OMMFile.java
/* Copyright 2002-2020 CS GROUP
* Licensed to CS GROUP (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.files.ccsds;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.hipparchus.util.FastMath;
import org.orekit.orbits.CartesianOrbit;
import org.orekit.orbits.KeplerianOrbit;
import org.orekit.orbits.PositionAngle;
import org.orekit.propagation.SpacecraftState;
import org.orekit.propagation.analytical.tle.TLE;
/**
* This class gathers the informations present in the Orbital Mean-Elements Message (OMM),
* and contains methods to generate a {@link CartesianOrbit}, a {@link KeplerianOrbit},
* a {@link SpacecraftState} and, eventually, a {@link TLE}.
* @author sports
* @since 6.1
*/
public class OMMFile extends OGMFile {
/** Meta-data. */
private final OMMMetaData metaData;
/** Mean motion (the Keplerian Mean motion in revolutions per day). To be used instead of semi-major
* axis if MEAN_ELEMENT_THEORY = SGP/SGP4. */
private double meanMotion;
/** Ephemeris Type, only required if MEAN_ELEMENT_THEORY = SGP/SGP4. Some sources suggest the coding for
* the EPHEMERIS_TYPE keyword: 1 = SGP, 2 = SGP4, 3 = SDP4, 4 = SGP8, 5 = SDP8. Default value = 0.
*/
private int ephemerisType;
/** Classification Type, only required if MEAN_ELEMENT_THEORY = SGP/SGP4. Some sources suggest the
* following coding for the CLASSIFICATION_TYPE keyword: U = unclassified, S = secret. Default value = U.
*/
private char classificationType;
/** NORAD Catalog Number ("Satellite Number"), an integer of up to nine digits. */
private Integer noradID;
/** Element set number for this satellite, only required if MEAN_ELEMENT_THEORY = SGP/SGP4.
* Normally incremented sequentially, but may be out of sync if it is generated from a backup source.
* Used to distinguish different TLEs, and therefore only meaningful if TLE based data is being exchanged. */
private String elementSetNo;
/** Revolution Number, only required if MEAN_ELEMENT_THEORY = SGP/SGP4. */
private int revAtEpoch;
/** SGP/SGP4 drag-like coefficient (in units 1/[Earth radii]), only required if MEAN_ELEMENT_THEORY = SGP/SGP4. */
private Double bStar;
/** First Time Derivative of the Mean Motion, only required if MEAN_ELEMENT_THEORY = SGP. */
private Double meanMotionDot;
/** Second Time Derivative of Mean Motion, only required if MEAN_ELEMENT_THEORY = SGP. */
private Double meanMotionDotDot;
/** TLE related parameters comments. The list contains a string for each line of comment. */
private List<String> dataTleRelatedParametersComment;
/** Create a new OMM file object. */
OMMFile() {
metaData = new OMMMetaData(this);
}
/** Get the meta data.
* @return meta data
*/
@Override
public OMMMetaData getMetaData() {
return metaData;
}
/** Get the orbit mean motion.
* @return the orbit mean motion
*/
public double getMeanMotion() {
return meanMotion;
}
/** Set the orbit mean motion.
* @param motion the mean motion to be set
*/
void setMeanMotion(final double motion) {
this.meanMotion = motion;
}
/** Get the ephemeris type.
* @return the ephemerisType
*/
public int getEphemerisType() {
return ephemerisType;
}
/** Set the ephemeris type.
* @param ephemerisType the ephemeris type to be set
*/
void setEphemerisType(final int ephemerisType) {
this.ephemerisType = ephemerisType;
}
/** Get the classification type.
* @return the classificationType
*/
public char getClassificationType() {
return classificationType;
}
/** Set the classification type.
* @param classificationType the classification type to be set
*/
void setClassificationType(final char classificationType) {
this.classificationType = classificationType;
}
/** Get the NORAD Catalog Number ("Satellite Number").
* @return the NORAD Catalog Number
*/
public Integer getNoradID() {
return noradID;
}
/** Set the NORAD Catalog Number ("Satellite Number").
* @param noradID the element set number to be set
*/
void setNoradID(final Integer noradID) {
this.noradID = noradID;
}
/** Get the element set number for this satellite.
* @return the element set number for this satellite
*/
public String getElementSetNumber() {
return elementSetNo;
}
/** Set the element set number for this satellite.
* @param elementSetNo the element set number to be set
*/
void setElementSetNo(final String elementSetNo) {
this.elementSetNo = elementSetNo;
}
/** Get the revolution rumber.
