Star autonomous task planning method based on ground attribute prediction result of a star point

Abstract

This invention discloses a fully autonomous onboard mission planning method based on the prediction results of surface attributes at nadir points. This invention makes full use of the digital maps stored in the satellite navigation and positioning system. According to the satellite's mission content, it pre-sets fully autonomous domestic observation missions, fully autonomous sunny land observation missions, and fully autonomous solar calibration missions. By obtaining surface attributes such as land / ocean, sunshine / shade, and domestic / overseas, the start and end times of the missions are obtained, realizing the autonomous generation of missions. This solves the dependence of satellite observation missions on ground operation and control systems, realizes the autonomous controllability of observation missions, and improves the utilization rate and ease of use of satellite payloads.

Description

Technical Field

[0001] This invention relates to the field of on-board mission planning technology, and specifically to an on-board fully autonomous mission planning method based on the prediction results of surface attributes at sub-satellite points. Background Technology

[0002] Traditional satellite-based Earth observation methods rely on ground-based mission planning, requiring human intervention to predict satellite flight trajectories and analyze the relative relationship between the observed object and ground-based points. The satellite passively receives and executes observation tasks reported from the ground. Due to limitations such as short satellite-to-ground interaction times, satellites cannot respond quickly to dynamic changes in observation needs.

[0003] Thanks to the development of spaceborne electronic technology, satellite autonomous mission planning technology has become a research hotspot in the aerospace field. The paper "Research on On-Orbit Real-Time Guided Multi-Satellite Imaging Mission Planning Method" (Spacecraft Engineering, 2019, No. 5) proposes a multi-satellite autonomous mission planning method for on-orbit real-time guided imaging. This method transforms the satellite payload's visibility to the target into "time-attitude" information, designs a conflict-free mission sequence generation method and an ad-hoc adjustment strategy, and can be used for satellite autonomous planning of multi-point target observation missions, but is not suitable for the autonomous generation and management of regional target missions.

[0004] Current research on on-board autonomous mission planning technology focuses primarily on point targets, and no patents yet involve planning methods for regional targets. Summary of the Invention

[0005] In view of this, the present invention provides a fully autonomous on-board mission planning method based on the surface attribute prediction results of the satellite sub-satellite point, which solves the dependence of satellite-oriented regional target observation missions on the ground operation and control system, realizes the autonomous controllability of observation missions, and improves the utilization rate and ease of use of satellite payloads.

[0006] A fully autonomous onboard mission planning method based on nadir point surface attribute prediction results firstly pre-sets mission templates for the satellite software. Then, based on the nadir point surface attributes predicted by the satellite, it autonomously identifies imaging regions that meet the boundary conditions of each mission, and obtains the times of entering and exiting the imaging regions as the start and end times of the mission. Combined with the pre-set mission templates, autonomous missions are generated. The satellite continuously generates autonomous missions according to the above method. Before each mission execution, conflict detection is performed between the generated main missions and between the main missions and ground-based missions. Missions without conflicts are merged and executed; missions with conflicts are deleted.

[0007] Preferably, the mission templates include fully autonomous domestic observation missions, fully autonomous solar eclipse land observation missions, and fully autonomous solar calibration missions.

[0008] Preferably, based on the satellite-predicted nadir point attributes, the imaging area of ​​the fully autonomous domestic observation mission is identified, and the domestic observation time at the mission start and end times is obtained using the following method:

[0009] The satellite navigation and positioning system periodically acquires information about the domestic / overseas location of the navigator 90 minutes after the forecast. If the information is "domestic" for 6 consecutive times, the time T10 of the first acquisition of "domestic" information will be taken as the start time of the mission.

[0010] Afterwards, the satellite navigation and positioning system continues to periodically acquire the domestic / overseas information of the sub-satellite point 90 minutes later. Once "overseas information" is acquired 6 times in a row, the satellite time T11 of the first acquisition of "overseas information" is taken as the end time of the mission. If "overseas information" is not acquired 6 times in a row within a period of time starting from T10, the acquired T10 time is abandoned, and the domestic observation method is used to re-evaluate.

[0011] Preferably, based on the satellite-predicted nadir point attributes, the imaging area of ​​the fully autonomous solar-lit land observation mission is identified, and the method for obtaining the solar-lit land observation data at the mission start and end times is as follows:

[0012] The system periodically acquires the nadir sunlight / shadow information predicted by the satellite navigation and positioning system 90 minutes later. Once it acquires "sunlight information" 10 times consecutively, it begins to determine land / ocean information. Once it acquires "land information" 6 times consecutively, the time T20 of the first acquisition of "overseas information" is taken as the start time of the mission.

