1   /* Copyright 2002-2022 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.forces.drag;
18  
19  import java.util.List;
20  
21  import org.hipparchus.CalculusFieldElement;
22  import org.hipparchus.geometry.euclidean.threed.FieldRotation;
23  import org.hipparchus.geometry.euclidean.threed.FieldVector3D;
24  import org.hipparchus.geometry.euclidean.threed.Rotation;
25  import org.hipparchus.geometry.euclidean.threed.Vector3D;
26  import org.orekit.frames.Frame;
27  import org.orekit.time.AbsoluteDate;
28  import org.orekit.time.FieldAbsoluteDate;
29  import org.orekit.utils.ParameterDriver;
30  
31  /** Interface for spacecraft that are sensitive to atmospheric drag forces.
32   *
33   * @see DragForce
34   * @author Luc Maisonobe
35   * @author Pascal Parraud
36   */
37  public interface DragSensitive {
38  
39      /** Parameter name for drag coefficient enabling Jacobian processing. */
40      String DRAG_COEFFICIENT = "drag coefficient";
41  
42      /** Parameter name for lift ration enabling Jacobian processing.
43       * <p>
44       * The lift ratio is the proportion of atmosphere modecules that will
45       * experience specular reflection when hitting spacecraft instead
46       * of experiencing diffuse reflection. The ratio is between 0 and 1,
47       * 0 meaning there are no specular reflection, only diffuse reflection,
48       * and hence no lift effect.
49       * </p>
50       * @since 9.0
51       */
52      String LIFT_RATIO = "lift ratio";
53  
54      /** Get the drivers for supported parameters.
55       * @return parameters drivers
56       * @since 8.0
57       */
58      List<ParameterDriver> getDragParametersDrivers();
59  
60      /** Compute the acceleration due to drag.
61       * <p>
62       * The computation includes all spacecraft specific characteristics
63       * like shape, area and coefficients.
64       * </p>
65       * @param date current date
66       * @param frame inertial reference frame for state (both orbit and attitude)
67       * @param position position of spacecraft in reference frame
68       * @param rotation orientation (attitude) of the spacecraft with respect to reference frame
69       * @param mass current mass
70       * @param density atmospheric density at spacecraft position
71       * @param relativeVelocity relative velocity of atmosphere with respect to spacecraft,
72       * in the same inertial frame as spacecraft orbit (m/s)
73       * @param parameters values of the force model parameters
74       * @return spacecraft acceleration in the same inertial frame as spacecraft orbit (m/s²)
75       */
76      Vector3D dragAcceleration(AbsoluteDate date, Frame frame, Vector3D position,
77                                Rotation rotation, double mass,
78                                double density, Vector3D relativeVelocity,
79                                double[] parameters);
80  
81      /** Compute the acceleration due to drag.
82       * <p>
83       * The computation includes all spacecraft specific characteristics
84       * like shape, area and coefficients.
85       * </p>
86       * @param date current date
87       * @param frame inertial reference frame for state (both orbit and attitude)
88       * @param position position of spacecraft in reference frame
89       * @param rotation orientation (attitude) of the spacecraft with respect to reference frame
90       * @param mass current mass
91       * @param density atmospheric density at spacecraft position
92       * @param relativeVelocity relative velocity of atmosphere with respect to spacecraft,
93       * in the same inertial frame as spacecraft orbit (m/s)
94       * @param parameters values of the force model parameters
95       * @param <T> instance of a CalculusFieldElement
96       * @return spacecraft acceleration in the same inertial frame as spacecraft orbit (m/s²)
97       * @since 9.0
98       */
99      <T extends CalculusFieldElement<T>> FieldVector3D<T> dragAcceleration(FieldAbsoluteDate<T> date, Frame frame,
100                                                                       FieldVector3D<T> position,
101                                                                       FieldRotation<T> rotation, T mass,
102                                                                       T density, FieldVector3D<T> relativeVelocity,
103                                                                       T[] parameters);
104 }