CN111156990B - Space debris real-time astronomical positioning and photometry method based on automatic pointing determination - Google Patents

Space debris real-time astronomical positioning and photometry method based on automatic pointing determination Download PDF

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CN111156990B
CN111156990B CN201911416733.2A CN201911416733A CN111156990B CN 111156990 B CN111156990 B CN 111156990B CN 201911416733 A CN201911416733 A CN 201911416733A CN 111156990 B CN111156990 B CN 111156990B
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space debris
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张晓祥
高昕
李希宇
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Purple Mountain Observatory of CAS
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Abstract

本发明公开了一种基于指向自动测定的空间碎片实时天文定位和测光方法，包括：理论星图生成；恒星及空间碎片星象；实测星图生成；理论星图及实测星图匹配；指向及像面旋转测定；恒星检索；底片模型优选；测光模型计算；空间碎片天文定位和测光。本发明能够根据观测视场大小自动优选底片模型，按照图像上给定时间，自动测定图像中心指向及像面旋转角，实现恒星理论坐标和实测坐标的自动匹配，实现图像上恒星灰度值和其理论星等的自动匹配，从而实现空间碎片的实时天文定位及测光。

Figure 201911416733

The invention discloses a real-time astronomical positioning and photometric method for space debris based on automatic pointing determination, including: theoretical star map generation; star and space debris star images; measured star map generation; theoretical star map and measured star map matching; Determination of image plane rotation; star retrieval; film model optimization; photometric model calculation; space debris astronomical positioning and photometry. The invention can automatically select the film model according to the size of the observation field, and automatically measure the center point of the image and the rotation angle of the image plane according to the given time on the image, realize the automatic matching of the theoretical coordinates of the stars and the measured coordinates, and realize the gray value and the gray value of the stars on the image. The automatic matching of its theoretical magnitude enables real-time astronomical positioning and photometry of space debris.

Figure 201911416733

Description

Space debris real-time astronomical positioning and photometry method based on automatic pointing determination
Technical Field
The invention relates to the technical field of space debris positioning, in particular to a space debris real-time astronomical positioning and photometry method based on automatic pointing determination.
Background
In many fields such as scientific research, military affairs and the like, space debris needs to be monitored, on one hand, the position and the change of the space debris in the sky at each observation moment are measured, the operation track of the space debris is determined, and therefore accurate information of the space debris is obtained. Based on the requirement, the accurate measurement of the space debris is a very important basic link, and the accurate measurement of the space debris is not available, and the track identification, the cataloging and the rail fixing of the space debris and the precise rail fixing of the space debris cannot be realized.
There are two methods for accurately measuring the position of space debris: the method comprises absolute positioning and relative positioning, wherein the absolute positioning is to realize space debris measurement by using a telescope axis system, is influenced by factors such as telescope axis system processing precision, atmospheric refraction correction precision, temperature deformation and the like, and does not depend on a background fixed star. The relative positioning is to realize the measurement of the space debris according to the relative position of the space debris and the background fixed star, the pointing accuracy of the telescope does not directly influence the measurement result, but under the condition that the pointing direction of the telescope and the installation error of the image surface are large, the difference between the theoretical coordinate of the fixed star on the image and the actually measured coordinate of the fixed star on the image is large, especially for the image with the error of the image surface, the error of the edge part is large, the given matching threshold cannot be met, so the matching failure of the theoretical star map and the actually measured star map of the fixed star is caused, and the relative positioning cannot.
There are also two methods for photometric accurate measurement of space debris: absolute measurement and relative measurement. The method comprises the following steps that a plurality of standard photometry calibration stars in different fields of view are utilized to obtain a photometry model, which is called an absolute measurement model and is also called absolute photometry; the light metering model obtained by using a plurality of light metering calibration stars in the same field of view is called as a relative measurement model, and is also called as relative light metering. In any light measuring mode, the method is based on the fact that actually measured gray scales of fixed stars and the matching with theoretical stars of fixed stars are successful, and the accurate temperature, relative humidity and atmospheric pressure of a measuring station are needed. Even in such a case, in an area of low elevation, the correction accuracy of the atmospheric refraction is affected, and the correction accuracy of the pointing error of the telescope is low.
Based on the defects of the existing astronomical positioning method, the invention provides a space target real-time astronomical positioning method based on automatic direction determination, which can automatically select a negative film model according to the size of an observation field, automatically determine the direction of the center of an image and the rotation angle of an image surface according to the given time and the direction of the center of the image without direction information input, and realize the automatic matching of a fixed star theoretical coordinate and an actually measured coordinate, thereby realizing the real-time astronomical positioning and photometry of space debris.
Disclosure of Invention
The invention aims to provide a space debris real-time astronomical positioning and photometry method based on automatic direction measurement, which can automatically select a negative film model according to the size of an observation field, automatically measure the center direction and the image surface rotation angle of an image according to the given time on the image, realize the automatic matching of a fixed star theoretical coordinate and an actually measured coordinate, realize the automatic matching of a fixed star gray value and a theoretical star thereof on the image, and further realize the real-time astronomical positioning and photometry of the space debris. For a telescope with a fixed station address (with precise astronomical longitude and latitude), the method reduces the requirement on the machining precision of a telescope axis, reduces the requirement on the installation and debugging of an external field of the telescope, reduces the requirement on the environmental temperature reference input of a survey station, and reduces the requirement on pointing calibration before observation. For a movable telescope, the method can automatically measure the zero point difference of two axes of the telescope and can also realize real-time astronomical positioning and relative photometry of space debris under the condition that pointing calibration of the telescope cannot be realized without precise astronomical longitude and latitude. More importantly, the method can realize high-precision astronomical positioning and relative photometry on a mobile station site without astronomical longitude and latitude (only geographical longitude and latitude).
