Solar flare autonomous avoidance method and system facing optical remote sensing satellite

Abstract

The invention provides an optical remote sensing satellite-oriented solar flare autonomous avoidance method and system. The method comprises the following steps of: 1, giving an imaging moment of a satellite to a focused target; 2, calculating the position of a satellite in an inertial system; 3, calculating the position of the sun under the inertial system; 4, calculating the position of the flare spot under the inertial system; 5, judging whether the visual axis points to the same side as the flare spot; 6, judging whether the flare spot is located in the field of view of the camera; and 7, carrying out flare spot autonomous avoidance task planning. According to the method, the problems of saturation distortion of large-area pixels of remote sensing images, missing of key information of a target area, reduction of satellite observation efficiency and the like caused by flare spots in a camera view field when an optical remote sensing satellite observes a specific area at specific time can be solved.

Description

Technical Field

[0001] The present invention relates to the field of satellite remote sensing technology, and in particular to a method and system for autonomously avoiding solar glare for an optical remote sensing satellite. Background Art

[0002] For wide-field-of-view optical remote sensing satellites conducting ocean surface observation missions, glare points, created when sunlight incident on the sea surface reflects off the surface, may enter the camera's field of view. Due to the high brightness of these glare points, large areas of the remote sensing imagery are saturated and distorted, resulting in the loss of critical information and an inability to meet the dynamic observation needs of key areas. Therefore, it is urgent to develop autonomous solar glare avoidance methods for optical remote sensing satellites. When glare points appear within the camera's field of view, the satellite can autonomously avoid them, preventing the remote sensing imagery from being contaminated by excessive glare noise and hindering optimal observation efficiency.

[0003] After searching, the literature 1: Wen Yuan, Yang Yong, Dai Haishan, et al. Research on high-precision two-dimensional pointing algorithm for ocean flares [J]. Infrared, 2018, 39(11): 28-33. A two-dimensional tracking calculation method for ocean flares taking into account the ellipticity of the earth is studied. The calculation process of the ocean flare position and the calculation formula of the two-dimensional pointing mirror rotation angle are given, so that the pointing mirror can continuously track the ocean flare. However, when calculating the ocean flare position, this method uses the bisection method for iterative approximation, which is computationally intensive. When using the two-dimensional pointing mirror to track flares, the two-dimensional pointing mirror is regarded as a narrow-field-of-view camera for observation, which is not suitable for wide-field-of-view cameras, and no method for the satellite to autonomously avoid flares is given.

[0004] Reference 2: Yin Jianjie, Xu Pengmei, Wang Caiqin, et al. A method for locating the solar flare orientation in remote sensing detection [J]. Space Return and Remote Sensing, 2017, 38(02): 34-40. This paper presents a method for locating the solar flare orientation using the geometric relationship between the satellite, the sun, and the flare point. However, this method uses a bisection method for iterative approximation when calculating the flare point position, which is computationally intensive. Furthermore, this method does not address flare avoidance for wide-field-of-view cameras, and does not provide a method for autonomous satellite flare avoidance.

[0005] Patent Document 1: A method and electronic device for avoiding water flare in optical remote sensing satellite images (CN113805207A). This method avoids water flare in optical remote sensing satellite images by avoiding the difference in satellite and solar altitude angles, ensuring that the difference in satellite and solar azimuth angles is within a preset range of altitude and azimuth differences that can produce water flare. However, this method does not involve calculating the position of ocean flare and is not suitable for avoiding flare in wide-field-of-view cameras.

[0006] Patent Document 2: A greenhouse gas observation method based on calculation of the subsatellite point and flare spot position (CN117761012A). This method uses the calculated relationship between the subsatellite point and the flare spot position to enable the satellite to autonomously switch observation modes and acquire high-quality greenhouse gas observation data. However, this method uses a binary search method for iterative approximation when calculating the flare spot position, which is computationally intensive. Furthermore, it does not address flare avoidance for wide-field-of-view cameras and does not provide a method for autonomous satellite flare avoidance.

[0007] Patent Document 3: "Adaptive Polarization Detection Device and Method for Sea Surface Targets with Solar Glare Suppression" (CN114720388A) proposes a method for suppressing sea surface glare using polarization, enabling automated glare suppression during motion. However, this method primarily focuses on "suppressing" glare and does not address "avoiding" it.

