1 /* Copyright 2002-2025 CS GROUP
2 * Licensed to CS GROUP (CS) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * CS licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.orekit.files.ccsds.ndm.adm.apm;
18
19 import java.util.Arrays;
20
21 import org.hipparchus.complex.Quaternion;
22 import org.orekit.errors.OrekitException;
23 import org.orekit.errors.OrekitMessages;
24 import org.orekit.files.ccsds.ndm.adm.AttitudeEndpoints;
25 import org.orekit.files.ccsds.section.CommentsContainer;
26
27 /**
28 * Container for Attitude Parameter Message quaternion logical block.
29 * <p>
30 * Beware that the Orekit getters and setters all rely on SI units. The parsers
31 * and writers take care of converting these SI units into CCSDS mandatory units.
32 * The {@link org.orekit.utils.units.Unit Unit} class provides useful
33 * {@link org.orekit.utils.units.Unit#fromSI(double) fromSi} and
34 * {@link org.orekit.utils.units.Unit#toSI(double) toSI} methods in case the callers
35 * already use CCSDS units instead of the API SI units. The general-purpose
36 * {@link org.orekit.utils.units.Unit Unit} class (without an 's') and the
37 * CCSDS-specific {@link org.orekit.files.ccsds.definitions.Units Units} class
38 * (with an 's') also provide some predefined units. These predefined units and the
39 * {@link org.orekit.utils.units.Unit#fromSI(double) fromSi} and
40 * {@link org.orekit.utils.units.Unit#toSI(double) toSI} conversion methods are indeed
41 * what the parsers and writers use for the conversions.
42 * </p>
43 * @author Bryan Cazabonne
44 * @since 10.2
45 */
46 public class ApmQuaternion extends CommentsContainer {
47
48 /** Endpoints (i.e. frames A, B and their relationship). */
49 private final AttitudeEndpoints endpoints;
50
51 /** Quaternion. */
52 private final double[] q;
53
54 /** Quaternion derivative. */
55 private final double[] qDot;
56
57 /** Simple constructor.
58 */
59 public ApmQuaternion() {
60 endpoints = new AttitudeEndpoints();
61 q = new double[4];
62 qDot = new double[4];
63 Arrays.fill(q, Double.NaN);
64 Arrays.fill(qDot, Double.NaN);
65 }
66
67 /** {@inheritDoc} */
68 @Override
69 public void validate(final double version) {
70 super.validate(version);
71 if (version < 2.0) {
72 endpoints.checkMandatoryEntriesExceptExternalFrame(version,
73 ApmQuaternionKey.Q_FRAME_A,
74 ApmQuaternionKey.Q_FRAME_B,
75 ApmQuaternionKey.Q_DIR);
76 endpoints.checkExternalFrame(ApmQuaternionKey.Q_FRAME_A, ApmQuaternionKey.Q_FRAME_B);
77 } else {
78 endpoints.checkMandatoryEntriesExceptExternalFrame(version,
79 ApmQuaternionKey.REF_FRAME_A,
80 ApmQuaternionKey.REF_FRAME_B,
81 ApmQuaternionKey.Q_DIR);
82 endpoints.checkExternalFrame(ApmQuaternionKey.REF_FRAME_A, ApmQuaternionKey.REF_FRAME_B);
83 }
84 if (Double.isNaN(q[0] + q[1] + q[2] + q[3])) {
85 throw new OrekitException(OrekitMessages.UNINITIALIZED_VALUE_FOR_KEY, "Q{C|1|2|3}");
86 }
87 }
88
89 /** Get the endpoints (i.e. frames A, B and their relationship).
90 * @return endpoints
91 */
92 public AttitudeEndpoints getEndpoints() {
93 return endpoints;
94 }
95
96 /**
97 * Get the quaternion.
98 * @return quaternion
99 */
100 public Quaternion getQuaternion() {
101 return new Quaternion(q[0], q[1], q[2], q[3]);
102 }
103
104 /**
105 * Set quaternion component.
106 * @param index component index (0 is scalar part)
107 * @param value quaternion component
108 */
109 public void setQ(final int index, final double value) {
110 refuseFurtherComments();
111 this.q[index] = value;
112 }
113
114 /**
115 * Get the quaternion derivative.
116 * @return quaternion derivative
117 */
118 public Quaternion getQuaternionDot() {
119 return new Quaternion(qDot[0], qDot[1], qDot[2], qDot[3]);
120 }
121
122 /**
123 * Set quaternion derivative component.
124 * @param index component index (0 is scalar part)
125 * @param derivative quaternion derivative component
126 */
127 public void setQDot(final int index, final double derivative) {
128 refuseFurtherComments();
129 this.qDot[index] = derivative;
130 }
131
132 /** Check if the logical block includes rates.
133 * @return true if logical block includes rates
134 */
135 public boolean hasRates() {
136 return !Double.isNaN(qDot[0] + qDot[1] + qDot[2] + qDot[3]);
137 }
138
139 }