To achieve the above object, with reference to fig. 1, the present invention provides a real-time astronomical positioning and light measuring method for space debris based on automatic pointing measurement, wherein the real-time astronomical positioning and light measuring method comprises the following steps:
s1: generating an astronomical positioning fixed star library and first index data for expressing self information of all fixed stars contained in the astronomical positioning fixed star library; generating a whole-day-area theoretical star map and second index data for expressing angular distance information between stars contained in the whole-day-area theoretical star map based on an astronomical positioning star library;
s2: receiving at least one frame of image comprising space debris and background stars, and obtaining star image information of the stars and the space debris on the image within a preset detection threshold; calculating to obtain the angular distance between any two fixed stars based on the obtained star image information of the fixed stars, and generating a fixed star actual measurement star map;
s3: according to the theoretical star map of the whole day region and the second index data, the upper and lower limits of the actually measured star map of the fixed star are determined, and the maximum angular distance is obtained
Figure BDA0002351384770000021
Minimum angular distance
Figure BDA0002351384770000022
Intermediate angular distance
Figure BDA0002351384770000023
Combined maximum angular distance
Figure BDA0002351384770000024
Minimum angular distance
Figure BDA0002351384770000025
Intermediate angular distance
Figure BDA0002351384770000026
According to a preset matching rule, calculating to obtain a plurality of fixed star planets which are contained in an actually measured fixed star atlas and are matched with a theoretical star atlas of an all-day area;
s4: calculating to obtain center pointing deviation, image surface rotation angle, negative film constant model and relative photometric model based on the successfully matched star image information;
wherein, the photometry model is:
Figure BDA0002351384770000027
wherein G isiThe gray value of the ith successfully matched star-star image after background subtraction,
Figure BDA0002351384770000028
is a theoretical star corresponding to the ith successfully matched star-star image, i is 1,2, …, N3，N3Is the total number of successfully matched star stars, and A and B are relative photometric model coefficients calculated by a least square method.
In a further embodiment, in step S2, the process of generating the measured star map of the fixed star includes the following steps:
selecting N from the image according to a given threshold1The star image of the fixed star is defined as a first candidate fixed star, the angular distance between any two first candidate fixed stars is obtained through calculation by combining the two-dimensional plane coordinates of the first candidate fixed star on the image and the focal length of the telescope, three first candidate fixed stars are selected to form a triangular star map, and a fixed star actual measurement star map is generated;
the angular distance between any two first candidate stars is calculated by adopting the following formula:
Figure BDA0002351384770000029
where f is the focal length of the telescope, (x)j,yj) Is the two-dimensional plane coordinate of the jth first candidate star, (x)k,yk) Is the two-dimensional plane coordinates of the kth first candidate star.
In a further embodiment, in step S1, the generating an astronomical positioning star base and the first index data for describing all star self information included in the astronomical positioning star base includes:
and storing the fixed stars in the whole day area of the given star and the like in a partitioning manner according to the increasing order of the right ascension and the increasing order of the declination, forming an index, and generating an astronomical positioning fixed star library and index data.
In a further embodiment, in step S1, the generating of the all-day-region theoretical star map and the second index data used for expressing the angular distance information between stars included in the all-day-region theoretical star map based on the astronomical positioning star library includes:
selecting a whole day region N according to a given star equal threshold2And the particle star elephant is defined as a second candidate star, the angular distance between any two second candidate stars is obtained through calculation by combining the right ascension and the declination of the second candidate stars, a triangular star map is formed by optionally selecting three second candidate stars according to a given angular distance threshold, a theoretical star map of the whole day area is generated, and the theoretical star map is sorted according to the angular distance of each triangle to generate corresponding index data.
In a further embodiment, in step S1, the angular distance between any two second candidate stars is calculated by the following formula:
Figure BDA0002351384770000031
wherein (alpha)u,δu) Is the right ascension and declination of the u-th second candidate star, (alpha)v,δv) Is the right ascension and declination, σ, of the v-th second candidate starc u,vIs the angular distance between the u-th and v-th second candidate stars.
