Cooperative flight path planning method and system applied to low-altitude aircraft

Abstract

The invention provides a collaborative flight path planning method and system applied to low-altitude aircrafts, relates to the technical field of flight control of the low-altitude aircrafts, and aims to construct a three-dimensional dynamic flight environment model aiming at the problems that a low-altitude flight environment is complicated and multiple aircrafts are difficult to collaborate. Low-altitude area obstacle distribution, real-time weather and multi-aircraft task demand information are covered. Generating an initial cooperative flight path set based on the three-dimensional dynamic flight environment model and the aircraft performance parameters, performing cooperative conflict verification on the initial cooperative flight path set, detecting an overlapping region of preset flight paths of different aircrafts in a space-time dimension, generating a path adjustment instruction according to a verification result in combination with task priority ranking, and performing cooperative conflict verification on the path adjustment instruction. The trajectory with conflicts is corrected, safe and efficient cooperative flight of multiple low-altitude aircrafts is achieved, and the overall performance and task execution efficiency of the low-altitude aircrafts in a complex environment are improved.

Description

Technical Field

[0001] This invention relates to the field of flight control technology for low-altitude aircraft, and more specifically, to a cooperative flight path planning method and system for low-altitude aircraft. Background Technology

[0002] In the field of low-altitude flight, with the increasing number of low-altitude aircraft and the growing complexity of application scenarios, how to achieve safe and efficient collaborative flight of multiple low-altitude aircraft has become a critical issue that urgently needs to be addressed. Currently, most existing flight path planning methods focus on individual aircraft, considering only their own flight performance and simple environmental factors, such as the distribution of static obstacles, to plan flight paths. However, the low-altitude flight environment is highly dynamic and complex, containing numerous dynamically changing obstacles, such as sudden construction work or flocks of birds, and is significantly affected by real-time weather conditions. For example, severe weather such as strong winds, heavy rain, and low visibility can drastically alter the flight status and safety boundaries of aircraft. Furthermore, when multiple low-altitude aircraft perform different tasks within the same low-altitude area, the lack of an effective coordination mechanism can easily lead to conflicts in time and space between the independently planned paths of each aircraft, resulting in collision risks that seriously affect flight safety and limit the efficiency and flexibility of low-altitude aircraft in complex mission scenarios. Therefore, existing technologies cannot meet the collaborative flight requirements of low-altitude aircraft in complex and dynamic environments, necessitating an innovative collaborative flight path planning method to solve these problems. Summary of the Invention

[0003] In view of the aforementioned problems, and in conjunction with the first aspect of the present invention, embodiments of the present invention provide a cooperative flight path planning method for low-altitude aircraft, the method comprising:

[0004] A three-dimensional dynamic flight environment model is constructed, which includes obstacle distribution information, real-time meteorological information, and mission requirement information of multiple low-altitude aircraft in the low-altitude region.

[0005] Based on the three-dimensional dynamic flight environment model, and combined with the flight performance parameters of each low-altitude aircraft, multiple sets of initial cooperative flight paths are generated. Each path in the initial cooperative flight path set corresponds to a preset flight trajectory of a low-altitude aircraft.

[0006] The initial set of cooperative flight paths is subjected to cooperative conflict verification processing. The overlapping areas of the preset flight trajectories of different low-altitude aircraft in the time and space dimensions are detected to obtain the cooperative conflict verification results.

[0007] Based on the collaborative conflict verification results and the task priority ranking of multiple low-altitude aircraft, a path adjustment command is generated. The path adjustment command is used to correct the preset flight trajectories that have conflicts, so as to realize the collaborative flight of multiple low-altitude aircraft.

[0008] Furthermore, embodiments of the present invention also provide a cooperative flight path planning system for low-altitude aircraft, characterized in that it includes:

[0009] A processor; a machine-readable storage medium for storing machine-executable instructions of the processor; wherein the processor is configured to execute the aforementioned cooperative flight path planning method for low-altitude aircraft by executing the machine-executable instructions.

[0010] In another aspect, embodiments of the present invention also provide a computer program product, the computer program product including machine-executable instructions, the machine-executable instructions being stored in a computer-readable storage medium, a processor of a computer device reading the machine-executable instructions from the computer-readable storage medium, the processor executing the machine-executable instructions, causing the computer device to execute the above-described cooperative flight path planning method applied to low-altitude aircraft.

