Agile satellite on-satellite autonomous adaptive strip segmentation method

Abstract

The invention discloses an on-satellite autonomous adaptive strip segmentation method for an agile satellite, and the method comprises the steps: comparing the efficiency of active and passive push-scan and segmentation for a given polygonal region target on the basis of obtaining the scanning breadth of the satellite based on a load field angle and an orbit height, and selecting an optimal scanning direction, thereby flexibly adjusting the push-scan and segmentation modes and directions. Meanwhile, the strips are cut based on geometric figures, and the output efficiency and quality of agile satellite task planning are comprehensively improved from multiple links. According to the on-satellite autonomous task planning strip cutting method provided by the invention, the detection efficiency of an agile imaging satellite on a ground area target can be remarkably improved, the practical problem of satellite in-orbit application is solved, the development of a remote sensing satellite towards the intelligent autonomous direction is supported, and the method has practicability.

Description

Technical Field

[0001] The present invention relates to an on - satellite autonomous adaptive strip segmentation method for agile satellites, belonging to the field of spacecraft autonomous mission planning. Background Technique

[0002] A remote sensing satellite refers to an artificial earth satellite carrying payloads such as high - resolution cameras, infrared cameras, wide - swath cameras, real - time processing units, etc., which conducts space - based observations on ground or air targets, and has multiple imaging modes such as side - looking imaging (two - axis), regional multi - strip mosaicking imaging, three - view stereoscopic imaging, multi - angle imaging, non - along - track active push - broom imaging, etc., as well as the ability of on - orbit real - time image processing.

[0003] For an agile remote sensing satellite equipped with a high - resolution optical payload, when the satellite images, it images in a push - broom mode. As Figure 2 shown, corresponding to a strip observation area on the earth's surface, the length of the area is affected by the imaging time, and the width of the area is called the swath width, which is affected by the payload field of view angle and the orbital altitude. The existing strip segmentation methods for regional targets of agile satellites have low flexibility, and the strip segmentation direction and the push - broom direction are single and fixed (generally can only scan along the sub - satellite track direction), which is not conducive to improving the satellite maneuvering efficiency and the imaging task completion efficiency. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: aiming at the problem that the existing strip segmentation methods for regional targets of agile satellites have low flexibility, the strip segmentation direction and the push - broom direction are single and fixed, which is not conducive to improving the satellite maneuvering efficiency and the imaging task completion efficiency, an on - satellite autonomous adaptive strip segmentation method for agile satellites is proposed, which comprehensively improves the efficiency and quality of the agile satellite detection task from multiple aspects.

[0005] The object of the present invention is achieved through the following technical solutions:

[0006] An on - satellite autonomous adaptive strip segmentation method for agile satellites, on the basis of obtaining the satellite scan swath width based on the payload field of view angle and the orbital altitude, compares the efficiency of active, passive push - broom and segmentation for a given polygonal regional target, selects the optimal scan direction, so as to flexibly adjust the push - broom and segmentation methods and directions. At the same time, the strip is cropped based on geometric figures, comprehensively improving the output efficiency and quality of the agile satellite mission planning from multiple aspects.

[0007] In the first aspect, the present invention provides an on - satellite autonomous adaptive strip segmentation method for agile satellites, including:

[0008] S1. Determine the search quadrilateral area, as well as the imaging satellite type and payload parameters;

[0009] S2. Obtain the sub - satellite track direction according to the satellite orbit elements;

[0010] S3. Obtain the coordinates of the geometric center point of the quadrilateral area based on the coordinates of the 4 vertex points of the quadrilateral area;

[0011] S4. Obtain the scanning direction in which the agile satellite scans along the 4 sides of the quadrilateral area;

[0012] S5. Based on the to-be-determined scanning direction, respectively determine the maximum quadrilateral envelope for scanning the quadrilateral area, and determine the number of scanning strips according to the scanning width;

[0013] S6. Perform adaptive adjustment and clipping on the scanning strips according to the line segments formed by the 4 sides of the quadrilateral area;

[0014] S7. Respectively determine the total scanning length of the strips according to the to-be-determined scanning direction, select the optimal final area scanning direction, and then determine whether to use active scanning or passive scanning. If it is active scanning, go to step S8; if it is passive scanning, go to step S9;

[0015] S8. Directly output the strip clipping result;

[0016] S9. Fine-tune the strip clipping result according to the sub-satellite point width of the satellite scanning points and then output.