In a further embodiment, in step S3, the step of calculating, according to a preset matching rule, a plurality of pieces of star stellar information which are included in the actually measured star atlas of the fixed star and are matched with the theoretical star atlas of the whole sky area includes the following steps:
s31: determining the upper and lower limits of the candidate star atlas according to the all-day area theoretical star atlas and the second index data, and acquiring the maximum angular distance
Figure BDA0002351384770000032
Minimum angular distance
Figure BDA0002351384770000033
Intermediate angular distance
Figure BDA0002351384770000034
S32: sequentially calculating the angular distance of a triangle formed by any three calibration stars i, j and k in the upper and lower boundaries, and setting the sequence of the calculated angular distances from large to small as
Figure BDA0002351384770000035
According to the following matching conditions, the calculated angular distance is calculated
Figure BDA0002351384770000036
Correspond to
Figure BDA0002351384770000037
Figure BDA0002351384770000038
Carrying out matching judgment until the matching is successful N3Particle fixed stars:
the jth scaling star and the kth scaling star satisfy the following formula:
Figure BDA0002351384770000039
the following formula is satisfied between any three i, j, k calibration stars:
Figure BDA00023513847700000310
wherein epsilon1And ε2All are preset angular distance thresholds;
in a further embodiment, in step S4, the process of calculating the center pointing deviation and the image plane rotation angle based on the information of the plurality of star planets successfully matched includes the following steps:
n for successful design matching3The two-dimensional plane coordinate of the particle fixed star on the image is (x)i,yi)，i＝1,2,…N3The corresponding theoretical two-dimensional plane coordinate is (X)i,Yi)，i＝1,2,…N3；
Calculating coefficients a, b, c, d, e and f by using a least square method according to the following formula, so as to obtain a center pointing deviation and an image plane rotation angle:
Figure BDA0002351384770000041
in a further embodiment, in step S4, the acquiring process of the negative film constant model includes the following steps:
combining the astronomical positioning fixed star library and the first index data, and according to the shooting information corresponding to the image and the whole-day star map pointing measurement result (alpha)p,δp) Retrieving relevant information of all fixed stars meeting a given star equal threshold in the field of view, wherein the relevant information of the fixed stars meeting the given star equal threshold comprises corresponding two-dimensional plane coordinate theoretical values (X, Y), right ascension and declination theoretical values (alpha)s,δs) Ideal coordinate theoretical value (xi)s,ζs) The M such as theoretical stars and the like sort the searched fixed stars according to the sequence from small to large of the theoretical stars and the like; wherein the ideal coordinates (ξ)s,ζs) The following formula is satisfied:
Figure BDA0002351384770000042
the shooting information corresponding to the image comprises shooting time of the image, pointing information, longitude and latitude of the measuring station, altitude of the measuring station, temperature of the measuring station, humidity of the measuring station, atmospheric pressure and given view field size;
combining the successfully matched N according to the size of the corresponding view field of the image3Two-dimensional plane coordinate (x) of particle fixed star on imagei,yi) And ideal coordinates
Figure BDA0002351384770000043
i＝1,2,…N3And calculating a constant model, automatically optimizing the film constant model according to the positioning accuracy of the fixed star, and automatically storing the optimized film constant model.
In a further embodiment, said performing constant model calculations comprises,
and (3) combining the number of successfully matched calibration stars, and respectively selecting a six-constant model, a twelve-constant model and a fourteen-constant model for constant model calculation, wherein:
the six-constant model corresponds to at least 3 calibration stars:
Figure BDA0002351384770000044
the twelve constant model corresponds to at least 6 calibration stars:
Figure BDA0002351384770000045
the fourteen-constant model corresponds to at least 7 calibration stars:
Figure BDA0002351384770000046
in a further embodiment, the real-time astronomical positioning method further comprises:
s5: according to the two-dimensional plane coordinate measured value (x) of the space debrisT,yT) Is adopted toThe following formula obtains the right ascension and declination (alpha) of the space debrisT,δT)：
Figure BDA0002351384770000051
Wherein (xi)T,ζT) Is the ideal coordinate of space debris, consisting ofT,yT) And substituting a six-constant model, a twelve-constant model or a fourteen-constant model to obtain the model.
Compared with the prior art, the technical proposal of the invention has the obvious beneficial effects that,
(1) the negative film model can be automatically optimized according to the size of an observation view field, the image center pointing direction and the image surface rotation angle are automatically measured according to the given time and the image center pointing direction on the image, and the automatic matching of the fixed star theoretical coordinate and the actual measurement coordinate is realized, so that the real-time astronomical positioning and photometry of space debris are realized.
(2) For a telescope with a fixed station address (with precise astronomical longitude and latitude), the method reduces the requirement on the machining precision of a telescope axis, reduces the requirement on the installation and debugging of an external field of the telescope, reduces the requirement on the environmental temperature reference input of a survey station, and reduces the requirement on pointing calibration before observation. For the movable telescope, the method can realize real-time astronomical positioning and relative photometry of space debris under the condition that pointing calibration of the telescope cannot be realized without precise astronomical longitude and latitude. Therefore, the method is a very good space debris real-time astronomical positioning and light measuring method.
(3) The method can realize high-precision astronomical positioning and relative photometry on a mobile station site without astronomical longitude and latitude (only geographical longitude and latitude), has good actual processing effect, and can be widely applied to the fields of scientific research and engineering.
(4) The computer system can give space debris astronomical positioning results, fixed star astronomical positioning results, pointing image plane rotation measuring results and fixed star retrieval results on the images in real time. The results are widely applied, for example, the results can be displayed by a display system, stored in a storage medium of a computer system, used for cataloging and precisely tracking the space debris, and corrected according to the pointing measurement result, so that the capturing and tracking success rate of the space debris can be improved.
It should be understood that all combinations of the foregoing concepts and additional concepts described in greater detail below can be considered as part of the inventive subject matter of this disclosure unless such concepts are mutually inconsistent. In addition, all combinations of claimed subject matter are considered a part of the presently disclosed subject matter.