[0008] None of the above documents and patents provide a method for autonomously avoiding solar glare for wide-field-of-view optical remote sensing satellites. Summary of the Invention

[0009] In view of the defects in the prior art, the purpose of the present invention is to provide a method and system for autonomous solar glare avoidance for optical remote sensing satellites.

[0010] According to the present invention, a method for autonomously avoiding solar glare for an optical remote sensing satellite is provided, comprising:

[0011] Step S1: According to the satellite's mission requirements and the satellite's on-orbit constraints, mission planning is performed to provide the satellite's imaging time T0 of the key target and the attitude angle at the imaging time;

[0012] Step S2: Calculate the satellite's position P in the inertial system based on the six satellite orbit numbers s =(x s ,y s ,z s );

[0013] Step S3: Calculate the position P of the sun in the inertial system based on the Earth's orbital parameters h =(x h ,y h ,z h );

[0014] Step S4: Based on the formation principle of the flare point, establish the spatial geometric relationship between the sun, satellite, earth and the flare point, and calculate the position P of the flare point in the inertial system. m ;

[0015] Step S5: Determine whether the visual axis is pointing to the same side as the flare point. If Indicates that the camera's visual axis and the flare point are in the same direction, and the flare point is within the camera's field of view. Go to step S6. If This means that the camera's visual axis and the flare point are not in the same direction, and the flare point will not be within the camera's field of view, and the process ends. is the vector of the camera’s visual axis in the inertial coordinate system, is the unit vector of the satellite pointing to the flare point;

[0016] Step S6: Determine whether the flare point is within the camera field of view. If θ min ≤α s +χ x , indicating that the flare point is within the camera field of view, and then proceed to step S7; if θ min >α s +χ x , indicating that the flare point is outside the camera's field of view, and the process ends; where χ x is the half field of view angle of the camera along the track, α s is the sun angle, θ min is the minimum angle between the unit vector pointing to the flare point and the satellite's visual plane;

[0017] Step S7: Carry out autonomous flare avoidance mission planning. When there is a solar flare within the camera's field of view, the flare is avoided by increasing or decreasing the satellite's elevation angle without affecting the quality of the remote sensing image.

[0018] Furthermore, in step S2, the position P of the satellite in the inertial system s The calculation formula is:

[0019]

[0020] Among them, (x s ,y s ,z s ) represent the x-axis, y-axis, and z-axis coordinates of the satellite in the inertial system; a, e, i, Ω, ω, and γ represent the semi-major axis, eccentricity, orbital inclination, right ascension of the ascending node, argument of perigee, and true anomaly, respectively, and are called the six orbital numbers; R z (-Ω) represents the coordinate transformation matrix of the reverse rotation angle Ω around the z-axis; R x (-i) represents the coordinate transformation matrix of the angle i in the opposite direction around the x-axis; R z (-ω) represents the coordinate transformation matrix for the reverse rotation angle ω around the z-axis.

[0021] Furthermore, in step S3, the position P of the sun in the inertial system h The calculation formula is:

[0022]

[0023] Among them, (x h ,y h ,z h ) represent the x-axis, y-axis, and z-axis coordinates of the sun in the inertial system; a sun represents the semi-major axis of the Earth's orbit; e sun represents the eccentricity of the Earth's orbit; γ sun represents the true anomaly of the Earth's orbit; Λ represents the sun's ecliptic longitude; Indicates the obliquity of the ecliptic.

[0024] Furthermore, in step S4, the position P of the flare point in the inertial system m The calculation formula is:

[0025]

[0026] Among them, R e represents the radius of the Earth; The unit vector representing the direction from the center of the Earth to the flare point is calculated as:

[0027]

[0028] in, represents the unit vector pointing from the center of the Earth to the satellite; Represents the normal vector of the plane where the satellite, the sun and the earth are located. The calculation formula is:

[0029]

[0030] in, represents the unit vector pointing from the center of the Earth to the Sun; It represents the angle between the unit vector from the center of the Earth pointing to the Sun and the unit vector from the center of the Earth pointing to the satellite;

[0031] α represents the angle between the unit vector from the center of the Earth pointing to the satellite and the unit vector from the center of the Earth pointing to the flare point. The calculation formula is:

[0032]

[0033] Where H represents the orbital altitude of the satellite.

