test
public void testSunEarth() throws OrekitException {
    // Load Bodies
    final CelestialBody sun = CelestialBodyFactory.getSun();
    final CelestialBody earth = CelestialBodyFactory.getEarth();
    // Set frames
    final Frame sunFrame = sun.getInertiallyOrientedFrame();
    final Frame l2Frame = new L2Frame(sun, earth);
    // Time settings
    final AbsoluteDate date = new AbsoluteDate(2000, 01, 01, 0, 0, 00.000, TimeScalesFactory.getUTC());
    // Compute Earth position in Sun centered frame
    PVCoordinates pvEarth = earth.getPVCoordinates(date, sunFrame);
    Vector3D posEarth = pvEarth.getPosition();
    // Compute L2 position in Sun centered frame
    // (it is important to use transformPosition(Vector3D.ZERO) and *not* getTranslation()
    // because the test should avoid doing wrong interpretation of the meaning and
    // particularly on the sign of the translation)
    Vector3D posL2 = l2Frame.getTransformTo(sunFrame, date).transformPosition(Vector3D.ZERO);
    // check L2 and Earth are aligned as seen from Sun
    Assert.assertEquals(0.0, Vector3D.angle(posEarth, posL2), 1.0e-10);
    // check L2 if at least 1 000 000km farther than Earth
    Assert.assertTrue(posL2.getNorm() > posEarth.getNorm() + 1.0e9);
}