A target search method for a small-field-of-view photoelectric telescope

Abstract

The present invention relates to the field of telescope control technology, and specifically provides a method for target search in a small-field-of-view optoelectronic telescope. The method calculates actual azimuth guidance data and actual pitch guidance data by calculating original azimuth guidance data, original elevation guidance data, an azimuth guidance correction value, an elevation guidance correction value, a current azimuth reference offset, and a current elevation reference offset, thereby performing target search and guidance for the small-field-of-view optoelectronic telescope. The current azimuth reference offset and the current elevation reference offset can be selected based on historical data according to the actual situation of the guidance source. The method can formulate a search path based on search requirements, has an unlimited search range, and is highly applicable and flexible. Furthermore, the same guidance source can utilize existing reference offset data in a database, shortening target search time and significantly improving target search efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of telescope control, and in particular provides a target searching method for a small-field-of-view photoelectric telescope. Background Art

[0002] To produce a larger image of a target and reveal richer details, the imaging system of an electro-optical telescope typically has a very small field of view. This small field of view makes it difficult for a single imaging system to capture and image an unknown target. Typical telescopes are equipped with a capture system with a larger field of view to introduce the target into the imaging system and perform related observations and scientific experiments. However, for reasons such as reducing R&D costs and reducing the weight and size of the telescope, some telescopes are designed without a capture system.

[0003] When real-time guidance of a target with a known trajectory is performed on a small-field telescope, the target may not be imaged within the telescope's field of view due to the potential for a certain field of view deviation between the guided trajectory and the target's actual trajectory. Due to the small field of view of the target telescope, target search is relatively difficult, making it difficult to conduct relevant observation experiments smoothly.

[0004] In the following situations, a small field of view telescope needs to use the target search function to find the target:

[0005] (1) Using stars for zero correction: After the first installation of the photoelectric telescope or after the site change, zero correction is required for normal use. The common method is to calculate the real-time azimuth and elevation of the star, adjust the star to the center of the field of view by superimposing the correction value, and use this correction value as the zero correction value. However, for telescopes with a small field of view, the star is unlikely to appear in the field of view before zero correction. The operator needs to manually adjust the correction value multiple times, which not only wastes a lot of time but is also prone to errors, making the correction work difficult to carry out smoothly.

[0006] (2) There is a deviation between the guided trajectory and the actual trajectory: During external guidance, if the guiding source device and the guided device have different locations or different working principles, the target trajectory parsed by the guided device may deviate. When using two rows of orbital elements to guide a satellite, if the elements have not been updated for a long time or the satellite changes its orbit, the guided trajectory may also deviate. In the above situation, a small field of view telescope needs to search for the target around its field of view based on the existing trajectory before it can observe.

[0007] Currently, the most common search method involves the operator continuously adjusting correction values ​​to bring the target into view. However, when the target isn't in view, the operator often can't determine the correct direction or amount. Furthermore, it's difficult for the operator to make corrections consistently, resulting in a lengthy process to bring the target into view, and potentially even failing to complete the task within the available observation time.

[0008] The Chinese patent publication number is CN111288968A, published on June 16, 2020, and the patent name is "An automatic measurement system for space targets based on active search strategy". The above patent application only states that its method is to superimpose fixed offsets in adjacent directions to achieve The step search method for adjacent fields of view does not provide a method for continuing to expand to 、 Even larger areas. In other words, The offsets of adjacent areas of small size can be calculated manually and solidified into the software code, but it is impossible to manually calculate all the offsets of larger adjacent areas. More specific rules or formulas are needed to automate it using software code. Summary of the Invention

[0009] To solve the above problems, the present invention provides a target search method for an optoelectronic telescope with a small field of view. The method calculates actual guidance data of the optoelectronic telescope with a small field of view according to a predetermined trajectory, guides the optoelectronic telescope to search for the target along the trajectory, and records the corresponding data for secondary use, thereby improving the target search efficiency and enhancing the flexibility and applicability of the search system.

[0010] The present invention provides a method for searching a target with a small-field-of-view optoelectronic telescope, comprising:

[0011] S1: Obtain the coordinates of the target position in real time through the guidance source as the original azimuth guidance data of the telescope and raw pitch guidance data ;

[0012] S2: Calculate the azimuth component of the telescope's field of view based on the telescope's own optical parameters and pitch component ;

[0013] S3: Based on the azimuth component and pitch component Calculate azimuth guidance correction and pitch guidance correction ;

[0014] S4: Calculate the current azimuth reference offset of the telescope and the current pitch reference offset ;

[0015] S5: Based on original position guidance data , original pitch guidance data , azimuth guidance correction , pitch guidance correction , Current azimuth reference offset and the current pitch reference offset Calculate actual bearing guidance data and actual pitch guidance data ;

[0016] S6: Guidance data based on actual position and actual pitch guidance data , guide the telescope to move until the target is found, and calculate the target and the corresponding original azimuth guidance data and raw pitch guidance data The distance between them is used as the next azimuth reference offset and pitch reference offset .

