Load autonomous moon scanning method and device based on sunlight avoidance

Abstract

The invention discloses a load autonomous moon scanning method and device based on sunlight avoidance, and belongs to the field of satellite attitude control. The method comprises the following steps: determining a moon scanning axis, a scanning angular velocity, a total scanning duration and a sunlight avoidance angle range of a satellite load according to a calibration requirement, an installation condition and a layout characteristic of the satellite load; determining a scanning center moment of the satellite load and a corresponding target attitude according to the position prediction information of the moon scanning axis and the satellite load in the future time period; according to the target attitude, the scanning angular velocity and the total scanning time length, the satellite load is subjected to scanning and sunlight avoidance recheck in the acceleration and deceleration process in sequence, and scanning and acceleration and deceleration start-stop information when the satellite load correctly completes sunlight avoidance is determined; and adjusting the motion state of the satellite load according to the scanning start-stop information, the acceleration and deceleration start-stop information and a preset maneuvering preparation moment so as to enable the satellite load to complete moon scanning. According to the invention, sunlight avoidance can be automatically completed in the moon scanning process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of satellite attitude control, in particular to a load autonomous moon scanning method and device based on sunlight avoidance. BACKGROUND

[0002] The imaging load detector of an earth observation satellite may change its radiation response characteristics in orbit, and needs on-orbit calibration. The on-orbit calibration accuracy of a satellite based on real ground targets is greatly affected by the atmospheric environment, and the use of space celestial bodies for on-orbit radiation calibration can eliminate the influence of the atmosphere. In celestial body calibration, the moon is the largest extraterrestrial target after the sun in terms of apparent angular size, and the moon's reflection characteristics are very stable and its spectrum covers all visible and near-infrared spectral bands, so it is very suitable as a reference radiation benchmark for the satellite's sun reflection channel. In order to cooperate with the load on-orbit radiation calibration, the control system is required to have the ability to quickly scan the moon.

[0003] In related technologies, the inertial scanning mode has not considered the need for sunlight avoidance, and each time before on-orbit calibration, the moon scanning strategy needs to be determined on the ground in advance, then mathematical simulation is performed, the angle between the load optical axis and the sunlight vector is reviewed during the entire process, the sunlight avoidance effect is confirmed, and the unblocked field of view of the earth during moon scanning also needs to be reviewed, which all lead to a high cost of determining the moon scanning strategy.

[0004] Therefore, there is an urgent need for a load autonomous moon scanning method and device based on sunlight avoidance to solve the above technical problems. SUMMARY

[0005] The present application provides a load autonomous moon scanning method and device based on sunlight avoidance, which can autonomously complete sunlight avoidance during moon scanning to reduce the cost of moon scanning strategy. The technical solution is as follows: On the one hand, a load autonomous moon scanning method based on sunlight avoidance is provided, the method comprising: According to the calibration requirements, installation conditions and layout characteristics of the satellite load, the moon scanning axis, scanning angular velocity, scanning total time and sunlight avoidance angle range of the satellite load are determined; According to the moon scanning axis and the position prediction information of the satellite load for the future period, the scanning center time and the target attitude of the scanning center time of the satellite load are determined; wherein the position prediction information includes the satellite orbit position vector, the sun position vector and the moon position vector; According to the target attitude, the scanning angular velocity and the scanning total time, the sunlight avoidance review of the scanning process and the acceleration / deceleration process of the satellite load is performed in turn, and the scanning start / stop information and the acceleration / deceleration start / stop information when the satellite load correctly completes the sunlight avoidance are determined; According to the scanning start-stop information, the acceleration-deceleration start-stop information and a preset maneuver preparation time, the motion state of the satellite load is adjusted, so that the satellite load completes the moon scanning.

