Low-cost low-orbit minisatellite attitude and orbit control system and method

Abstract

The invention discloses a low-cost low-orbit moonlet attitude and orbit control system and method, relates to the field of satellite attitude and orbit control, solves the problem that the orbit and self attitude adjustment mode of a current low-orbit satellite is unreasonable, and comprises a data analysis module, an orbit planning module, an orbit adjustment module and an attitude adjustment module, the data analysis module is used for analyzing latitude and longitude information corresponding to the image acquisition area; the orbit planning module is used for planning the standard operation orbit of the low-orbit satellite to obtain the standard operation orbit of the low-orbit satellite; the image acquisition module is used for performing image acquisition on preset coordinates of the earth surface at fixed time intervals; the orbit adjusting module is used for adjusting the orbit deviation of the low-orbit satellite when the low-orbit satellite is launched to reach a standard operation orbit; and the attitude adjustment module is used for adjusting the attitude of the low-orbit satellite when the low-orbit satellite arrives at a specified coordinate. According to the invention, intelligent regulation and control of the low-cost low-orbit moonlet orbit and the attitude of the low-orbit moonlet are realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of satellite attitude and orbit control, and in particular to a low-cost low-orbit small satellite attitude and orbit control system and method. Background Art

[0002] The attitude and orbit control system is a key system on a satellite for controlling the satellite's attitude and orbit. The system ensures that the satellite is correctly aligned with the target in orbit by sensing the satellite's attitude (such as pitch, yaw, and roll angles) and adjusting the satellite's direction according to mission requirements. It usually consists of multiple subsystems, including attitude sensing modules (such as star sensors, gyroscopes), orbit control modules (such as engines or reaction wheels), and control algorithms (such as PID control or adaptive control). The attitude control system provides real-time feedback on the satellite's attitude error and adjusts the control torque to keep or change the satellite's attitude, while the orbit control part ensures that the satellite operates in the predetermined orbit by fine-tuning the satellite's orbital parameters (such as altitude, speed, and inclination). The precise control of AOCS enables satellites to perform complex tasks such as ground imaging, communications, and scientific experiments, ensuring the long-term and stable operation of satellites.

[0003] In the prior art, after reaching the operating orbit, the low-orbit satellite has a weak ability to judge whether it is in orbit, causing the low-orbit satellite to repeatedly adjust its orbital altitude. At the same time, the low-orbit satellite takes a long time to adjust its attitude when taking ground images. When the low-orbit satellite leaves the shooting window, it is still adjusting its attitude, which leads to increased fuel consumption of the low-orbit satellite. At the same time, when the low-orbit satellite enters the shooting window, the attitude of the low-orbit satellite cannot be adjusted in advance, and the ideal shooting window is missed.

[0004] To this end, the present invention proposes a low-cost low-orbit small satellite attitude and orbit control system and method. Summary of the invention

[0005] The purpose of the present invention is to propose a low-cost low-orbit small satellite attitude and orbit control system and method to solve the problems raised in the above background technology.

[0006] In the first aspect, in order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions: Low-cost low-orbit small satellite attitude and orbit control system, including user terminal, data analysis module, orbit planning module, orbit adjustment module, attitude adjustment module, image acquisition module, database module and command center; The user terminal is used for the user or staff to input the longitude and latitude information corresponding to the image acquisition area, and send the longitude and latitude information corresponding to the image acquisition area to the data analysis module; the data analysis module is used to analyze the longitude and latitude information corresponding to the image acquisition area, and send the first preset vertex coordinate set of the image acquisition area obtained by the analysis to the orbit planning module; the orbit planning module is used to plan the standard operation orbit of the low-orbit satellite, and send the planned standard operation orbit of the low-orbit satellite to the command center; The command center sends the standard operating orbit of the low-orbit satellite to the orbit adjustment module; the image acquisition module is used to acquire images of preset coordinates on the earth's surface at fixed intervals, and send the real-time preset coordinate images at the preset coordinates to the orbit adjustment module; the orbit adjustment module is used to adjust the orbit deviation of the low-orbit satellite when the low-orbit satellite is launched and reaches the standard operating orbit; When the orbit adjustment module completes the adjustment of the low-orbit satellite, the adjustment completion information is sent to the command center, and then the command center sends the adjustment completion information to the user terminal; the command center sends the image acquisition area to the attitude adjustment module; the attitude adjustment module is used to adjust the attitude of the low-orbit satellite when it reaches the specified coordinates; The image acquisition module is also used to acquire images of the image acquisition area at preset time intervals, and save the image information of the image acquisition area to the database module, and then the command center sends the image information corresponding to the image acquisition area to the user terminal.