[0011] Based on the above, a three-dimensional dynamic flight environment model is constructed, incorporating obstacle distribution information, real-time meteorological information, and mission requirements information for multiple low-altitude aircraft. This model, combined with the flight performance parameters of each low-altitude aircraft, generates multiple sets of initial cooperative flight paths. Taking into full account the characteristics and mission requirements of different aircraft, the initial cooperative flight path sets undergo cooperative conflict verification. This allows for timely and accurate detection of overlapping areas in the time and spatial dimensions of preset flight trajectories of different low-altitude aircraft, effectively avoiding potential collision risks. Based on the cooperative conflict verification results, path adjustment commands are generated by prioritizing the missions of multiple low-altitude aircraft. This intelligently and flexibly corrects conflicting preset flight trajectories, achieving efficient cooperative flight of multiple low-altitude aircraft while ensuring flight safety. This significantly improves the overall flight performance and mission execution efficiency of low-altitude aircraft in complex dynamic environments. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the execution flow of the cooperative flight path planning method for low-altitude aircraft provided in an embodiment of the present invention.

[0013] Figure 2 This is a schematic diagram of exemplary hardware and software components of a cooperative flight path planning system for low-altitude aircraft provided in an embodiment of the present invention. Detailed Implementation

[0014] The present invention will now be described in detail with reference to the accompanying drawings. Figure 1 This is a flowchart illustrating a cooperative flight path planning method for low-altitude aircraft provided in one embodiment of the present invention. The following is a detailed description of this cooperative flight path planning method for low-altitude aircraft.

[0015] Step S110: Construct a three-dimensional dynamic flight environment model, which includes obstacle distribution information in the low-altitude area, real-time meteorological information, and mission requirement information of multiple low-altitude aircraft.

[0016] In this embodiment, a low-altitude flight area consisting of a city's central business district and surrounding areas is used as the application scenario. Within this low-altitude flight area, there are multiple low-altitude aircraft performing different tasks, including aircraft A for urban express delivery, aircraft B for emergency medical supplies transportation, and aircraft C for environmental monitoring.

[0017] Step S111: Obtain basic environmental data for the low-altitude area, including terrain data, fixed obstacle data, real-time meteorological monitoring data, and mission parameter data of multiple low-altitude aircraft.

[0018] In this application scenario, the first step is to acquire basic environmental data. Topographic data is retrieved from a regional topographic mapping database, covering information such as surface elevation, slope, and aspect of the city's central business district and surrounding areas. Fixed obstacle data is collected through multiple channels, including building databases from urban planning departments, power tower data from power facility management departments, and communication base station data from communication management departments, encompassing relevant information on various buildings, power towers, and communication towers. Real-time meteorological monitoring data is provided by multiple meteorological monitoring stations deployed in the area, including real-time changes in wind speed, wind direction, temperature, and humidity. Mission parameter data for multiple low-altitude aircraft is provided by their respective mission scheduling centers. For example, aircraft A's mission parameters include the starting and ending points of a delivery package, the estimated start and end time windows, and the weight and volume of the goods to be delivered; aircraft B's mission parameters include the starting point of emergency medical supplies transport, the location of the target hospital, the latest required delivery time, and the weight of the supplies; and aircraft C's mission parameters include the starting coordinates of environmental monitoring, the planning requirements of the monitoring route, the time interval for data collection, and the mission duration.

[0019] Step S112: Perform three-dimensional modeling processing on the terrain data to generate a three-dimensional terrain model, and mark the areas of elevation change and terrain undulation features in the three-dimensional terrain model.

[0020] After acquiring the terrain data, it is processed into a 3D model. The elevation information in the terrain data is gridded according to a certain resolution, with each grid cell corresponding to an elevation value. Based on these gridded elevation data, a preliminary terrain framework for the region is constructed using 3D modeling software. Subsequently, the elevation differences between grid cells are analyzed, and continuous areas with elevation changes exceeding a set threshold are marked as areas of elevation variation, such as the hilly area surrounding the city's central business district. Simultaneously, by calculating parameters such as the curvature and slope change rate of the terrain surface, areas with significant terrain undulations, such as areas with valleys and ridges, are identified and marked accordingly in the 3D terrain model.