[0006] In another aspect, a sunlight-avoiding-based load autonomous moon scanning device is provided, and the device comprises: A first determination module is configured to determine a moon scanning axis, a scanning angular velocity, a total scanning time length and a sunlight-avoiding angle range of the satellite load according to a scaling demand, an installation condition and a layout characteristic of the satellite load. A second determination module is configured to determine a scanning center time and a target attitude at the scanning center time of the satellite load according to the moon scanning axis and position prediction information of the satellite load in a future time period, wherein the position prediction information comprises a satellite orbit position vector, a sun position vector and a moon position vector. A review module is configured to review sunlight avoidance of a scanning process and an acceleration-deceleration process of the satellite load in sequence according to the target attitude, the scanning angular velocity and the total scanning time length, and to determine scanning start-stop information and acceleration-deceleration start-stop information when the satellite load correctly completes sunlight avoidance. A scanning module is configured to adjust the motion state of the satellite load according to the scanning start-stop information, the acceleration-deceleration start-stop information and a preset maneuver preparation time, so that the satellite load completes the moon scanning.

[0007] In another aspect, a computer device is provided, and the computer device comprises a memory and a processor, the memory is configured to store a computer program, and the processor is configured to execute the computer program stored in the memory to realize the steps of the sunlight-avoiding-based load autonomous moon scanning method.

[0008] In another aspect, a computer readable storage medium is provided, and the storage medium stores a computer program, and the computer program is executed by a processor to realize the steps of the sunlight-avoiding-based load autonomous moon scanning method.

[0009] In another aspect, a computer program product is provided, and the computer program product comprises a computer program, and the computer program is executed by a processor to realize the steps of the sunlight-avoiding-based load autonomous moon scanning method.

[0010] The technical solution provided by this invention can bring at least the following beneficial effects: Based on the payload calibration requirements and installation conditions, the lunar scanning axis, scanning angular velocity, and total scanning time are determined in advance, and the sunlight avoidance angle range is determined based on the payload layout and characteristics. Then, based on the predicted information of the satellite payload, its scanning center time and corresponding target attitude are determined, and the sunlight avoidance during the scanning process and acceleration / deceleration process is verified based on the scanning center time to determine the correct start and stop times and corresponding attitude quaternions for sunlight avoidance. Finally, the operating state of the satellite payload is adjusted based on these start and stop times and attitude quaternions to complete the lunar scan. This method designs an autonomous sunlight avoidance strategy based on the motion characteristics of the satellite, the sun, and the moon, ensuring payload safety during the lunar scan process. Simultaneously, it designs an Earth occlusion avoidance strategy during the lunar scan process to ensure lunar visibility. This prediction and verification process does not require ground-based calculations, greatly simplifying ground-based strategy formulation and verification work, improving work efficiency and satellite autonomy. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a flowchart of a payload autonomous lunar scanning method based on sunlight avoidance provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the angle between the satellite, moon, and sun at an intermediate scanning moment provided in an embodiment of the present invention; Figure 3 This is a quaternion determination diagram of the target attitude at an intermediate scanning moment provided by an embodiment of the present invention; Figure 4 This is a structural diagram of a payload autonomous lunar scanning device based on sunlight avoidance provided in an embodiment of the present invention; Figure 5 This is a hardware architecture diagram of a computer device provided in an embodiment of the present invention. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0014] As described above, the existing inertia scanning mode does not consider the sunlight avoidance requirement, and needs to determine the moon scanning strategy on the ground in advance before each on-orbit calibration, and confirm the sunlight avoidance effect, resulting in a high cost of determining the moon scanning strategy.

[0015] Based on this, the concept of the present application is to design a load autonomous moon scanning method according to the motion characteristics of the satellite, the sun and the moon, which can autonomously complete sunlight avoidance to ensure load safety.

[0016] The specific implementation of the above concept is described below.

[0017] Please refer to Figure 1 The load autonomous moon scanning method based on sunlight avoidance provided by the embodiment of the present application comprises: Step 100, according to the calibration requirement, installation condition and layout characteristics of the satellite load, the moon scanning axis of the satellite load, the scanning angular velocity, the scanning total time length and the sunlight avoidance angle range are determined; Step 102, according to the moon scanning axis and the position prediction information of the satellite load in the future period, the scanning center time of the satellite load and the target attitude of the scanning center time are determined; wherein the position prediction information comprises a satellite orbit position vector, a sun position vector and a moon position vector; Step 104, according to the target attitude, the scanning angular velocity and the scanning total time length, the sunlight avoidance review of the scanning process and the acceleration and deceleration process of the satellite load is carried out in turn, and the scanning start-stop information and the acceleration and deceleration start-stop information of the satellite load when the sunlight avoidance is correctly completed are determined; Step 106, according to the scanning start-stop information, the acceleration and deceleration start-stop information and the preset maneuver preparation time, the motion state of the satellite load is adjusted, so that the moon scanning of the satellite load is completed.