* @return the revolution rumber
*/
public int getRevAtEpoch() {
return revAtEpoch;
}
/** Set the revolution rumber.
* @param revAtEpoch the Revolution Number to be set
*/
void setRevAtEpoch(final int revAtEpoch) {
this.revAtEpoch = revAtEpoch;
}
/** Get the SGP/SGP4 drag-like coefficient.
* @return the SGP/SGP4 drag-like coefficient
*/
public double getBStar() {
return bStar;
}
/** Set the SGP/SGP4 drag-like coefficient.
* @param bStar the SGP/SGP4 drag-like coefficient to be set
*/
void setbStar(final double bStar) {
this.bStar = bStar;
}
/** Get the first time derivative of the mean motion.
* @return the first time derivative of the mean motion
*/
public double getMeanMotionDot() {
return meanMotionDot;
}
/** Set the first time derivative of the mean motion.
* @param meanMotionDot the first time derivative of the mean motion to be set
*/
void setMeanMotionDot(final double meanMotionDot) {
this.meanMotionDot = meanMotionDot;
}
/** Get the second time derivative of the mean motion.
* @return the second time derivative of the mean motion
*/
public double getMeanMotionDotDot() {
return meanMotionDotDot;
}
/** Set the second time derivative of the mean motion.
* @param meanMotionDotDot the second time derivative of the mean motion to be set
*/
void setMeanMotionDotDot(final double meanMotionDotDot) {
this.meanMotionDotDot = meanMotionDotDot;
}
/** Get the comment for TLE related parameters.
* @return comment for TLE related parameters
*/
public List<String> getTLERelatedParametersComment() {
return Collections.unmodifiableList(dataTleRelatedParametersComment);
}
/** Set the comment for TLE related parameters.
* @param comment comment to set
*/
void setTLERelatedParametersComment(final List<String> comment) {
dataTleRelatedParametersComment = new ArrayList<String>(comment);
}
/** Generate a {@link KeplerianOrbit} based on the OMM mean Keplerian elements.
* If the reference frame is not pseudo-inertial, an exception is raised.
* @return the {@link KeplerianOrbit} generated from the OMM information
*/
public KeplerianOrbit generateKeplerianOrbit() {
setMuUsed();
final double a;
if (Double.isNaN(getA())) {
a = FastMath.cbrt(getMuUsed() / (meanMotion * meanMotion));
} else {
a = getA();
}
return new KeplerianOrbit(a, getE(), getI(), getPa(), getRaan(), getAnomaly(),
PositionAngle.MEAN, metaData.getFrame(), getEpoch(), getMuUsed());
}
/** Generate a {@link CartesianOrbit} from the {@link KeplerianOrbit}.
* @return the {@link CartesianOrbit} generated from the OPM information
*/
public CartesianOrbit generateCartesianOrbit() {
return new CartesianOrbit(generateKeplerianOrbit());
}
/** Generate spacecraft state from the {@link KeplerianOrbit} generated by generateKeplerianOrbit.
* Raises an exception if OMM doesn't contain spacecraft mass information.
* @return the spacecraft state of the OMM
*/
public SpacecraftState generateSpacecraftState() {
return new SpacecraftState(generateKeplerianOrbit(), getMass());
}
/** Generate TLE from OMM file. Launch Year, Launch Day and Launch Piece are not present in the
* OMM file, they have to be set manually by the user with the AdditionalData static class.
* @return the tle
*/
public TLE generateTLE() {
return new TLE(noradID, classificationType,
metaData.getLaunchYear(), metaData.getLaunchNumber(), metaData.getLaunchPiece(),
ephemerisType, Integer.parseInt(elementSetNo), getEpoch(),
meanMotion, meanMotionDot, meanMotionDotDot,
getE(), getI(), getPa(), getRaan(), getAnomaly(), revAtEpoch,
bStar, getDataContext().getTimeScales().getUTC());
}
public static class OMMMetaData extends ODMMetaData {
/** Description of the Mean Element Theory. Indicates the proper method to employ
* to propagate the state. */
private String meanElementTheory;
/** Create a new meta-data.
* @param ommFile OMM file to which these meta-data belongs
*/
OMMMetaData(final OMMFile ommFile) {
super(ommFile);
}
/** Get the description of the Mean Element Theory.
* @return the mean element theory
*/
public String getMeanElementTheory() {
return meanElementTheory;
}
/** Set the description of the Mean Element Theory.
* @param meanElementTheory the mean element theory to be set
*/
void setMeanElementTheory(final String meanElementTheory) {
this.meanElementTheory = meanElementTheory;
}
}
}