[0034] Furthermore, in step S5, the vector of the camera visual axis in the inertial coordinate system is The calculation formula is:

[0035]

[0036] Among them, A ob A is the transformation matrix from the satellite body coordinate system to the orbit coordinate system;io is the transformation matrix from orbital coordinate system to inertial coordinate system; is the vector of the camera's visual axis in the camera coordinate system, and the calculation formula is:

[0037]

[0038] Where ρ is the off-axis angle of the camera.

[0039] Furthermore, in step S5, the unit vector of the satellite pointing to the flare point The calculation formula is:

[0040]

[0041] Where β represents the incident angle of sunlight, represents the unit vector pointing from the center of the Earth to the flare point, Represents the normal vector of the plane where the satellite, the sun, and the earth are located.

[0042] Furthermore, in step S6, the minimum angle θ between the unit vector pointing to the flare point and the satellite's visual plane is min The calculation process is as follows:

[0043] The vector of the satellite pointing to point A on the leftmost side of the remote sensing image The vector of the satellite pointing to point B on the rightmost side of the remote sensing image

[0044] Among them, χ y is the half field of view angle of the vertical track camera; the superscript T indicates transposition, and the vector Convert to unit vector

[0045] Furthermore, if In this case, the projection of the flare point is inside the image AB. min The calculation formula is:

[0046]

[0047] in, Represents the unit normal vector of the satellite's viewing surface, and the calculation formula is:

[0048]

[0049] in, Represents a unit vector and The angle between

[0050] if In this case, the projection of the flare point is outside the image AB.min The calculation formula is:

[0051]

[0052] Furthermore, in step S7, the calculation formula for the imaging time T1 of the focused target is:

[0053] T1=T0±Δη / ω1

[0054] Where ω1 is the satellite's orbital angular velocity; Δη is the corresponding satellite phase change when the satellite's pitch angle changes. The calculation formula is:

[0055]

[0056] Among them, θ1 is the satellite pitch angle before the change; θ2 is the satellite pitch angle after the change.

[0057] According to the present invention, a solar glare autonomous avoidance system for an optical remote sensing satellite is provided, comprising:

[0058] Module M1: Performs mission planning based on the satellite's mission requirements and on-orbit constraints, and provides the satellite's imaging time T0 and attitude angle at the imaging time for the key target.

[0059] Module M2: Calculate the satellite's position P in the inertial system based on the six numbers of the satellite orbit s =(x s ,y s ,z s );

[0060] Module M3: Calculate the position P of the sun in the inertial system based on the parameters of the Earth's orbit h =(x h ,y h ,z h );

[0061] Module M4: Based on the formation principle of flare points, establish the spatial geometric relationship between the sun, satellite, earth and flare points, and calculate the position P of the flare point in the inertial system. m ;

[0062] Module M5: Determine whether the visual axis is pointing to the same side as the flare point. If Indicates that the camera's visual axis and the flare point are in the same direction. The flare point will be within the camera's field of view. Entering module M6, if This means that the camera's visual axis and the flare point are not in the same direction, and the flare point will not be within the camera's field of view, and the process ends. is the vector of the camera’s visual axis in the inertial coordinate system, is the unit vector of the satellite pointing to the flare point;

[0063] Module M6: Determine whether the flare point is within the camera field of view. If θ min ≤α s +χ x , indicating that the flare point is within the camera field of view and enters module M7; if θ min >α s +χ x , indicating that the flare point is outside the camera's field of view, and the process ends; where χ x is the half field of view angle of the camera along the track, α s is the sun angle, θ min is the minimum angle between the unit vector pointing to the flare point and the satellite's visual plane;

[0064] Module M7: Carry out autonomous flare avoidance mission planning. When there is a solar flare in the camera's field of view, the flare is avoided by increasing or decreasing the satellite's elevation angle without affecting the quality of the remote sensing image.

[0065] Compared with the prior art, the present invention has the following beneficial effects:

[0066] The present invention proposes an autonomous solar glare avoidance method for optical remote sensing satellites, which can rapidly determine the location of glare points with minimal computational effort and resource consumption. Furthermore, the present invention innovatively proposes a method for avoiding glare points when the satellite payload is a wide-field-of-view camera. This method addresses the problems of large-area pixel saturation and distortion, loss of key information about the target area, and reduced satellite observation efficiency caused by solar glare interference in remote sensing images. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0068] Figure 1 This is a flow chart of a method for autonomously avoiding solar glare for optical remote sensing satellites according to the present invention;

[0069] Figure 2 Schematic diagram of the spatial geometric relationship of the six orbital elements of the present invention;