The foregoing and other aspects, embodiments and features of the present teachings can be more fully understood from the following description taken in conjunction with the accompanying drawings. Additional aspects of the present invention, such as features and/or advantages of exemplary embodiments, will be apparent from the description which follows, or may be learned by practice of specific embodiments in accordance with the teachings of the present invention.
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The drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component that is illustrated in various figures may be represented by a like numeral. For purposes of clarity, not every component may be labeled in every drawing. Embodiments of various aspects of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which:
fig. 1 is a flow chart of the space debris real-time astronomical positioning and light measuring method based on automatic pointing determination of the present invention.
Detailed Description
In order to better understand the technical content of the present invention, specific embodiments are described below with reference to the accompanying drawings.
With reference to fig. 1, the present invention provides a real-time astronomical positioning and photometry method for space debris based on automatic pointing measurement, comprising the following steps:
s1: generating an astronomical positioning fixed star library and first index data for expressing self information of all fixed stars contained in the astronomical positioning fixed star library; and generating a whole-day-region theoretical star map and second index data for expressing the angular distance information between the stars contained in the whole-day-region theoretical star map based on the astronomical positioning star library.
S2: receiving at least one frame of image comprising space debris and background stars, and obtaining star image information of the stars and the space debris on the image within a preset detection threshold; and calculating to obtain the angular distance between any two fixed stars based on the acquired star image information of the fixed stars, and generating the actually measured star map of the fixed stars.
S3: according to the theoretical star map of the whole day region and the second index data, the upper and lower limits of the actually measured star map of the fixed star are determined, and the maximum angular distance is obtained
Figure BDA0002351384770000061
Minimum angular distance
Figure BDA0002351384770000062
Intermediate angular distance
Figure BDA0002351384770000063
Combined maximum angular distance
Figure BDA0002351384770000064
Minimum angular distance
Figure BDA0002351384770000065
Intermediate angular distance
Figure BDA0002351384770000066
And according to a preset matching rule, calculating to obtain a plurality of fixed star planets which are contained in the fixed star actual measurement star atlas and are matched with the all-day area theoretical star atlas.
S4: and calculating to obtain center pointing deviation, image surface rotation angle, negative film constant model and relative photometric model based on the information of a plurality of star planets successfully matched.
Wherein, the photometry model is:
Figure BDA0002351384770000067
wherein G isiIs that the ith matching is successfulThe gray value of the star-star image after deducting the background,
Figure BDA0002351384770000068
is a theoretical star corresponding to the ith successfully matched star-star image, i is 1,2, …, N3，N3Is the total number of successfully matched star stars, and A and B are relative photometric model coefficients calculated by a least square method.
Briefly, the technical scheme of the invention comprises the following working steps:
(1) and generating a theoretical star map.
(2) Stars and space debris stars.
(3) And generating an actual measurement star map.
(4) And matching the theoretical star map with the actual measurement star map.
(5) And measuring the direction and the image plane rotation.
(6) And (5) searching stars.
(7) The negative model is preferred.
(8) And (5) calculating a photometric model.
(9) Space debris astronomical localization.
In practical application, after acquiring star image information of stars and space debris on each frame of image through space target detection aiming at the collected continuous observation images, the 9 steps are sequentially adopted to acquire astronomical positioning and photometric data of the space debris. More optimally and more specifically describing the above steps as follows:
first, theoretical star map generation
And storing the stars in all-day regions of the given star and the like in a partitioning manner according to the increasing order of the right ascension and the increasing order of the declination, forming an index, and generating an astronomical positioning star database and first index data for searching the stars. Selecting a whole day region N according to a given star equal threshold2The star image of the particle stars calculates the angular distance between any two fixed stars by adopting the following formula according to the information of the right ascension and the declination of the fixed stars:
Figure BDA0002351384770000071
wherein (alpha)u,δu) Is the right ascension and declination of the u-th second candidate star, (alpha)v,δv) Is the right ascension and declination of the v second candidate star
And according to a given threshold, such as minimum and maximum angular distances, optionally selecting three stars to form a triangular star map, generating a theoretical star map of the whole sky area, and sorting according to the angular distance of each triangle. And generating a theoretical star atlas database of the whole day area and corresponding second index data for star atlas retrieval.
Second, fixed star and space debris astrology
According to the space debris detection method, star image information of stars and space debris on an image within a detection threshold is obtained, wherein the star image information comprises two-dimensional plane coordinates (x, y), the number of pixels, the gray sum, and the image is sorted according to the decreasing sequence of the number of pixels. Preferably, any space debris acquisition method in the prior art can be adopted to obtain star image information of stars and space debris within the detection threshold on the image. The left upper corner of the image is set as a coordinate origin (0, 0), the right side of the image is set as an x-axis increasing direction, the lower side of the image is set as a y-axis increasing direction, x is the distance between the position of the star in the image and the coordinate origin in the x-axis direction, and y is the distance between the position of the star in the image and the coordinate origin in the y-axis direction.
Third, actual measurement star map generation
According to a given threshold, selecting N1The focal length of the telescope is f according to the two-dimensional plane coordinates (x, y) of the star image of the fixed star. The angular distance between any two fixed stars is calculated by adopting the following formula, and three fixed stars are selected by people to form a triangular star map so as to generate an actual measurement star map of the fixed stars. Calculating the angular distance between any two first candidate stars by adopting the following formula:
Figure BDA0002351384770000072
wherein (x)j,yj) Is the two-dimensional plane coordinate of the jth second candidate star, (x)k,yk) Is the k second candidate starPlane coordinates.
