/* Copyright 2002-2017 CS Systèmes d'Information
* Licensed to CS Systèmes d'Information (CS) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* CS licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
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package org.orekit.propagation.events;
import org.hipparchus.geometry.euclidean.threed.Vector3D;
import org.hipparchus.util.FastMath;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;
import org.orekit.Utils;
import org.orekit.bodies.OneAxisEllipsoid;
import org.orekit.errors.OrekitException;
import org.orekit.frames.FramesFactory;
import org.orekit.orbits.EquinoctialOrbit;
import org.orekit.orbits.Orbit;
import org.orekit.propagation.Propagator;
import org.orekit.propagation.SpacecraftState;
import org.orekit.propagation.analytical.EcksteinHechlerPropagator;
import org.orekit.propagation.events.EventsLogger.LoggedEvent;
import org.orekit.propagation.events.handlers.ContinueOnEvent;
import org.orekit.time.AbsoluteDate;
import org.orekit.time.TimeScale;
import org.orekit.time.TimeScalesFactory;
import org.orekit.utils.Constants;
import org.orekit.utils.IERSConventions;
import org.orekit.utils.PVCoordinates;
public class LatitudeCrossingDetectorTest {
@Test
public void testRegularCrossing() throws OrekitException {
final OneAxisEllipsoid earth = new OneAxisEllipsoid(Constants.WGS84_EARTH_EQUATORIAL_RADIUS,
Constants.WGS84_EARTH_FLATTENING,
FramesFactory.getITRF(IERSConventions.IERS_2010, true));
LatitudeCrossingDetector d =
new LatitudeCrossingDetector(60.0, 1.e-6, earth, FastMath.toRadians(60.0)).
withHandler(new ContinueOnEvent<LatitudeCrossingDetector>());
Assert.assertEquals(60.0, d.getMaxCheckInterval(), 1.0e-15);
Assert.assertEquals(1.0e-6, d.getThreshold(), 1.0e-15);
Assert.assertEquals(60.0, FastMath.toDegrees(d.getLatitude()), 1.0e-14);
Assert.assertEquals(AbstractDetector.DEFAULT_MAX_ITER, d.getMaxIterationCount());
final TimeScale utc = TimeScalesFactory.getUTC();
final Vector3D position = new Vector3D(-6142438.668, 3492467.56, -25767.257);
final Vector3D velocity = new Vector3D(505.848, 942.781, 7435.922);
final AbsoluteDate date = new AbsoluteDate(2003, 9, 16, utc);
final Orbit orbit = new EquinoctialOrbit(new PVCoordinates(position, velocity),
FramesFactory.getEME2000(), date,
Constants.EIGEN5C_EARTH_MU);
Propagator propagator =
new EcksteinHechlerPropagator(orbit,
Constants.EIGEN5C_EARTH_EQUATORIAL_RADIUS,
Constants.EIGEN5C_EARTH_MU,
Constants.EIGEN5C_EARTH_C20,
Constants.EIGEN5C_EARTH_C30,
Constants.EIGEN5C_EARTH_C40,
Constants.EIGEN5C_EARTH_C50,
Constants.EIGEN5C_EARTH_C60);
EventsLogger logger = new EventsLogger();
propagator.addEventDetector(logger.monitorDetector(d));
propagator.propagate(date.shiftedBy(Constants.JULIAN_DAY));
AbsoluteDate previous = null;
for (LoggedEvent e : logger.getLoggedEvents()) {
SpacecraftState state = e.getState();
double latitude = earth.transform(state.getPVCoordinates(earth.getBodyFrame()).getPosition(),
earth.getBodyFrame(), null).getLatitude();
Assert.assertEquals(60.0, FastMath.toDegrees(latitude), 3.0e-10);
if (previous != null) {
if (e.isIncreasing()) {
// crossing northward
Assert.assertTrue(state.getPVCoordinates().getVelocity().getZ() > 3611.0);
Assert.assertEquals(4954.70, state.getDate().durationFrom(previous), 0.01);
} else {
// crossing southward
Assert.assertTrue(state.getPVCoordinates().getVelocity().getZ() < -3615.0);
Assert.assertEquals(956.17, state.getDate().durationFrom(previous), 0.01);
}
}
previous = state.getDate();
}
Assert.assertEquals(30, logger.getLoggedEvents().size());
}
@Test
public void testNoCrossing() throws OrekitException {
final OneAxisEllipsoid earth = new OneAxisEllipsoid(Constants.WGS84_EARTH_EQUATORIAL_RADIUS,
Constants.WGS84_EARTH_FLATTENING,
FramesFactory.getITRF(IERSConventions.IERS_2010, true));
LatitudeCrossingDetector d =
new LatitudeCrossingDetector(10.0, 1.e-6, earth, FastMath.toRadians(82.0)).
withHandler(new ContinueOnEvent<LatitudeCrossingDetector>());
Assert.assertEquals(10.0, d.getMaxCheckInterval(), 1.0e-15);
Assert.assertEquals(1.0e-6, d.getThreshold(), 1.0e-15);
Assert.assertEquals(82.0, FastMath.toDegrees(d.getLatitude()), 1.0e-14);
Assert.assertEquals(AbstractDetector.DEFAULT_MAX_ITER, d.getMaxIterationCount());
final TimeScale utc = TimeScalesFactory.getUTC();
final Vector3D position = new Vector3D(-6142438.668, 3492467.56, -25767.257);
final Vector3D velocity = new Vector3D(505.848, 942.781, 7435.922);
final AbsoluteDate date = new AbsoluteDate(2003, 9, 16, utc);
final Orbit orbit = new EquinoctialOrbit(new PVCoordinates(position, velocity),
FramesFactory.getEME2000(), date,
Constants.EIGEN5C_EARTH_MU);
Propagator propagator =
new EcksteinHechlerPropagator(orbit,
Constants.EIGEN5C_EARTH_EQUATORIAL_RADIUS,
Constants.EIGEN5C_EARTH_MU,
Constants.EIGEN5C_EARTH_C20,
Constants.EIGEN5C_EARTH_C30,
Constants.EIGEN5C_EARTH_C40,
Constants.EIGEN5C_EARTH_C50,
Constants.EIGEN5C_EARTH_C60);
EventsLogger logger = new EventsLogger();
propagator.addEventDetector(logger.monitorDetector(d));
propagator.propagate(date.shiftedBy(Constants.JULIAN_DAY));
Assert.assertEquals(0, logger.getLoggedEvents().size());
}
@Before
public void setUp() {
Utils.setDataRoot("regular-data");
}
}