[0021] Step S113: Classify the fixed obstacle data and add corresponding obstacle 3D models to the terrain 3D model according to the type and height parameters of the obstacles to form obstacle sub-models containing obstacle distribution information.

[0022] The collected data on fixed obstacles is diverse and requires initial classification. Building obstacles are categorized by use into commercial buildings, residential buildings, industrial buildings, etc.; power facility obstacles are categorized into high-voltage transmission towers, substation ancillary facilities, etc.; communication tower obstacles are categorized into mobile communication base station towers, radio and television transmission towers, etc.; and natural obstacles are categorized into isolated hills, large groups of trees, etc. After classification, a corresponding 3D model template is selected for each type of obstacle.

[0023] Step S1131: Extract information from each obstacle entry in the fixed obstacle data to obtain the obstacle's location coordinates, bottom area parameters, height parameters, and obstacle type identifier.

[0024] For each obstacle entry, information is extracted one by one. Taking a commercial building in the city's central business district as an example, its precise location coordinates are extracted from the fixed obstacle data. These location coordinates are based on the city's unified coordinate system. The base area parameter includes the coordinates of each vertex of the building's outer contour at the base. These coordinates can be used to calculate the length, width, and other dimensions of the building's base. The height parameters are the building's eaves height and ridge height. The obstacle type is identified as "commercial building." Similarly, for a high-voltage transmission tower in the area, its location coordinates, base area parameter, total tower height parameter, and type identifier "Power Facility - High-Voltage Transmission Tower" are extracted.

[0025] Step S1132: Based on the obstacle type identifier, classify the obstacles into building obstacles, power facility obstacles, communication tower obstacles, and natural obstacles, and establish an obstacle classification list.

[0026] Based on the extracted obstacle type identifiers, all obstacles are classified. Those identified as commercial buildings, residential buildings, industrial buildings, etc., are classified as building obstacles; those identified as high-voltage transmission towers, substation ancillary facilities, etc., are classified as power facility obstacles; those identified as mobile communication base station towers, radio and television transmission towers, etc., are classified as communication tower obstacles; and those identified as isolated hills, large groups of trees, etc., are classified as natural obstacles. After organizing the classification results, an obstacle classification list containing all obstacle entries and their corresponding categories is created.

[0027] Step S1133: Select the corresponding 3D model template for different types of obstacles. Use a cuboid combination model template for building obstacles, a cylinder and cone combination model template for power facility obstacles, a slender cylinder superimposed model template for communication tower obstacles, and an irregular polygon extrusion model template for natural obstacles.

[0028] Based on the obstacle classification list, corresponding 3D model templates are matched for different types of obstacles. For architectural obstacles, which are mostly combinations of regular geometric shapes, a cuboid combination model template is used. For example, a commercial building can have a large cuboid as the main structure, with different functional areas on top stacked with cuboids of different sizes. For power facility obstacles, high-voltage transmission towers, whose tower bodies are mostly cylindrical structures, with the insulators and cable supports at the top considered as conical structures, a combination model template of cylinders and conicals is used. Communication tower obstacles typically have slender tower bodies and may have platforms at different heights; a slender cylindrical stacking model template is used, formed by stacking multiple slender cylinders of different diameters from top to bottom. For natural obstacles, isolated hills, with their irregular shapes, an irregular polygon extrusion model template is used. First, an irregular polygon is constructed based on the outline of the hill's base, and then it is extruded vertically according to elevation changes.

[0029] Step S1134: Based on the position coordinates of the obstacle, calculate the corresponding projection coordinates of the position coordinates in the terrain 3D model, and place the selected 3D model template at the projection coordinate position of the terrain 3D model.

[0030] For each obstacle, a coordinate transformation calculation is performed based on its location coordinates and the coordinate system used by the 3D terrain model to obtain its corresponding projected coordinates in the 3D terrain model. For example, after the location coordinates of a commercial building are transformed, its projected coordinates in the 3D terrain model are located within a specific grid cell of the city's central business district. The selected building-type cuboid combination model template is then precisely placed at the corresponding position in the 3D terrain model according to these projected coordinates.