[0018] In the embodiment of the present application, according to the calibration requirement and installation condition of the load, the moon scanning axis, the scanning angular velocity and the scanning total time length are determined in advance, and the sunlight avoidance angle range is determined according to the load layout and load characteristics; then the scanning center time of the satellite load and the corresponding target attitude are determined according to the prediction information of the satellite load, and the sunlight avoidance review of the scanning process and the acceleration and deceleration process is carried out according to the scanning center time to determine the start-stop time and the corresponding attitude quaternion when the sunlight avoidance is correct; finally, the running state of the satellite load is adjusted according to these start-stop time and attitude quaternion, and the moon scanning is completed. According to the motion characteristics of the satellite, the sun and the moon, the autonomous sunlight avoidance strategy is designed to ensure the load safety during the moon scanning process, and the moon blocking avoidance strategy during the moon scanning process is designed to ensure the moon visibility during the moon scanning process. This prediction and review process does not need the ground to participate in the calculation, greatly simplifies the strategy formulation and review work of the ground, and improves the work efficiency and satellite autonomy.

[0019] The execution mode of each step is described below. Figure 1

[0020] Firstly, for step 100, according to the calibration requirement, installation condition and layout characteristics of the satellite payload, the moon scanning axis of the satellite payload, the scanning angular velocity, the total scanning time length and the sunlight avoidance angle range are determined.

[0021] In the embodiment of the application, for a conventional earth imaging satellite, the load optical axis direction is the satellite +Z axis, or in the satellite XOZ plane and the satellite +Z axis has an included angle of Theta (positive near +X axis and negative near -X axis), and thus the scanning rotation axis is +Y axis.

[0022] The inertial scanning angular velocity is determined by the load, and the range of [0.1° / s, 1.6° / s] can be arbitrarily set.

[0023] The total scanning time length is also determined by the load layout and the scanning angular velocity, for example, a certain satellite has two loads, the load optical axis direction is in the satellite XOZ plane and the satellite +Z axis has an included angle of Theta1 and Theta2, and then the total scanning time length is calculated by the following formula: In the formula, Ts is the total scanning time length, Ws is the scanning angular velocity, and T is the reserved stable time.

[0024] Further, the sunlight avoidance angle range is determined according to the load layout and the load characteristics; generally, the satellite +Z axis is taken as the center and the circular cone range with a half-cone angle of 90 degrees (which can be set) is taken as the sun avoidance range.

[0025] Then, for step 102, according to the moon scanning axis and the position prediction information of the satellite payload in a future period, the scanning center time of the satellite payload and the target attitude at the scanning center time are determined.

[0026] In the embodiment of the application, the scanning center time of the satellite payload and the target attitude at the scanning center time are determined by the following way: according to the predicted values of the satellite orbit position vector, the sun position vector and the moon position vector of the satellite payload in a future period, the first included angle between the satellite pointing sun vector and the satellite pointing moon vector and the second included angle between the satellite pointing earth center vector and the satellite pointing moon vector are calculated; the time when the first included angle is not less than 130° and the second included angle is not less than 45° in the future period is determined as the scanning center time with the best scanning effect; the moon scanning axis of the satellite payload is adjusted at the scanning center time according to the preset standard, and the target attitude of the satellite payload at the scanning center time is obtained by vector calculation according to the adjusted scanning axis.

[0027] ​Specifically, when the satellite works in a long-term normal operation mode, a satellite orbit position vector SAT = [SATx, SATy, SATz], a sun position vector SUN = [SUNx, SUNy, SUNz] and a moon position vector MOON = [MOONx, MOONy, MOONz] of a "current satellite time + future time" can be predicted, and the length of the predicted future time period can be adjusted according to actual needs.

[0028] Then, a first included angle THETA1 between the satellite pointing sun vector and the satellite pointing moon vector is calculated according to the predicted information. In the formula, the modulus of the vector is taken. Meanwhile, a second included angle THETA2 between the satellite pointing earth center vector and the satellite pointing moon vector is calculated. The first included angle and the second included angle are both in a range of [0°, 180°], and the satellite orbit position vector, the sun position vector and the moon position vector are all represented in a vector in an earth-centered equatorial inertial coordinate system.