Fourthly, matching the theoretical star map with the actual measurement star map
For any three calibration stars i, j, k on the image, the angular distance is formed in the order of magnitude
Figure BDA0002351384770000073
The triangles of (1) quickly realize the upper and lower boundaries n of the candidate star atlas according to the index of the theoretical star atlas, and the corresponding angular distances of the triangles in the upper and lower boundaries are in the order of magnitude
Figure BDA0002351384770000074
Figure BDA0002351384770000075
And (6) carrying out matching judgment.
Since f may not be too accurate, the relationship between the jth and kth calibration stars can still satisfy the following equation:
Figure BDA0002351384770000076
the following formula is satisfied between any three i, j, k calibration stars:
Figure BDA0002351384770000077
and
Figure BDA0002351384770000078
and fifthly, measuring the direction and the image plane rotation.
Suppose the matching is successful N3Fixed star, two-dimensional plane coordinate (x) of star on imagei,yi)，i＝1,2,…N3Theoretical two-dimensional planar coordinate (X) of a star imagei,Yi)，i＝1,2,…N3。
Calculating coefficients a, b, c, d, e and f by using a least square method according to the following formula, so as to obtain a center pointing deviation and an image plane rotation angle:
Figure BDA0002351384770000081
sixthly, searching stars.
According to the time corresponding to the image and the whole-day star map orientation measurement result (alpha)p,δp) The method comprises the steps of searching fixed star information which meets thresholds such as a given star and the like in a view field and comprises two-dimensional plane coordinate theoretical values (X, Y), right ascension and declination theoretical values (alpha)s,δs) Ideal coordinate theoretical value (xi)s,ζs) M such as theoretical stars and the like, and sequencing according to the increasing sequence of the theoretical stars and the like. The ideal coordinate (xi)s,ζs) The following formula is satisfied:
Figure BDA0002351384770000082
seventh, the negative film model is preferred.
According to the size of the corresponding field of view of the image, the matching is assumed to be successful N3Fixed star, two-dimensional plane coordinate (x) of star on imagei,yi) And ideal coordinates
Figure BDA0002351384770000083
i＝1,2,…N3. And (4) automatically optimizing the negative constant model according to the positioning precision of the fixed star by adopting the following six-constant, twelve-constant and fourteen-constant model calculation (the optimization is only needed once, and the optimization result is automatically stored).
Six constant model (need more than 3 calibration stars)
Figure BDA0002351384770000084
Twelve constant model (requiring more than 6 calibration stars)
Figure BDA0002351384770000085
Fourteen constant model (requiring more than 7 calibration stars)
Figure BDA0002351384770000086
Eight, photometric model calculation
Suppose the matching is successful N3The gray value of the particle star and the star image minus the background is GiAnd the corresponding theoretical star, etc. is Mi c，i＝1,2,…,N3. Relative photometric model coefficients a and B were obtained using the following formula using the least squares method:
Mi c＝Α+B log(Gi). LOG has 10 subscripts
And ninthly, astronomical positioning of the space debris.
According to the two-dimensional plane coordinate measured value (x) of the space debrisT,yT) The right ascension and declination (alpha) of the space debris are obtained using the following formulaT,δT)：
Figure BDA0002351384770000091
Wherein (xi)T,ζT) Is the ideal coordinate of space debris, consisting ofT,yT) And substituting a six-constant model, a twelve-constant model or a fourteen-constant model to obtain the model.
And the computer system provides space debris astronomical positioning and light measuring results, fixed star astronomical positioning and light measuring results, pointed image plane rotation measuring results and fixed star retrieval results on the image in real time according to the input data. The results can be displayed by a display system, stored in a storage medium of a computer system, used for cataloging, orbit determination and precise orbit determination of the space debris, and the forecast positions of the space debris can be corrected according to the pointing measurement result, so that the capturing and tracking success rate of the space debris can be improved; the method can be used for space debris identification, and can be used for evaluating the working state, the rotating state and the like of the attitude control space target.
In this disclosure, aspects of the present invention are described with reference to the accompanying drawings, in which a number of illustrative embodiments are shown. Embodiments of the present disclosure are not necessarily defined to include all aspects of the invention. It should be appreciated that the various concepts and embodiments described above, as well as those described in greater detail below, may be implemented in any of numerous ways, as the disclosed concepts and embodiments are not limited to any one implementation. In addition, some aspects of the present disclosure may be used alone, or in any suitable combination with other aspects of the present disclosure.
Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, the protection scope of the present invention should be determined by the appended claims.

