DSSTCentralBody.java
/* Copyright 2002-2016 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
* limitations under the License.
*/
package org.orekit.propagation.semianalytical.dsst.forces;
import java.util.List;
import org.orekit.attitudes.AttitudeProvider;
import org.orekit.errors.OrekitException;
import org.orekit.forces.gravity.potential.UnnormalizedSphericalHarmonicsProvider;
import org.orekit.frames.Frame;
import org.orekit.propagation.SpacecraftState;
import org.orekit.propagation.events.EventDetector;
import org.orekit.propagation.semianalytical.dsst.utilities.AuxiliaryElements;
/** Central body gravitational contribution to the
* {@link org.orekit.propagation.semianalytical.dsst.DSSTPropagator DSSTPropagator}.
* <p>
* Central body gravitational contribution is made of:
* <ol>
* <li>zonal harmonics contribution</li>
* <li>tesseral harmonics contribution</li>
* </ol>
* </p>
*
* @author Pascal Parraud
*/
public class DSSTCentralBody implements DSSTForceModel {
/** Zonal harmonics contribution. */
private final ZonalContribution zonal;
/** Tesseral harmonics contribution. */
private final TesseralContribution tesseral;
/** DSST Central body constructor.
* <p>
* This constructor limits the zonal short periods to degree 12,
* the tesseral short periods to degree and order 8,
* and the tesseral m-dailies to degree and order 12.
* </p>
* @param centralBodyFrame rotating body frame
* @param centralBodyRotationRate central body rotation rate (rad/s)
* @param provider provider for spherical harmonics
* @param mDailiesOnly if true only M-dailies tesseral harmonics are taken into account for short periodics
* @deprecated since 7.1, replaced with {@link #DSSTCentralBody(Frame, double,
* UnnormalizedSphericalHarmonicsProvider, int, int, int, int, int)}
*/
@Deprecated
public DSSTCentralBody(final Frame centralBodyFrame,
final double centralBodyRotationRate,
final UnnormalizedSphericalHarmonicsProvider provider,
final boolean mDailiesOnly) {
this(centralBodyFrame, centralBodyRotationRate, provider,
12, mDailiesOnly ? -1 : 8, mDailiesOnly ? -1 : 8, 12, 12);
}
/** DSST Central body constructor.
* <p>
* All harmonics are considered for the short-periodic tesseral contribution
* </p>
* @param centralBodyFrame rotating body frame
* @param centralBodyRotationRate central body rotation rate (rad/s)
* @param provider provider for spherical harmonics
* @deprecated since 7.1, replaced with {@link #DSSTCentralBody(Frame, double,
* UnnormalizedSphericalHarmonicsProvider, int, int, int, int, int)}
*/
@Deprecated
public DSSTCentralBody(final Frame centralBodyFrame,
final double centralBodyRotationRate,
final UnnormalizedSphericalHarmonicsProvider provider) {
this(centralBodyFrame, centralBodyRotationRate, provider, false);
}
/** DSST Central body constructor.
* @param centralBodyFrame rotating body frame
* @param centralBodyRotationRate central body rotation rate (rad/s)
* @param provider provider for spherical harmonics
* @param maxDegreeZonalSP maximal degree to consider for short periodics zonal harmonics potential
* (the real degree used may be smaller if the provider does not provide enough terms)
* @param maxDegreeTesseralSP maximal degree to consider for short periodics tesseral harmonics potential
* (the real degree used may be smaller if the provider does not provide enough terms)
* @param maxOrderTesseralSP maximal order to consider for short periodics tesseral harmonics potential
* (the real order used may be smaller if the provider does not provide enough terms)
* @param maxDegreeMdailyTesseralSP maximal degree to consider for short periodics m-daily tesseral harmonics potential
* (the real degree used may be smaller if the provider does not provide enough terms)
* @param maxOrderMdailyTesseralSP maximal order to consider for short periodics m-daily tesseral harmonics potential
* (the real order used may be smaller if the provider does not provide enough terms)
* @since 7.1
*/
public DSSTCentralBody(final Frame centralBodyFrame,
final double centralBodyRotationRate,
final UnnormalizedSphericalHarmonicsProvider provider,
final int maxDegreeZonalSP,
final int maxDegreeTesseralSP, final int maxOrderTesseralSP,
final int maxDegreeMdailyTesseralSP, final int maxOrderMdailyTesseralSP) {
// Zonal harmonics contribution
this.zonal = new ZonalContribution(provider, maxDegreeZonalSP);
// Tesseral harmonics contribution (only if order > 0)
this.tesseral = (provider.getMaxOrder() == 0) ?
null : new TesseralContribution(centralBodyFrame,
centralBodyRotationRate,
provider,
maxDegreeTesseralSP, maxOrderTesseralSP,
maxDegreeMdailyTesseralSP,
maxOrderMdailyTesseralSP);
}
/** {@inheritDoc} */
public List<ShortPeriodTerms> initialize(final AuxiliaryElements aux, final boolean meanOnly)
throws OrekitException {
// Initialize zonal contribution
final List<ShortPeriodTerms> list = zonal.initialize(aux, meanOnly);
// Initialize tesseral contribution if needed
if (tesseral != null) {
list.addAll(tesseral.initialize(aux, meanOnly));
}
return list;
}
/** {@inheritDoc} */
public void initializeStep(final AuxiliaryElements aux)
throws OrekitException {
// Initialize zonal contribution
zonal.initializeStep(aux);
// Initialize tesseral contribution if needed
if (tesseral != null) {
tesseral.initializeStep(aux);
}
}
/** {@inheritDoc} */
public double[] getMeanElementRate(final SpacecraftState spacecraftState)
throws OrekitException {
// Get zonal harmonics contribution to mean elements
final double[] meanElementRate = zonal.getMeanElementRate(spacecraftState);
// Get tesseral resonant harmonics contribution to mean elements
if (tesseral != null) {
final double[] tesseralMeanRate = tesseral.getMeanElementRate(spacecraftState);
for (int i = 0; i < 6; i++) {
meanElementRate[i] += tesseralMeanRate[i];
}
}
return meanElementRate;
}
/** {@inheritDoc} */
public EventDetector[] getEventsDetectors() {
return null;
}
/** {@inheritDoc} */
public void updateShortPeriodTerms(final SpacecraftState ... state)
throws OrekitException {
//relay the call to the Zonal and Tesseral contributions
zonal.updateShortPeriodTerms(state);
if (tesseral != null) {
tesseral.updateShortPeriodTerms(state);
}
}
/** Get the spherical harmonics provider.
* @return the spherical harmonics provider
*/
public UnnormalizedSphericalHarmonicsProvider getProvider() {
return zonal.getProvider();
}
/** {@inheritDoc} */
@Override
public void registerAttitudeProvider(final AttitudeProvider provider) {
//nothing is done since this contribution is not sensitive to attitude
}
}