[0017] In a second aspect, the present invention provides a computer program product stored on a non-transitory computer-readable medium, and the computer program product includes program codes for implementing the method described in the first aspect.

[0018] In a third aspect, the present invention provides an electronic device, including:

[0019] A processor; and

[0020] A memory for storing computer program instructions;

[0021] Wherein when the computer program instructions are loaded and run by the processor, the processor executes the method described in the first aspect.

[0022] The present invention has the following beneficial effects compared with the prior art:

[0023] (1) The active and passive strip segmentation and push-broom method based on the payload perspective of the present invention makes the imaging task more adaptable to the payload, and realizes the synchronous improvement of the segmentation efficiency and imaging quality.

[0024] (2) The method of the present invention has been verified in orbit by multiple satellites, provides task planning for agile earth imaging with multiple payloads for users, and the imaging results meet the user's requirements.

[0025] (3) The method of the present invention has strong autonomy and practicability, has been verified in orbit by multiple satellites, and is suitable for application in agile imaging satellites.

[0026] (4) The method of the present invention is applicable to mission planning in the process of remote sensing satellite earth observation and can be extended to other satellite platforms. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a flowchart of the method of the present invention.

[0028] Figure 2 It is a schematic diagram of imaging in the pushbroom mode during satellite imaging.

[0029] Figure 3 It is a schematic diagram of passive scanning.

[0030] Figure 4 It is a schematic diagram of active scanning.

[0031] Figure 5 It is an example of cutting strip description elements / coordinate definition.

[0032] Figure 6 It is an example of strip cropping method.

[0033] Figure 7 It is an example of satellite scan width, orbital altitude and field of view angle. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] To make the objectives, technical solutions and advantages of the present invention clearer, the following will further describe the embodiments of the present invention in detail with reference to the accompanying drawings.

[0035] Regional target: The regional target processed in the present invention is a quadrilateral, that is, it includes 4 vertices and 4 boundaries, which is used as the initial input of the method of the present invention.

[0036] Satellite scan width: The regional width during satellite earth imaging, which is related to the field of view angle of the satellite and the satellite operating orbital altitude, as Figure 7 shown.

[0037] Along-track scan direction: The scan direction formed by the satellite along the sub-satellite point track direction, which belongs to passive scanning, as Figure 3 shown.

[0038] Along-edge scan direction: The scan direction formed by the satellite along the 4 sides of the quadrilateral, which belongs to active scanning, as Figure 4 shown.

[0039] Scan strip: The strip-shaped scan area formed by the satellite for regional detection, which is a quadrilateral strip, as Figure 3 、 Figure 4 shown. The cut strip can be directly output to the satellite for the satellite to directly execute, which is the final output of the present invention.

[0040] The method of the present invention will be described in detail below in conjunction with the accompanying drawings.

[0041] An on-board autonomous adaptive strip segmentation method for agile satellites, as Figure 1 shown, includes the following steps:

[0042] ① Establish the search task; determine the basic parameters of the search quadrilateral area (including the coordinates of the four vertices), as well as the imaging satellite category and payload parameters (such as the field of view angle, imaging swath width, etc.).

[0043] This step is the original input of the method of the present invention.

[0044] The quadrilateral area contains the coordinates of 4 vertices in the geocentric coordinate system or the geodetic latitude, longitude and altitude in the Earth coordinate system.

[0045] The category of the satellite is the type of imaging satellite, including infrared imaging satellite, visible light imaging satellite, hyperspectral satellite or microwave radar satellite, etc.

[0046] The satellite payload parameters are related to the type of imaging satellite, and generally include the field of view angle of imaging, and the imaging swath width (related to the satellite field of view angle and orbital altitude).

[0047] ② Obtain the sub-satellite point track direction according to the satellite orbital elements.

[0048] Based on the currently locally stored orbital elements, or the GPS / Beidou orbital data received by the satellite, extrapolate to obtain the orbital elements of the satellite at the target detection time of the quadrilateral area, and calculate the sub-satellite point track direction of the satellite at the target detection time according to the argument of latitude u and the orbital inclination i, that is, the approximate nominal pushbroom direction theta_Scan0 of the satellite detection at this time.

[0049] ③ Obtain the coordinates of the geometric center point of the area according to the coordinates of the 4 vertices of the quadrilateral area.

