Method, system, satellite and device for fusion processing of star sensor measurement data

Abstract

The present invention discloses a method, a system, a satellite and a device for fusing and processing star sensor measurement data, which relates to the technical field of satellite attitude determination. The method includes: obtaining a validity judgment result of the data measured by each star sensor according to the validity flag in the data measured by each star sensor configured on the satellite, the occlusion relationship between different positions where SADA moves and each star sensor, sunlight interference and lunar reflected light; and determining the data for determining the satellite attitude from the data measured by each star sensor based on all the validity judgment results. The present invention can reliably and effectively judge the validity of the data measured by the star sensor, reduce misjudgment, provide reliable and high-precision star sensor data for the determination of the satellite attitude, and has strong operability in engineering implementation.

Description

Background Art

[0002] Low Earth orbit (LEO) satellites are relatively close to the Earth's surface and have advantages such as high bandwidth, low latency, and low path loss, enabling a richer range of application scenarios. The construction of a LEO communication satellite network is a prerequisite for providing more cost-effective and popular mobile satellite communication services. In recent years, the use of large LEO communication satellite constellations to provide broadband access services globally has received extensive attention. With the gradual maturity of LEO satellites led by Starlink, satellite communication with wide coverage, high speed, and universality is expected to lead the next revolution in human communication methods. Currently, several LEO communication constellations similar to Starlink are being built both at home and abroad.

[0003] A star sensor is an optoelectronic measuring instrument based on the principle of computer vision. The directly measured physical quantity is the centroid of the nearly circular light spot formed by a star on the photodetector through an optical system. After steps such as star point extraction, star map matching, and attitude calculation, the inertial frame attitude quaternion required by the satellite's attitude and orbit control system is finally obtained.

[0004] Star sensors have advantages such as high pointing accuracy, strong autonomy, and no attitude accumulation error. In the current field of satellite attitude determination, the "star sensor + gyroscope" is the most commonly used high-precision attitude determination scheme.

[0005] As an optical sensor, stray light is an important factor affecting the sensitivity of a star sensor. The interference of stray light may reduce the contrast and modulation transfer function of the star sensor's image plane, reducing the levels of the entire image plane and deteriorating the clarity. In severe cases, the target image or signal may even be completely submerged by stray light noise, causing the star sensor to malfunction.

[0006] The stray light of a star sensor includes external stray light and internal stray light. The former refers to sunlight, earth atmosphere light, reflected light from the satellite surface and satellite equipment, etc. The latter is mainly generated by the optical system itself due to changes in temperature and other aspects. LEO communication satellites usually carry solar panels with two-axis drive to face the sun. During the rotation of the solar panels, specific positions will block the star sensor's field of view to varying degrees, resulting in invalid star measurement data.

[0007] The satellite's attitude and orbit control system uses the measurement information of star sensors and gyroscopes, and through a combined filter, achieves high-precision attitude determination. During the attitude determination process, the validity of the star sensor measurement data is first judged, and when the data is invalid, gyro data is used for attitude recursion.

[0008] The judgment result of the data validity of star sensors is extremely important for attitude determination. Low-Earth-orbit communication satellites are often equipped with multiple star sensors for attitude determination. Each star sensor's output data will carry a data validity flag. However, in actual use, stray light and the limitations of the internal data processing algorithms of star sensors often lead to misjudgments of data validity. At present, there is little research and engineering implementation on the method of accurately judging the data validity of star sensors and the data fusion processing of star sensors based on the comprehensive judgment results by considering multiple factors such as orbital information, the layout of star sensors on the satellite body, the occlusion of star sensors by moving parts of the satellite body, sunlight interference, and lunar reflected light in real-time by on-board attitude determination software. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to provide a method, system, satellite, and device for fusing and processing the measurement data of star sensors in view of the deficiencies of the prior art, specifically as follows:

[0010] 1) In the first aspect, the present invention provides a method for fusing and processing the measurement data of star sensors, and the specific technical solution is as follows:

[0011] According to the validity flag in the data measured by each star sensor configured on the satellite, obtain the first validity judgment result of the data measured by each star sensor. According to the occlusion relationship between the different positions where SADA moves and each star sensor, obtain the second validity judgment result of the data measured by each star sensor. According to sunlight interference, obtain the third validity judgment result of the data measured by each star sensor. According to lunar reflected light, obtain the fourth validity judgment result of the data measured by each star sensor;

[0012] Integrate all the first validity judgment results, all the second validity judgment results, all the third validity judgment results, and all the fourth validity judgment results to obtain the validity judgment result of the data measured by each star sensor;

[0013] Based on all the validity judgment results, determine the data used for determining the satellite attitude from the data measured by each star sensor.

[0014] The beneficial effects of a method for fusing and processing the measurement data of star sensors provided by the present invention are as follows:

[0015] It can accurately eliminate the influence of the rotation and occlusion of solar panels, sunlight interference, and lunar reflected light on the data validity of star sensors, reliably and effectively judge the data validity of star sensors, reduce misjudgments, provide reliable and high-precision star sensor data for satellite attitude determination, and has strong operability in engineering implementation, especially suitable for satellites with complex star sensor occlusion conditions.