Claims (9)

1.一种基于指向自动测定的空间碎片实时天文定位和测光方法，其特征在于，所述实时天文定位和测光方法包括以下步骤：1. A real-time astronomical positioning and photometric method of space debris based on pointing to automatic determination, is characterized in that, described real-time astronomical positioning and photometric method comprises the following steps: S1：生成天文定位恒星星库、和用于表述天文定位恒星星库所包含的所有恒星自身信息的第一索引数据；基于天文定位恒星星库，生成全天区理论星图、和用于表述全天区理论星图所包含的恒星之间角距信息的第二索引数据；S1: Generate the astronomical positioning star database and the first index data used to express the information of all the stars included in the astronomical positioning star database; The second index data of the angular distance information between stars contained in the theoretical star map of the whole sky area; S2：接收至少一帧包括空间碎片和背景恒星的图像，获得图像上在预设检测门限内的恒星和空间碎片的星象信息；基于获取的恒星星象信息，计算得到任意两颗恒星之间的角距，生成恒星实测星图；S2: Receive at least one frame of images including space debris and background stars, and obtain astrological information of stars and space debris within the preset detection threshold on the image; based on the obtained stellar constellation information, calculate the angle between any two stars distance, to generate the measured star map of the stars; S3：根据全天区理论星图和第二索引数据，确定恒星实测星图的上下界限，获取最大角距
Figure FDA0002864364240000011
最小角距
Figure FDA0002864364240000012
中间角距
Figure FDA0002864364240000013
结合最大角距
Figure FDA0002864364240000014
最小角距
Figure FDA0002864364240000015
中间角距
Figure FDA0002864364240000016
按照预设的匹配规则，计算得到恒星实测星图中所包含的与全天区理论星图相匹配的若干个恒星星象；S3: According to the theoretical star map of the whole sky area and the second index data, determine the upper and lower limits of the actual star map of the star, and obtain the maximum angular distance
Figure FDA0002864364240000011
Minimum angular distance
Figure FDA0002864364240000012
Intermediate angular distance
Figure FDA0002864364240000013
Combine the maximum angular distance
Figure FDA0002864364240000014
Minimum angular distance
Figure FDA0002864364240000015
Intermediate angular distance
Figure FDA0002864364240000016
According to the preset matching rules, calculate and obtain several stellar images contained in the observed star map that match the theoretical star map of the whole sky area; S4：以匹配成功的若干个恒星星象信息为基础，计算得到中心指向偏差、像面旋转角、底片常数模型、测光模型；S4: Based on the information of several successfully matched stars, the center pointing deviation, the rotation angle of the image plane, the film constant model, and the photometric model are calculated; 其中，测光模型为：Among them, the metering model is:
Figure FDA0002864364240000017
Figure FDA0002864364240000017
 其中，Gi是第i颗匹配成功的恒星星象扣除背景后的灰度值，
Figure FDA0002864364240000018
是第i颗匹配成功的恒星星象对应的理论星等，i＝1,2,…,N3，N3是匹配成功的恒星星象的总数，Α和B是采用最小二乘法计算得到的测光模型系数；Among them, G i is the gray value of the i-th successfully matched star after deducting the background,
Figure FDA0002864364240000018
is the theoretical magnitude corresponding to the i-th successfully matched stellar image, i=1,2,...,N 3 , N 3 is the total number of successfully matched stellar images, Α and B are the photometry calculated by the least square method model coefficients; 所述实时天文定位方法还包括：The real-time astronomical positioning method further includes: S5：根据空间碎片的二维平面坐标实测值(xT,yT)，采用以下公式获得空间碎片的赤经和赤纬(αT,δT)：S5: According to the measured values of the two-dimensional plane coordinates of the space debris (x T , y T ), use the following formula to obtain the right ascension and declination (α T , δ T ) of the space debris:
Figure FDA0002864364240000019
Figure FDA0002864364240000019
 其中，(ξT,ζT)为空间碎片的理想坐标，由(xT,yT)代入六常数、十二常数或者十四常数模型获得。Among them, (ξ T , ζ T ) are the ideal coordinates of space debris, obtained by substituting (x T , y T ) into the six-constant, twelve-constant or fourteen-constant model. 2.根据权利要求1所述的基于指向自动测定的空间碎片实时天文定位和测光方法，其特征在于，步骤S2中，所述生成恒星实测星图的过程包括以下步骤：2. The method for real-time astronomical positioning and photometry of space debris based on automatic determination of pointing according to claim 1, wherein in step S2, the process of generating a measured star map of stars comprises the following steps: 按照给定门限，从图像中选择N1颗恒星星象，定义成第一候选恒星，结合第一候选恒星在图像上的二维平面坐标和望远镜的焦距，计算得到任意两颗第一候选恒星之间的角距，选择三颗第一候选恒星组成三角形星图，生成恒星实测星图；According to a given threshold, select N 1 stellar images from the image and define them as the first candidate star. Combined with the two-dimensional plane coordinates of the first candidate star on the image and the focal length of the telescope, the calculation of the difference between any two first candidate stars is calculated. The angular distance between the three first candidate stars is selected to form a triangular star map, and the measured star map of the stars is generated; 其中，采用下述公式计算任意两颗第一候选恒星之间的角距：Among them, the following formula is used to calculate the angular distance between any two first candidate stars:
Figure FDA00028643642400000110
Figure FDA00028643642400000110