[0050] Based on the coordinates of the 4 vertices of the quadrilateral area, calculate the coordinates of the center of the target area in the geocentric coordinate system and the geodetic latitude, longitude and altitude in the Earth coordinate system.

[0051] Obtain the coordinate transformation matrix from the Earth geocentric coordinate system to the local northeast celestial coordinate system of the center of the quadrilateral area according to the geocentric coordinate of the center point of the quadrilateral area.

[0052] ④ Obtain the scanning directions of the agile satellite scanning along the 4 sides of the quadrilateral area.

[0053] Sequentially write out the straight line equations of the 4 line segments of the quadrilateral area target, that is, calculate k and b in x = k*y + b. For each line segment, by calculating the position vector difference between two points, find the two vertices along the track direction, and according to the formula k_i = (xV_i - xV_j) / (yV_i - yV_j), obtain the line segment slope coefficient ki , and then the coefficient b is obtained i . Where [xV_i, yV_i] are the coordinates of vertex i of the quadrilateral region, and [xV_j, yV_j] are the coordinates of vertex j of the quadrilateral region, and vertex i is adjacent to vertex j.

[0054] The scanning direction theta_Scan of each line segment is obtained through the coefficient k i = atan2(k i ), i = 1, 2, … 4, k i is the line segment slope of the four sides of the quadrilateral region; the size of theta_Scan is adjusted by +pi or -pi i to adjust theta_Scan i to the range of [theta_Scan0 - 0.5*pi, theta_Scan0 + 0.5*pi).

[0055] ⑤ Based on 5 undetermined scanning directions (1 along-track + 4 along-edge), the maximum quadrilateral envelope of the quadrilateral region scanning is determined respectively, and the number of scanning strips is determined according to the scanning width.

[0056] According to the coordinates of the center (row center) of the quadrilateral region, the transformation matrix C_PE from the Earth-fixed coordinate system to the local north-east-down coordinate system of the center point of the quadrilateral region is obtained, and the scanning angle theta_Scan under 5 undetermined scanning directions (1 along-track + 4 along-edge) is obtained. A characteristic coordinate system of the quadrilateral region is constructed, with its origin at the centroid of the quadrilateral region, the X-axis is consistent with the satellite scanning direction, and the Z-axis points from the Earth center to the row center of the quadrilateral region. Thus, the transformation matrix from the Earth-fixed coordinate system to the characteristic coordinate system along the satellite scanning direction of the center point of the quadrilateral target region is C_VE = Rz(theta_Scan)*C_PE. Where, theta_Scan is the scanning angle theta_Scan of the satellite under 5 undetermined scanning directions (1 along-track + 4 along-edge) of the quadrilateral region, and Rz(theta_Scan) is the coordinate transformation matrix rotating around the Z-axis by theta_Scan.

[0057] According to the transformation matrix C_VE, the coordinate points of the 4 vertices r_s_E(i), i = 1, 2, …, 4 of the quadrilateral region in the target characteristic coordinate system are obtained, that is, 4 characteristic point vectors r_s_V(i) = C_VE*r_s_E(i), i = 1, 2, …, 4.

[0058] According to the characteristic point vector coordinates r_s_V(i) of the 4 vertices, their rectangular envelopes along 5 scanning directions (1 along-track + 4 along-edge) are obtained.

[0059] Max_Vy = max(r_s_V(2, :)); The maximum Vy among the characteristic point vector coordinates of the 4 vertices

[0060] Min_Vy = min(r_s_V(2, :)); The minimum Vy among the characteristic point vector coordinates of the 4 vertices

[0061] Max_Vx = max(r_s_V(1, :)); The maximum Vx among the characteristic point vector coordinates of the 4 vertices

[0062] Min_Vx = min(r_s_V(1, :)); The minimum Vx among the characteristic point vector coordinates of the 4 vertices

[0063] Thus, the width of the rectangular envelope is obtained as: W_Evp = Max_Vy - Min_Vy. The length of the envelope is Max_Vx - Min_Vx.

[0064] The calculation formula for the number of satellite scan strips is as follows: N_Strip = W_Evp / mW_Swath. Where W_Evp is the width envelope in the vertical scan direction, and mW_Swath is the swath width at the satellite's sub-satellite point.