[0031] Step S1135: Based on the bottom footprint parameters of the obstacle, calculate the required length and width dimensions of the bottom of the 3D model template, and adjust the bottom length and width of the 3D model template so that the bottom coverage of the 3D model is consistent with the actual bottom footprint of the obstacle.

[0032] Taking this commercial building as an example, based on the extracted base area parameters, the actual length and width of the building's base are determined by calculating the distance between the coordinates of its outer contour vertices. Then, according to the scale of the terrain 3D model, the actual length and width are converted into model dimensions, and the length and width of the bottom of the cuboid composite model template are adjusted so that the adjusted bottom coverage of the model matches the actual base area of ​​the commercial building in the terrain 3D model.

[0033] Step S1136: Calculate the required height stretch of the three-dimensional model template according to the height parameters of the obstacle, and stretch the height of the three-dimensional model template so that the height of the three-dimensional model matches the actual height parameters of the obstacle.

[0034] Based on the eaves and ridge height parameters of the commercial building, and combined with the elevation benchmark of the 3D terrain model, the required stretching height of the model template is calculated. The main body of the cuboid composite model template is stretched according to the stretching amount corresponding to the eaves height. For the protruding part at the top, additional stretching is performed according to the difference between the ridge height and the eaves height, so that the final height of the 3D model is consistent with the actual height parameters of the commercial building.

[0035] Step S1137: After completing the construction of a 3D model of a single obstacle, measure the spatial distance between the 3D model and the surrounding 3D obstacle models that have been constructed. Confirm that the spatial distance is greater than the preset model construction interval threshold, and then add obstacle type labels and height attribute labels to the 3D model.

[0036] After the 3D model of a single obstacle is built, its spatial distance to other existing obstacle 3D models is measured. Taking the newly built commercial building 3D model as an example, the shortest straight-line distance between it and the adjacent residential building 3D model and a nearby power tower 3D model is measured. If these distances are all greater than the preset model building interval threshold, it indicates that the model placement is reasonable and there are no issues with model overlap or insufficient spacing. Then, a "Building Type - Commercial Building" type label and corresponding eaves height and ridge height attribute labels are added to the commercial building 3D model.

[0037] Step S1138: Repeat the above steps to complete the construction of the three-dimensional models of all fixed obstacles, integrate all obstacle three-dimensional models with the terrain three-dimensional model, extract the obstacle position, height and type information from the integrated model, and form an obstacle sub-model containing obstacle distribution information.

[0038] Following the steps outlined above, construct 3D models of all fixed obstacles in the city's central business district and surrounding areas. After completion, integrate all obstacle 3D models with the previously generated terrain 3D model to ensure accurate spatial correspondence between the obstacle and terrain models. Once integrated, extract the location coordinates, height parameters, and type identifiers for each obstacle from the integrated model. Organize this information according to a specific format to form an obstacle sub-model containing obstacle distribution information.

[0039] Step S114: Perform time-series analysis on the real-time meteorological monitoring data, extract wind speed change information, wind direction change information and airflow disturbance information from the meteorological data, and construct a meteorological dynamic change model as a carrier of real-time meteorological information.

[0040] The acquired real-time meteorological monitoring data changes continuously over time, requiring time-series analysis. For wind speed data, the trend of its magnitude changes over different time periods is analyzed, such as wind speed variations in the morning, noon, and evening, to extract wind speed change information. Similarly, for wind direction data, its time-varying patterns are analyzed, such as the deflection angle and duration of wind direction, to extract wind direction change information. For airflow disturbance information, high-frequency fluctuations in wind speed and direction are analyzed; for example, sudden increases or decreases in wind speed within a short period and irregular oscillations in wind direction are considered airflow disturbances. Based on the extracted wind speed change information, wind direction change information, and airflow disturbance information, a dynamic meteorological change model is constructed. This dynamic model uses a time axis as a reference, associating and storing meteorological information from different moments, and can reflect the dynamic changes in meteorological conditions in the region in real time.

[0041] Step S115: Analyze the mission parameter data of the multiple low-altitude aircraft, extract the mission start coordinates, mission end coordinates, mission execution time window and mission objective requirements of each low-altitude aircraft, and generate a mission requirement list as a carrier of mission requirement information.