 其中，f是望远镜的焦距，(xj,yj)是第j颗第一候选恒星的二维平面坐标，(xk,yk)是第k颗第一候选恒星的二维平面坐标。Among them, f is the focal length of the telescope, (x j , y j ) is the two-dimensional plane coordinate of the jth first candidate star, (x k , y k ) is the two-dimensional plane coordinate of the kth first candidate star. 3.根据权利要求1所述的基于指向自动测定的空间碎片实时天文定位和测光方法，其特征在于，步骤S1中，所述生成天文定位恒星星库、和用于表述天文定位恒星星库所包含的所有恒星自身信息的第一索引数据是指，3. The real-time astronomical positioning and photometric method for space debris based on automatic determination of pointing according to claim 1, wherein in step S1, the generation of the astronomical positioning star library and the method for expressing the astronomical positioning star library The first index data that contains all the star's own information refers to, 将给定星等的全天区恒星按照赤经增加及赤纬增加的顺序分区存放，并形成索引，生成天文定位恒星星库及索引数据。All-sky stars of a given magnitude are stored in partitions in the order of increasing right ascension and increasing declination, and form an index to generate astronomical positioning star library and index data. 4.根据权利要求1所述的基于指向自动测定的空间碎片实时天文定位和测光方法，其特征在于，步骤S1中，所述基于天文定位恒星星库，生成全天区理论星图、和用于表述全天区理论星图所包含的恒星之间角距信息的第二索引数据是指，4. The real-time astronomical positioning and photometric method of space debris based on automatic determination of pointing according to claim 1, is characterized in that, in step S1, described based on astronomical positioning stellar database, generate all-sky area theoretical star map and The second index data used to express the angular distance information between stars included in the theoretical star map of the whole sky area refers to, 按照给定星等门限，选择全天区N2颗恒星星象，定义成第二候选恒星，结合第二候选恒星的赤经和赤纬，计算得到任意两颗第二候选恒星之间的角距，按照给定角距门限，任选三颗第二候选恒星组成三角形星图，生成全天区理论星图，并按照每个三角形的角距大小进行排序，生成相应的索引数据。According to the given magnitude threshold, select N 2 star images in the whole sky area, define them as the second candidate stars, and combine the right ascension and declination of the second candidate stars to calculate the angular distance between any two second candidate stars. , according to the given angular distance threshold, select three second candidate stars to form a triangular star map, generate a theoretical star map of the whole sky area, and sort according to the angular distance of each triangle to generate the corresponding index data. 5.根据权利要求4所述的基于指向自动测定的空间碎片实时天文定位和测光方法，其特征在于，步骤S1中，采用下式计算任意两颗第二候选恒星之间的角距：5. The real-time astronomical positioning and photometric method for space debris based on automatic pointing determination according to claim 4, characterized in that, in step S1, the following formula is used to calculate the angular distance between any two second candidate stars:
Figure FDA0002864364240000021
Figure FDA0002864364240000021
 其中，(αu,δu)是第u颗第二候选恒星的赤经和赤纬，(αv,δv)是第v颗第二候选恒星的赤经和赤纬，
Figure FDA0002864364240000022
是第u颗和第v颗第二候选恒星之间的角距。where (α u ,δ u ) are the right ascension and declination of the u-th second candidate star, (α v ,δ v ) are the right ascension and declination of the v-th second candidate star,
Figure FDA0002864364240000022
is the angular distance between the uth and vth second candidate stars. 6.根据权利要求1所述的基于指向自动测定的空间碎片实时天文定位和测光方法，其特征在于，步骤S3中，所述按照预设的匹配规则，计算得到恒星实测星图中所包含的与全天区理论星图相匹配的若干个恒星星象信息包括以下步骤：6. The method for real-time astronomical positioning and photometry of space debris based on automatic pointing determination according to claim 1, wherein in step S3, according to a preset matching rule, the calculated stars included in the actual measured star map are obtained. The several stellar constellation information that matches the theoretical star map of the whole sky area includes the following steps: S31：根据全天区理论星图和第二索引数据，确定候选星图的上下界限，获取最大角距
Figure FDA0002864364240000023
最小角距
Figure FDA0002864364240000024
中间角距
Figure FDA0002864364240000025
S31: Determine the upper and lower limits of the candidate star map according to the theoretical star map of the whole sky area and the second index data, and obtain the maximum angular distance
Figure FDA0002864364240000023
Minimum angular distance
Figure FDA0002864364240000024
Intermediate angular distance
Figure FDA0002864364240000025
 S32：依次计算上下界限中任意三颗定标星i,j,k组成的三角形的角距，设计算得到的角距由大到小顺序为
Figure FDA0002864364240000026
根据下述匹配条件，将计算得到的角距
Figure FDA0002864364240000027
对应
Figure FDA0002864364240000028
Figure FDA0002864364240000029
进行匹配判断，直至匹配成功N3颗恒星：S32: Calculate the angular distance of the triangle formed by any three calibration stars i, j, and k in the upper and lower limits in turn, and the calculated angular distance is in descending order of
Figure FDA0002864364240000026
According to the following matching conditions, the calculated angular distance
Figure FDA0002864364240000027
correspond
Figure FDA0002864364240000028
Figure FDA0002864364240000029
Make a matching judgment until the matching N 3 stars are successful: 第j颗定标星和第k颗定标星之间满足下式：The following formula is satisfied between the jth calibration star and the kth calibration star:
Figure FDA00028643642400000210