[0065] For each strip, three-dimensional vectors YL_i (left), YM_i (middle), YR_i (right), XF_i (front), and XB_i (rear) are used to describe its position, as Figure 5 shown. Among them, YL_i, YM_i, and YR_i describe the width information of the strip, including the left, middle, and right position coordinates. XF_i and XB_i describe the length information of the strip. F represents the front position coordinate, and B represents the rear position coordinate.

[0066] The coordinate description of the first strip is as follows:

[0067] The left coordinate of the strip is: YL_(1) = Min_Vy; % left

[0068] The middle coordinate of the strip is: YM_(1) = YL_(1) + 0.5 * mW_Swath; % middle

[0069] The right coordinate of the strip is: YR_(1) = YL_(1) + mW_Swath; % right

[0070] The front coordinate of the strip is: XF_(1) = Max_Vx; % front

[0071] The rear coordinate of the strip is: XB_(1) = Min_Vx; % rear

[0072] The coordinate descriptions of the remaining N_Strip - 1 strips are as follows:

[0073] The coordinates of each strip (i) relative to the previous strip (i - 1) are:

[0074] The left coordinate of the strip is: YL_(i) = YL_(i - 1)+mW_Swath; % left

[0075] The middle coordinate of the strip is: YM_(i) = YL_(i)+0.5*mW_Swath; % middle

[0076] The right coordinate of the strip is: YR_(i) = YL_(i)+mW_Swath; % right

[0077] The front coordinate of the strip is: XF_(i) = XF_(1); % front

[0078] The back coordinate of the strip is: XB_(i) = XB_(1); % back

[0079] ⑥ Strip clipping. According to the line segments formed by the four sides of the quadrilateral region, the satellite scan strip is adaptively adjusted and clipped.

[0080] After initially obtaining each strip according to step ⑤, it is necessary to perform adaptive adjustment on each strip according to the positions of the four vertices of the rectangular region. The specific steps are as follows:

[0081] Judge the intersection points of the rectangular strip and each boundary line segment of the quadrilateral region, as Figure 6 shown. For each line segment, by the method of the straight-line equation (according to the formula k_i=(xV_i - xV_j) / (yV_i - yV_j), the slope coefficient k_i is obtained, and then the coefficient b_i is obtained), find the two vertices along the strip direction, and calculate the intersection point information of the rectangle and each line segment through the relationship between the vertices of the four line segments and the rectangular region (completely falling within the rectangular region / having an intersection point with the left boundary of the rectangular region / having an intersection point with the right boundary of the rectangular region).

[0082] According to the target point coordinate vector and the number of strips, the starting and ending coordinate information of each strip (the starting coordinate longitude and latitude information in the strip length direction) is obtained in turn.

[0083] The length of each strip is L_Strip(s1)=XF s1 –XB s1 , s1 = 1,2,3…5, where XF s1 , XB s1 are the front coordinate and the back coordinate of the strip obtained by the calculation in step ⑤; the lengths of all strips are summed to obtain the total effective length of the strips.

[0084] ⑦ Determine the total scanning length of the strips determined in five scanning directions respectively, select the optimal final regional scanning direction, and then determine whether to use active scanning or passive scanning. If it is active scanning, go to step ⑧; if it is passive scanning, go to step ⑨.

[0085] Calculate the effective length L_Strip(s1) of the strip scanning obtained in five scanning directions, and obtain the minimum number of strips minN_Strip in the active segmentation method = Min(L_Strip);

[0086] If the scanning direction corresponding to the selected minimum effective scanning strip length minN_Strip is theta_Scan0, that is, the along-track scanning direction, then the satellite's scanning method for the quadrilateral region is passive scanning, and go to step ⑨.

[0087] If the scanning direction corresponding to the selected minimum effective scanning strip length minN_Strip is not theta_Scan0, that is, the along-edge scanning direction (the direction of any side), then the satellite's scanning method for the quadrilateral region is active scanning, and go to step ⑧.

[0088] ⑧ Active scanning (along-edge scanning): Directly output the strip clipping result.

[0089] Output the three-dimensional coordinate information of the five points of the strips YL_i (left), YM_i (middle), YR_i (right), XF_i (front), and XB_i (rear) in the format of YL_i (left), YM_i (middle), YR_i (right), XF_i (front), XB_i (rear), and obtain the strip cutting result.

[0090] ⑨ Passive scanning (along-track scanning): Fine-tune the strip clipping result according to the sub-satellite point swath of the satellite scanning point.