[0013] Then, continue to periodically acquire the nadir illumination / shadow information predicted by the satellite navigation and positioning system 90 minutes later. If "shadow information" is acquired 10 times consecutively or "ocean information" is acquired 6 times consecutively, then the time T21 corresponding to the first acquisition of "shadow information" or the first acquisition of "ocean information" is taken as the end time of the mission. If there are no 10 consecutive acquisitions of "shadow information" or no 6 consecutive acquisitions of "ocean information" within a period of time starting from T20, then the acquired time T20 is discarded, and the assessment is re-evaluated according to the sunshine land observation method described above.

[0014] Preferably, based on the satellite-predicted nadir point attributes, the imaging area of ​​the fully autonomous solar calibration mission is identified, and the solar calibration method for obtaining the mission start and end times is as follows:

[0015] The system periodically acquires the nadir illumination / shadow information predicted by the satellite navigation and positioning system 90 minutes later. Once a shadow turns into sunshine, it starts recording the number of times sunshine information is acquired. When the number of sunshine information acquisitions reaches 10, the orbit count is incremented by 1; otherwise, it continues to judge whether shadow turns into sunshine. When the orbit count is 15, the satellite time T3 of the first acquisition of "sunshine information" on the 15th orbit is recorded. T30 = T3 - 3 min is taken as the start time of the mission, and T31 = T3 - 1 min is taken as the end time of the mission.

[0016] Preferably, the task duration is calculated based on the start and end times of each task. If the task duration is ≥60 seconds, the task is considered executable and conflict detection is performed; if the task duration is less than 60 seconds, the task is deleted.

[0017] Ideally, when a conflict is detected, only the latest task is retained, and the remaining conflicting tasks are deleted.

[0018] Preferably, when the satellite software presets various mission templates, multiple mission templates are preset according to the type of mission the satellite is to perform, and users can select one or more templates according to their observation needs.

[0019] Beneficial effects

[0020] 1. This invention fully utilizes the digital maps stored in satellite navigation and positioning systems to autonomously plan observation tasks based on predicted surface attributes such as land / sea, sunshine / shade, and domestic / overseas locations. Compared to task planning methods targeting point targets, this invention enables autonomous task generation based on characteristic regional targets.

[0021] 2. Based on the satellite's operational content, fully autonomous domestic observation missions, fully autonomous sunny land observation missions, and fully autonomous solar calibration missions are pre-set. By obtaining surface attributes such as land / ocean, sunshine / shade, and domestic / overseas, the start and end times of the missions are obtained, realizing the autonomous generation of missions. This solves the dependence of satellite observation missions on ground operation and control systems, achieves autonomous control of observation missions, and improves the utilization rate and ease of use of satellite payloads.

[0022] 3. Real-time statistics and analysis are performed based on the satellite's predicted surface attributes of nadir points 90 minutes later—whether they are domestic or foreign. When conducting fully autonomous domestic observation missions, the characteristics of the domestic area are analyzed: continuous acquisition of "domestic information" indicates entry into the domestic territory; continuous acquisition of "foreign information" indicates exit from the domestic territory. Based on this pattern, it is possible to accurately analyze whether the surface attributes of the target area at the current nadir point are within the domestic territory. Furthermore, by recording the times of the first entry and exit as the start and end times of the mission, it is possible to autonomously identify imaging areas that meet the boundary conditions and generate independent observation missions. This method, by analyzing the characteristics of the domestic area and setting corresponding judgment conditions, enables the execution of fully autonomous domestic observation missions, eliminating the dependence of domestic area observation missions on ground-based operation and control systems.

[0023] 4. Based on the satellite's predicted surface attributes 90 minutes later—sunlight / shade and land / ocean information—real-time statistics and analysis are performed. When conducting a fully autonomous sunny land observation mission, the characteristics of sunny land are analyzed: first, the sunlight attribute is determined; if "sunlight information" is continuously obtained, it is considered to be in sunny conditions; subsequently, if "land information" is continuously obtained, it is considered to be in sunny land conditions; if "shade information" or "ocean information" is continuously obtained, it is considered to have left the sunny land area. Based on this pattern, imaging areas meeting the boundary conditions can be autonomously identified, generating independent observation tasks. This method, by analyzing the characteristics of sunny land areas and setting corresponding judgment conditions, enables the execution of fully autonomous sunny land observation missions, eliminating the dependence of fully autonomous sunny land area observation missions on ground control systems.