[0007] Furthermore, the analysis process of the data analysis module is as follows: The three-dimensional coordinate system oxyz is established with the center of the earth as the origin o, the point from the center of the earth to the intersection of the equator and the 0° meridian as the positive direction of the x-axis, the point from the center of the earth to the intersection of the equator and the 90° meridian as the positive direction of the y-axis, and the point from the center of the earth to the North Pole as the positive direction of the z-axis. Obtain the latitude and longitude information of the image acquisition area, and obtain the latitude and longitude information of the vertex corresponding to the image acquisition area according to the latitude and longitude information; Convert the vertex longitude and latitude information of the vertex corresponding to the image acquisition area into the first preset vertex coordinates: The first preset vertex coordinates of the image acquisition area are merged into a first preset vertex coordinate set.

[0008] Furthermore, the process of converting the vertex longitude and latitude information into the first preset vertex coordinates is specifically as follows: The longitude JDJi and latitude WDDi of the vertex in the longitude and longitude information of the vertex corresponding to the image acquisition area are converted into longitude radian HDJi and latitude radian HDWi through the formula. The specific formula is as follows: HDJi=JDJi×π / 180, HDWi=WDDi×π / 180, where i is the vertex number corresponding to the vertex of the image acquisition area, i=1, 2, 3, 4; Get the radius of the earth RD, and calculate the first preset vertex coordinates (xi, yi, zi) corresponding to the vertex of the image acquisition area through the formula. The specific formula is as follows: xi=RD×cos(HDJi)×cos(HDWi); yi=RD×sin(HDJi)×cos(HDWi); zi=RD×sin(HDWi).

[0009] Furthermore, the working process of the track planning module is as follows: Taking the coordinate origin of the three-dimensional coordinate system as the starting point, the coordinate origin is connected to any first preset vertex coordinate in the first preset vertex coordinate set and extended to the standard orbit of the low-orbit satellite to obtain the second preset vertex coordinate, and the second preset vertex coordinates are connected in sequence to obtain the low-orbit satellite passage area; Obtain any coordinate (xj, yj, zj) of the low-orbit satellite path area, j is the coordinate number of any coordinate of the low-orbit satellite path area, j=1, 2, ..., n, n is a positive integer, and then calculate the coordinates of the geometric center point of the low-orbit satellite path area (x0, y0, z0) by the formula. The specific formula is as follows: , , ; Calculate the orbital inclination angle corresponding to the standard orbit of the low-orbit satellite according to the coordinates of the geometric center point in the area where the low-orbit satellite passes; The standard operating orbit of the low-orbit satellite is constructed by combining the orbital inclination and orbital radius of the low-orbit satellite.

[0010] Furthermore, the calculation process of the orbital inclination is specifically as follows: Construct the position vector XL of the coordinates of the geometric center point of the low-orbit satellite path from the center of the earth, where XL=(x0, y0, z0); Connect the center of the earth and the coordinates of the geometric center point in the low-orbit satellite's path to obtain the orbital radius RG of the low-orbit satellite, and then calculate the running speed v of the low-orbit satellite in the standard orbit through the formula. The specific formula is as follows: , where G is the gravitational constant and M is the mass of the Earth; The velocity vector SD of the low-orbit satellite is calculated according to the formula. The specific formula is as follows: SD=v·(-(y0 / RG),-(x0 / RG),0).

[0011] Furthermore, the calculation process of the orbital inclination also includes: The orbital angular momentum vector DL ​​corresponding to the standard orbit of the low-orbit satellite is calculated by the formula, and the specific formula is as follows: DL=XL·SD, where · is the cross product in vector operation, and the result is not the product; where DL=(DLx,DLy,DLz), DLz is simplified to DLz=v×RG, where × is the product; The orbital inclination i corresponding to the standard operating orbit of the low-orbit satellite is calculated by the formula i=arccos(DLz / DL); wherein the orbital inclination of the low-orbit satellite is the angle formed by the orbital plane of the low-orbit satellite and the equatorial plane of the earth.