[0016] 2) Second aspect, the present invention further provides a fusion processing system for star sensor measurement data, and the specific technical solution is as follows:

[0017] It includes a validity judgment module, a comprehensive validity judgment result module, and a data determination module;

[0018] The validity judgment module is used to: obtain the first validity judgment result of the data measured by each star sensor according to the validity flag in the data measured by each star sensor configured on the satellite, obtain the second validity judgment result of the data measured by each star sensor according to the occlusion relationship between the different positions where SADA moves and each star sensor, obtain the third validity judgment result of the data measured by each star sensor according to sunlight interference, and obtain the fourth validity judgment result of the data measured by each star sensor according to lunar reflected light;

[0019] The comprehensive validity judgment result module is used to: comprehensively combine all the first validity judgment results, all the second validity judgment results, all the third validity judgment results, and all the fourth validity judgment results to obtain the validity judgment result of the data measured by each star sensor;

[0020] The data determination module is used to: based on all the validity judgment results, determine the data for determining the satellite attitude from the data measured by each star sensor.

[0021] 3) Third aspect, the present invention further provides a satellite, including an on-board processor, and the on-board processor is used to execute any one of the above-mentioned fusion processing methods for star sensor measurement data.

[0022] 4) Fourth aspect, the present invention further provides an electronic device, the electronic device includes a processor, the processor is coupled to a memory, and at least one computer program is stored in the memory, and at least one computer program is loaded and executed by the processor so that the electronic device implements any one of the above-mentioned fusion processing methods for star sensor measurement data.

[0023] 5) Fifth aspect, the present invention further provides a computer-readable storage medium, and at least one computer program is stored in the computer-readable storage medium, and at least one computer program is loaded and executed by the processor so that the computer implements any one of the above-mentioned fusion processing methods for star sensor measurement data.

[0024] It should be noted that for the beneficial effects obtained by the technical solutions of the second to fifth aspects of the present invention and the corresponding possible implementation manners, reference can be made to the technical effects of the first aspect and its corresponding possible implementation manners described above, and details are not repeated here. Description of the Drawings

[0025] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments read in conjunction with the accompanying drawings:

[0026] Figure 1 It is a schematic flowchart of a method for fusing and processing star sensor measurement data according to an embodiment of the present invention;

[0027] Figure 2 It is a schematic diagram of the star sensor star layout scheme in the zero-position state of the sailboard deployment;

[0028] Figure 3 It is a front view schematic diagram of the optical axes of four star sensors before star layout;

[0029] Figure 4 It is a right view schematic diagram of the optical axes of four star sensors before star layout;

[0030] Figure 5 It is a top view schematic diagram of the optical axes of four star sensors before star layout;

[0031] Figure 6 It is a schematic diagram of obtaining the validity judgment result of the star sensor measurement data of the star body by integrating the data validity flag of the star sensor itself, the occlusion of the star sensor by the SADA movement, the sunlight interference, and the influence of the lunar reflected light on the star sensor;

[0032] Figure 7 It is a schematic diagram of the visibility analysis of the moon and the satellite;

[0033] Figure 8 It is a schematic structural diagram of a system for fusing and processing star sensor measurement data according to an embodiment of the present invention;

[0034] Figure 9 It is a schematic structural diagram of an electronic device according to an embodiment of the present invention. Specific Embodiments

[0035] 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 in conjunction with the accompanying drawings.

[0036] As Figure 1 shown, a method for fusing and processing star sensor measurement data according to an embodiment of the present invention includes the following steps:

[0037] S1. Obtain the first validity judgment result of the data measured by each star sensor according to the validity flag in the data measured by each star sensor configured on the satellite. Obtain the second validity judgment result of the data measured by each star sensor according to the occlusion relationship between the different positions where SADA moves and each star sensor. Obtain the third validity judgment result of the data measured by each star sensor according to sunlight interference. Obtain the fourth validity judgment result of the data measured by each star sensor according to lunar reflected light.

[0038] S2. Synthesize all the first validity judgment results, all the second validity judgment results, all the third validity judgment results, and all the fourth validity judgment results to obtain the validity judgment result of the data measured by each star sensor.

[0039] S3. Based on all the validity judgment results, determine the data used for determining the satellite attitude from the data measured by each star sensor.

[0040] Optionally, in the above technical solution, the process of obtaining the occlusion relationship between the different positions where SADA moves and each star sensor includes:

[0041] After completing the layout of multiple star sensors, determine the occlusion relationship between the different positions where SADA moves and each star sensor based on the dual-axis movement characteristics of SADA.

[0042] Optionally, in the above technical solution, the process of laying out multiple star sensors includes:

[0043] Determine the layout positions of multiple star sensors based on the satellite orbit, earth atmosphere light, solar panels, and the field of view of the star sensors.

[0044] Optionally, in S1, obtaining the third validity judgment result of the data measured by each star sensor according to sunlight interference includes:

[0045] Obtain the third validity judgment result of the data measured by each star sensor based on the satellite orbit, attitude information, and solar movement information.

[0046] Optionally, in S1, obtaining the fourth validity judgment result of the data measured by each star sensor according to lunar reflected light includes:

[0047] Obtain the fourth validity judgment result of the data measured by each star sensor based on the satellite orbit, attitude information, and lunar movement information.

[0048] Optionally, the satellite is: a low-earth orbit communication satellite with a lifting solar wing.

[0049] The present invention is illustrated through the following embodiments, specifically including:

[0050] S10. Determine the layout positions of multiple star sensors based on the satellite orbit, earth - atmosphere light, solar panels, and the fields of view of the star sensors.

