A method for navigation and registration of lunar images from geostationary satellites based on precise geometric position calculation

Abstract

The invention discloses a geostationary satellite lunar image navigation registration method based on geometric position precise calculation, belongs to the field of positioning and measurement technology, and is used for lunar observation image navigation registration. Data preparation includes preparing satellite attitude data, lunar ephemeris data, lunar image data, satellite position and speed data; data processing includes edge detection, ellipse fitting, obtaining ellipse parameters, image clipping, Gaussian filtering, Gaussian filtering results are fed back to edge detection, ellipse fitting obtains the geometric center of the lunar image, and the ellipse parameters are used to verify the fitting results; model construction includes establishing a conversion matrix between coordinate systems, calculating the scanning angle and step angle of the image center, obtaining the full-moon scanning angle and step angle, using the method of positioning the lunar surface point using the optical axis of the sensor, converting the two angles of the lunar surface point into lunar surface coordinates, and finally outputting the registration results. The invention can successfully realize the conversion of lunar image coordinates to lunar surface coordinates with high accuracy.

Description

Technical Field

[0001] The invention discloses a geostationary satellite lunar image navigation registration method based on geometric position precise calculation, belonging to the technical field of positioning measurement. Background Art

[0002] The moon has high stability and can be used as a calibration object for satellite sensors. At present, most of them use the lunar irradiance model as a reference for satellite calibration. However, the moon's libration and lunar phase angle affect the accuracy of the lunar irradiance model. Some characteristic areas of the moon have high calibration significance, so it is necessary to obtain lunar images with geographic information to select these characteristic areas as calibration targets. The existing method maps the lunar image to the lunar coordinates by rotating it three times, mainly by calculating the cross-correlation diagram of the template image with known lunar coordinates and the original lunar observation image, and using the cross-correlation diagram to calculate the rotation angle. This method is more dependent on the accuracy of the algorithm. The image matching algorithm is also limited by the lunar phase and has a high uncertainty. The method designed by the present invention only needs to consider the geometric position of the Earth-Moon-Saturn, find the position where the sensor optical axis points to the lunar point, and use the conversion relationship between the coordinate systems to gradually convert the lunar image coordinates into lunar geographic coordinates. Summary of the invention

[0003] The purpose of the present invention is to provide a geostationary satellite lunar image navigation registration method based on geometric position precise calculation to solve the problem in the prior art that it is difficult to determine the correspondence between the geostationary satellite lunar observation image and the coordinates of the lunar surface point.

[0004] Geostationary satellite lunar image navigation registration method based on geometric position precise solution, including data preparation, data processing and model construction;

[0005] Data preparation includes preparing satellite attitude data, lunar ephemeris data, lunar image data, satellite position and velocity data;

[0006] Data processing includes edge detection, ellipse fitting, obtaining ellipse parameters, image cropping, and Gaussian filtering. The Gaussian filtering result is fed back to edge detection, the geometric center of the lunar image is obtained by ellipse fitting, and the ellipse parameters are used to verify the fitting results.

[0007] Model construction includes establishing a transformation matrix between coordinate systems, calculating the scanning angle and step angle of the image center, obtaining the scanning angle and step angle of the entire moon, using the method of locating the lunar point using the sensor optical axis, converting the two angles of the lunar point into lunar coordinates, and finally outputting the alignment results.

[0008] Establishing the transformation matrix between coordinate systems includes establishing the satellite orbit coordinate system To the inertial coordinate system The rotation matrix , Satellite body coordinate system To the satellite orbit coordinate system The rotation matrix , Satellite body coordinate system To the inertial coordinate system The rotation matrix , Inertial coordinate system Fixed coordinate system to the moon The rotation matrix .

[0009] Establishing satellite orbit coordinate system To the inertial coordinate system The rotation matrix include:

[0010] ; ;

[0011] ; ;

[0012] In the formula, and Satellites in The position and velocity vectors are , , are the components of the rotation matrix in three dimensions.

[0013] Establishing the satellite coordinate system To the satellite orbit coordinate system The rotation matrix include:

[0014] ;

[0015] ;

[0016] ;

[0017] ;

[0018] In the formula, , , denote the roll angle, pitch angle and yaw angle respectively, , , Respectively The three coordinate axes rotate counterclockwise , , The result after the angle.