[0012] Furthermore, the adjustment process of the track adjustment module is as follows: When the low-orbit satellite reaches the standard operating orbit, the low-orbit satellite collects images of preset coordinates on the earth's surface at fixed intervals to obtain real-time preset coordinate images of the earth's surface; The real-time preset coordinate image of the earth's surface is subjected to denoising, and then the real-time preset coordinate image is cut to a resolution of 224×224 to obtain a real-time cropped preset coordinate image; The real-time cropped preset coordinate image is input into the image recognition model, and then the image recognition model outputs the actual operating altitude of the low-orbit satellite corresponding to the current time node.

[0013] Furthermore, the adjustment process of the track adjustment module includes: Obtain the standard operating altitude of the standard operating orbit of the low-orbit satellite relative to the earth's surface, subtract the actual operating altitude of the low-orbit satellite at the current time node from the standard operating altitude of the low-orbit satellite and take the absolute value to obtain the orbit deviation value of the low-orbit satellite; If the orbit deviation value of the low-orbit satellite is within the deviation value range, the actual operating altitude corresponding to the low-orbit satellite at the current time node is determined to be the normal operating altitude, and no adjustment is made; If the orbit deviation value of the low-orbit satellite does not fall outside the deviation value range, the actual operating altitude of the low-orbit satellite corresponding to the current time node is determined to be an abnormal operating altitude, and the length of the earth radius RD is obtained. The speed change value BHZ required to adjust the actual operating altitude of the low-orbit satellite to the standard operating altitude is calculated by the formula. The specific formula is as follows: ; In the formula, RH0 is the distance between the low-orbit satellite and the ground.

[0014] Furthermore, the adjustment process of the posture adjustment module is as follows: A first orbital coordinate is set in the standard operating orbit of the low-orbit satellite. When the low-orbit satellite reaches the first orbital coordinate, its own attitude is obtained through a geomagnetic sensor, and then an attitude error between its own attitude and a target attitude is calculated; wherein the own attitude includes a real-time roll angle, a real-time yaw angle and a real-time pitch angle of the low-orbit satellite, and the attitude error includes a pitch error, a yaw error and a roll error; The attitude error is sent to an attitude driver, and the attitude driver adjusts the attitude of the low-orbit satellite according to the attitude error of the low-orbit satellite; The low-orbit satellite path area is obtained, and the first intersection point of the standard operating orbit of the low-orbit satellite and the low-orbit satellite path area is used as the second orbit coordinate. When the low-orbit satellite reaches the second orbit coordinate, the low-orbit satellite completes attitude adjustment, and the image acquisition device of the low-orbit satellite faces the geometric midpoint of the image acquisition area. The second intersection of the standard operating orbit of the low-orbit satellite and the area where the low-orbit satellite passes is taken as the third orbital coordinate. When the low-orbit satellite reaches the third orbital coordinate, the low-orbit satellite stops attitude adjustment until it reaches the first orbital coordinate next time.

[0015] The second aspect is the low-cost low-orbit small satellite attitude and orbit control method, the specific method is as follows: S100, inputting longitude and latitude information corresponding to an image acquisition area, and analyzing the longitude and latitude information corresponding to the image acquisition area to obtain a first preset vertex coordinate set of the image acquisition area; S200, planning a standard operating orbit of the low-orbit satellite, and obtaining the standard operating orbit of the low-orbit satellite through planning; S300, collecting real-time preset coordinate images of preset coordinates on the surface of the earth at fixed intervals, and adjusting the orbit deviation of the low-orbit satellite in combination with the real-time preset coordinate images when the low-orbit satellite is launched and reaches the standard orbit; S400, before collecting the image collection area, the low-orbit satellite adjusts its own attitude when it reaches the specified coordinates; S500, after the adjustment is completed, the image acquisition area is imaged at intervals of a preset time.