[0070] Figure 3 Schematic diagram of the spatial geometric relationship among the sun, satellite, earth and flare point of the present invention;

[0071] Figure 4 Schematic diagram of the spatial geometric relationship between the camera field of view angle, off-axis angle and remote sensing image of the present invention;

[0072] Figure 5Schematic diagram of the spatial geometric relationship among satellites, remote sensing images and flare points of the present invention. DETAILED DESCRIPTION

[0073] The present invention will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several changes and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0074] like Figure 1 As shown, the present invention provides a method for autonomously avoiding solar glare for an optical remote sensing satellite, comprising:

[0075] Step S1: Based on the satellite's mission requirements and constraints such as the satellite's real-time orbit and solar altitude angle, the ground performs mission planning and provides the satellite's imaging time T0 of the key target and the attitude angle at the imaging time.

[0076] Step S2: Calculate the satellite's position P in the inertial system based on the six satellite orbit numbers s =(x s ,y s ,z s ).

[0077] The position P of the satellite in the inertial system s The calculation formula is:

[0078]

[0079] Among them, (x s ,y s ,z s ) represent the x-axis, y-axis, and z-axis coordinates of the satellite in the inertial system; (a, e, i, Ω, ω, γ) represent the semi-major axis, eccentricity, orbital inclination, right ascension of the ascending node, argument of perigee, and true anomaly, respectively. The above six parameters can represent the motion characteristics of the satellite in space and are called the six orbital elements. The spatial geometric relationship diagram of the six orbital elements is shown in the figure below. Figure 2 As shown. z (-Ω) represents the coordinate transformation matrix of the reverse rotation angle Ω around the z-axis; R x (-i) represents the coordinate transformation matrix of the angle i in the opposite direction around the x-axis; R z (-ω) represents the coordinate transformation matrix for the reverse rotation angle ω around the z-axis.

[0080] Step S3: Calculate the position P of the sun in the inertial system based on the Earth's orbital parameters h =(x h ,y h,z h ).

[0081] The position of the sun in the inertial system P h The calculation formula is:

[0082]

[0083] Among them, (x h ,y h ,z h ) represent the x-axis, y-axis, and z-axis coordinates of the sun in the inertial system; a sun represents the semi-major axis of the Earth's orbit; e sun represents the eccentricity of the Earth's orbit; γ sun represents the true anomaly of the Earth's orbit; Λ represents the sun's ecliptic longitude; Indicates the obliquity of the ecliptic.

[0084] Step S4: According to the formation principle of flare points, the spatial geometric relationship between the sun, satellite, earth and flare points is established. The spatial geometric relationship between the sun, satellite, earth and flare points is as follows: Figure 3 As shown, calculate the position P of the flare point in the inertial system m .

[0085] The position P of the flare point in the inertial system m The calculation formula is:

[0086]

[0087] Among them, R e represents the radius of the Earth; The unit vector representing the direction from the center of the Earth to the flare point is calculated as:

[0088]

[0089] in, represents the unit vector pointing from the center of the Earth to the satellite; Represents the normal vector of the plane where the satellite, the sun and the earth are located. The calculation formula is:

[0090]

[0091] in, represents the unit vector pointing from the center of the Earth to the Sun; It represents the angle between the unit vector from the center of the Earth pointing to the Sun and the unit vector from the center of the Earth pointing to the satellite.

[0092] α represents the angle between the unit vector from the center of the Earth pointing to the satellite and the unit vector from the center of the Earth pointing to the flare point. The calculation formula is:

[0093]

[0094] Where H represents the orbital altitude of the satellite.

[0095] because R e If α and H are known, the numerical solution of α can be obtained by Newton iteration method. If the computing resources on the satellite are limited, it is also possible to pre-store The corresponding relationship with α can be used to quickly obtain the value of α by looking up the table.

[0096] Step S5: Determine whether the visual axis is pointing to the same side as the flare point. Indicates that the camera's visual axis and the flare point are in the same direction, and the flare point may be within the camera's field of view, and then proceeds to step S6. This means that the camera's visual axis and the flare point are not in the same direction, and the flare point is not within the camera's field of view, and the process ends. is the vector of the camera's visual axis in the inertial coordinate system; is the unit vector pointing from the satellite to the flare point.