[0029] Further, a first included angle not less than 130 degrees (which can be set) and a second included angle not less than 45 degrees (which can be set) are selected as a scanning middle moment T*. Figure 2 As shown in the formula, the first included angle not less than 130 degrees (which can be set) can ensure that the satellite +Z axis pointing direction has a large included angle with the sun vector during the scanning process, and the second included angle not less than 45 degrees (which can be set) can ensure that the earth does not block the moon vector during the scanning process.

[0030] Further, a target attitude Qm needs to adjust the moon scanning axis of the satellite payload, as shown in the formula. Figure 3 As shown in the formula, the satellite +Z axis is required to point to the moon, the satellite +Y axis is perpendicular to the satellite pointing moon vector and is located in a plane determined by the satellite, the moon and the sun, the satellite +X axis is perpendicular to the satellite pointing moon vector and is perpendicular to the satellite pointing sun vector, and the satellite +X, +Y and +Z axes form a right-handed orthogonal coordinate system.

[0031] The target attitude Qm is calculated by the following formula. In the formula, the cross product of the vector is calculated; and C is a direction cosine matrix corresponding to the target attitude Qm.

[0032] The C matrix is converted into a unit quaternion to obtain the target attitude Qm.

[0033] ​For step 104, according to the target attitude, the scanning angular velocity and the total scanning time, the satellite payload is sequentially subjected to a scanning process and a speed-up and speed-down process for sunlight avoidance review, to determine the scanning start-stop information and the speed-up and speed-down start-stop information when the satellite payload correctly completes the sunlight avoidance.

[0034] In the embodiment of the application, the start-stop information is determined by the following method: the scanning start-stop time and the corresponding scanning start-stop attitude of the scanning process are calculated according to the scanning center time, the target attitude, the scanning angular velocity and the total scanning time; it is judged whether the included angle between the +Z axis of the satellite payload and the satellite pointing sun vector at the scanning process start-stop time is greater than 90°, if yes, it is determined that the scanning process correctly completes the sunlight avoidance, otherwise, the scanning center time of the satellite payload is re-determined; the acceleration start time and the acceleration attitude of the speed-up and speed-down process, and the deceleration stop time and the deceleration attitude are calculated according to the scanning center time, the target attitude, the scanning angular velocity, the total scanning time, the scanning start-stop time and the scanning start-stop attitude; it is judged whether the included angle between the +Z axis of the satellite payload and the satellite pointing sun vector at the acceleration start time and the deceleration stop time of the speed-up and speed-down process is greater than 90°, if yes, it is determined that the speed-up and speed-down process correctly completes the sunlight avoidance, otherwise, the scanning center time of the satellite payload is re-determined.

[0035] Specifically, first, the scanning start time Ts and the scanning start attitude quaternion Qs are calculated according to the scanning center time and the target quaternion, the scanning angular velocity Ws and the total scanning time Ts, the scanning stop time Tend and the scanning stop attitude quaternion Qend are calculated, then the sunlight avoidance review of the scanning process is performed, the included angle between the +Z axis of the satellite and the satellite pointing sun vector at the scanning start time is calculated, the included angle between the +Z axis of the satellite and the satellite pointing sun vector at the scanning end time is calculated, if both of the two included angles are greater than 90 degrees (sun avoidance range), it is considered that the sunlight avoidance of the scanning process is correct.

[0036] Further, the acceleration start time and the acceleration attitude, and the deceleration stop time and the deceleration attitude are calculated according to the scanning center time and the target quaternion, the scanning angular velocity Ws and the total scanning time Ts, the scanning start time Ts and the scanning start attitude quaternion Qs, the scanning stop time Tend and the scanning stop attitude quaternion Qend, and then the included angle between the +Z axis of the satellite and the satellite pointing sun vector at the acceleration start time and the deceleration stop time is calculated, if both of the two included angles are greater than 90 degrees (sun avoidance range), it is considered that the sunlight avoidance of the speed-up and speed-down process is correct.