[0051] Comprehensively consider the satellite orbit, earth - atmosphere light, solar panels, the fields of view of the star sensors, etc. to determine the layout of the star sensors on the satellite body. The satellite is equipped with 4 star sensors. The layout scheme of the star sensors on the satellite body in the state where the solar panels are fully deployed at zero position is as Figure 2 shown. Specifically:

[0052] There are three rotating mechanisms arranged in sequence on the satellite. The rotation axis of the middle rotating mechanism is perpendicular to the rotation axes of the two rotating mechanisms on both sides. Each of the two rotating mechanisms on both sides is connected to a solar panel, and a sun sensor is arranged on each solar panel.

[0053] According to the deployment state of the solar panels of the satellite, a rotating mechanism is configured for each solar panel. The satellite includes two solar panels, denoted as the first solar panel and the second solar panel respectively. The rotating mechanism configured for the first solar panel is denoted as B1, and the rotating mechanism configured for the second solar panel is denoted as B2. A rotating mechanism is arranged between B1 and B2, denoted as A. B1, A, and B2 are arranged in sequence. Figure 2 The cube in [[ ]] is used to represent the satellite body. The satellite body is: the remaining part of the satellite excluding the solar panels and the structures connecting the solar panels. Taking the centroid of the satellite body as the origin, a satellite - centroid body coordinate system O - X - Y - Z is established. When both solar panels are deployed, the normal line of the solar cell of the solar panel is consistent with the negative direction of the Z - axis of the satellite - centroid body coordinate system. Define the position of B1 at this time as the zero - position of B1, the position of B2 at this time as the zero - position of B2, and the position of A at this time as the zero - position of A. When B1, B2, and A are all in their respective zero - positions, the positive direction of the rotation axis of B1 is consistent with the negative direction of the X - axis of the satellite - centroid body coordinate system, the positive direction of the rotation axis of B2 is consistent with the positive direction of the X - axis of the satellite - centroid body coordinate system, and the positive direction of the rotation axis of A is consistent with the positive direction of the Y - axis of the satellite - centroid body coordinate system.

[0054] Stepper motors are used inside B1, B2, and A. B1 is used to: drive the first solar panel to rotate around the rotation axis of B1 through the stepper motor. B2 is used to: drive the second solar panel to rotate around the rotation axis of B2 through the stepper motor. A is used to: drive the first solar panel and the second solar panel to rotate around the rotation axis of A simultaneously. During this process, the right - hand rule is used to determine the rotation directions of the first solar panel and the second solar panel.

[0055] Among them, the different positions that SADA moves to can be specifically understood as: the different positions that B1, B2, and A move to.

[0056] Among them, the characteristics of SADA's biaxial movement refer to: A tracks the angular velocity of the orbit, B1 and B2 track the Beta angle, and the sailboard is aligned with the solar vector through the combined movement of A, B1, and B2.

[0057] Among them, the optical axes of the four star sensors in the front view of the satellite body layout are as Figure 3 shown, the optical axes of the four star sensors in the right view of the satellite body layout are as Figure 4 shown, and the optical axes of the four star sensors in the top view of the satellite body layout are as Figure 5 shown. It should be noted that the performance index parameters of the four star sensors are the same, and the performance index parameters are as follows: measurement accuracy, time scale accuracy, field of view, dynamic performance, all-sky recognition time, startup time, solar suppression angle, earth suppression angle, data update rate, data availability, etc.

[0058] The four star sensors are respectively denoted as the first star sensor, the second star sensor, the third star sensor, and the fourth star sensor. The optical axis of the first star sensor is denoted as G1, the optical axis of the second star sensor is denoted as G2, the optical axis of the third star sensor is denoted as G3, and the optical axis of the fourth star sensor is denoted as G4. Then the following discussion is carried out:

[0059] 1) Figure 3 In, the angle between G1 and the negative Z-axis direction of the satellite centroid body coordinate system is equal to the angle between G3 and the negative Z-axis direction of the satellite centroid body coordinate system, and both are denoted as θ1. Among them, represents: taking the arcsine of using the arcsine function, the unit is degree, R e is the radius of the earth, the unit is Km, α is the earth suppression angle of the star sensor, the unit is degree, h is the satellite orbit height, the unit is Km, λ is the field of view represented by the half-cone angle of the star sensor, the unit is degree; h0 is the height of the earth's atmosphere light, and the typical value range of h0 can be 100 ≤ h0 ≤ 150, the unit is Km.

[0060] 2) As Figure 4 shown, the angle between G2 and the negative Z-axis direction of the satellite centroid body coordinate system is equal to the angle between G4 and the negative Z-axis direction of the satellite centroid body coordinate system, and both are denoted as θ2. Among them, represents: taking the arcsine of using the arcsine function, the unit is degree, R eR is the radius of the earth, in km; α is the earth suppression angle of the star sensor, in degrees; h is the satellite orbit altitude, in km; λ is the field of view represented by the half cone angle of the star sensor, in degrees; h0 is the height of the earth - atmosphere light, and the typical value range of h0 can be 100 ≤ h0 ≤ 150, in km.

[0061] Moreover, when arranging the star sensors, the following conditions also need to be met:

[0062] 1) By setting h0, ensure that when the satellite operates in the earth - oriented attitude, the earth - atmosphere light has no influence on the star sensor;

[0063] 2) Keep a certain angle between the optical axes of every two star sensors;

[0064] 3) Ensure that when the solar panel moves to some positions, the fields of view of at least two star sensors are not affected.