[0019] Establishing the satellite coordinate system To the inertial coordinate system The rotation matrix include:

[0020] .

[0021] Establishing an inertial coordinate system Fixed coordinate system to the moon The rotation matrix include:

[0022] ;

[0023] In the formula, , , are the three lunar libration parameters of the Moon relative to the International Celestial Reference Frame, for of Coordinate axis rotates counterclockwise The result after the angle, for of Coordinate axis rotates counterclockwise The result after the angle, for of Coordinate axis rotates counterclockwise The result after the angle.

[0024] The scanning angle and step angle of the lunar image geometric center are obtained, including the geocentric celestial coordinate system. The position of the moon under the moon, according to the coordinated universal time when the moon image was observed , using the ephemeris Calculate the moon center coordinate vector at the current moment , using the constant matrix The coordinates of the moon center are changed from Go to ;

[0025] Use interpolation algorithm to obtain the observation time Satellite positions below , calculate the moon center with the satellite mass center as the origin Coordinates in the frame , then according to Seek the Moon's Heart Next position:

[0026] ; ;

[0027] Calculate the coordinates of the moon's center of mass under the satellite sensor, by Find the sensor optical axis at Coordinates pointing down to the center of the moon , find the scanning angle where the image center is located and step angle :

[0028] ; .

[0029] The sensor optical axis locates the lunar surface point including the satellite center of mass as the origin Establish a right-handed Cartesian coordinate system, the coordinates of the moon's center of mass are , the sensor optical axis vector starts from the satellite's center of mass and points to a point on the front of the moon , solve Coordinates in right-handed Cartesian coordinate system ;

[0030] There is a Starting line , passing through point , the end point is point , There is at least one intersection with the lunar surface, and the known points Scanning angle and step angle, find the direction vector of the sensor optical axis :

[0031] ; ; ;

[0032] Will By extending the unit vector by multiples, we get Coordinates , line segment Passing point ,point and Point , line segment The parametric equation is:

[0033] ;

[0034] In the formula, is a known multiple, is the parameter to be determined of the parametric equation, yes The coordinate value of .

[0035] The sensor optical axis locates the lunar point including the lunar equation:

[0036] ;

[0037] In the formula, is the radius of the moon, , , are the three position unknowns of the lunar equation;

[0038] Line segment Substitute the parametric equation into the lunar equation:

[0039] ; ;

[0040] ; ; ;

[0041] In the formula, , , are the three coefficients of the equation, and the calculation formula is The value of the line segment The number of nodes with the Moon.

[0042] Converting the two angles of a lunar point into lunar coordinates involves converting the row and column numbers of the lunar image point into two angles:

[0043] ;

[0044] ;

[0045] In the formula, Respectively represent the row and column numbers of the moon image, Represent the two corners of the moon image, Represents the angles in the north-south and east-west directions respectively. Respectively represent the row and column numbers where the center of the lunar image is located, Respectively represent the angular sampling interval of the satellite in the north-south and east-west directions;

[0046] Will The two angles are converted into lunar points. The coordinates of the lunar point are obtained by coordinate transformation. The coordinates of:

[0047] ;

[0048] In the formula, Indicate point Fixed coordinate system on the moon The coordinates below.

[0049] Compared with the prior art, the present invention has the following beneficial effects: based on the geostationary satellite observation mode, the present invention studies the geometric position relationship between satellite sensors and the moon in space, and develops a method for locating the coordinate position of points on the lunar surface from geostationary satellite lunar observation images. Regardless of whether it is a full moon or a waning moon, the conversion of lunar image coordinates to lunar surface coordinates can be successfully realized with high accuracy. The two experimental lunar images have consistent longitude and latitude ranges in feature areas such as large-area impact craters such as Tycho Crater, and the converted images can also match the actual lunar images. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a technical flow chart of the present invention;

[0051] Figure 2 is the moon detection edge map of the crescent moon;

[0052] Figure 3 It is the original image of the crescent moon;

[0053] Figure 4 is the lunar detection edge map for the entire moon;

[0054] Figure 5 It is the original image of the full moon;

[0055] Figure 6 is the fitting result of the waning moon;

[0056] Figure 7 is the fitting result of the whole month;