[0016] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: The present invention analyzes the latitude and longitude information corresponding to the image acquisition area, and obtains a first preset vertex coordinate set of the image acquisition area through analysis. The standard operating orbit of the low-orbit satellite is planned in combination with the first preset vertex coordinate set, and the standard operating orbit of the low-orbit satellite is planned. During actual flight, real-time preset coordinate images of preset coordinates on the surface of the earth are collected at intervals of fixed duration. The real-time preset coordinate images are combined with the standard operating orbit to adjust the orbital deviation of the low-orbit satellite when the low-orbit satellite is launched and reaches the standard operating orbit. At the same time, before collecting the image acquisition area, the low-orbit satellite adjusts its own attitude when it reaches the specified coordinates. After the orbit and attitude are adjusted, the image acquisition area is finally collected at intervals of preset duration. The present invention realizes intelligent control of the operating orbit and the attitude of the low-cost small low-orbit satellite. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0018] Figure 1 is the overall system block diagram of the present invention; Figure 2 This is an example diagram of the image acquisition area of ​​the low-orbit satellite in the present invention; Figure 3 It is a schematic diagram of the structure of the second orbital coordinates in the present invention; Figure 4 The figure is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0019] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Embodiment 1 See also Figure 1-Figure 3 As shown, the technical solution provided by the present invention is: a low-cost low-orbit small satellite attitude and orbit control system, including a user terminal, a data analysis module, an orbit planning module, an orbit adjustment module, an attitude adjustment module, an image acquisition module, a database module and a command center; The user terminal is used for the user or staff to input the longitude and latitude information corresponding to the image acquisition area, and send the longitude and latitude information corresponding to the image acquisition area to the data analysis module; the data analysis module is used to analyze the longitude and latitude information corresponding to the image acquisition area.

[0021] In this embodiment, the working process of the data analysis module is as follows: S1, take the center of the earth as the origin o, take the point from the center of the earth to the intersection of the equator and the 0° meridian as the positive direction of the x-axis, take the point from the center of the earth to the intersection of the equator and the 90° meridian as the positive direction of the y-axis, and take the point from the center of the earth to the North Pole as the positive direction of the z-axis, and establish a three-dimensional coordinate system oxyz; S2, obtaining the longitude and latitude information of the image acquisition area, and obtaining the longitude and latitude information of the vertex corresponding to the image acquisition area according to the longitude and latitude information; It should be specifically stated that the image acquisition region is regarded as a rectangle, and the region formed by the vertices of the image acquisition region is regarded as a plane; S3, converting the vertex longitude and latitude information of the vertex corresponding to the image acquisition area into the first preset vertex coordinates. The process of converting the vertex longitude and latitude information into the first preset vertex coordinates is as follows: S31, converting the longitude JDJi and latitude WDDi of the vertex in the longitude and latitude information of the vertex corresponding to the image acquisition area into the longitude radian HDJi and the latitude radian HDWi by a formula, the specific formula is as follows: HDJi=JDJi×π / 180, HDWi=WDDi×π / 180, where i is the vertex number corresponding to the vertex of the image acquisition area, i=1, 2, 3, 4; S32, obtaining the radius length RD of the earth, and calculating the first preset vertex coordinates (xi, yi, zi) corresponding to the vertices of the image acquisition area by a formula, the specific formula is as follows: xi=RD×cos(HDJi)×cos(HDWi); yi=RD×sin(HDJi)×cos(HDWi); zi = RD × sin (HDWi); S4, merging the first preset vertex coordinates of the image acquisition area into a first preset vertex coordinate set, and then saving the image acquisition area and the first preset vertex coordinate set to a database module; The data analysis module sends the first preset vertex coordinate set of the image acquisition area to the track planning module.

[0022] In this embodiment, the orbit planning module is used to plan the standard operating orbit of the low-orbit satellite, and the working process is as follows: P1, taking the origin of the three-dimensional coordinate system as the starting point, the origin of the coordinate system is connected to any first preset vertex coordinate in the first preset vertex coordinate set and extended to the standard orbit of the low-orbit satellite to obtain the second preset vertex coordinate, and the second preset vertex coordinates are connected in sequence to obtain the low-orbit satellite passage area; P2, obtain any coordinate (xj, yj, zj) of the low-orbit satellite path area, j is the coordinate number of any coordinate in the low-orbit satellite path area, j=1, 2, ..., n, n is a positive integer, and then calculate the coordinates of the geometric center point of the low-orbit satellite path area (x0, y0, z0) by the formula. The specific formula is as follows: , , ; P3, calculates the orbital inclination corresponding to the standard orbit of the low-orbit satellite based on the coordinates of the geometric center point in the area where the low-orbit satellite passes; In this embodiment, P3 includes the following sub-steps: P31, construct the position vector XL from the center of the earth to the geometric center point coordinates of the low-orbit satellite path area, where XL=(x0, y0, z0); P32, connect the center of the earth and the coordinates of the geometric center point in the low-orbit satellite's path area to obtain the orbital radius RG of the low-orbit satellite, and then calculate the running speed v of the low-orbit satellite in the standard orbit through the formula. The specific formula is as follows: , where G is the gravitational constant and M is the mass of the Earth; P33, the velocity vector SD of the low-orbit satellite is calculated according to the formula, the specific formula is as follows: SD=v·(-(y0 / RG),-(x0 / RG),0); It should be specifically noted that, in this embodiment, the standard orbit of the low-orbit satellite is regarded as a circular orbit; P34, the orbital angular momentum vector DL ​​corresponding to the standard orbit of the low-orbit satellite is calculated by the formula, the specific formula is as follows: DL=XL·SD, where · is the cross product in vector operation, and the result is not the product; Further, DL=(DLx, DLy, DLz), where DLz is simplified to DLz=v×RG; Specifically, in DLz = v × RG, × is the product; P35, the orbital inclination i corresponding to the standard orbit of the low-orbit satellite is calculated by the formula i=arccos(DLz / DL); It should be specifically explained that the orbital inclination of a low-orbit satellite is the angle formed by the orbital plane of the low-orbit satellite and the equatorial plane of the earth.

