1   /* Copyright 2002-2025 CS GROUP
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3    * contributor license agreements.  See the NOTICE file distributed with
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5    * CS licenses this file to You under the Apache License, Version 2.0
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9    *   http://www.apache.org/licenses/LICENSE-2.0
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14   * See the License for the specific language governing permissions and
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17  package org.orekit.attitudes;
18  
19  import org.hipparchus.CalculusFieldElement;
20  import org.hipparchus.Field;
21  import org.hipparchus.analysis.differentiation.UnivariateDerivative1;
22  import org.hipparchus.analysis.differentiation.UnivariateDerivative1Field;
23  import org.hipparchus.geometry.euclidean.threed.FieldRotation;
24  import org.hipparchus.geometry.euclidean.threed.FieldVector3D;
25  import org.hipparchus.geometry.euclidean.threed.Vector3D;
26  import org.hipparchus.util.Binary64Field;
27  import org.hipparchus.util.FastMath;
28  import org.junit.jupiter.api.Assertions;
29  import org.junit.jupiter.api.Test;
30  import org.mockito.Mockito;
31  import org.orekit.frames.FieldTransform;
32  import org.orekit.frames.Frame;
33  import org.orekit.frames.FramesFactory;
34  import org.orekit.time.FieldAbsoluteDate;
35  import org.orekit.utils.FieldAngularCoordinates;
36  
37  
38  class FieldAttitudeTest {
39  
40      @Test
41      void testShift() {
42          doTestShift(Binary64Field.getInstance());
43      }
44  
45      @Test
46      void testSpin() {
47          doTestSpin(Binary64Field.getInstance());
48      }
49  
50      private <T extends CalculusFieldElement<T>> void doTestShift(final Field<T> field){
51          T zero = field.getZero();
52          T one  = field.getOne();
53          T rate = one.multiply(2 * FastMath.PI / (12 * 60));
54          FieldAttitude<T> attitude = new FieldAttitude<>(new FieldAbsoluteDate<>(field), FramesFactory.getEME2000(),
55                          new FieldRotation<>(one, zero, zero, zero, false),
56                                              new FieldVector3D<>(rate, new FieldVector3D<>(zero, zero, one)), new FieldVector3D<>(zero, zero, zero));
57          Assertions.assertEquals(rate.getReal(), attitude.getSpin().getNorm().getReal(), 1.0e-10);
58          double dt_R = 10.0;
59          T dt = zero.add(dt_R);
60  
61          T alpha = rate.multiply(dt);
62          FieldAttitude<T> shifted = attitude.shiftedBy(dt);
63          Assertions.assertEquals(rate.getReal(), shifted.getSpin().getNorm().getReal(), 1.0e-10);
64          Assertions.assertEquals(alpha.getReal(), FieldRotation.distance(attitude.getRotation(), shifted.getRotation()).getReal(), 1.0e-10);
65  
66          FieldVector3D<T> xSat = shifted.getRotation().applyInverseTo(Vector3D.PLUS_I);
67          Assertions.assertEquals(0.0, xSat.subtract(new FieldVector3D<>(alpha.cos(), alpha.sin(), zero)).getNorm().getReal(), 1.0e-10);
68          FieldVector3D<T> ySat = shifted.getRotation().applyInverseTo(Vector3D.PLUS_J);
69          Assertions.assertEquals(0.0, ySat.subtract(new FieldVector3D<>(alpha.sin().multiply(-1), alpha.cos(), zero)).getNorm().getReal(), 1.0e-10);
70          FieldVector3D<T> zSat = shifted.getRotation().applyInverseTo(Vector3D.PLUS_K);
71          Assertions.assertEquals(0.0, zSat.subtract(Vector3D.PLUS_K).getNorm().getReal(), 1.0e-10);
72  
73      }
74  
75  
76      private <T extends CalculusFieldElement<T>> void doTestSpin(final Field<T> field) {
77          T zero = field.getZero();
78          T rate = zero.add(2 * FastMath.PI / (12 * 60));
79          FieldAttitude<T> attitude = new FieldAttitude<>(new FieldAbsoluteDate<>(field), FramesFactory.getEME2000(),
80                                                          new FieldRotation<>(zero.add(0.48), zero.add(0.64), zero.add(0.36), zero.add(0.48), false),