[0017] Preferably, the azimuth and elevation of the telescope pointing are shifted and searched only one field of view at a time.

[0018] Preferably, the azimuth guidance correction amount and pitch guidance correction The calculation method is:

[0019] ;

[0020] ;

[0021] in, Indicates the direction and number of azimuth deviations of the telescope. Indicates the direction and number of elevation deviations of the telescope's pointing direction.

[0022] Preferably, the direction and number of azimuth deviations of the telescope pointing The direction and number of pitch deviations from the telescope's pointing direction The rules that are satisfied are:

[0023] ;

[0024] in, The azimuth and elevation of the telescope are both moved up one field of view and to the right. Field of view, move downward Field of view, move left Field of view, move up Field of view, Indicates the number of circles the telescope searches for the target. Indicates upward movement. Indicates moving to the right. Indicates downward movement. Indicates moving to the left.

[0025] Preferably, the current azimuth reference offset and the current pitch reference offset The calculation method is:

[0026] Determine whether the telescope system parameters have changed before this target search:

[0027] If the telescope system parameters change before this target search, then ;

[0028] If the telescope system parameters have not changed before the target search, determine whether the current telescope guidance source has searched for the target before:

[0029] If the current telescope guidance source has not searched for the target, then ;

[0030] If the current telescope guidance source has searched for the target before, the azimuth reference offset calculated when the target was searched before is used. and pitch reference offset As the current orientation reference offset and the current pitch reference offset .

[0031] Preferably, actual position guidance data and actual pitch guidance data The calculation method is:

[0032] ;

[0033] .

[0034] Preferably, the method for determining whether the telescope system parameters have changed is: if the telescope observation station site changes, the telescope is re-zeroed, or the telescope is re-pointing error calibrated, then the telescope system parameters are considered to have changed.

[0035] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0036] When performing a target search, the present invention can predetermine a search trajectory according to the search method desired by the user, thereby realizing a specific trajectory search with high flexibility and strong applicability. When performing a target search, the reference offset is recorded as historical data in a corresponding guidance source database. When the same guidance source is used to perform a target search task again, the historical data can be directly used without the need to calculate the reference offset again, thereby adjusting the target search starting point, shortening the calculation time, speeding up the target search process, and greatly improving the target search efficiency. At the same time, the method of the embodiment of the present invention can perform a target search within an unlimited range according to a predetermined rule, and can be stopped at any time under special circumstances, thereby having strong practicality and high flexibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a flow chart of a target search method provided according to an embodiment of the present invention;

[0038] Figure 2 is a schematic diagram of a spiral path when searching for a target according to an embodiment of the present invention;

[0039] Figure 3 is a flowchart of calculating a reference offset according to an embodiment of the present invention;

[0040] Figure 4 It is a schematic diagram of a path for a guidance source to search for a target non-first time according to an embodiment of the present invention. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation to the present invention. Similar elements in different embodiments use associated similar element numbers. In the following embodiments, many detailed descriptions are intended to enable the present invention to be better understood. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, or methods. In some cases, some operations related to the present invention are not shown or described in the specification. This is to avoid the core part of the present invention being overwhelmed by too much description. For those skilled in the art, it is not necessary to describe these related operations in detail. They can fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0042] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other to form various implementation methods. At the same time, the steps or actions in the method description can also be interchanged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various orders in the description and the drawings are only for the purpose of clearly describing a certain embodiment and are not intended to be a required order, unless otherwise specified that a certain order must be followed.

[0043] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0044] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art can understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0045] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0046] like Figure 1 As shown, the embodiment of the present invention provides a method for searching targets with a small field of view optoelectronic telescope, which is specifically as follows:

[0047] When observing and tracking a target, a small-field-of-view electro-optical telescope (hereinafter referred to as a telescope) requires the cooperation of a guidance source. The guidance source acquires the target's coordinates in real time and transmits these coordinates as guidance data to the telescope. The telescope points to these coordinates to observe the target. This process typically involves a coordinate system conversion to obtain guidance data for the telescope.

[0048] Since there are precision errors in the guidance source, telescope and other systems, even if the guidance data obtained by the guidance source is used to guide the telescope, there may be situations where the target cannot be included in the field of view. Target search is required to successfully observe the target.