[0057] Figure 8 It is a relationship diagram of the earth, moon and satellite;

[0058] Fig. 9 It is the relationship diagram between the sensor optical axis vector coordinates and the scanning angle and step angle;

[0059] Fig.10 It is a graph of the relationship between the optical axis vector, the lunar surface point and the coordinates of the lunar image in the lunar coordinate system;

[0060] Fig.11 It is a relationship diagram for solving unit vectors;

[0061] Fig.12 It is the calculation result of the waning moon;

[0062] Fig.13 It is the calculation result for the whole month. DETAILED DESCRIPTION

[0063] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0064] Geostationary satellite lunar image navigation registration method based on geometric position precise solution, including data preparation, data processing and model construction;

[0065] Data preparation includes preparing satellite attitude data, lunar ephemeris data, lunar image data, satellite position and velocity data;

[0066] Data processing includes edge detection, ellipse fitting, obtaining ellipse parameters, image cropping, and Gaussian filtering. The Gaussian filtering result is fed back to edge detection, the geometric center of the lunar image is obtained by ellipse fitting, and the ellipse parameters are used to verify the fitting results.

[0067] Model construction includes establishing a transformation matrix between coordinate systems, calculating the scanning angle and step angle of the image center, obtaining the scanning angle and step angle of the entire moon, using the method of locating the lunar point using the sensor optical axis, converting the two angles of the lunar point into lunar coordinates, and finally outputting the alignment results.

[0068] Establishing the transformation matrix between coordinate systems includes establishing the satellite orbit coordinate system To the inertial coordinate system The rotation matrix , Satellite body coordinate system To the satellite orbit coordinate system The rotation matrix , Satellite body coordinate system To the inertial coordinate system The rotation matrix , Inertial coordinate system Fixed coordinate system to the moon The rotation matrix .

[0069] Establishing satellite orbit coordinate system To the inertial coordinate system The rotation matrix include:

[0070] ; ;

[0071] ; ;

[0072] In the formula, and Satellites in The position and velocity vectors are , , are the components of the rotation matrix in three dimensions.

[0073] Establishing the satellite coordinate system To the satellite orbit coordinate system The rotation matrix include:

[0074] ;

[0075] ;

[0076] ;

[0077] ;

[0078] In the formula, , , denote the roll angle, pitch angle and yaw angle respectively, , , Respectively The three coordinate axes rotate counterclockwise , , The result after the angle.

[0079] Establishing the satellite coordinate system To the inertial coordinate system The rotation matrix include:

[0080] .

[0081] Establishing an inertial coordinate system Fixed coordinate system to the moon The rotation matrix include:

[0082] ;

[0083] In the formula, , , are the three lunar libration parameters of the Moon relative to the International Celestial Reference Frame, for of Coordinate axis rotates counterclockwise The result after the angle, for of Coordinate axis rotates counterclockwise The result after the angle, for of Coordinate axis rotates counterclockwise The result after the angle.

[0084] The scanning angle and step angle of the lunar image geometric center are obtained, including the geocentric celestial coordinate system. The position of the moon under the moon, according to the coordinated universal time when the moon image was observed , using the ephemeris Calculate the moon center coordinate vector at the current moment , using the constant matrix The coordinates of the moon center are changed from Go to ;

[0085] Use interpolation algorithm to obtain the observation time Satellite positions below , calculate the moon center with the satellite mass center as the origin Coordinates in the frame , then according to Seek the Moon's Heart Next position:

[0086] ; ;

[0087] Calculate the coordinates of the moon's center of mass under the satellite sensor, by Find the sensor optical axis at Coordinates pointing down to the center of the moon , find the scanning angle where the image center is located and step angle :

[0088] ; .

[0089] The sensor optical axis locates the lunar surface point including the satellite center of mass as the origin Establish a right-handed Cartesian coordinate system, the coordinates of the moon's center of mass are , the sensor optical axis vector starts from the satellite's center of mass and points to a point on the front of the moon , solve Coordinates in right-handed Cartesian coordinate system ;

[0090] There is a Starting line , passing through point , the end point is point , There is at least one intersection with the lunar surface, and the known points Scanning angle and step angle, find the direction vector of the sensor optical axis :

[0091] ; ; ;

[0092] Will By extending the unit vector by multiples, we get Coordinates , line segment Passing point ,point and Point , line segment The parametric equation is:

[0093] ;

[0094] In the formula, is a known multiple, is the parameter to be determined of the parametric equation, yes The coordinate value of .