[0037] It is worth noting that the scanning motion process of the satellite is that the angular velocity is first accelerated from zero to the required scanning angular velocity, and then decelerated from the angular velocity to zero after the scanning is completed, so for the above review process, the acceleration stop time is the scanning start time; similarly, the scanning stop time is the deceleration start time, so there is no need to repeatedly calculate the attitude of the acceleration stop time and the deceleration start time.

[0038] For step 106, the motion state of the satellite payload is adjusted according to the scan start / stop information, the acceleration / deceleration start / stop information, and the preset maneuver preparation time, so that the satellite payload can complete the lunar scan.

[0039] In this embodiment of the invention, the maneuver preparation time is determined based on the difference between the acceleration start time and the sum of the time taken for the satellite payload to maneuver 360 degrees, the reserved rate damping time, and the reserved stabilization time. That is, the maneuver preparation time tm = acceleration start time - time taken for the satellite to maneuver 360 degrees - reserved rate damping time - reserved stabilization time.

[0040] Furthermore, after determining the start and stop times of the scanning and acceleration / deceleration processes through a verification process, the operating state of the satellite payload can be adjusted to complete the lunar scan. The adjustment process includes: when the satellite payload reaches the preset maneuver preparation time, reducing the inertial angular velocity of the satellite payload to 0, and setting the maneuver attitude to the acceleration attitude before reaching the acceleration start time; when the satellite payload reaches the acceleration start time, accelerating the inertial angular velocity of the satellite payload according to the acceleration attitude, so that the inertial angular velocity of the satellite payload accelerates to the scanning angular velocity at the scan start time, and changing the acceleration attitude to the scan start attitude; when the satellite payload reaches the scan start time, performing a uniform scan of the moon at the scanning angular velocity for a duration equal to the total scan duration, so that multiple payloads image the moon sequentially; when the satellite payload reaches the scan stop time, decelerating the inertial angular velocity of the satellite payload so that the inertial angular velocity drops to 0 at the deceleration stop time to complete the lunar scan, and restoring the maneuver attitude to the preset normal operating attitude after deceleration stops.

[0041] In summary, this method presents a fully autonomous lunar scanning strategy, significantly enhancing satellite autonomy. Furthermore, based on the motion characteristics of the satellite, the sun, and the moon, this method designs an autonomous sunlight avoidance strategy to ensure payload safety during the lunar scanning process. It also eliminates the need for ground-based calculations, greatly simplifying ground-based strategy formulation and verification, and improving work efficiency. In addition, this method is universal and can be extended to other satellite models that require lunar scanning.

[0042] Please refer to Figure 4 This invention provides an autonomous lunar scanning device based on sunlight avoidance, the device comprising: The first determining module 400 is used to determine the lunar scanning axis, scanning angular velocity, total scanning time, and sunlight avoidance angle range of the satellite payload based on the calibration requirements, installation conditions, and layout characteristics of the satellite payload. The second determination module 402 is configured to determine a scanning center moment of the satellite payload and a target attitude of the scanning center moment according to position prediction information of the satellite payload on the moon scanning axis and a future period, wherein the position prediction information comprises a satellite orbit position vector, a sun position vector and a moon position vector. The review module 404 is configured to perform sunlight avoidance review of a satellite payload on a scanning process and a speed-up / slow-down process in sequence according to the target attitude, the scanning angular velocity and the total scanning time length, and determine scanning start-stop information and speed-up / slow-down start-stop information when the satellite payload correctly completes sunlight avoidance. The scanning module 406 is configured to adjust a motion state of the satellite payload according to the scanning start-stop information, the speed-up / slow-down start-stop information and a preset maneuver preparation moment, so that the satellite payload completes the moon scanning.

[0043] In the embodiment of the application, when the second determination module 402 performs the operation of determining the scanning center moment of the satellite payload and the target attitude of the scanning center moment according to the position prediction information of the satellite payload on the moon scanning axis and the future period, the second determination module 402 is specifically configured to: calculate a first included angle between a satellite pointing sun vector and a satellite pointing moon vector and a second included angle between a satellite pointing earth center vector and the satellite pointing moon vector according to predicted values of the satellite orbit position vector, the sun position vector and the moon position vector of the satellite payload in the future period; determine a moment in the future period when the first included angle is not less than 130° and the second included angle is not less than 45° as the scanning center moment with the best scanning effect; and adjust the moon scanning axis of the satellite payload at the scanning center moment according to a preset standard, and perform vector calculation according to the adjusted moon scanning axis to obtain the target attitude of the satellite payload at the scanning center moment.

