Euler.java
/* Copyright 2002-2021 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.ndm.adm.apm;
import java.util.Arrays;
import org.hipparchus.geometry.euclidean.threed.RotationOrder;
import org.orekit.errors.OrekitException;
import org.orekit.errors.OrekitMessages;
import org.orekit.files.ccsds.ndm.adm.AttitudeEndoints;
import org.orekit.files.ccsds.section.CommentsContainer;
/**
* Container for {@link Euler Euler rotations} entries.
* @author Bryan Cazabonne
* @since 10.2
*/
public class Euler extends CommentsContainer {
/** Endpoints (i.e. frames A, B and their relationship). */
private final AttitudeEndoints endpoints;
/** Rotation order of the Euler angles. */
private RotationOrder eulerRotSeq;
/** The frame in which rates are specified. */
private Boolean rateFrameIsA;
/** Euler angles [rad]. */
private double[] rotationAngles;
/** Rotation rate [rad/s]. */
private double[] rotationRates;
/** Indicator for rotation angles. */
private boolean inRotationAngles;
/** Simple constructor.
*/
public Euler() {
this.endpoints = new AttitudeEndoints();
this.rotationAngles = new double[3];
this.rotationRates = new double[3];
this.inRotationAngles = false;
Arrays.fill(rotationAngles, Double.NaN);
Arrays.fill(rotationRates, Double.NaN);
}
/** {@inheritDoc} */
@Override
public void validate(final double version) {
super.validate(version);
endpoints.checkMandatoryEntriesExceptExternalFrame(EulerKey.EULER_FRAME_A,
EulerKey.EULER_FRAME_B,
EulerKey.EULER_DIR);
endpoints.checkExternalFrame(EulerKey.EULER_FRAME_A, EulerKey.EULER_FRAME_B);
checkNotNull(eulerRotSeq, EulerKey.EULER_ROT_SEQ);
final boolean missingAngle = Double.isNaN(rotationAngles[0] + rotationAngles[1] + rotationAngles[2]);
if (missingAngle) {
// if at least one is NaN, all must be NaN (i.e. not initialized)
for (final double ra : rotationAngles) {
if (!Double.isNaN(ra)) {
throw new OrekitException(OrekitMessages.UNINITIALIZED_VALUE_FOR_KEY, "{X|Y|Z}_ANGLE");
}
}
}
final boolean missingRate = Double.isNaN(rotationRates[0] + rotationRates[1] + rotationRates[2]);
if (missingRate) {
// if at least one is NaN, all must be NaN (i.e. not initialized)
for (final double rr : rotationRates) {
if (!Double.isNaN(rr)) {
throw new OrekitException(OrekitMessages.UNINITIALIZED_VALUE_FOR_KEY, "{X|Y|Z}_RATE");
}
}
}
// either angles or rates must be specified
// (angles may be missing in the quaternion/Euler rate case)
if (missingAngle && missingRate) {
throw new OrekitException(OrekitMessages.UNINITIALIZED_VALUE_FOR_KEY, "{X|Y|Z}_{ANGLE|RATE}");
}
}
/** Get the endpoints (i.e. frames A, B and their relationship).
* @return endpoints
*/
public AttitudeEndoints getEndpoints() {
return endpoints;
}
/**
* Get the rotation order of Euler angles.
* @return rotation order
*/
public RotationOrder getEulerRotSeq() {
return eulerRotSeq;
}
/**
* Set the rotation order for Euler angles.
* @param eulerRotSeq order to be set
*/
public void setEulerRotSeq(final RotationOrder eulerRotSeq) {
refuseFurtherComments();
this.eulerRotSeq = eulerRotSeq;
}
/** Check if rates are specified in {@link AttitudeEndoints#getFrameA() frame A}.
* @return true if rates are specified in {@link AttitudeEndoints#getFrameA() frame A}
*/
public boolean rateFrameIsA() {
return rateFrameIsA == null ? false : rateFrameIsA;
}
/** Set the frame in which rates are specified.
* @param rateFrameIsA if true, rates are specified in {@link AttitudeEndoints#getFrameA() frame A}
*/
public void setRateFrameIsA(final boolean rateFrameIsA) {
refuseFurtherComments();
this.rateFrameIsA = rateFrameIsA;
}
/** Check if rates are specified in spacecraft body frame.
* <p>
* {@link #validate(double) Mandatory entries} must have been
* initialized properly to non-null values before this method is called,
* otherwise {@code NullPointerException} will be thrown.
* </p>
* @return true if rates are specified in spacecraft body frame
*/
public boolean isSpacecraftBodyRate() {
return rateFrameIsA ^ endpoints.getFrameA().asSpacecraftBodyFrame() == null;
}
/**
* Get the coordinates of the Euler angles (rad).
* @return rotation angles
*/
public double[] getRotationAngles() {
return rotationAngles.clone();
}
/**
* Set the Euler angle about (rad).
* @param axis rotation axis
* @param angle angle to set
*/
public void setRotationAngle(final char axis, final double angle) {
refuseFurtherComments();
setAngleOrRate(rotationAngles, axis, angle);
}
/**
* Get the rates of the Euler angles (rad/s).
* @return rotation rates
*/
public double[] getRotationRates() {
return rotationRates.clone();
}
/**
* Set the rate of Euler angle (rad/s).
* @param axis rotation axis
* @param rate angle rate to set
*/
public void setRotationRate(final char axis, final double rate) {
refuseFurtherComments();
setAngleOrRate(rotationRates, axis, rate);
}
/** Check if we are in the rotationAngles part of XML files.
* @return true if we are in the rotationAngles part of XML files
*/
boolean inRotationAngles() {
return inRotationAngles;
}
/** Set flag for rotation angle parsing.
* @param inRotationAngles if true, we are in the rotationAngles part of XML files
*/
public void setInRotationAngles(final boolean inRotationAngles) {
refuseFurtherComments();
this.inRotationAngles = inRotationAngles;
}
/** Check if the logical block includes rates.
* @return true if logical block includes rates
*/
public boolean hasRates() {
return !Double.isNaN(rotationRates[0] + rotationRates[1] + rotationRates[2]);
}
/** Set an angle or rate in an array.
* @param array angle or rate array
* @param axis axis name
* @param value angle or rate to set
*/
private void setAngleOrRate(final double[] array, final char axis, final double value) {
refuseFurtherComments();
if (eulerRotSeq != null) {
if (eulerRotSeq.name().charAt(0) == axis && Double.isNaN(array[0])) {
array[0] = value;
} else if (eulerRotSeq.name().charAt(1) == axis && Double.isNaN(array[1])) {
array[1] = value;
} else if (eulerRotSeq.name().charAt(2) == axis && Double.isNaN(array[2])) {
array[2] = value;
}
}
}
}