[0095] The sensor optical axis locates the lunar point including the lunar equation:

[0096] ;

[0097] In the formula, is the radius of the moon, , , are the three position unknowns of the lunar equation;

[0098] Line segment Substitute the parametric equation into the lunar equation:

[0099] ; ;

[0100] ; ; ;

[0101] In the formula, , , are the three coefficients of the equation, and the calculation formula is The value of the line segment The number of nodes with the Moon.

[0102] Converting the two angles of a lunar point into lunar coordinates involves converting the row and column numbers of the lunar image point into two angles:

[0103] ;

[0104] ;

[0105] In the formula, Respectively represent the row and column numbers of the moon image, Represent the two corners of the moon image, Represents the angles in the north-south and east-west directions respectively. Respectively represent the row and column numbers where the center of the lunar image is located, Respectively represent the angular sampling interval of the satellite in the north-south and east-west directions;

[0106] Will The two angles are converted into lunar points. The coordinates of the lunar point are obtained by coordinate transformation. The coordinates of:

[0107] ;

[0108] In the formula, Indicate point Fixed coordinate system on the moon The coordinates below.

[0109] The technical process of the present invention is as follows Figure 1 As shown, it includes data preparation, data processing and model construction; data preparation includes preparing satellite attitude data, lunar ephemeris data, lunar image data, satellite position and speed data; data processing includes edge detection, ellipse fitting, obtaining ellipse parameters, image cropping, Gaussian filtering, Gaussian filtering results are fed back to edge detection, ellipse fitting obtains the geometric center of the lunar image, and the ellipse parameters are used to verify the fitting results; model construction includes establishing a conversion matrix between coordinate systems, calculating the scanning angle and step angle of the image center, obtaining the full moon scanning angle and step angle, using the method of using the sensor optical axis to locate the lunar point, converting the two angles of the lunar point into lunar coordinates, and finally outputting the alignment results.

[0110] During the data preparation stage, the present invention requires two sets of lunar data in .nc format, one set contains a complete lunar image, called a full moon, and the other set contains an incomplete lunar image, such as a waxing moon, called a waning moon. Both lunar images are acquired in the visible light band. The lunar phase angle of the full moon image is 8.48°, and the lunar phase angle of the waning moon image is 45.66°. The lunar radiance data in the .nc format file is extracted. The present invention uses 5% of the maximum radiance of the lunar surface as the threshold, and regards the part below this threshold as the non-lunar part. It also uses 5% of the maximum lunar radiance as the threshold, and saves the data greater than this threshold as a csv file, which is used as the brightness value after the lunar image navigation alignment; and saves all lunar radiance data as csv data, which is used for lunar image edge detection. The present invention also requires The satellite position and velocity data under the satellite, and the ephemeris DE421 data are used to calculate the position of the moon. The satellite attitude data from the satellite orbit coordinate system to the satellite body coordinate system is used to represent the conversion relationship between the two coordinate systems.

[0111] In edge detection, the acquired .nc format lunar data is read and displayed, and the area containing part of the earth and the part affected by the earth's stray light is removed, and then saved as a .csv file. The edge detection algorithm detects integer values ​​in the range of 0-255. The lunar data is expressed in radiance and is a floating point number, so the floating point number needs to be integerized. Gaussian filtering is performed on the integer radiance value, and the filtering parameters are adjusted to remove the noise inside the moon to prevent the impact on the ellipse fitting. Then the canny edge detection operator is used to adjust the input parameters to find the best lunar detection edge. Figure 2 The moon detection edge representing the crescent moon, Figure 3 The original image representing the crescent moon, Figure 4 represents the lunar detection edge of the full moon, Figure 5 A raw image representing the full moon.