[0065] S11. After completing the layout of multiple star sensors, based on the dual - axis motion characteristics of SADA, determine the occlusion relationship between the different positions that SADA moves to and each star sensor:

[0066] In 3D modeling software such as SolidWorks or Pro - e, perform different discrete - angle motions of B1, A, and B2 in SADA in the 3D model of the satellite body according to the control characteristics of SADA, and observe the occlusion situations of the first star sensor, the second star sensor, the third star sensor, and the fourth star sensor. Record the angular positions of B1, A, and B2 in SADA and the occlusion situations of the first star sensor, the second star sensor, the third star sensor, and the fourth star sensor, and form an index table for the corresponding relationships, as shown in Table 1. Before satellite launch, the on - board software pre - stores this index table according to the launch time, and after in - orbit operation, it can be updated regularly (such as once a day or at intervals of multiple days) according to the on - board storage space.

[0067] Table 1:

[0068]

[0069] S12. Synthesize the data validity flag of the star sensor itself, the occlusion relationship between the different positions that SADA moves to and each star sensor, the sunlight interference, and the influence of the lunar reflected light on the star sensor to obtain the judgment result of the data validity of the satellite - body star sensor measurement. As Figure 6 shown, specifically:

[0070] S120. Judge whether the data measured by the star sensor has been introduced in the determination of the overall satellite attitude to obtain the first judgment result. If the first judgment result is no, then execute S1201, specifically:

[0071] S1201. Query the index table of the corresponding relationship between the angular positions of A, B1, and B2 in SADA and the occlusion conditions of the first star sensor, the second star sensor, the third star sensor, and the fourth star sensor, and obtain the angular position values of A, B1, and B2 in SADA. In this value combination, at least two star sensors are not occluded. Move A, B1, and B2 in SADA to the queried angular positions.

[0072] S1202. If the measurement data of the two non-occluded star sensors are both valid for ΔT seconds continuously, then introduce the measurement data of the two non-occluded star sensors into the attitude determination algorithm; the time ΔT is a threshold, which can be determined according to the overall satellite safety strategy; denote the two non-occluded star sensors as Star1 and Star2, and the valid measurement data of Star1 and Star2 are respectively: and Q Star1 、Q Star2 The corresponding star times are T1 and T2 respectively. The star time is the time on the satellite, with the unit of s. Denote the initial power-on moment when the satellite is in orbit as the star time 0 moment.

[0073] S1203. The method of introducing the measurement data of the two non-occluded star sensors into the attitude determination algorithm is as follows: First, use the gyro output data to perform time error compensation on the measurement data of Star1 and Star2, and the supplemented measurement results are: Q' Star1 、Q' Star2 ; Unify the measurement data of Star1 and Star2 to the same moment T star (If T1≥T2, then unify to the moment T1; if T1≤T2, then unify to the moment T2), and denote the quaternion after unifying to the same moment T star as: Then use Adopt the double-vector attitude determination algorithm to obtain the star sensor attitude measurement data Q Star ,Q Star corresponding to the star time T star ,the so-called Q Star is the attitude quaternion of the satellite body system relative to the inertial system obtained by the double-vector attitude determination algorithm.

[0074] S121. If the first judgment result is yes, then execute S1210. Denote the current moment star time as T c ,and the attitude quaternions measured by the first star sensor, the second star sensor, the third star sensor, and the fourth star sensor are respectively: The star times corresponding to the measurement data of the first star sensor, the second star sensor, the third star sensor, and the fourth star sensor are: T S1 、T S2 、T S3 、T S4 , and the validity flags of their own output data are: fFlag sensor1 、fFlag sensor2 、fFlag sensor3 、fFlag sensor4 . According to the validity flags in the measurement data of each star sensor configured on the satellite, the first validity judgment result of the measurement data of each star sensor can be directly obtained.

[0075] S1210. According to the occlusion relationship between the different positions where SADA moves and each star sensor, the second validity judgment result of the measurement data of each star sensor is obtained. Specifically:

[0076] According to the angle positions of A, B1, and B2 at the current moment in SADA, query the index table of the corresponding relationship between the angle positions of the SADA drive mechanisms A, B1, and B2 and the occlusion conditions for the first star sensor, the second star sensor, the third star sensor, and the fourth star sensor, determine the occlusion relationship of the SADA current position with respect to the star sensor, and judge the validity of the star sensor data caused by the movement of SADA. Query the index table according to the angle positions of A, B1, and B2 in SADA at the current moment. If the angle positions of A, B1, and B2 in SADA at the current moment are not equal to the discrete values in the index table, then to the corresponding S m Cover k =0 (m = 1, 2, 3, 4; k = 1, 2,..., n) is approximated to the A index angle direction.

[0077] If the occlusion condition for the first star sensor is obtained as: occluded, then the validity of the star sensor data caused by the movement of SADA: f1Flag SADA =0; if the occlusion condition for the first star sensor is obtained as: unoccluded, then the validity of the measurement data of the first star sensor caused by the movement of SADA: f1Flag SADA =1.

[0078] If the occlusion condition for the second star sensor is obtained as: occluded, then the validity of the star sensor data caused by the movement of SADA: f2Flag SADA =0; if the occlusion condition for the second star sensor is obtained as: unoccluded, then the validity of the measurement data of the second star sensor caused by the movement of SADA: f2Flag SADA =1.