[0023] P4, constructing a standard operating orbit of the low-orbit satellite according to the orbital inclination and orbital radius of the low-orbit satellite; The orbit planning module sends the constructed standard operating orbit of the low-orbit satellite to the command center, and the command center sends the standard operating orbit of the low-orbit satellite to the orbit adjustment module.

[0024] In this embodiment, the track adjustment module is connected to an image acquisition module, which is used to acquire images of preset coordinates on the surface of the earth at fixed intervals, and send real-time preset coordinate images at the preset coordinates to the track adjustment module; like Figure 3 As shown, the orbit adjustment module is used to adjust the orbit deviation of the low-orbit satellite when the low-orbit satellite is launched and reaches the standard operating orbit. The adjustment process is as follows: R1, when the low-orbit satellite reaches the standard operating orbit, the low-orbit satellite collects images of the preset coordinates on the earth's surface at fixed intervals to obtain real-time preset coordinate images of the earth's surface; It should be specifically noted that the preset coordinates are specifically preset coordinates on the earth's surface with high recognition; R2, denoising the real-time preset coordinate image of the earth's surface, and then converting the real-time preset coordinate image to a resolution of 224×224 to obtain a real-time cropped preset coordinate image; R3, input the real-time cropped preset coordinate image into the image recognition model, and then the image recognition model outputs the actual operating altitude of the low-orbit satellite corresponding to the current time node; Specifically, the image recognition model performs image recognition on the real-time cropped preset coordinate image, and then compares it with the historical preset coordinate image of the same earth surface taken by the existing low-orbit satellite in the standard orbit, and calculates the actual operating height of the low-orbit satellite corresponding to the current time node according to the ratio between the real-time preset coordinate image and the historical preset coordinate image; It should be specifically noted that the image recognition model used in this embodiment is a trained deep learning model, and the image recognition model is trained using the annotated real-time cropped preset coordinate image; R4, obtain the standard operating altitude of the low-orbit satellite's standard operating orbit relative to the earth's surface and the actual operating altitude of the low-orbit satellite at the current time node, subtract the actual operating altitude of the low-orbit satellite at the current time node from the standard operating altitude of the low-orbit satellite and take the absolute value to obtain the orbit deviation value of the low-orbit satellite; If the orbit deviation value of the low-orbit satellite is within the deviation value range, the actual operating altitude corresponding to the low-orbit satellite at the current time node is determined to be the normal operating altitude, and no adjustment is made at this time; If the orbit deviation value of the low-orbit satellite does not fall outside the deviation value range, it is determined that the actual operating altitude corresponding to the low-orbit satellite at the current time node is an abnormal operating altitude, and the next step is entered; R5, obtain the length of the earth radius RD, and calculate the speed change value BHZ required to adjust the actual operating altitude of the low-orbit satellite to the standard operating altitude through the formula. The specific formula is as follows: ; In the formula, RH0 is the distance between the low-orbit satellite and the ground, and RD+RH0 is the actual operating altitude of the low-orbit satellite.