[0112] The ellipse fitting algorithm used in the present invention is based on the least squares method and will not be described in detail. After successfully extracting the edges of the full moon and the crescent moon images, they are respectively brought into the ellipse fitting algorithm to obtain the basic parameters of the fitted ellipse, such as the major and minor axes, the location of the ellipse center, and the rotation angle of the ellipse, which are represented by the red circle. Read and display the clipped lunar image, bring the obtained ellipse parameters into the ellipse equation, and then import the lunar image, where Figure 6 is the fitting result of the missing moon, Figure 7 is the fitting result of the whole moon. The geometric center of the moon image is the center of the fitted ellipse. Since the original moon data is described by row and column numbers, the geometric center of the moon image is matched to the nearest row and column number by rounding off.

[0113] Usually, the lunar data acquired by geostationary satellites have not been subjected to navigation registration and lack geometric information, such as Figure 8 As shown in , the position of the lunar image in the focal plane of the sensor is represented by row and column numbers. It is necessary to find the coordinates of the sensor optical axis pointing to the lunar surface point corresponding to the row and column numbers where the image point is located. The coordinates of the sensor optical axis vector are described by the scanning angle and step angle, as shown in Fig. 9 As shown. Finding the relationship between the optical axis vector and the coordinates of the lunar point in the lunar coordinate system can complete the geometric positioning of the lunar image. The relationship between the three can be expressed as Fig.10 A simple expression is the relationship between row and column numbers, two angles and longitude and latitude.

[0114] The distance between the moon and the satellite is about 400,000 kilometers, and the distance between the satellite sensor center of mass and the satellite center of mass is less than 10 meters. Therefore, this article does not consider the difference between the satellite sensor coordinate system and the satellite body coordinate system. Since the distance between the sensor focus and the satellite center of mass is too small relative to the distance between the satellite and the moon, it can be ignored. When the judgment formula is less than 0, the equation has no solution, indicating that there is no intersection with the moon. When the judgment formula is greater than 0, there are two intersections, namely the intersection facing the satellite and the intersection on the back of the moon. The smallest value represents the intersection of the moon facing the satellite. When the judgment formula is equal to 0, there is a unique intersection. The sensors of the geostationary satellite have different angular sampling intervals in different bands. Select the angular sampling intervals of the corresponding bands in the north-south and east-west directions to calculate the two angular positions of the entire lunar image points.

[0115] like Fig.11 As shown, first As a unified coordinate system for calculation, Convert the unit vector of the lunar point in the satellite coordinate system to , all image points are brought into the method flow for judgment. When the equation has no solution, it means that the image point is not a real lunar surface point. When there is at least one solution, we get The intersection of the direction vector of the lunar point and the lunar surface is finally obtained through vector calculation. The coordinates of the next lunar point are obtained using and The rotation matrix between ,Will The next lunar point goes to In the process, the geometric positioning of lunar points is realized. Fig.12 The calculation result for a crescent moon is Fig.13 The result of the calculation for a full moon is Fig.12 The moon phase angle is 45.66 degrees. Fig.13 The lunar phase angle is 8.48 degrees. The longitude and latitude ranges of the two lunar images are consistent in characteristic areas such as large-area impact craters such as Tycho Crater, and the converted images are consistent with the actual lunar images.

[0116] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some or all of the technical features may be replaced by equivalents, and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A geostationary satellite lunar image navigation registration method based on geometric position precise calculation, characterized in that: Including data preparation, data processing and model building; Data preparation includes preparing satellite attitude data, lunar ephemeris data, lunar image data, satellite position and velocity data; Data processing includes edge detection, ellipse fitting, obtaining ellipse parameters, image cropping, and Gaussian filtering. The Gaussian filtering result is fed back to edge detection, the geometric center of the lunar image is obtained by ellipse fitting, and the ellipse parameters are used to verify the fitting results. The model construction includes establishing the transformation matrix between the coordinate systems, calculating the scanning angle and step angle of the image center, obtaining the full moon scanning angle and step angle, using the method of locating the lunar point using the sensor optical axis, converting the two angles of the lunar point into lunar coordinates, and finally outputting the registration results; Converting the two angles of a lunar point into lunar coordinates involves converting the row and column numbers of the lunar image point into two angles: ； ； In the formula, Respectively represent the row and column numbers of the moon image, Represent the two corners of the moon image, Represents the angles in the north-south and east-west directions respectively. Respectively represent the row and column numbers where the center of the lunar image is located, Represents the angular sampling interval of the satellite in the north-south and east-west directions respectively.