[0079] If the occlusion condition of the third star sensor is: occlusion, the validity of the star sensor data caused by the SADA movement: f3Flag SADA = 0; if the occlusion condition of the third star sensor is: unoccluded, the validity of the data measured by the third star sensor caused by the SADA movement: f3Flag SADA = 1.

[0080] If the occlusion condition of the fourth star sensor is: occlusion, the validity of the star sensor data caused by the SADA movement: f4Flag SADA = 0; if the occlusion condition of the fourth star sensor is: unoccluded, the validity of the data measured by the fourth star sensor caused by the SADA movement: f4Flag SADA = 1.

[0081] f i Flag SADA = 1 (i = 1, 2, 3, 4) indicates that the SADA movement has no effect on the i-th star sensor, f i Flag SADA = 0 (i = 1, 2, 3, 4) indicates that the data of the star sensor i caused by the SADA movement is invalid according to the judgment principle of the present invention.

[0082] S1211. Based on the satellite orbit, attitude information, and solar motion information, obtain the third validity judgment result of the data measured by each star sensor. Specifically:

[0083] According to the attitude of the satellite body relative to the orbital system, satellite orbit information, installation relationship of the first star sensor on the satellite body, installation relationship of the second star sensor on the satellite body, installation relationship of the third star sensor on the satellite body, and installation relationship of the fourth star sensor on the satellite body, project the orbital system solar vector onto the measurement coordinate systems of the first star sensor, the second star sensor, the third star sensor, and the fourth star sensor; obtain the angle Ang1 between the optical axis G1 of the first star sensor and the solar vector in the measurement coordinate system of the first star sensor sun , obtain the angle Ang2 between the optical axis G2 of the second star sensor and the solar vector in the measurement coordinate system of the second star sensor sun , obtain the angle Ang3 between the optical axis G3 of the third star sensor and the solar vector in the measurement coordinate system of the third star sensor sun , obtain the angle Ang4 between the optical axis G4 of the fourth star sensor and the solar vector in the measurement coordinate system of the fourth star sensor sun .

[0084] If it is determined according to the on - satellite orbit - determined penumbra area result that the satellite is not in the penumbra area, the determination of the validity of the star sensor data caused by sunlight interference is as follows:

[0085] S12110. If Ang1 sun ≥β, then it is determined that the validity f1Flag of the data measured by the first star sensor caused by sunlight interference sun = 1; otherwise, it is determined that the validity f1Flag of the data measured by the first star sensor caused by sunlight interference sun = 0. β is the solar suppression angle of the star sensor represented by the semi - cone angle.

[0086] S12111. If Ang2 sun ≥β, then it is determined that the validity f2Flag of the data measured by the second star sensor caused by sunlight interference sun = 1; otherwise, it is determined that the validity f2Flag of the data measured by the second star sensor caused by sunlight interference sun = 0.

[0087] S1212. If Ang3 sun ≥β, then it is determined that the validity f3Flag of the data measured by the third star sensor caused by sunlight interference sun = 1; otherwise, it is determined that the validity f3Flag of the data measured by the third star sensor caused by sunlight interference sun = 0.

[0088] S1213. If Ang4 sun ≥β, then it is determined that the validity f4Flag of the data measured by the fourth star sensor caused by sunlight interference sun = 1; otherwise, it is determined that the validity f4Flag of the data measured by the fourth star sensor caused by sunlight interference sun = 0.

[0089] f i Flag sun = 1 (i = 1, 2, 3, 4) indicates that sunlight interference has no effect on the i - th star sensor, and f i Flag sun = 0 (i = 1, 2, 3, 4) indicates that according to the data validity determination principle of the present invention, sunlight interference causes the data measured by the i - th star sensor to be invalid.

[0090] If it is determined according to the on - satellite orbit - determined penumbra area result that the satellite is in the penumbra area, the determination of the validity of the star sensor data caused by sunlight interference is as follows:

[0091] f i Flag sun= 1 (i = 1, 2, 3, 4). It means that the sunlight interference has no effect on the i-th star sensor.

[0092] S122. Judge the validity of the star sensor data caused by the lunar reflected light. Specifically, based on the satellite orbit, attitude information, and lunar motion information, obtain the fourth validity judgment result of the data measured by each star sensor. The specific description is as follows:

[0093] S1220. First, judge whether the satellite cannot see the moon to obtain the second judgment result. If the judgment result is: the satellite cannot see the moon. Then the judgment result of the validity of the star sensor data caused by the lunar reflected light is: f i Flag moon = 1 (i = 1, 2, 3, 4).

[0094] Judge whether the satellite can see the moon. The specific judgment process is as follows:

[0095] As Figure 7 shown, treat the satellite and the moon as mass points. Denote the point where the satellite is tangent to the earth as P, and the included angle where: asin represents the output of the arcsine function in degrees, and R e is the radius of the earth (unit: Km), and h is the satellite orbit altitude (unit: Km).

[0096] The inertial system lunar position vector calculated according to the satellite orbit determination algorithm: R i_moon ; The satellite inertial system position vector: R i_Sat , calculate the included angle between the vector from the satellite to the moon and the vector from the satellite to the earth center as:

[0097] If ξ < η, then it is judged that the satellite cannot see the moon, and the second judgment result is: yes. If ξ ≥ η, then it is judged that the satellite can see the moon, and the second judgment result is: no.