[0025] When the orbit adjustment module completes the adjustment of the low-orbit satellite, the adjustment completion information is sent to the command center, and then the command center sends the adjustment completion information to the user terminal; the command center sends the image acquisition area to the attitude adjustment module; like Figure 3 As shown, the attitude adjustment module is used to adjust the attitude of the low-orbit satellite when it reaches the specified coordinates. The adjustment process is as follows: Q1, set the first orbital coordinates in the standard orbit of the low-orbit satellite. When the low-orbit satellite reaches the first orbital coordinates, it obtains its own attitude through the geomagnetic sensor, and then calculates the attitude error between its own attitude and the target attitude; Specifically, the self-attitude includes the real-time roll angle, real-time yaw angle and real-time pitch angle of the low-orbit satellite, and the attitude error includes the pitch error, yaw error and roll error; Q2, sending the attitude error to the attitude driver, which adjusts the attitude of the low-orbit satellite according to the attitude error of the low-orbit satellite; Q3, obtain the low-orbit satellite path area, and use the first intersection point of the low-orbit satellite's standard orbit and the low-orbit satellite path area as the second orbit coordinate. When the low-orbit satellite reaches the second orbit coordinate, the low-orbit satellite completes attitude adjustment. At this time, the image acquisition device of the low-orbit satellite faces the geometric midpoint of the image acquisition area. It should be specifically noted that in the prior art, the attitude of the low-orbit satellite is obtained through a geomagnetic sensor; Q4, the second intersection of the standard operating orbit of the low-orbit satellite and the area where the low-orbit satellite passes is taken as the third orbital coordinate. When the low-orbit satellite reaches the third orbital coordinate, the low-orbit satellite stops attitude adjustment until it reaches the first orbital coordinate next time.

[0026] It should be specifically stated that when the low-orbit satellite is between the second orbital coordinate and the third orbital coordinate, the image acquisition device of the low-orbit satellite is always oriented toward the geometric midpoint of the image acquisition area; The image acquisition module is used to acquire images of the image acquisition area at preset time intervals, and save the image information of the image acquisition area to the database module, and then the command center sends the image information corresponding to the image acquisition area to the user terminal.

[0027] In the present invention, if corresponding calculation formulas appear, the above calculation formulas are all dimensionless and take their numerical calculations. The weight coefficients, proportional coefficients and other coefficients in the formulas are set to a result value obtained by quantifying each parameter. The size of the weight coefficients and proportional coefficients can be determined as long as they do not affect the proportional relationship between the parameters and the result values.

[0028] Embodiment 2 like Figure 4 As shown, based on another concept of the same invention, a low-cost low-orbit small satellite attitude and orbit control method is now proposed, comprising the following steps: S100, inputting longitude and latitude information corresponding to an image acquisition area, and analyzing the longitude and latitude information corresponding to the image acquisition area to obtain a first preset vertex coordinate set of the image acquisition area; S200, planning a standard operating orbit of the low-orbit satellite, and obtaining the standard operating orbit of the low-orbit satellite through planning; S300, collecting real-time preset coordinate images of preset coordinates on the surface of the earth at fixed intervals, and adjusting the orbit deviation of the low-orbit satellite in combination with the real-time preset coordinate images when the low-orbit satellite is launched and reaches the standard orbit; S400, before collecting the image collection area, the low-orbit satellite adjusts its own attitude when it reaches the specified coordinates; S500, after the adjustment is completed, the image acquisition area is imaged at intervals of a preset time.

[0029] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. Low-cost low-orbit small satellite attitude and orbit control system, characterized by: It includes user terminal, data analysis module, track planning module, track adjustment module, attitude adjustment module, image acquisition module, database module and command center; The user terminal is used for a user or staff to input the longitude and latitude information corresponding to the image acquisition area, and send the longitude and latitude information corresponding to the image acquisition area to the data analysis module; The data analysis module is used to analyze the longitude and latitude information corresponding to the image acquisition area, and send the first preset vertex coordinate set of the image acquisition area obtained by the analysis to the track planning module; The orbit planning module is used to plan the standard operating orbit of the low-orbit satellite, and the planned standard operating orbit of the low-orbit satellite is sent to the command center; The command center sends the standard operating orbit of the low-orbit satellite to the orbit adjustment module; The image acquisition module is used to acquire images of preset coordinates on the surface of the earth at fixed time intervals, and send the real-time preset coordinate images at the preset coordinates to the orbit adjustment module; The orbit adjustment module is used to adjust the orbit deviation of the low-orbit satellite when the low-orbit satellite is launched and reaches the standard operating orbit; When the orbit adjustment module completes the adjustment of the low-orbit satellite, the adjustment completion information is sent to the command center, and then the command center sends the adjustment completion information to the user terminal; The command center sends the image acquisition area to the posture adjustment module; The attitude adjustment module is used to adjust the attitude of the low-orbit satellite when it reaches the specified coordinates; The image acquisition module is also used to acquire images of the image acquisition area at preset time intervals, and save the image information of the image acquisition area to the database module, and then the command center sends the image information corresponding to the image acquisition area to the user terminal.