[0097] The vector of the camera's visual axis in the inertial coordinate system The calculation formula is:

[0098]

[0099] Among them, A ob A is the transformation matrix from the satellite body coordinate system to the orbit coordinate system; io is the transformation matrix from orbital coordinate system to inertial coordinate system; is the vector of the camera's visual axis in the camera coordinate system, and the calculation formula is:

[0100]

[0101] Where ρ is the off-axis angle of the camera. The spatial geometric relationship between the camera field of view angle, off-axis angle and remote sensing image is as follows: Figure 4 shown.

[0102] The unit vector of the satellite pointing to the flare point The calculation formula is:

[0103]

[0104] Here, β represents the incident angle of sunlight.

[0105] Step S6: Determine whether the flare point is within the camera field of view. min ≤α s +χ x , indicating that the flare point is within the camera field of view, and then proceed to step S7; if θmin >α s +χ x , indicating that the flare point is outside the camera's field of view, and the process ends. x is the half field of view angle of the camera along the track; α s is the sun angle, generally 0.54°; θ min It is the minimum angle between the unit vector pointing to the flare point of the satellite and the satellite's visual plane.

[0106] The minimum angle θ between the satellite's unit vector pointing to the flare point and the satellite's visual plane min The calculation process is as follows:

[0107] The vector of the satellite pointing to the leftmost point A in the remote sensing image can be used Indicates that the vector of the satellite pointing to the rightmost point B in the remote sensing image can be used In which, χ y is the half field of view angle of the vertical camera; the superscript T indicates transposition. Convert to unit vector

[0108] The spatial geometric relationship between satellite, remote sensing images and flare points is as follows Figure 5 If In this case, the projection of the flare point is inside the image AB. min The calculation formula is:

[0109]

[0110] in, Represents the unit normal vector of the satellite's viewing surface, and the calculation formula is:

[0111]

[0112] in, Represents a unit vector and The angle between them.

[0113] if In this case, the projection of the flare point is outside the image AB. min The calculation formula is:

[0114]

[0115] Step S7: Conduct autonomous flare avoidance mission planning. When a solar flare is present within the camera's field of view, the flare can be avoided by increasing or decreasing the satellite's elevation angle, without compromising image quality. Changing the satellite's elevation angle requires recalculating the imaging time T1 for the target of interest.

[0116] The calculation formula for the imaging time T1 of the key target is:

[0117] T1=T0±Δη / ω1

[0118] Where ω1 is the satellite's orbital angular velocity; Δη is the corresponding satellite phase change when the satellite's pitch angle changes. The calculation formula is:

[0119]

[0120] Among them, θ1 is the satellite pitch angle before the change; θ2 is the satellite pitch angle after the change.

[0121] The present invention also provides an autonomous solar glare avoidance system for optical remote sensing satellites. The autonomous solar glare avoidance system for optical remote sensing satellites can be implemented by executing the process steps of the autonomous solar glare avoidance method for optical remote sensing satellites. That is, those skilled in the art can understand the autonomous solar glare avoidance method for optical remote sensing satellites as a preferred embodiment of the autonomous solar glare avoidance system for optical remote sensing satellites. The system includes:

[0122] Module M1: Performs mission planning based on the satellite's mission requirements and on-orbit constraints, and provides the satellite's imaging time T0 and attitude angle at the imaging time for the key target.

[0123] Module M2: Calculate the satellite's position P in the inertial system based on the six numbers of the satellite orbit s =(x s ,y s ,z s );

[0124] Module M3: Calculate the position P of the sun in the inertial system based on the parameters of the Earth's orbit h =(x h ,y h ,z h );

[0125] Module M4: Based on the formation principle of flare points, establish the spatial geometric relationship between the sun, satellite, earth and flare points, and calculate the position P of the flare point in the inertial system. m ;

[0126] Module M5: Determine whether the visual axis is pointing to the same side as the flare point. If Indicates that the camera's visual axis and the flare point are in the same direction. The flare point will be within the camera's field of view. Entering module M6, if This means that the camera's visual axis and the flare point are not in the same direction, and the flare point will not be within the camera's field of view, and the process ends. is the vector of the camera’s visual axis in the inertial coordinate system, is the unit vector of the satellite pointing to the flare point;

[0127] Module M6: Determine whether the flare point is within the camera field of view. If θ min ≤α s +χ x , indicating that the flare point is within the camera field of view and enters module M7; if θ min >α s +χ x , indicating that the flare point is outside the camera's field of view, and the process ends; where χ x is the half field of view angle of the camera along the track, α s is the sun angle, θ min is the minimum angle between the unit vector pointing to the flare point and the satellite's visual plane;

[0128] Module M7: Carry out autonomous flare avoidance mission planning. When there is a solar flare in the camera's field of view, the flare is avoided by increasing or decreasing the satellite's elevation angle without affecting the quality of the remote sensing image.