[0044] In the embodiment of the application, when the second determination module 402 performs the operation of adjusting the moon scanning axis of the satellite payload at the scanning center moment according to the preset standard, the second determination module 402 is specifically configured to: determine that a +Z axis of the satellite payload points to the moon, a +Y axis of the satellite payload is perpendicular to the satellite pointing moon vector and is located in a plane determined by the satellite, the moon and the sun, and a +X axis of the satellite payload is perpendicular to the satellite pointing moon vector and is perpendicular to a satellite pointing sun vector.

[0045] In the embodiment of the present application, when the review module 404 performs the sunlight avoidance review of the satellite load according to the target attitude, the scanning angular velocity and the total scanning time, and determines the scanning start-stop information and the acceleration-deceleration start-stop information when the satellite load correctly completes the sunlight avoidance, the review module 404 is specifically configured to perform the following operations: calculating the scanning start-stop time and the corresponding scanning start-stop attitude of the scanning process according to the scanning center time, the target attitude, the scanning angular velocity and the total scanning time; judging whether the angles between the +Z axis of the satellite load and the satellite sun-pointing vector at the scanning process start-stop time are greater than 90 degrees, and if yes, determining that the scanning process correctly completes the sunlight avoidance, otherwise, re-determining the scanning center time of the satellite load; calculating the acceleration start time and the acceleration attitude of the acceleration-deceleration process, and the deceleration stop time and the deceleration attitude according to the scanning center time, the target attitude, the scanning angular velocity, the total scanning time, the scanning start-stop time and the scanning start-stop attitude; judging whether the angles between the +Z axis of the satellite load and the satellite sun-pointing vector at the acceleration start time and the deceleration stop time of the acceleration-deceleration process are greater than 90 degrees, and if yes, determining that the acceleration-deceleration process correctly completes the sunlight avoidance, otherwise, re-determining the scanning center time of the satellite load.

[0046] In the embodiment of the present application, when the scanning module 406 performs the adjustment of the motion state of the satellite load according to the scanning start-stop information, the acceleration-deceleration start-stop information and the preset maneuver preparation time, so that the satellite load completes the moon scanning, the scanning module 406 is specifically configured to perform the following operations: when the satellite load runs to the preset maneuver preparation time, reducing the inertial angular velocity of the satellite load to 0, and setting the maneuver attitude to the acceleration attitude before reaching the acceleration start time; when the satellite load runs to the acceleration start time, accelerating the inertial angular velocity of the satellite load according to the acceleration attitude, so that the inertial angular velocity of the satellite load accelerates to the scanning angular velocity at the scanning start time, and the acceleration attitude changes to the scanning start attitude; when the satellite load runs to the scanning start time, continuously scanning the moon at the scanning angular velocity for the total scanning time, so that the multiple loads are imaged on the moon in turn; when the satellite load runs to the scanning stop time, decelerating the inertial angular velocity of the satellite load to 0 at the deceleration stop time to complete the moon scanning, and restoring the maneuver attitude to the preset normal running attitude after the deceleration stop.

[0047] In the embodiment of the present application, the maneuver preparation time is determined according to the difference between the acceleration start time and the sum of the satellite load maneuvering time for 360 degrees, the reserved rate damping time and the reserved stable time.

[0048] It should be noted that the load autonomous moon scanning device based on sunlight avoidance provided in the above embodiment is only exemplified by the division of the above functional modules. In actual application, the above functions can be completed by different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. In addition, the load autonomous moon scanning device based on sunlight avoidance provided in the above embodiment and the load autonomous moon scanning method based on sunlight avoidance embodiment belong to the same concept, and the specific implementation process is detailed in the method embodiment, which will not be repeated here.

[0049] Embodiments of the present application also provide a computer device, which refers to Figure 5 The computer device includes a processor and a memory, and the memory stores at least one instruction, at least one program, a code set or an instruction set. The at least one instruction, at least one program, code set or instruction set is loaded and executed by the processor to implement the load autonomous moon scanning method based on sunlight avoidance provided by each method embodiment.