[0091] The fine-tuning method is as follows:

[0092] Based on step ⑤, according to the scanning direction theta_Scan0 or theta_Scan i , after determining the maximum quadrilateral envelope (Max_Vy, Min_Vy, Max_Vx, Min_Vx) of the quadrilateral region scanning, the sub-satellite point swath mW_Swath when calculating the number of strips is a fixed value. If it is determined that the scanning direction is along the track direction theta_Scan0 for scanning, then due to the difference in imaging angles, the swath of the ground scanning will be different. It is necessary to update and calculate the imaging swath according to the imaging viewing angle Va and the sub-satellite point swath mW_Swath of the camera, and thus determine the swath of each strip.

[0093] The calculation steps of the number of strips and the width of each strip are updated as follows

[0094] The coordinate description of the first strip is:

[0095] The left coordinate of the strip is: YL_(1) = Min_Vy; % left

[0096] The middle coordinate of the strip is: YM_(1) = YL_(1) + 0.5 * mW_Swath(1); % middle

[0097] The right coordinate of the strip is: YR_(1) = YL_(1) + mW_Swath(1); % right

[0098] The front coordinate of the strip is: XF_(1) = Max_Vx; % front

[0099] The back coordinate of the strip is: XB_(1) = Min_Vx; % back

[0100] In the above formula, mW_Swath(1) is updated in real time by the satellite according to the current imaging view angle Va to the ground, the field of view angle range, and the orbital altitude. mW_Swath(i) is the width of the i-th strip, which is updated in real time by the satellite according to the current imaging view angle Va to the ground, the field of view angle range, and the orbital altitude.

[0101] The coordinate descriptions of the remaining strips are as follows:

[0102] The coordinates of each strip (i) relative to the previous strip (i - 1) are:

[0103] The left coordinate of the strip is: YL_(i) = YL_(i - 1) + mW_Swath(i); % left

[0104] The middle coordinate of the strip is: YM_(i) = YL_(i) + 0.5 * mW_Swath(i); % middle

[0105] The right coordinate of the strip is: YR_(i) = YL_(i) + mW_Swath(i); % right

[0106] The front coordinate of the strip is: XF_(i) = XF_(1); % front

[0107] The back coordinate of the strip is: XB_(i) = XB_(1); % back

[0108] Until That is, the sum of the widths of each strip is greater than the rectangular outer envelope of the quadrilateral region.

[0109] In the above formula, W_Evp = Max_Vy - Min_Vy is the width of the rectangular outer envelope of the quadrilateral region target rectangle. Is the total width of the strips that have been arranged so far, which should be lower than the width of the rectangular outer envelope.

[0110] The content not described in detail in the specification of the present invention belongs to the well-known technology of those skilled in the art.

[0111] Although the present invention has been disclosed above in preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and decorations made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention all fall within the protection scope of the technical solution of the present invention.

Claims

1. An on-board autonomous adaptive strip segmentation method for agile satellites, characterized in that Including: S1. Determine the search quadrilateral region, as well as the imaging satellite category and payload parameters; S2. Obtain the sub-satellite point track direction according to the satellite orbital elements; S3. Obtain the coordinates of the geometric center point of the region based on the coordinates of the 4 vertex points of the quadrilateral region; S4. Obtain the scanning direction of the agile satellite scanning along the 4 sides of the quadrilateral region; S5. Based on the to-be-determined scanning direction, respectively determine the maximum quadrilateral envelope of the quadrilateral region scanning, and determine the number of scanning strips according to the scanning width; S6. Adaptively adjust and trim the scanning strips according to the line segments formed by the 4 sides of the quadrilateral region; S7. Respectively determine the total scanning length of the strips according to the to-be-determined scanning direction, preferably select the final regional scanning direction, and then determine whether to use active scanning or passive scanning. If it is active scanning, go to step S8; if it is passive scanning, go to step S9; S8. Directly output the strip trimming result; S9. Fine-tune the strip trimming result according to the sub-satellite point width of the satellite scanning point and then output.

2. The on-board autonomous adaptive strip segmentation method for agile satellites according to claim 1, characterized in that In S1, determining the search quadrilateral region includes the coordinates of the 4 vertex points of the quadrilateral region, and the payload parameters at least include the field of view angle and the imaging width.