Figure FDA00028643642400000210
 任意三颗i,j,k定标星之间满足下式：The following formula is satisfied between any three i, j, k calibration stars:
Figure FDA0002864364240000031
Figure FDA0002864364240000031
 其中，ε1和ε2均为预设的角距门限；Among them, ε 1 and ε 2 are both preset angular distance thresholds; 7.根据权利要求1所述的基于指向自动测定的空间碎片实时天文定位和测光方法，其特征在于，步骤S4中，所述以匹配成功的若干个恒星星象信息为基础，计算得到中心指向偏差、像面旋转角的过程包括以下步骤：7. The real-time astronomical positioning and photometric method of space debris based on the automatic determination of pointing according to claim 1, is characterized in that, in step S4, described based on the information of several stars that have been matched successfully, calculate the center pointing The process of deviation and image plane rotation angle includes the following steps: 设匹配成功的N3颗恒星在图像上的二维平面坐标为(xi,yi)，i＝1,2,…N3，对应的二维平面坐标理论值为(Xi,Yi)，i＝1,2,…N3；Let the two-dimensional plane coordinates of the N 3 stars successfully matched on the image be (x i , y i ), i=1,2,...N 3 , and the corresponding theoretical two-dimensional plane coordinates are (X i ,Y i ) ), i=1,2,...N 3 ; 利用下式，采用最小二乘方法，计算出系数a,b,c,d,e,f，从而得到中心指向偏差及像面旋转角：Using the following formula, the least squares method is used to calculate the coefficients a, b, c, d, e, f, so as to obtain the center pointing deviation and the rotation angle of the image plane:
Figure FDA0002864364240000032
Figure FDA0002864364240000032
 8.根据权利要求1所述的基于指向自动测定的空间碎片实时天文定位和测光方法，其特征在于，步骤S4中，所述底片常数模型的获取过程包括以下步骤：8. The real-time astronomical positioning and photometric method for space debris based on automatic pointing determination according to claim 1, wherein in step S4, the acquisition process of the film constant model comprises the following steps: 结合天文定位恒星星库和第一索引数据，根据图像对应的拍摄信息和全天区星图指向测定结果(αp,δp)，检索出视场中满足给定星等门限的所有恒星的相关信息，所述满足给定星等门限的恒星的相关信息包括其所对应的二维平面坐标理论值(X,Y)、赤经和赤纬理论值(αs,δs)、理想坐标理论值(ξs,ζs)、理论星等M，按照理论星等由小到大的顺序对检索出的恒星进行排序；其中，所述理想坐标理论值(ξs,ζs)满足以下公式：Combined with the astronomical positioning star database and the first index data, according to the shooting information corresponding to the image and the measurement results of the star map pointing in the whole sky (α p , δ p ), retrieve all the stars in the field of view that meet the given magnitude threshold. Relevant information, the relevant information of the stars meeting the given magnitude threshold includes the corresponding theoretical values of two-dimensional plane coordinates (X, Y), the theoretical values of right ascension and declination (α s , δ s ), ideal coordinates Theoretical values (ξ s , ζ s ) and theoretical magnitudes M, sort the retrieved stars according to the order of theoretical magnitudes from small to large; wherein, the theoretical ideal coordinate values (ξ s , ζ s ) satisfy the following formula:
Figure FDA0002864364240000033
Figure FDA0002864364240000033
 其中，所述图像对应的拍摄信息包括图像的拍摄时间、指向信息、测站经纬度、测站海拔高度、测站温度、测站湿度、大气压强、给定视场大小；Wherein, the shooting information corresponding to the image includes the shooting time of the image, pointing information, the longitude and latitude of the measuring station, the altitude of the measuring station, the temperature of the measuring station, the humidity of the measuring station, the atmospheric pressure, and the size of the given field of view; 根据图像对应视场大小，结合匹配成功的N3颗恒星在图像上的二维平面坐标(xi,yi)，及理想坐标
Figure FDA0002864364240000034
进行常数模型计算，根据恒星的定位精度，自动优选底片常数模型，并且自动存储优选出的底片常数模型。According to the size of the corresponding field of view of the image, combine the two-dimensional plane coordinates (x i , y i ) of the successfully matched N 3 stars on the image, and the ideal coordinates
Figure FDA0002864364240000034
The constant model calculation is performed, and the film constant model is automatically selected according to the positioning accuracy of the star, and the selected film constant model is automatically stored. 9.根据权利要求8所述的基于指向自动测定的空间碎片实时天文定位和测光方法，其特征在于，所述进行常数模型计算包括，9. The real-time astronomical positioning and photometric method for space debris based on automatic pointing determination according to claim 8, wherein the performing constant model calculation comprises: 结合匹配成功的定标星数量，分别选用六常数模型、十二常数模型、十四常数模型进行常数模型计算，其中：Combined with the number of successfully matched calibration stars, the six-constant model, the twelve-constant model, and the fourteen-constant model are respectively selected for constant model calculation, among which: 所述六常数模型对应至少3个以上的定标星：The six-constant model corresponds to at least three or more calibration stars:
Figure FDA0002864364240000041
Figure FDA0002864364240000041
 所述十二常数模型对应至少6个以上的定标星：The twelve constant models correspond to at least 6 or more calibration stars:
Figure FDA0002864364240000042
Figure FDA0002864364240000042
 所述十四常数模型对应至少7个以上的定标星：The fourteen constant model corresponds to at least 7 or more calibration stars:
Figure FDA0002864364240000043
Figure FDA0002864364240000043
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