[0098] S1221. If the second judgment result is: no, then the process of judging the validity of the star sensor data caused by the lunar reflected light is as follows:

[0099] According to the inertial system lunar position vector: R i_moon , satellite orbit information, satellite body relative orbit system attitude, installation relationship of the first star sensor on the satellite body, installation relationship of the second star sensor on the satellite body, installation relationship of the third star sensor on the satellite body, installation relationship of the fourth star sensor on the satellite body, project the orbit system solar vector onto the measurement coordinate systems of the first star sensor, the second star sensor, the third star sensor, and the fourth star sensor;

[0100] The included angle Ang1 between the optical axis G1 of the first star sensor and the lunar vector is obtained in the measurement coordinate system of the first star sensor moon , and the included angle Ang2 between the optical axis G2 of the second star sensor and the lunar vector is obtained in the measurement coordinate system of the second star sensor moon , and the included angle Ang3 between the optical axis G3 of the third star sensor and the lunar vector is obtained in the measurement coordinate system of the third star sensor moon , and the included angle Ang4 between the optical axis G4 of the fourth star sensor and the lunar vector is obtained in the measurement coordinate system of the fourth star sensor moon .

[0101] Then, the judgment of the validity of the star sensor data caused by the lunar reflected light is as follows:

[0102] If Ang1 moon ≥λ, then it is judged that the validity f1Flag of the data measured by the first star sensor caused by the interference of the lunar reflected light moon =1; otherwise, it is judged that the validity f1Flag of the data measured by the first star sensor caused by the interference of the lunar reflected light moon =0.

[0103] If Ang2 moon ≥λ, then it is judged that the validity f2Flag of the data measured by the second star sensor caused by the interference of the lunar reflected light moon =1; otherwise, it is judged that the validity f2Flag of the data measured by the second star sensor caused by the interference of the lunar reflected light moon =0.

[0104] If Ang3 moon ≥λ, then it is judged that the validity f3Flag of the data measured by the third star sensor caused by the interference of the lunar reflected light moon =1; otherwise, it is judged that the validity f3Flag of the data measured by the third star sensor caused by the interference of the lunar reflected light moon =0.

[0105] If Ang4 moon ≥λ, then it is judged that the validity f3Flag of the data measured by the fourth star sensor caused by the interference of the lunar reflected light moon =1; otherwise, it is judged that the validity f4Flag of the data measured by the fourth star sensor caused by the interference of the lunar reflected light moon =0.

[0106] f i Flag moon =1 (i = 1, 2, 3, 4) indicates that the lunar reflected light has no influence on the i-th star sensor, f i Flag moon= 0 (i = 1, 2, 3, 4) indicates that the data measured by the i-th star sensor is invalid due to the lunar reflected light according to the data validity judgment principle of the present invention.

[0107] S313. Combine all the first validity judgment results, all the second validity judgment results, all the third validity judgment results, and all the fourth validity judgment results to obtain the validity judgment result of the data measured by each star sensor. Specifically, combine the star sensor's own data validity flag, SADA, the sun, the lunar movement, and the star sensor's own data validity flag to obtain the validity judgment result of the data measured by the star sensor.

[0108] The data validity judgment result f of the i-th star sensor i Flag is:

[0109] f i Flag = fFlag sensori *f i Flag SADA *f i Flag sun *f i Flag sun *f i Flag moon

[0110] S13. Based on all the validity judgment results, determine the data used for determining the satellite attitude from the data measured by each star sensor, that is, determine the star sensor data for attitude determination based on the validity judgment results. Specifically:

[0111] S130. If f1Flag = f2Flag = f3Flag = f4Flag = 1, and the measurement data of all four star sensors are valid, then use the measurement data of the first star sensor and the measurement data of the second star sensor. First, synchronize the time using the gyro measurement data, and then perform double-vector attitude determination to obtain the double-vector attitude determination result: Use the measurement data of the first star sensor and the measurement data of the third star sensor. First, synchronize the time using the gyro measurement data, and then perform double-vector attitude determination to obtain the double-vector attitude determination result: Use the measurement data of the first star sensor and the measurement data of the fourth star sensor. First, synchronize the time using the gyro measurement data, and then perform double-vector attitude determination to obtain the double-vector attitude determination result: Use the measurement data of the second star sensor and the measurement data of the third star sensor. First, synchronize the time using the gyro measurement data, and then perform double-vector attitude determination to obtain the double-vector attitude determination result: Use the measurement data of the second star sensor and the fourth star sensor. First, synchronize the time using the gyro measurement data, and then perform double-vector attitude determination to obtain the double-vector attitude determination result: Use the measurement data of the third star sensor and the fourth star sensor. First, synchronize the time using the gyro measurement data, and then perform double-vector attitude determination to obtain the double-vector attitude determination result: From Q 12 、Q 13 、Q 14 、Q 23 、Q 24 、Q 34 , according to the 312 rotation sequence, obtain the quaternions Q 12 、Q 13 、Q 14 、Q 23 、Q 24 、Q 34 The corresponding attitude angles (unit: degree):

[0112]

[0113] Record:

[0114] Ang Star =(Ang 12 *10 6 +Ang 13 *10 6 +Ang 14 *10 6 +Ang 23 *10 6 +

[0115] Ang 24 *10 6 +Ang 34 *10 6 ) / 6

[0116] Convert Ang Star / 10 6 to the attitude quaternion Q Star according to the 312 rotation sequence. Q Star is the attitude quaternion of the body relative to the inertial system after the fusion processing of the star sensor attitude measurement data provided for attitude determination. The so-called Q 12 、Q 13 、Q 14 、Q 23 、Q 24 、Q 34 are all attitude quaternions of the satellite body system relative to the inertial system obtained by the double-vector attitude determination algorithm.