3. The on-board autonomous adaptive strip segmentation method for agile satellites according to claim 1, characterized in that In S2, obtain the satellite orbital elements at the target detection moment of the quadrilateral region by extrapolation, and calculate the sub-satellite point track direction of the satellite at the target detection moment according to the argument of latitude u and the orbital inclination i.

4. The on-board autonomous adaptive strip segmentation method for agile satellites according to claim 1, characterized in that In S3, the coordinates of the geometric center point of the quadrilateral region include the coordinates in the Earth-fixed coordinate system and the geodetic coordinates in the Earth coordinate system. Further, obtain the coordinate transformation matrix from the Earth-fixed coordinate system to the local northeast celestial coordinate system of the center of the quadrilateral region according to the Earth-fixed coordinate of the center point of the quadrilateral region.

5. The on-board autonomous adaptive strip segmentation method for agile satellites according to claim 1, characterized in that In S5, based on the to-be-determined scanning direction, respectively determine the maximum quadrilateral envelope of the quadrilateral region scanning, and determining the number of scanning strips according to the scanning width specifically includes: Obtain the transformation matrix C_PE from the Earth-fixed coordinate system to the local northeast celestial coordinate system of the center point of the quadrilateral region according to the coordinates of the center of the quadrilateral region, and the scanning angle theta_Scan in the to-be-determined scanning direction, construct the characteristic coordinate system of the quadrilateral region, with the origin at the centroid of the quadrilateral region, the X-axis is consistent with the satellite scanning direction, and the Z-axis points from the Earth center to the row center of the quadrilateral region; thus, the transformation matrix from the Earth-fixed coordinate system to the characteristic coordinate system along the satellite scanning direction of the center point of the quadrilateral target region is C_VE = Rz(theta_Scan)*C_PE; where, theta_Scan is the scanning angle theta_Scan in the to-be-determined scanning direction of the satellite for the quadrilateral region, and Rz(theta_Scan) is the coordinate transformation matrix rotating around the Z-axis by theta_Scan; Obtain the coordinate points of the 4 vertex points r_s_E(i), i = 1, 2,..., 4 of the quadrilateral region in the target characteristic coordinate system according to the transformation matrix C_VE, that is, 4 characteristic point vectors r_s_V(i) = C_VE*r_s_E(i), i = 1, 2,..., 4; Obtain the rectangular outer envelope of the 4 vertex points along the to-be-determined scanning direction according to the characteristic point vector coordinates r_s_V(i) of the 4 vertex points; Max_Vy = max(r_s_V(2, :)); Min_Vy = min(r_s_V(2, :)); Max_Vx = max(r_s_V(1, :)); Min_Vx = min(r_s_V(1, :)); The width of the rectangular envelope is obtained as: W_Evp = Max_Vy - Min_Vy; the length of the envelope is: Max_Vx - Min_Vx; The calculation formula for the number of satellite scan strips is as follows: N_Strip = W_Evp / mW_Swath, where W_Evp is the width envelope in the vertical scan direction and mW_Swath is the width of the camera's sub-satellite point swath; For each strip, three-dimensional vectors YL_i, YM_i, YR_i, XF_i, XB_i are used to describe its position; among them, YL_i, YM_i, YR_i describe the width information of the strip, including the left, middle, and right position coordinates, and XF_i, XB_i describe the length information of the strip, where F represents the front position coordinate and B represents the rear position coordinate; The coordinate description of the first strip is: The left coordinate of the strip is: YL_(1) = Min_Vy; The middle coordinate of the strip is: YM_(1) = YL_(1) + 0.5 * mW_Swath; The right coordinate of the strip is: YR_(1) = YL_(1) + mW_Swath; The front coordinate of the strip is: XF_(1) = Max_Vx; The rear coordinate of the strip is: XB_(1) = Min_Vx; The coordinate descriptions of the remaining N_Strip - 1 strips are: The coordinates of each strip i relative to the previous strip i - 1 are: The left coordinate of the strip is: YL_(i) = YL_(i - 1) + mW_Swath; The middle coordinate of the strip is: YM_(i) = YL_(i) + 0.5 * mW_Swath; The right coordinate of the strip is: YR_(i) = YL_(i) + mW_Swath; The front coordinate of the strip is: XF_(i) = XF_(1); The rear coordinate of the strip is: XB_(i) = XB_(1).