[0129] Those skilled in the art will appreciate that, in addition to implementing the system and its various devices, modules, and units provided by the present invention in purely computer-readable program code, it is entirely possible to implement the same functions of the system and its various devices, modules, and units provided by the present invention in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, the system and its various devices, modules, and units provided by the present invention can be considered a hardware component, and the devices, modules, and units included therein for implementing various functions can also be considered as structures within the hardware component; the devices, modules, and units for implementing various functions can also be considered as both software modules implementing the method and structures within the hardware component.

[0130] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. The embodiments of this application and the features in the embodiments may be combined with each other in any manner unless there is a conflict.

Claims

1. A method for autonomously avoiding solar glare for an optical remote sensing satellite, characterized in that: include: Step S1: According to the satellite's mission requirements and the satellite's on-orbit constraints, mission planning is performed to provide the satellite's imaging time T0 of the key target and the attitude angle at the imaging time; Step S2: Calculate the satellite's position P in the inertial system based on the six satellite orbit numbers s =(x s ,y s ,z s ); Step S3: Calculate the position P of the sun in the inertial system based on the Earth's orbital parameters h =(x h ,y h ,z h ); Step S4: Based on the formation principle of the flare point, establish the spatial geometric relationship between the sun, satellite, earth and the flare point, and calculate the position P of the flare point in the inertial system. m ; Step S5: Determine whether the visual axis is pointing to the same side as the flare point. If Indicates that the camera's visual axis and the flare point are in the same direction, and the flare point is within the camera's field of view. Go to step S6. If This means that the camera's visual axis and the flare point are not in the same direction, and the flare point will not be within the camera's field of view, and the process ends. is the vector of the camera’s visual axis in the inertial coordinate system, is the unit vector of the satellite pointing to the flare point; Step S6: Determine whether the flare point is within the camera field of view. If θ min ≤α s +χ x , indicating that the flare point is within the camera field of view, and then proceed to step S7; if θ min >α s +χ x , indicating that the flare point is outside the camera's field of view, and the process ends; where χ x is the half field of view angle of the camera along the track, α s is the sun angle, θ min is the minimum angle between the unit vector pointing to the flare point and the satellite's visual plane; Step S7: Carry out autonomous flare avoidance mission planning. When there is a solar flare within the camera's field of view, the flare is avoided by increasing or decreasing the satellite's elevation angle without affecting the quality of the remote sensing image.

2. The method for autonomously avoiding solar glare for an optical remote sensing satellite according to claim 1, characterized in that: In step S2, the position P of the satellite in the inertial system s The calculation formula is: Among them, (x s ,y s ,z s ) represent the x-axis, y-axis, and z-axis coordinates of the satellite in the inertial system; a, e, i, Ω, ω, and γ represent the semi-major axis, eccentricity, orbital inclination, right ascension of the ascending node, argument of perigee, and true anomaly, respectively, and are called the six orbital numbers; R z (-Ω) represents the coordinate transformation matrix of the reverse rotation angle Ω around the z-axis; R x (-i) represents the coordinate transformation matrix of the angle i in the opposite direction around the x-axis; R z (-ω) represents the coordinate transformation matrix for the reverse rotation angle ω around the z-axis.

3. The method for autonomously avoiding solar glare for an optical remote sensing satellite according to claim 1, characterized in that: In step S3, the position P of the sun in the inertial system h The calculation formula is: Among them, (x h ,y h ,z h ) represent the x-axis, y-axis, and z-axis coordinates of the sun in the inertial system; a sun represents the semi-major axis of the Earth's orbit; e sun represents the eccentricity of the Earth's orbit; γ sun represents the true anomaly of the Earth's orbit; Λ represents the sun's ecliptic longitude; Indicates the obliquity of the ecliptic.