[0050] Embodiments of the present application also provide a computer readable storage medium, which stores at least one instruction, at least one program, a code set or an instruction set. The at least one instruction, at least one program, code set or instruction set is loaded and executed by the processor to implement the load autonomous moon scanning method based on sunlight avoidance provided by each method embodiment.

[0051] Embodiments of the present application also provide a computer program product, which includes a computer program. The processor of the computer device reads the computer program from the computer readable storage medium. The processor executes the computer program, so that the computer device executes the load autonomous moon scanning method based on sunlight avoidance described in any of the above embodiments.

[0052] For the convenience of description, the above system or device is described as various modules or units respectively described in function. Of course, in the implementation of the present application, the functions of each unit can be implemented in the same or multiple software and / or hardware.

[0053] From the above description of the implementation mode, those skilled in the art can clearly understand that the present application can be realized by means of software and necessary general hardware platform. Based on such understanding, the technical solutions of the present application can be embodied in the form of software product, which can be stored in storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., including a plurality of instructions to make a computer device (which can be a personal computer, server, or network device, etc.) execute the method described in each embodiment or some parts of the embodiment of the present application.

[0054] Finally, it is to be understood that the phraseology or terminology such as "first," "second," "third," "fourth," and the like in the specification is for the purpose of differentiating one element from another element only and is not necessarily intended to imply any actual relationship or order between such elements. Also, the use of "including," "comprising," or "having" and variations thereof in the specification are intended to encompass the presence of one or more elements or steps but not preclude the presence of additional elements or steps. The use of "including," "comprising," or "having" and variations thereof in the specification does not preclude the presence of additional elements or steps.

[0055] The above description is merely that of the preferred embodiments of the application and modifications and alterations are possible as apparent to those having ordinary skill in the art without departing from the principles of the application.

Claims

1. A method for autonomous lunar scanning by a payload based on sunlight avoidance, characterized in that, The method includes: Based on the calibration requirements, installation status, and layout characteristics of the satellite payload, determine the lunar scanning axis, scanning angular velocity, total scanning time, and sunlight avoidance angle range of the satellite payload. Based on the lunar scanning axis and the satellite payload's position prediction information for future time periods, the scanning center time of the satellite payload and the target attitude at the scanning center time are determined; wherein, the position prediction information includes the satellite orbital position vector, the sun position vector, and the moon position vector; Based on the target attitude, the scanning angular velocity, and the total scanning time, the satellite payload is sequentially checked for sunlight avoidance during the scanning process and the acceleration / deceleration process to determine the scanning start / stop information and acceleration / deceleration start / stop information when the satellite payload correctly completes sunlight avoidance. The motion state of the satellite payload is adjusted according to the scan start / stop information, the acceleration / deceleration start / stop information, and the preset maneuver preparation time, so that the satellite payload can complete the lunar scan.

2. The method as described in claim 1, characterized in that, The step of determining the scanning center time of the satellite payload and the target attitude at the scanning center time based on the lunar scanning axis and the satellite payload's position prediction information for future time periods includes: Based on the satellite payload's predicted values ​​of the satellite's orbital position vector, solar position vector, and lunar position vector for future periods, the first angle between the satellite's solar pointing vector and the satellite's lunar pointing vector, as well as the second angle between the satellite's geocentric vector and the satellite's lunar pointing vector, are calculated. The time when the first included angle is not less than 130° and the second included angle is not less than 45° within a future time period is determined as the scanning center time with the best scanning effect. According to the preset standard, the lunar scanning axis of the satellite payload is adjusted at the scanning center time, and vector calculation is performed based on the adjusted scanning axis to obtain the target attitude of the satellite payload at the scanning center time.

3. The method as described in claim 2, characterized in that, The step of adjusting the lunar scanning axis of the satellite payload at the scanning center time according to a preset standard includes: The satellite payload's +Z axis is determined to point towards the moon, the satellite payload's +Y axis is perpendicular to the satellite's vector pointing towards the moon and the satellite's +Y axis lies within the plane defined by the three points "satellite-moon-sun", and the satellite payload's +X axis is perpendicular to both the satellite's vector pointing towards the moon and the satellite's vector pointing towards the sun.