6. The agile satellite on-board autonomous adaptive strip segmentation method according to claim 5, wherein The adaptive adjustment and clipping of the scan strips in S6 specifically include: Judging the intersection points of the rectangular strip and each boundary line segment of the quadrilateral region target: for each line segment, by the method of the straight-line equation, the slope coefficient k_i is obtained, and then the coefficient b_i is obtained, and the two vertices along the strip direction are found, and the intersection information of the rectangle and each line segment is calculated through the relationship between the vertices of the 4 line segments and the rectangular region; According to the target point coordinate vector and the number of strips, the starting and ending coordinate information of each strip is obtained in turn; The length of each strip is L_Strip(s1) = XF s1 – XB s1 , s1 = 1, 2, 3…5, where XF s1 , XB s1 are the calculated front and rear coordinates of the strip in S5; summing up the lengths of all strips gives the total effective length of the strips.

7. The agile satellite on-board autonomous adaptive strip segmentation method according to claim 1, characterized in that The method for determining whether to use active scanning or passive scanning in S7 is: Calculate the effective length L_Strip(s1) of the strip scan obtained in the to-be-determined scan direction, and obtain the minimum value of the number of strips minN_Strip = Min(L_Strip) in the active segmentation method; If the scan direction corresponding to the minimum effective scan strip length minN_Strip selected is theta_Scan0, that is, the along-track scan direction, then the satellite's scan mode for the quadrilateral region is passive scanning; theta_Scan0 is the sub-satellite point track direction obtained in S2; If the scanning direction corresponding to the minimum effective scanning strip length minN_Strip selected is not theta_Scan0, the scanning mode of the satellite for the quadrilateral region is active scanning. S8. Directly output the strip clipping result; S9. After fine-tuning the strip clipping result according to the sub-satellite point swath of the satellite scanning point, output it.

8. The agile satellite on-board autonomous adaptive strip segmentation method according to claim 5, wherein The method for fine-tuning the strip clipping result in S9 is as follows: According to the scan direction theta_Scan0 or theta_Scan i , after determining the maximum quadrilateral envelope for the quadrilateral area scan, the nadir width mW_Swath when calculating the number of strips is a fixed value. If it is determined that the scan direction is along-track scanning in theta_Scan0, it is necessary to update and calculate the imaging width based on the imaging view angle Va and the nadir width mW_Swath of the camera, and thus determine the width of each strip; The calculation steps for the number of strips and the width of each strip are updated as follows: The coordinate description of the first strip is: The left coordinate of the strip is: YL_(1) = Min_Vy; The middle coordinate of the strip is: YM_(1) = YL_(1) + 0.5 * mW_Swath(1); The right coordinate of the strip is: YR_(1) = YL_(1) + mW_Swath(1); The front coordinate of the strip is: XF_(1) = Max_Vx; The back coordinate of the strip is: XB_(1) = Min_Vx; In the above formula, mW_Swath(1) is updated in real time by the satellite according to the current imaging view angle Va to the ground, the field of view angle range, and the orbital altitude; mW_Swath(i) is the swath width of the i-th strip, which is updated in real time by the satellite according to the current imaging view angle Va to the ground, the field of view angle range, and the orbital altitude; The coordinate description of the remaining strips is: The coordinates of each strip i relative to the previous strip i - 1 are: The left coordinate of the strip is: YL_(i) = YL_(i - 1) + mW_Swath(i); The middle coordinate of the strip is: YM_(i) = YL_(i) + 0.5 * mW_Swath(i); The right coordinate of the strip is: YR_(i) = YL_(i) + mW_Swath(i); The front coordinate of the strip is: XF_(i) = XF_(1); The back coordinate of the strip is: XB_(i) = XB_(1); until that is, the sum of the widths of the respective strips is greater than the rectangular envelope of the quadrilateral region; In the above formula, W_Evp = Max_Vy - Min_Vy is the width of the outer envelope of the target rectangle in the quadrilateral region. It is the total width of the strips already arranged and should be less than the width of the rectangular outer envelope.

9. A computer program product stored on a non-transitory computer-readable medium, the computer program product comprising program code for implementing the method according to any one of claims 1 to 8.

10. An electronic device, comprising: A processor; And A memory for storing computer program instructions; Wherein when the computer program instructions are loaded and run by the processor, the processor executes the method according to any one of claims 1 to 8.

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