[0042] The mission parameter data of multiple low-altitude aircraft is analyzed and processed. For aircraft A, the following are extracted from its mission parameter data: the starting coordinates of the express delivery (located in a city's express sorting center), the destination coordinates (multiple different customer delivery addresses), the mission execution time window (from a certain time in the morning to a certain time at noon), and the mission objective (goods delivered intact and on time). For aircraft B, the following are extracted: the starting point coordinates of emergency medical supplies (a medical supplies warehouse), the location coordinates of the target hospital, the latest required delivery time (forming the end time of the mission execution time window, with the start time being the current time), and the mission objective (fast and safe transportation of supplies). For aircraft C, the following are extracted: the starting coordinates of environmental monitoring, the coordinates of multiple waypoints along the monitoring route (which can be considered as multiple intermediate endpoint coordinates), the duration of the monitoring mission (forming the mission execution time window), and the mission objective (collecting valid environmental data at set time intervals). After organizing the above extracted information, a mission requirement list is generated, with the mission information of each aircraft as an entry in the list.

[0043] Step S116: Extract the spatial coordinate reference from the obstacle sub-model, the timestamp reference from the meteorological dynamic change model, and the task coordinates and time information from the task requirement list.

[0044] The spatial coordinate reference used during the construction of the obstacle sub-model is extracted. This spatial coordinate reference is consistent with the unified urban coordinate system and includes information such as the coordinate origin, coordinate axis direction, and coordinate units. The timestamp reference for data records is extracted from the meteorological dynamic change model, including the start time of the timestamp and the time interval unit (e.g., one data point per minute). The task coordinate information, such as the start and end coordinates, of each aircraft task, as well as the time information, such as the start and end times of the task execution time window, are extracted from the task requirement list.

[0045] Step S117: Compare the spatial coordinate reference of the obstacle sub-model with the task coordinates of the task requirement list, calculate the coordinate deviation value, and if the coordinate deviation value exceeds the preset coordinate deviation threshold, adjust the task coordinates of the task requirement list to be consistent with the spatial coordinate reference of the obstacle sub-model.

[0046] The spatial coordinate reference of the obstacle sub-model is compared with the starting coordinates of Aircraft A (the express sorting center coordinates) in the task requirements list. The theoretical coordinate value of the task coordinates under the spatial coordinate reference of the obstacle sub-model is calculated using a coordinate transformation formula, and then compared with the actual coordinate values ​​recorded in the task requirements list to obtain the coordinate deviation value. If the coordinate deviation value exceeds a preset coordinate deviation threshold, it indicates a significant difference between the coordinate system used for the task coordinates and the spatial coordinate reference of the obstacle sub-model. The task coordinates in the task requirements list need to be adjusted to convert them to coordinate values ​​under the spatial coordinate reference of the obstacle sub-model. This comparison and adjustment operation is performed on all task coordinates in the task requirements list.

[0047] Step S118: Compare the timestamp reference of the meteorological dynamic change model with the task execution time window of the task requirement list, calculate the time deviation value, and if the time deviation value exceeds the preset time deviation threshold, adjust the timestamp of the meteorological dynamic change model to be consistent with the time reference of the task requirement list.

[0048] The timestamp reference of the meteorological dynamic change model is compared with the mission execution time window of aircraft B in the mission requirements list (start time is the current time, end time is the latest required delivery time). The timestamp reference of the meteorological dynamic change model may use a standard time format, while the time information in the mission requirements list may have issues such as time zone conversion or recording errors. The timestamp corresponding to the start time of the mission execution time window under the timestamp reference of the meteorological dynamic change model is calculated and compared with the timestamp corresponding to the start time recorded in the mission requirements list to obtain the time deviation value. If the time deviation value exceeds the preset time deviation threshold, the timestamp of the meteorological dynamic change model is adjusted to make its time reference consistent with the time reference of the mission requirements list, for example, by uniformly converting it to Coordinated Universal Time (UTC) or local standard time.

[0049] Step S119: After completing the coordinate and time adjustment, re-verify the data correlation of the obstacle sub-model, the meteorological dynamic change model and the task requirement list, confirm that the deviation of each part of the data in the spatial coordinate and time dimensions is within the preset threshold range, and then perform data fusion processing on the three to generate a complete three-dimensional dynamic flight environment model.