[0024] 5. Based on the satellite's predicted surface attributes—sunshine / shade information—90 minutes later, real-time statistics and analysis are performed. During fully autonomous solar calibration, the system analyzes solar characteristics: when sunshine information is obtained several times consecutively, it is considered to have entered sunshine. Based on past experience, a certain range of sunshine entry times is used as the start and end times of the solar calibration task. According to this pattern, the system can autonomously identify imaging areas that meet the boundary conditions and generate independent observation tasks. This method, by analyzing the patterns of solar calibration tasks and combining past experience, sets corresponding judgment conditions, enabling the execution of fully autonomous solar calibration tasks and eliminating the dependence of fully autonomous solar calibration tasks on ground control systems.

[0025] 6. To ensure task integrity and avoid false alarms or erroneous tasks, task duration is checked. The task will only be executed if its duration exceeds the threshold time; otherwise, the task will be deleted.

[0026] 7. This invention performs legality checks on the duration of autonomously generated observation tasks, detects task conflicts, and merges overlapping tasks that pass the checks to generate executable tasks. This method can simultaneously manage both satellite-generated autonomous tasks and ground-based specific tasks. By autonomously eliminating tasks that do not meet the execution conditions, this method enables the satellite to achieve autonomous task management independently of the ground control system, simplifying the satellite-ground interface.

[0027] 8. This invention can modify the surface attributes of the selected nadir point by ground annotation, and realize observation tasks under different surface characteristics according to user needs, making the observation object flexible and controllable. Attached Figure Description

[0028] Figure 1 This is a flowchart of the method proposed in this invention for autonomously generating domestic observation tasks based on domestic / overseas surface attributes;

[0029] Figure 2 This is a flowchart of the method proposed in this invention for autonomously generating solar land observation tasks based on sunlight / shade and land / ocean surface attributes;

[0030] Figure 3 This is a flowchart of the method for autonomously generating solar calibration tasks based on the surface attributes of sunlight / shade proposed in this invention;

[0031] Figure 4 This is a block diagram of the autonomous task management method proposed in this invention. Detailed Implementation

[0032] The implementation of the method of the present invention will be described below with reference to the accompanying drawings and embodiments.

[0033] This invention provides a fully autonomous onboard mission planning method based on nadir point surface attribute prediction results. The basic idea is as follows: First, pre-set corresponding judgment conditions in the satellite software. Then, during satellite operation, based on information predicted by the satellite navigation and positioning system, including land / ocean, sunshine / shade, and domestic / overseas information, perform real-time statistical analysis to autonomously identify imaging areas that meet boundary condition requirements, determine the current nadir point surface attributes, and execute corresponding tasks according to the mission requirements of different surface attributes, thus achieving autonomous onboard mission planning. Furthermore, to prevent mission conflicts, conflict judgments are made between primary missions and between autonomous missions and tasks assigned on the ground to achieve mission management. The specific method is as follows:

[0034] S1. Preset mission templates for satellite software, including templates for fully autonomous domestic observation missions, fully autonomous solar eclipse land observation missions, and fully autonomous solar calibration missions.

[0035] S2. During satellite operation, the satellite acquires relevant information in real time, obtaining the start and end times corresponding to the three mission conditions in step S1. The specific determination method is as follows:

[0036] S2.1 Assessment of Fully Autonomous Domestic Observation Missions:

[0037] like Figure 1 As shown, the satellite navigation and positioning system acquires the domestic / overseas information of the nadir point predicted 90 minutes later every 5 seconds. Once six consecutive acquisitions show "domestic information," the surface attribute of the current nadir point is considered to be domestic. At this point, the satellite time T of the first acquisition of "domestic information" is recorded. 10 The moment determined as the first entry point under the star is about to be T. 10 As the starting point of the mission;

[0038] Then, every 5 seconds, the satellite navigation and positioning system will predict whether the nadir point is within or outside the country 90 minutes later. If six consecutive "outside information" results are obtained, the surface attribute of the current nadir point is considered to be outside the country. At this point, the satellite time T of the first "outside information" acquisition will be recorded. 11 The moment determined to be the first departure of the star-shaped point is about to be T. 11 As the end time of the mission; since the satellite continuously acquires information, in practice, it will obtain the start and end times of multiple fully autonomous domestic observation missions.