4. The method as described in claim 1, characterized in that, The process of verifying the sun avoidance of the satellite payload during the scanning and acceleration / deceleration processes based on the target attitude, the scanning angular velocity, and the total scanning time, and determining the scanning start / stop information and acceleration / deceleration start / stop information when the satellite payload correctly completes sun avoidance, includes: The scanning start and stop times and corresponding scanning start and stop attitudes are calculated based on the scanning center time, target attitude, scanning angular velocity and total scanning time. Determine whether the angle between the satellite payload + Z-axis and the satellite's sun-pointing vector is greater than 90° at the start and stop times of the scanning process. If so, the scanning process is confirmed to have successfully completed the sun avoidance; otherwise, the scanning center time of the satellite payload is re-determined. The acceleration start time and acceleration attitude, as well as the deceleration stop time and deceleration attitude, are calculated based on the scanning center time, target attitude, scanning angular velocity, total scanning duration, scanning start and stop time, and scanning start and stop attitude. Determine whether the angle between the satellite payload +Z axis and the satellite's sun-pointing vector is greater than 90 degrees at both the acceleration start and deceleration stop times during the acceleration and deceleration process. If so, confirm that the acceleration and deceleration process has correctly completed sunlight avoidance; otherwise, re-determine the scanning center time of the satellite payload.

5. The method as described in claim 4, characterized in that, The step of adjusting the motion state of the satellite payload according to the scan start / stop information, the acceleration / deceleration start / stop information, and the preset maneuver preparation time to enable the satellite payload to complete the lunar scan includes: When the satellite payload reaches the preset maneuver preparation time, the inertial angular velocity of the satellite payload is reduced to 0, and the maneuver attitude is set to the acceleration attitude before the acceleration start time is reached. When the satellite payload reaches the acceleration start time, the inertial angular velocity of the satellite payload is accelerated according to the acceleration attitude, so that the inertial angular velocity of the satellite payload is accelerated to the scanning angular velocity at the scanning start time, and the acceleration attitude is changed to the scanning start attitude. When the satellite payload reaches the scan start time, it performs a uniform scan of the moon at the scan angular velocity for a duration equal to the total scan duration, so that multiple payloads image the moon sequentially. When the satellite payload reaches the scanning stop time, the inertial angular velocity of the satellite payload is decelerated so that the inertial angular velocity drops to 0 at the deceleration stop time to complete the lunar scan, and the maneuver attitude is restored to the preset normal operating attitude after the deceleration stops.

6. The method as described in claim 4, characterized in that, The maneuver preparation time is determined based on the difference between the acceleration start time and the sum of the time taken for the satellite payload to maneuver 360 degrees, the reserved rate damping time, and the reserved stabilization time.

7. A payload-based autonomous lunar scanning device based on sunlight avoidance, characterized in that, The device includes: The first determining module is used to determine the lunar scanning axis, scanning angular velocity, total scanning time, and sunlight avoidance angle range of the satellite payload based on the calibration requirements, installation conditions, and layout characteristics of the satellite payload. The second determining module is used to determine the scanning center time of the satellite payload and the target attitude at the scanning center time based on the lunar scanning axis and the position prediction information of the satellite payload for future time periods; wherein, the position prediction information includes the satellite orbit position vector, the sun position vector and the moon position vector; The verification module is used to verify the sunlight avoidance of the satellite payload during the scanning process and acceleration / deceleration process according to the target attitude, the scanning angular velocity and the total scanning time, and to determine the scanning start and stop information and acceleration / deceleration start and stop information when the satellite payload correctly completes sunlight avoidance. The scanning module is used to adjust the motion state of the satellite payload according to the scanning start / stop information, the acceleration / deceleration start / stop information, and the preset maneuver preparation time, so that the satellite payload can complete the lunar scan.

8. A computer device, characterized in that, The computer device includes a memory and a processor. The memory is used to store computer programs, and the processor is used to execute the computer programs stored in the memory to implement the steps of the method according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The storage medium stores a computer program, which, when executed by a processor, implements the steps of the method described in any one of claims 1-6.

10. A computer program product, characterized in that, Includes a computer program, which, when executed by a processor, implements the steps of the method according to any one of claims 1-6.

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