81                                                          new FieldVector3D<>(rate, FieldVector3D.getPlusK(field)), FieldVector3D.getZero(field));
82          Assertions.assertEquals(rate.getReal(), attitude.getSpin().getNorm().getReal(), 1.0e-10);
83          T dt = zero.add(10.0);
84          FieldAttitude<T> shifted = attitude.shiftedBy(dt);
85          Assertions.assertEquals(rate.getReal(), shifted.getSpin().getNorm().getReal(), 1.0e-10);
86  
87          FieldVector3D<T> shiftedX  = shifted.getRotation().applyInverseTo(Vector3D.PLUS_I);
88          FieldVector3D<T> shiftedY  = shifted.getRotation().applyInverseTo(Vector3D.PLUS_J);
89          FieldVector3D<T> shiftedZ  = shifted.getRotation().applyInverseTo(Vector3D.PLUS_K);
90          FieldVector3D<T> originalX = attitude.getRotation().applyInverseTo(Vector3D.PLUS_I);
91          FieldVector3D<T> originalY = attitude.getRotation().applyInverseTo(Vector3D.PLUS_J);
92          FieldVector3D<T> originalZ = attitude.getRotation().applyInverseTo(Vector3D.PLUS_K);
93          Assertions.assertEquals( FastMath.cos(rate.getReal() * dt.getReal()), FieldVector3D.dotProduct(shiftedX, originalX).getReal(), 1.0e-10);
94          Assertions.assertEquals( FastMath.sin(rate.getReal() * dt.getReal()), FieldVector3D.dotProduct(shiftedX, originalY).getReal(), 1.0e-10);
95          Assertions.assertEquals( 0.0,                 FieldVector3D.dotProduct(shiftedX, originalZ).getReal(), 1.0e-10);
96          Assertions.assertEquals(-FastMath.sin(rate.getReal() * dt.getReal()), FieldVector3D.dotProduct(shiftedY, originalX).getReal(), 1.0e-10);
97          Assertions.assertEquals( FastMath.cos(rate.getReal() * dt.getReal()), FieldVector3D.dotProduct(shiftedY, originalY).getReal(), 1.0e-10);
98          Assertions.assertEquals( 0.0,                 FieldVector3D.dotProduct(shiftedY, originalZ).getReal(), 1.0e-10);
99          Assertions.assertEquals( 0.0,                 FieldVector3D.dotProduct(shiftedZ, originalX).getReal(), 1.0e-10);
100         Assertions.assertEquals( 0.0,                 FieldVector3D.dotProduct(shiftedZ, originalY).getReal(), 1.0e-10);
101         Assertions.assertEquals( 1.0,                 FieldVector3D.dotProduct(shiftedZ, originalZ).getReal(), 1.0e-10);
102 
103         FieldVector3D<T> forward = FieldAngularCoordinates.estimateRate(attitude.getRotation(), shifted.getRotation(), dt);
104         Assertions.assertEquals(0.0, forward.subtract(attitude.getSpin()).getNorm().getReal(), 1.0e-10);
105 
106         FieldVector3D<T> reversed = FieldAngularCoordinates.estimateRate(shifted.getRotation(), attitude.getRotation(), dt);
107         Assertions.assertEquals(0.0, reversed.add(attitude.getSpin()).getNorm().getReal(), 1.0e-10);
108 
109     }
110 
111     @Test
112     void testWithReferenceFrame() {
113         // GIVEN
114         final UnivariateDerivative1Field field = UnivariateDerivative1Field.getInstance();
115         final FieldAbsoluteDate<UnivariateDerivative1> date = new FieldAbsoluteDate<>(field).shiftedBy(new UnivariateDerivative1(0, 1));
116         final FieldAngularCoordinates<UnivariateDerivative1> angularCoordinates = new FieldAngularCoordinates<>(FieldRotation.getIdentity(field),
117                 FieldVector3D.getZero(field));
118         final Frame frame = FramesFactory.getEME2000();
119         final FieldAttitude<UnivariateDerivative1> attitude = new FieldAttitude<>(date, frame, angularCoordinates);
120         final Frame mockedFrame = Mockito.mock(Frame.class);
121         Mockito.when(mockedFrame.getTransformTo(frame, date)).thenReturn(new FieldTransform<>(date,
122                 FieldRotation.getIdentity(field), FieldVector3D.getPlusI(field)));
123         // WHEN
124         final FieldAttitude<UnivariateDerivative1> attitudeInNonInertialFrame = attitude.withReferenceFrame(mockedFrame);
125         // THEN
126         Assertions.assertEquals(1., attitudeInNonInertialFrame.getSpin().getX().getReal());
127     }
128 
129 }
130