[0117] S131. If 3 out of 4 star sensors are effective, then use a method similar to S13 to first perform time synchronization between every two of them, then perform double-vector attitude determination, and finally average the double-vector attitude determination results. The average result is used as the star sensor attitude measurement data provided for attitude determination.

[0118] S132. If only 2 out of 4 star sensors are effective, then use a method similar to S13 to first perform time synchronization between the measurement data of the two star sensors, then perform double-vector attitude determination, and use the double-vector attitude determination result as the star sensor attitude measurement data provided for attitude determination.

[0119] S133. If only 1 out of 4 star sensors is effective, then use the measurement result of this star sensor as the star sensor attitude measurement data provided for attitude determination.

[0120] S134. If all 4 star sensors are ineffective, then provide the result for the attitude determination process as: star sensor ineffective, no effective measurement data.

[0121] In the above embodiments, although the steps are numbered S1, S2, etc., these are only specific embodiments given by the present invention. Those skilled in the art can adjust the execution order of S1, S2, etc. according to the actual situation, and this is also within the protection scope of the present invention. It can be understood that in some embodiments, it may include some or all of the above embodiments.

[0122] As Figure 8 shown, a fusion processing system 200 for star sensor measurement data according to an embodiment of the present invention includes a validity judgment module 201, a validity judgment result integration module 202, and a data determination module 203;

[0123] The validity judgment module 201 is configured to: obtain a first validity judgment result of the measurement data of each star sensor according to the validity flag in the measurement data of each star sensor configured on the satellite, obtain a second validity judgment result of the measurement data of each star sensor according to the occlusion relationship between the different positions where SADA moves and each star sensor, obtain a third validity judgment result of the measurement data of each star sensor according to sunlight interference, and obtain a fourth validity judgment result of the measurement data of each star sensor according to lunar reflected light;

[0124] The validity judgment result integration module 202 is configured to: integrate all the first validity judgment results, all the second validity judgment results, all the third validity judgment results, and all the fourth validity judgment results to obtain a validity judgment result of the measurement data of each star sensor;

[0125] The data determination module 203 is configured to: based on all the validity judgment results, determine the data for satellite attitude determination from the data measured by each star sensor.

[0126] Optionally, in the above technical solution, it further includes an occlusion relationship determination module, and the occlusion relationship determination module is configured to:

[0127] After the layout of multiple star sensors is completed, based on the SADA biaxial motion characteristics, determine the occlusion relationship between the different positions where SADA moves to and each star sensor.

[0128] Optionally, in the above technical solution, it further includes a layout module, and the layout module is configured to: based on the satellite orbit, solar panels, and the field of view of the star sensors, determine the layout positions of multiple star sensors.

[0129] Optionally, in the above technical solution, the validity judgment module 201 is further specifically configured to: based on the satellite orbit, earth - atmosphere light, attitude information, and solar motion information, obtain the third validity judgment result of the data measured by each star sensor.

[0130] Optionally, in the above technical solution, the validity judgment module 201 is further specifically configured to: based on the satellite orbit, attitude information, and lunar motion information, obtain the fourth validity judgment result of the data measured by each star sensor.

[0131] Optionally, in the above technical solution, the satellite is: a low - earth - orbit communication satellite with a lifting solar wing.

[0132] It should be noted that the beneficial effects of the fusion processing system 200 for star sensor measurement data provided in the above embodiments are the same as those of the above - mentioned fusion processing method for star sensor measurement data, and will not be elaborated here. In addition, when the system provided in the above embodiments realizes its functions, only the division of the above - mentioned functional modules is used for illustration. In practical applications, the above functions can be allocated to different functional modules according to needs, that is, the system can be divided into different functional modules according to the actual situation to complete all or part of the functions described above. In addition, the system and method embodiments provided in the above embodiments belong to the same concept, and the specific implementation process is detailed in the method embodiments and will not be elaborated here.

[0133] As Figure 9 shown, an electronic device 300 according to an embodiment of the present invention, the electronic device 300 includes a processor 320, the processor 320 is coupled to a memory 310, and at least one computer program 330 is stored in the memory 310. The at least one computer program 330 is loaded and executed by the processor 320 so that the electronic device 300 implements any one of the above - mentioned fusion processing methods for star sensor measurement data. Specifically:

[0134] The electronic device 300 can vary significantly due to different configurations or performances. It may include one or more processors 320 (Central Processing Units, CPUs) and one or more memories 310. Among them, at least one computer program 330 is stored in the one or more memories 310, and the at least one computer program 330 is loaded and executed by the one or more processors 320, so that the electronic device 300 can implement any one of the star sensor measurement data fusion processing methods provided in the above embodiments. Of course, the electronic device 300 may also have components such as a wired or wireless network interface, a keyboard, and an input / output interface for input and output. The electronic device 300 may further include other components for implementing the device functions, which will not be elaborated here. The electronic device may specifically be a computer or the like.

[0135] In an embodiment of the present invention, a computer-readable storage medium stores at least one computer program, and the at least one computer program is loaded and executed by a processor so that a computer can implement any one of the star sensor measurement data fusion processing methods.