[0049] S1: The target position coordinates acquired in real time by the guidance source include the azimuth coordinates and the pitch coordinates of the target. In the embodiment of the present invention, the target position coordinates acquired in real time by the guidance source are referred to as original guidance data. The azimuth coordinates and the pitch coordinates of the original guidance data are respectively referred to as original azimuth guidance data. and raw pitch guidance data , original orientation guidance data and raw pitch guidance data It is the initial guidance data without correction. If the original azimuth guidance data is used directly and raw pitch guidance data When guiding the telescope, there may be a situation where there is no target in the field of view, so the original azimuth guidance data needs to be and raw pitch guidance data After processing, the telescope is guided to search for the target.

[0050] S2: Since the guidance data consists of azimuth and elevation values, the embodiment of the present invention decomposes the relevant data values ​​into azimuth and elevation values ​​for presentation. First, the observation field of the telescope is divided into azimuth components. and pitch component , the azimuth component can be calculated based on the optical parameters of the telescope itself and pitch component , this calculation process is existing technology.

[0051] The optical parameters of the photoelectric telescope include focal length, field of view, lens or mirror size, etc. It refers to the angular range that the telescope can observe on the horizontal plane (i.e., the equatorial projection of the celestial sphere), which is usually related to the telescope's rotation or horizontal scanning capability and determines the area of ​​the sky that the telescope can cover in the east-west direction. It refers to the angular range that the telescope can observe in the vertical direction (that is, the angle relative to the horizon), which determines the altitude range of the sky area that the telescope can observe, from the horizon to a certain highest point. and pitch component The calculation belongs to the existing technology.

[0052] S3: Under normal circumstances, the target's motion trajectory is an arc. Therefore, when the telescope rotates and tracks the target according to the guidance data provided by the guidance source, the trajectory it points to is also an arc. In this embodiment of the present invention, the original azimuth guidance data and raw pitch guidance data That is, the point on the arc that the telescope points to when tracking the target. When searching for a target through a telescope, a certain route rule is usually selected for searching. The embodiment of the present invention uses a spiral rule for searching. When the telescope moves in an arc, after searching in combination with the spiral rule, the pointing trajectory formed is as follows Figure 2 The tracking rules of the embodiment of the present invention are as follows:

[0053] The azimuth deviation direction and number of telescope pointing are expressed as , the pitch deviation direction and number of telescope pointing are expressed as , and All are integers, and their initial values ​​are all 0. and pitch component Calculate the guidance correction amount. In this embodiment of the present invention, the guidance correction amount is divided into the azimuth guidance correction amount and pitch guidance correction , calculate the azimuth guidance correction and pitch guidance correction :

[0054] ;

[0055] ;

[0056] When calculating, and They can be positive, negative or 0. The sign indicates the direction and the absolute value indicates the number of times. constant, Increase by 1 when the telescope points to the right. Increase by 1, remains unchanged, when the telescope is pointed downward, constant, Decrease by 1, and when the telescope moves to the left, Decrease by 1, constant.

[0057] The direction and number of times the telescope's pointing direction deviates The direction and number of pitch deviations from the telescope's pointing direction The following spiral rules are also satisfied:

[0058] ;

[0059] in, The azimuth and elevation of the telescope are both moved up one field of view and to the right. Field of view, move downward Field of view, move left Field of view, move up Field of view, Indicates the number of circles the telescope searches for the target. Indicates upward movement. Indicates moving to the right. Indicates downward movement. Indicates moving to the left.

[0060] like Figure 2 As shown, when searching, the data is guided by the original direction and raw pitch guidance data As the central location, Figure 2 Start the spiral search from point "C" in the figure. In the first circle search, start from point "C" and search one field of view in the positive direction of pitch, that is, search one field of view upward. constant, , then search one field of view in the positive direction of the azimuth, that is, search one field of view to the right, constant, , then search two fields of view in the negative direction of pitch, that is, search two fields of view downward, each time searching a field of view, constant, , then search two fields of view in the negative direction of the azimuth, that is, search two fields of view to the left, each time a field of view is searched, constant, . And so on for the second, third, and so on. The relationship between the number of circles, the corresponding directions and the number of fields of view is shown in Table 1. It should be noted that no matter which circle the search is, each time the telescope is pointed, it only moves one field of view in the regular direction, that is, only one field of view is searched each time. and The calculation of the azimuth guidance correction value corresponding to the field of view is obtained and pitch guidance correction .

[0061] It should be noted that, in the above content, 、 、 ,and In the middle, before the equal sign or Indicates the current step or , after the equal sign or Indicates the previous step corresponding to or , that is, the current step corresponds to or It corresponds to the previous step or Based on the addition or subtraction operation.