2. The low-cost low-orbit small satellite attitude and orbit control system according to claim 1, characterized in that: The analysis process of the data analysis module is as follows: The three-dimensional coordinate system oxyz is established with the center of the earth as the origin o, the point from the center of the earth to the intersection of the equator and the 0° meridian as the positive direction of the x-axis, the point from the center of the earth to the intersection of the equator and the 90° meridian as the positive direction of the y-axis, and the point from the center of the earth to the North Pole as the positive direction of the z-axis. Obtain the latitude and longitude information of the image acquisition area, and obtain the latitude and longitude information of the vertex corresponding to the image acquisition area according to the latitude and longitude information; Convert the vertex longitude and latitude information of the vertex corresponding to the image acquisition area into the first preset vertex coordinates: The first preset vertex coordinates of the image acquisition area are merged into a first preset vertex coordinate set.

3. The low-cost low-orbit small satellite attitude and orbit control system according to claim 2, characterized in that: The process of converting the vertex longitude and latitude information into the first preset vertex coordinates is specifically as follows: The longitude JDJi and latitude WDDi of the vertex in the longitude and longitude information of the vertex corresponding to the image acquisition area are converted into longitude radian HDJi and latitude radian HDWi through the formula. The specific formula is as follows: HDJi=JDJi×π / 180, HDWi=WDDi×π / 180, where i is the vertex number corresponding to the vertex of the image acquisition area, i=1, 2, 3, 4; Get the radius of the earth RD, and calculate the first preset vertex coordinates (xi, yi, zi) corresponding to the vertex of the image acquisition area through the formula. The specific formula is as follows: xi=RD×cos(HDJi)×cos(HDWi); yi=RD×sin(HDJi)×cos(HDWi); zi=RD×sin(HDWi).

4. The low-cost low-orbit small satellite attitude and orbit control system according to claim 3, characterized in that: The working process of the track planning module is as follows: Taking the coordinate origin of the three-dimensional coordinate system as the starting point, the coordinate origin is connected to any first preset vertex coordinate in the first preset vertex coordinate set and extended to the standard orbit of the low-orbit satellite to obtain the second preset vertex coordinate, and the second preset vertex coordinates are connected in sequence to obtain the low-orbit satellite passage area; Obtain any coordinate (xj, yj, zj) of the low-orbit satellite path area, j is the coordinate number of any coordinate of the low-orbit satellite path area, j=1, 2, ..., n, n is a positive integer, and then calculate the coordinates of the geometric center point of the low-orbit satellite path area (x0, y0, z0) by the formula. The specific formula is as follows: ， ， ； Calculate the orbital inclination angle corresponding to the standard orbit of the low-orbit satellite according to the coordinates of the geometric center point in the area where the low-orbit satellite passes; The standard operating orbit of the low-orbit satellite is constructed by combining the orbital inclination and orbital radius of the low-orbit satellite.

5. The low-cost low-orbit small satellite attitude and orbit control system according to claim 4, characterized in that: The calculation process of the orbital inclination is specifically as follows: Construct the position vector XL of the coordinates of the geometric center point of the low-orbit satellite path from the center of the earth, where XL=(x0, y0, z0); Connect the center of the earth and the coordinates of the geometric center point in the low-orbit satellite's path to obtain the orbital radius RG of the low-orbit satellite, and then calculate the running speed v of the low-orbit satellite in the standard orbit through the formula. The specific formula is as follows: , where G is the gravitational constant and M is the mass of the Earth; The velocity vector SD of the low-orbit satellite is calculated according to the formula. The specific formula is as follows: SD=v·(-(y0 / RG),-(x0 / RG),0).

6. The low-cost low-orbit small satellite attitude and orbit control system according to claim 5, characterized in that: The calculation process of the orbital inclination also includes: The orbital angular momentum vector DL ​​corresponding to the standard orbit of the low-orbit satellite is calculated by the formula, and the specific formula is as follows: DL=XL·SD, where · is the cross product in vector operations; where DL=(DLx,DLy,DLz), DLz is simplified to DLz=v×RG, where × is the product; The orbital inclination i corresponding to the standard operating orbit of the low-orbit satellite is calculated by the formula i=arccos(DLz / DL); wherein the orbital inclination of the low-orbit satellite is the angle formed by the orbital plane of the low-orbit satellite and the equatorial plane of the earth.