4. The method for autonomous solar glare avoidance for an optical remote sensing satellite according to claim 1, characterized in that: In step S4, the position P of the flare point in the inertial system is m The calculation formula is: Among them, R e represents the radius of the Earth; The unit vector representing the direction from the center of the Earth to the flare point is calculated as: in, represents the unit vector pointing from the center of the Earth to the satellite; Represents the normal vector of the plane where the satellite, the sun and the earth are located. The calculation formula is: in, represents the unit vector pointing from the center of the Earth to the Sun; It represents the angle between the unit vector from the center of the Earth pointing to the Sun and the unit vector from the center of the Earth pointing to the satellite; α represents the angle between the unit vector from the center of the Earth pointing to the satellite and the unit vector from the center of the Earth pointing to the flare point. The calculation formula is: Where H represents the orbital altitude of the satellite.

5. The method for autonomously avoiding solar glare for an optical remote sensing satellite according to claim 1, characterized in that: In step S5, the vector of the camera visual axis in the inertial coordinate system is The calculation formula is: Among them, A ob A is the transformation matrix from the satellite body coordinate system to the orbit coordinate system; io is the transformation matrix from orbital coordinate system to inertial coordinate system; is the vector of the camera's visual axis in the camera coordinate system, and the calculation formula is: Where ρ is the off-axis angle of the camera.

6. The method for autonomously avoiding solar glare for an optical remote sensing satellite according to claim 1, characterized in that: In step S5, the unit vector of the satellite pointing to the flare point The calculation formula is: Where β represents the incident angle of sunlight, represents the unit vector pointing from the center of the Earth to the flare point, Represents the normal vector of the plane where the satellite, the sun, and the earth are located.

7. The method for autonomous solar glare avoidance for an optical remote sensing satellite according to claim 1, characterized in that: In step S6, the minimum angle θ between the unit vector of the satellite pointing to the flare point and the satellite's visual plane is min The calculation process is as follows: The vector of the satellite pointing to point A on the leftmost side of the remote sensing image The vector of the satellite pointing to point B on the rightmost side of the remote sensing image Among them, χ y is the half field of view angle of the vertical track camera; the superscript T indicates transposition, and the vector Convert to unit vector 8. The method for autonomously avoiding solar glare for an optical remote sensing satellite according to claim 7, characterized in that: if In this case, the projection of the flare point is inside the image AB. min The calculation formula is: in, Represents the unit normal vector of the satellite's viewing surface, and the calculation formula is: in, Represents a unit vector and The angle between if In this case, the projection of the flare point is outside the image AB. min The calculation formula is:

9. The method for autonomously avoiding solar glare for an optical remote sensing satellite according to claim 1, characterized in that: In step S7, the calculation formula for the imaging time T1 of the focused target is: T1=T0±Δη / ω1 Where ω1 is the satellite's orbital angular velocity; Δη is the corresponding satellite phase change when the satellite's pitch angle changes. The calculation formula is: Among them, θ1 is the satellite pitch angle before the change; θ2 is the satellite pitch angle after the change.

10. An autonomous solar glare avoidance system for optical remote sensing satellites, characterized in that: include: Module M1: Performs mission planning based on the satellite's mission requirements and on-orbit constraints, and provides the satellite's imaging time T0 and attitude angle at the imaging time for the key target. Module M2: Calculate the satellite's position P in the inertial system based on the six numbers of the satellite orbit s =(x s ,y s ,z s ); Module M3: Calculate the position P of the sun in the inertial system based on the parameters of the Earth's orbit h =(x h ,y h ,z h ); Module M4: Based on the formation principle of flare points, establish the spatial geometric relationship between the sun, satellite, earth and flare points, and calculate the position P of the flare point in the inertial system. m ; Module M5: Determine whether the visual axis is pointing to the same side as the flare point. If Indicates that the camera's visual axis and the flare point are in the same direction. The flare point will be within the camera's field of view. Entering module M6, if This means that the camera's visual axis and the flare point are not in the same direction, and the flare point will not be within the camera's field of view, and the process ends. is the vector of the camera’s visual axis in the inertial coordinate system, is the unit vector of the satellite pointing to the flare point; Module M6: Determine whether the flare point is within the camera field of view. If θ min ≤α s +χ x , indicating that the flare point is within the camera field of view and enters module M7; if θ min >α s +χ x , indicating that the flare point is outside the camera's field of view, and the process ends; where χ x is the half field of view angle of the camera along the track, α s is the sun angle, θ min is the minimum angle between the unit vector pointing to the flare point and the satellite's visual plane; Module M7: Carry out autonomous flare avoidance mission planning. When there is a solar flare in the camera's field of view, the flare is avoided by increasing or decreasing the satellite's elevation angle without affecting the quality of the remote sensing image.

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