[0039] If from time T 10 If no "overseas information" is obtained for 6 consecutive times within 50 minutes, the obtained T will be forfeited. 10 At that moment, reassess using the method described above.

[0040] S2.2 Fully Autonomous Sunlight Land Observation Mission Assessment:

[0041] like Figure 2 As shown, the system acquires the 90-minute forecast of sunlight / shadow information for the nadir point every 5 seconds. If 10 consecutive acquisitions show "sunlight information," the current nadir point's surface attribute is considered to be sunlight. Then, it determines land / ocean information; if 6 consecutive acquisitions show "land information," the current nadir point's surface attribute is considered to be sunny / land. At this point, the time T for the first acquisition of "overseas information" is... 20 This is determined to be the first land-based moment, which is about to begin (T). 20 As the starting point of the mission;

[0042] Then, the system continues to acquire the nadir illumination / shadow information predicted by the satellite navigation and positioning system 90 minutes later every 5 seconds. If 10 consecutive acquisitions show "shadow information" or 6 consecutive acquisitions show "ocean information," the current nadir point is considered to have a shadow attribute or be in the ocean. At this point, the time T corresponding to the first acquisition of "shadow information" or the first acquisition of "ocean information" is recorded. 21 As the end point of the mission; (T) 20 T 21 This is a time set for a fully autonomous solar-powered land observation mission. Because the satellite continuously acquires information, in practice, multiple start and end times for fully autonomous solar-powered land observation missions will be obtained.

[0043] If from time T 20 If no "Shadow Information" is obtained for 10 consecutive times or no "Ocean Information" is obtained for 6 consecutive times within 50 minutes, the obtained T is discarded. 20 At that moment, reassess using the method described above.

[0044] S2.3 Fully Autonomous Calibration Mission Judgment:

[0045] like Figure 3 As shown, the system acquires the nadir illumination / shadow information predicted by the satellite navigation and positioning system 90 minutes later every 5 seconds. If a shadow-to-sunlight transition occurs (i.e., the previous acquisition was shadow information, and the current acquisition is sunlight information), the system begins recording the number of times sunlight information is acquired. When the number of sunlight acquisitions reaches 10, the orbit count is incremented by 1; otherwise, the system continues to check for shadow-to-sunlight transitions. When the orbit count reaches 15, the satellite time T3, the first acquisition of "sunlight information" on the 15th orbit, is recorded. 30 =T3-3min is taken as the start time of the task, and T is set as... 31 =T3-1min is taken as the end time of the task. (T 30 T 31 This serves as a time group for a solar calibration mission. Because the satellite continuously acquires information, in practice, multiple start and end times for fully autonomous solar calibration missions will be obtained.

[0046] S3, such as Figure 4 As shown, for each task obtained in step S2, the task duration is determined based on its start and end times. If the task duration is ≥60s, the task is considered executable and proceeds to step S4; otherwise, the task is deleted.

[0047] S4. Based on the start and end times of each task obtained in step S2, select the corresponding task template, generate autonomous tasks, and perform conflict detection on the lateral movement sequences of all executable fully autonomous tasks and ground-based tasks. If there is enough time for lateral movement and no conflict, proceed to step S5; otherwise, process the conflicting tasks, retain only the latest task, and delete the rest.

[0048] S5. Merge and judge the data transmission record sequences in the fully autonomous mission and the ground-based mission. If the power-off command of the previous mission overlaps with the power-on command of the next mission, merge the missions and cancel the transmission of these two sets of commands. Otherwise, call the relevant mission commands to send.

[0049] By continuously obtaining multiple combinations of start and end times corresponding to the three major tasks according to the methods of S1 to S2, and managing autonomous tasks according to the methods of S3 to S5, the management and implementation of fully autonomous tasks can be completed.

[0050] Furthermore, before launch, the satellite can autonomously set the observation modes to be executed based on the landmark attributes of the nadir points it needs to observe, including fully autonomous domestic observation missions, fully autonomous solar-lit land observation missions, and fully autonomous solar calibration missions. For example, if the satellite needs to observe the domestic situation, it only needs to be configured for fully autonomous domestic observation missions.