2. The method for geostationary satellite lunar image navigation registration based on geometric position precise calculation according to claim 1, characterized in that: Establishing the transformation matrix between coordinate systems includes establishing the satellite orbit coordinate system To the inertial coordinate system The rotation matrix , Satellite body coordinate system To the satellite orbit coordinate system The rotation matrix , Satellite body coordinate system To the inertial coordinate system The rotation matrix , Inertial coordinate system Fixed coordinate system to the moon The rotation matrix .

3. The method for geostationary satellite lunar image navigation registration based on geometric position precise calculation according to claim 2 is characterized in that: Establishing satellite orbit coordinate system To the inertial coordinate system The rotation matrix include: ； ； ； ； In the formula, and Satellites in The position and velocity vectors are , , are the components of the rotation matrix in three dimensions.

4. The method for geostationary satellite lunar image navigation registration based on geometric position precise calculation according to claim 3 is characterized in that: Establishing the satellite coordinate system To the satellite orbit coordinate system The rotation matrix include: ； ； ； ； In the formula, , , denote the roll angle, pitch angle and yaw angle respectively, , , Respectively The three coordinate axes rotate counterclockwise , , The result after the angle.

5. The method for geostationary satellite lunar image navigation registration based on geometric position precise calculation according to claim 4, characterized in that: Establishing the satellite coordinate system To the inertial coordinate system The rotation matrix include: 。 6. The method for geostationary satellite lunar image navigation registration based on geometric position precise calculation according to claim 5, characterized in that: Establishing an inertial coordinate system Fixed coordinate system to the moon The rotation matrix include: ； In the formula, , , are the three lunar libration parameters of the Moon relative to the International Celestial Reference Frame, for of Coordinate axis rotates counterclockwise The result after the angle, for of Coordinate axis rotates counterclockwise The result after the angle, for of Coordinate axis rotates counterclockwise The result after the angle.

7. The method for geostationary satellite lunar image navigation registration based on geometric position precise calculation according to claim 6, characterized in that: The scanning angle and step angle of the lunar image geometric center are obtained, including the geocentric celestial coordinate system. The position of the moon under the moon, according to the coordinated universal time when the moon image was observed , using the ephemeris Calculate the moon center coordinate vector at the current moment , using the constant matrix The coordinates of the moon center are changed from Go to ; Use interpolation algorithm to obtain the observation time Satellite positions below , calculate the moon center with the satellite mass center as the origin Coordinates in the frame , then according to Seek the Moon's Heart Next position: ； ； Calculate the coordinates of the moon's center of mass under the satellite sensor, by Find the sensor optical axis at Coordinates pointing down to the center of the moon , find the scanning angle where the image center is located and step angle : ； 。 8. The method for geostationary satellite lunar image navigation registration based on geometric position precise calculation according to claim 7, characterized in that: The sensor optical axis locates the lunar surface point including the satellite center of mass as the origin Establish a right-handed Cartesian coordinate system, the coordinates of the moon's center of mass are , the sensor optical axis vector starts from the satellite's center of mass and points to a point on the front of the moon , solve Coordinates in right-handed Cartesian coordinate system ; There is a self Starting line , passing through point , the end point is , There is at least one intersection with the lunar surface, and the known points Scanning angle and step angle, find the direction vector of the sensor optical axis : ； ； ； Will By extending the unit vector by multiples, we get Coordinates , line segment Passing point ,point and Point , line segment The parametric equation is: ； In the formula, is a known multiple, is the parameter to be determined of the parametric equation, yes The coordinate value of .

9. The method for geostationary satellite lunar image navigation registration based on geometric position precise calculation according to claim 8, characterized in that: The sensor optical axis locates the lunar point including the lunar equation: ； In the formula, is the radius of the moon, , , are the three position unknowns of the lunar equation; Line segment Substitute the parametric equation into the lunar equation: ； ； ； ； ； In the formula, , , are the three coefficients of the equation, and the calculation formula is The value of the line segment The number of nodes with the Moon.

10. The method for geostationary satellite lunar image navigation registration based on geometric position precise calculation according to claim 9, characterized in that: Will The two angles are converted into lunar points. The coordinates of the lunar point are obtained by coordinate transformation. The coordinates of: ； In the formula, Indicate point Fixed coordinate system on the moon The coordinates below.

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