[0136] Optionally, the computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a compact disc read-only memory (CD-ROM), a magnetic tape, a floppy disk, an optical data storage device, or the like.

[0137] In an exemplary embodiment, a computer program product or a computer program is further provided. The computer program product or the computer program includes computer instructions, and the computer instructions are stored in a computer-readable storage medium. The processor of the electronic device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the electronic device executes any one of the star sensor measurement data fusion processing methods.

[0138] It should be noted that the terms "first", "second", etc. in the description and claims of the present application are used to distinguish similar objects, and do not represent a specific order or sequence. Under appropriate circumstances, the order of use of similar objects may be interchanged so that the embodiments of the present application described here can be implemented in an order other than the illustrated or described order.

[0139] Those skilled in the art of the present technology know that the present invention can be implemented as a system, method, or computer program product. Therefore, the present invention can be specifically implemented in the following forms, namely: it can be completely hardware, can also be completely software (including firmware, resident software, microcode, etc.), and can also be in the form of a combination of hardware and software, which is generally referred to as "circuit", "module", or "system" in this article. In addition, in some embodiments, the present invention can also be implemented in the form of a computer program product in one or more computer-readable media, which contain computer-readable program code.

[0140] Any combination of one or more computer-readable media can be adopted. The computer-readable media can be computer-readable signal media or computer-readable storage media. The computer-readable storage media can be, for example - but not limited to - electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or components, or any combination of the above. More specific examples (non-exhaustive list) of the computer-readable storage media include: electrical connections with one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above. In the present invention, the computer-readable storage media can be any tangible medium that contains or stores a program, which can be used by or in combination with an instruction execution system, device, or component.

[0141] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limitations on the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for fusion processing of star sensor measurement data, characterized in that Including: Based on the validity flag in the data measured by each star sensor configured on the satellite, obtain the first validity judgment result of the data measured by each star sensor. According to the occlusion relationship between the different positions where SADA moves and each star sensor, obtain the second validity judgment result of the data measured by each star sensor. According to sunlight interference, obtain the third validity judgment result of the data measured by each star sensor. According to lunar reflected light, obtain the fourth validity judgment result of the data measured by each star sensor. Integrate all the first validity judgment results, all the second validity judgment results, all the third validity judgment results, and all the fourth validity judgment results to obtain the validity judgment result of the data measured by each star sensor. Based on all the validity judgment results, determine the data used for determining the satellite attitude from the data measured by each star sensor.

2. The fusion processing method for star sensor measurement data according to claim 1, wherein, The process of obtaining the occlusion relationship between the different positions where SADA moves and each star sensor includes: After completing the layout of multiple star sensors, based on the dual-axis movement characteristics of SADA, determine the occlusion relationship between the different positions where SADA moves and each star sensor.

3. A method for fusion processing of star sensor measurement data according to claim 2, characterized in that, The process of laying out multiple star sensors includes: Based on the satellite orbit, earth-atmosphere light, solar panels, and the field of view of the star sensors, determine the layout positions of multiple star sensors.

4. A method for fusing and processing star sensor measurement data according to claim 1, characterized in that, According to sunlight interference, obtaining the third validity judgment result of the data measured by each star sensor includes: Based on the satellite orbit, attitude information, and solar movement information, obtain the third validity judgment result of the data measured by each star sensor.

5. A method for fusion processing of star sensor measurement data according to claim 1, characterized in that, According to lunar reflected light, obtaining the fourth validity judgment result of the data measured by each star sensor includes: Based on the satellite orbit, attitude information, and lunar movement information, obtain the fourth validity judgment result of the data measured by each star sensor.

6. A method for fusing and processing star sensor measurement data according to any one of claims 1 to 5, characterized in that, The satellite is: a low-earth orbit communication satellite with a lifting solar wing.

7. A fusion processing system for star sensor measurement data, characterized in that, Including a validity judgment module, a validity judgment result integration module, and a data determination module; The validity judgment module is used to: based on the validity flag in the data measured by each star sensor configured on the satellite, obtain the first validity judgment result of the data measured by each star sensor. According to the occlusion relationship between the different positions where SADA moves and each star sensor, obtain the second validity judgment result of the data measured by each star sensor. According to sunlight interference, obtain the third validity judgment result of the data measured by each star sensor. According to lunar reflected light, obtain the fourth validity judgment result of the data measured by each star sensor. The validity judgment result integration module is used to: integrate all the first validity judgment results, all the second validity judgment results, all the third validity judgment results, and all the fourth validity judgment results to obtain the validity judgment result of the data measured by each star sensor. The data determination module is used to: based on all the validity judgment results, determine the data used for determining the satellite attitude from the data measured by each star sensor.

8. A satellite, characterized in that, It includes an on-board processor, and the on-board processor is used to execute a method for fusion processing of star sensor measurement data as described in any one of claims 1 to 6.

9. An electronic device, characterized in that, The electronic device includes a processor, the processor is coupled to a memory, and at least one computer program is stored in the memory. The at least one computer program is loaded and executed by the processor so that the electronic device implements a method for fusion processing of star sensor measurement data as described in any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that, At least one computer program is stored in the computer-readable storage medium, and the at least one computer program is loaded and executed by a processor so that a computer implements a method for fusion processing of star sensor measurement data as described in any one of claims 1 to 6.

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