7. The low-cost low-orbit small satellite attitude and orbit control system according to claim 4, characterized in that: The adjustment process of the track adjustment module is as follows: When the low-orbit satellite reaches the standard operating orbit, the low-orbit satellite collects images of preset coordinates on the earth's surface at fixed intervals to obtain real-time preset coordinate images of the earth's surface; The real-time preset coordinate image of the earth's surface is subjected to denoising, and then the real-time preset coordinate image is cut to a resolution of 224×224 to obtain a real-time cropped preset coordinate image; The real-time cropped preset coordinate image is input into the image recognition model, and then the image recognition model outputs the actual operating altitude of the low-orbit satellite corresponding to the current time node.

8. The low-cost low-orbit small satellite attitude and orbit control system according to claim 7, characterized in that: The adjustment process of the track adjustment module includes: Obtain the standard operating altitude of the standard operating orbit of the low-orbit satellite relative to the earth's surface, subtract the actual operating altitude of the low-orbit satellite at the current time node from the standard operating altitude of the low-orbit satellite and take the absolute value to obtain the orbit deviation value of the low-orbit satellite; If the orbit deviation value of the low-orbit satellite is within the deviation value range, the actual operating altitude corresponding to the low-orbit satellite at the current time node is determined to be the normal operating altitude, and no adjustment is made; If the orbit deviation value of the low-orbit satellite does not fall outside the deviation value range, the actual operating altitude of the low-orbit satellite corresponding to the current time node is determined to be an abnormal operating altitude, and the length of the earth radius RD is obtained. The speed change value BHZ required to adjust the actual operating altitude of the low-orbit satellite to the standard operating altitude is calculated by the formula. The specific formula is as follows: ; In the formula, RH0 is the distance between the low-orbit satellite and the ground.

9. The low-cost low-orbit small satellite attitude and orbit control system according to claim 8, characterized in that: The adjustment process of the posture adjustment module is as follows: A first orbital coordinate is set in the standard operating orbit of the low-orbit satellite. When the low-orbit satellite reaches the first orbital coordinate, its own attitude is obtained through a geomagnetic sensor, and then an attitude error between its own attitude and a target attitude is calculated; wherein the own attitude includes a real-time roll angle, a real-time yaw angle and a real-time pitch angle of the low-orbit satellite, and the attitude error includes a pitch error, a yaw error and a roll error; The attitude error is sent to an attitude driver, and the attitude driver adjusts the attitude of the low-orbit satellite according to the attitude error of the low-orbit satellite; The low-orbit satellite path area is obtained, and the first intersection point of the standard operating orbit of the low-orbit satellite and the low-orbit satellite path area is used as the second orbit coordinate. When the low-orbit satellite reaches the second orbit coordinate, the low-orbit satellite completes attitude adjustment, and the image acquisition device of the low-orbit satellite faces the geometric midpoint of the image acquisition area. The second intersection of the standard operating orbit of the low-orbit satellite and the area where the low-orbit satellite passes is taken as the third orbital coordinate. When the low-orbit satellite reaches the third orbital coordinate, the low-orbit satellite stops attitude adjustment until it reaches the first orbital coordinate next time.

10. A low-cost low-orbit small satellite attitude and orbit control method, characterized in that: Based on the low-cost low-orbit small satellite attitude and orbit control system according to any one of claims 1 to 9, the method is specifically as follows: S100, inputting longitude and latitude information corresponding to an image acquisition area, and analyzing the longitude and latitude information corresponding to the image acquisition area to obtain a first preset vertex coordinate set of the image acquisition area; S200, planning a standard operating orbit of the low-orbit satellite, and obtaining the standard operating orbit of the low-orbit satellite through planning; S300, collecting real-time preset coordinate images of preset coordinates on the surface of the earth at fixed intervals, and adjusting the orbit deviation of the low-orbit satellite in combination with the real-time preset coordinate images when the low-orbit satellite is launched and reaches the standard orbit; S400, before collecting the image collection area, the low-orbit satellite adjusts its own attitude when it reaches the specified coordinates; S500, after the adjustment is completed, the image acquisition area is imaged at intervals of a preset time.

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