[0062] Table 1

[0063]

[0064] When searching for targets in a spiral pattern, the telescope only moves one field of view at a time, and after moving to the field of view, it searches for targets in the field of view and determines whether there are targets in the field of view. After the search is completed, if there are no targets and the search does not stop, it moves to the next field of view in a spiral pattern. Specifically, when the telescope moves and searches in a spiral pattern, the area searched in the first circle contains eight fields of view. Each time it reaches a field of view, it is necessary to search for targets and determine whether there are targets and whether to continue searching. Therefore, the first circle of search actually needs to be performed eight times. Similarly, the second circle requires the telescope to move sixteen times, and perform sixteen target searches and corresponding judgments. Therefore, the movement in the spiral pattern or The field of view is not a direct leap or field of view, but requires or Moves are required to complete the move or Fields of view, each field of view performs target search and judgment, so the corresponding number of searches and judgments is also or Second-rate.

[0065] S4: After selecting the search field according to the above rules, the telescope needs to be guided to the field to search for the target. Therefore, the actual guidance data corresponding to the field needs to be calculated, that is, the actual azimuth guidance data and actual pitch guidance data To guide the telescope.

[0066] like Figure 3 As shown, calculate the azimuth guidance correction and pitch guidance correction The current reference offset of the telescope needs to be calculated. The current reference offset is divided into the current azimuth reference offset and the current pitch reference offset . Azimuth reference offset and pitch reference offset It can be understood as the guidance error of the guidance source, which needs to be corrected when actually guiding the telescope. When the guidance telescope is rotated, if the guidance source does not change, it is considered that the azimuth reference offset and pitch reference offset It also remains unchanged.

[0067] Current orientation reference offset and the current pitch reference offset The values ​​are as follows:

[0068] Determine whether the telescope system parameters have changed before the target search. If the telescope system parameters have changed before the target search, then If the telescope system parameters have not changed before the target search, then determine whether the current telescope guidance source has searched the target before. If the current telescope guidance source has not searched the target before, then If the current telescope guidance source has searched for the target before, the azimuth reference offset calculated when the target was searched before will be used. and pitch reference offset As the current orientation reference offset and the current pitch reference offset .

[0069] When judging whether the telescope's system parameters have changed, if the telescope has the following conditions, it is considered that the telescope's system parameters have changed:

[0070] If the location of the observation station where the telescope is located changes, it means that its longitude, latitude or altitude has changed, and the telescope system parameters are considered to have changed; if the telescope is repaired, re-adjusted, etc., and its zero position is re-corrected, its zero position correction value changes, and the telescope system parameters are considered to have changed; if the telescope is re-calibrated using stars or other methods for pointing error, the telescope system parameters are also considered to have changed. In all the above cases, the current azimuth reference offset and the current pitch reference offset The average value is 0.

[0071] In particular, the guidance deviation of the same guidance source in different time periods is very small, but the guidance deviation of different guidance sources cannot be ignored. When guiding the telescope, there is also the situation of changing the guidance source, and the azimuth reference offset and pitch reference offset These are the guidance source's own parameters. Therefore, changing the guidance source will also affect these two data. After changing the guidance source, you also need to use the azimuth reference offset obtained by the last calculation recorded in the changed guidance source database. and pitch reference offset As the current azimuth reference offset and the current pitch reference offset Similarly, regardless of whether a guidance source change occurs, if there is no historical azimuth datum offset in the guidance source database being used and pitch reference offset , then the current azimuth reference offset and the current pitch reference offset The average value is 0.

[0072] The method to determine whether the boot source has changed is as follows:

[0073] When the guidance source is connected via a serial port, if the serial port number received by the telescope receiver is the same, it is considered to be the same guidance source and the guidance source has not changed. When the guidance source is connected via a network communication, if the guidance source IP address is the same, it is considered to be the same guidance source and the guidance source has not changed. When the guidance source is local real-time guidance, if the number of track elements in the two rows is the same, it is considered to be the same guidance source and the guidance source has not changed.

[0074] S5: Get original orientation guidance data , original pitch guidance data , azimuth guidance correction , pitch guidance correction , Current azimuth reference offset and the current pitch reference offset Then, the actual guidance data for guiding the telescope is calculated based on these data, that is, the actual azimuth guidance data and actual pitch guidance data :

[0075] ;

[0076] .

[0077] Actual bearing guidance data and actual pitch guidance data It is the guidance data that is ultimately used to guide the telescope to rotate to search the field of view, through the actual azimuth guidance data and actual pitch guidance data According to the spiral law in S3, the telescope is guided to search each field of view one by one in a specific direction.