[0051] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A fully autonomous onboard mission planning method based on sub-satellite point surface attribute prediction results, characterized in that: First, preset templates for each mission in the satellite software; Then, based on the surface properties of the sub-satellite points predicted by the satellite, the autonomous system identifies imaging areas that meet the boundary conditions of each mission, obtains the times of entering and exiting the imaging areas as the start and end times of the mission, and generates autonomous missions by combining them with preset mission templates. The satellite continuously generates autonomous missions using the above method. Before each mission is executed, conflict detection is performed between the generated main missions and between the main missions and the missions registered on the ground. Missions without conflicts are merged and executed; missions with conflicts are deleted. The task templates include fully autonomous domestic observation tasks, fully autonomous solar eclipse land observation tasks, and fully autonomous solar calibration tasks. Based on the satellite-predicted nadir point attributes, the imaging area of ​​the fully autonomous solar calibration mission is identified, and the solar calibration method for obtaining the mission start and end times is as follows: The system periodically acquires the nadir illumination / shadow information predicted by the satellite navigation and positioning system 90 minutes later. Once a shadow transitions to sunlight, it begins recording the number of times sunlight information is acquired. When the number of sunlight acquisitions reaches 10, the orbit count is incremented by 1; otherwise, it continues to check for shadow-to-sunlight transitions. When the orbit count reaches 15, the satellite time T3, the time of the first acquisition of "sunlight information" on the 15th orbit, is recorded. 30 =T3-3min is taken as the start time of the task, and T is set as... 31 =T3-1min is taken as the end time of the task; The data transmission record sequences in fully autonomous missions and ground-based missions are merged and judged. If the power-off command of the previous mission overlaps with the power-on command of the next mission, the missions are merged and the transmission of these two sets of commands is canceled. Otherwise, the relevant mission commands are called and sent.

2. The on-board fully autonomous mission planning method as described in claim 1, characterized in that: Based on the satellite-predicted nadir point attributes, the imaging area of ​​the fully autonomous domestic observation mission is identified, and the domestic observation method for obtaining the mission start and end times is as follows: The system periodically acquires 90-minute forecasts from the satellite navigation and positioning system regarding whether the nadir is domestic or international. If six consecutive acquisitions show "domestic information," the time T of the first acquisition of "domestic information" will be changed. 10 As the starting point of the mission; Then, it continues to periodically acquire the satellite navigation and positioning system's forecast of the nadir point's domestic / overseas status 90 minutes later. If it acquires "overseas information" six times consecutively, then the satellite time T of the first acquisition of "overseas information" will be changed. 11 As the end point of the task; if from T 10 If no "overseas information" is received for six consecutive periods within a specified time period, the obtained T will be forfeited. 10 At that time, and re-evaluate according to the aforementioned domestic observation methods.

3. The on-board fully autonomous mission planning method as described in claim 1, characterized in that: Based on the satellite-predicted nadir point attributes, the imaging area of ​​the fully autonomous solar-lit land observation mission is identified, and the method for obtaining the solar-lit land observation data at the mission start and end times is as follows: The system periodically acquires 90-minute forecasts of nadir sunlight / shadow information from the satellite navigation and positioning system. Once 10 consecutive "sunlight information" acquisitions are received, it begins determining land / ocean information. Once 6 consecutive "land information" acquisitions are received, the time T for the first acquisition of "overseas information" is changed. 20 As the starting point of the mission; Then, continue to periodically acquire the nadir illumination / shadow information predicted by the satellite navigation and positioning system 90 minutes later. If "shadow information" is acquired 10 times consecutively or "ocean information" is acquired 6 times consecutively, then the time T corresponding to the first acquisition of "shadow information" or the first acquisition of "ocean information" will be recorded. 21 As the end point of the task; if from T 20 If no "Shadow Information" is obtained 10 times consecutively or no "Ocean Information" is obtained 6 times consecutively within the initial period, the obtained T is discarded. 20 At that time, the judgment should be re-evaluated according to the aforementioned method for observing land under sunlight.

4. The on-board fully autonomous mission planning method as described in claim 1, 2, or 3, characterized in that: Calculate the task duration for each task based on its start and end times. If the task duration is ≥60 seconds, the task is considered executable and conflict detection is performed; if the task duration is less than 60 seconds, the task is deleted.

5. The on-board fully autonomous mission planning method as described in claim 1, 2, or 3, characterized in that: When a conflict is detected, only the latest task is kept, and the remaining tasks with conflicts are deleted.

6. The on-board fully autonomous mission planning method as described in claim 1, 2, or 3, characterized in that: Depending on the type of mission the satellite is to perform, multiple mission templates are preset, and users can select one or more templates according to their observation needs.

Images