[0078] S6: When searching each field of view, if the target is not found, continue searching according to the predetermined rule. The predetermined rule in the embodiment of the present invention is the spiral rule. If the target is found in a certain field of view, the corresponding current azimuth reference offset is recorded. and the current pitch reference offset Save to the guidance source database as the next azimuth reference offset and pitch reference offset When the guidance source guides the target tracking task again, the record can be used to calculate the actual direction guidance data and actual pitch guidance data .

[0079] When the target is found, the current azimuth reference offset and the current pitch reference offset The distance between the target and the starting point when searching for the target, that is, the original bearing guidance data and raw pitch guidance data The distance between the corresponding coordinate point and the target coordinate point.

[0080] like Figure 4 As shown, through this recording method, when the same guidance source is not searching for the target for the first time, the azimuth reference offset that has been recorded can be fully utilized. and pitch reference offset First adjust the center point. The adjusted center point is the point after the center position C is corrected, that is, Figure 4 The search starting point in the image is set as the adjusted center point, and then the target search is started from the adjusted center point. This can help to find the target faster, shorten the search time, and improve the efficiency of finding the target.

[0081] During the target search process, there are also cases where the user needs to stop the search midway due to other reasons. The stopped node may be any node in the search process. In this case, when the user needs to stop the search midway, the stopped position may not be the target position. Therefore, in this special stop, the azimuth reference offset corresponding to the stopped position is not recorded. and pitch reference offset .

[0082] Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0083] The above specific embodiments of the present invention do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A method for searching targets with a small field-of-view optoelectronic telescope, characterized in that: include: S1: Obtain the coordinates of the target position in real time through the guidance source as the original azimuth guidance data of the telescope and raw pitch guidance data ; S2: Calculate the azimuth component of the telescope's field of view based on the telescope's own optical parameters and pitch component ; S3: According to the orientation component and pitch component Calculate azimuth guidance correction and pitch guidance correction ; S4: Calculate the current azimuth reference offset of the telescope and the current pitch reference offset ; S5: Guiding data based on the original position , original pitch guidance data , azimuth guidance correction , pitch guidance correction , Current azimuth reference offset and the current pitch reference offset Calculate actual bearing guidance data and actual pitch guidance data ; S6: Guiding data based on the actual position and actual pitch guidance data , guide the telescope to move until the target is found, and calculate the target and the corresponding original azimuth guidance data and raw pitch guidance data The distance between them is used as the next azimuth reference offset and pitch reference offset .

2. The method for searching targets with a small field of view optoelectronic telescope according to claim 1, wherein: The azimuth and elevation of the telescope pointing are shifted and searched only one field of view at a time.

3. The method for searching targets with a small field of view optoelectronic telescope according to claim 1, wherein: The azimuth guidance correction amount and pitch guidance correction The calculation method is: ； ； in, Indicates the direction and number of azimuth deviations of the telescope. Indicates the direction and number of elevation deviations of the telescope's pointing direction.

4. The method for searching a target with a small field of view optoelectronic telescope according to claim 3, wherein: The direction and number of times the telescope's pointing direction deviates The direction and number of pitch deviations from the telescope's pointing direction The rules that are satisfied are: ； in, The azimuth and elevation of the telescope are both moved up one field of view and to the right. Field of view, move downward Field of view, move left Field of view, move up Field of view, Indicates the number of circles the telescope searches for the target. Indicates upward movement. Indicates moving to the right. Indicates downward movement. Indicates movement to the left.

5. The method for searching targets with a small field-of-view optoelectronic telescope according to claim 1, wherein: The current azimuth reference offset and the current pitch reference offset The calculation method is: Determine whether the telescope system parameters have changed before this target search: If the telescope system parameters change before this target search, then ; If the telescope system parameters have not changed before the target search, determine whether the current telescope guidance source has searched for the target before: If the current telescope guidance source has not searched for the target, then ; If the current telescope guidance source has searched for the target before, the azimuth reference offset calculated when the target was searched before is used. and pitch reference offset As the current orientation reference offset and the current pitch reference offset .

6. The method for searching targets with a small field-of-view optoelectronic telescope according to claim 1, wherein: The actual position guidance data and actual pitch guidance data The calculation method is: ； 。 7. The method for searching targets with a small field-of-view optoelectronic telescope according to claim 5, wherein: The method for determining whether the telescope system parameters have changed is: if the telescope observation station site changes, the telescope is re-zeroed, or the telescope is re-calibrated for pointing error, then the telescope system parameters are considered to have changed.

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