[0050] After completing the coordinate and time adjustments, the data correlation between the obstacle sub-model, the meteorological dynamic change model, and the task requirement list is re-verified. A destination coordinate of aircraft A is randomly selected from the task requirement list, and its spatial location within the obstacle sub-model is checked (i.e., whether the location is an accessible ground position, not inside an obstacle). Wind speed and direction data from the meteorological dynamic change model corresponding to a specific moment within the mission execution time window of aircraft B are selected, and their accuracy in reflecting the meteorological conditions of the area at that moment is checked. It is confirmed that the deviations of each data point in spatial coordinates are less than preset coordinate deviation thresholds, and the deviations in the time dimension are less than preset time deviation thresholds. Subsequently, the three data points are fused. The task coordinates and time information from the task requirement list are associated with the spatial locations and time nodes of the terrain 3D model and the obstacle sub-model. Simultaneously, the meteorological information from the meteorological dynamic change model is superimposed onto the 3D model according to time and spatial location, forming a complete 3D dynamic flight environment model.

[0051] Step S1110: At preset time intervals, reacquire the basic environmental data, repeat the above coordinate and time verification and adjustment steps, and update the obstacle distribution information, real-time meteorological information and mission requirement information in the three-dimensional dynamic flight environment model.

[0052] To ensure the timeliness of the 3D dynamic flight environment model, a preset time interval is set. At each preset time interval, basic environmental data is retrieved from various data sources, including the latest terrain data (if there are new terrain change projects in the area), fixed obstacle data (if new buildings are completed or old obstacles are removed), real-time weather monitoring data (to obtain the latest weather changes), and mission parameter data for multiple low-altitude aircraft (there may be new mission assignments or adjustments). Then, the coordinate and time verification and adjustment steps S112 to S119 are repeated to update the obstacle distribution information (adding new obstacle models or removing disappeared obstacle models), real-time weather information (updating the latest wind speed, wind direction, and other data), and mission requirement information (adding new missions or modifying mission parameters) in the 3D dynamic flight environment model.

[0053] Step S120: Based on the three-dimensional dynamic flight environment model and combined with the flight performance parameters of each low-altitude aircraft, generate multiple sets of initial cooperative flight paths. Each path in the initial cooperative flight path set corresponds to a preset flight trajectory of a low-altitude aircraft.

[0054] After constructing the three-dimensional dynamic flight environment model, based on this model and combined with the flight performance parameters of each low-altitude aircraft, the initial set of cooperative flight paths is generated. For aircraft A, B, and C, the impact of their flight performance on the path is considered, generating multiple possible path combinations. Each combination includes a preset flight trajectory for each aircraft, and these trajectories should avoid obvious conflicts as much as possible during the initial planning stage.

[0055] Step S121: Obtain the flight performance parameters of each low-altitude aircraft, including maximum flight speed, maximum climb altitude, endurance parameters, and wind resistance parameters.

[0056] Flight performance parameters are obtained from the technical manuals or aircraft management systems provided by the manufacturers of each low-altitude aircraft. Aircraft A's maximum speed is its maximum level flight speed under standard atmospheric conditions; its maximum climb altitude is its highest achievable altitude; its endurance parameters include the longest flight time and maximum flight distance on a full charge; and its wind resistance parameters include the maximum tailwind speed, maximum headwind speed, and maximum crosswind speed it can withstand. Aircraft B, as an emergency transport aircraft, has a higher maximum speed than Aircraft A, and its maximum climb altitude is comparable to or higher than Aircraft A's. Its endurance parameters are determined based on its battery capacity and power system efficiency, and its wind resistance parameters also have corresponding technical specifications. Aircraft C, as an environmental monitoring aircraft, typically has a slower flight speed, with a maximum speed lower than the previous two. Its maximum climb altitude is set according to monitoring requirements, its endurance parameters need to meet the requirements of long-term aerial monitoring, and its wind resistance parameters are determined based on its fuselage weight and stability design.

[0057] Step S122: Extract the mission start coordinates, mission end coordinates, and mission execution time window corresponding to each low-altitude aircraft from the three-dimensional dynamic flight environment model.

[0058] Based on a 3D dynamic flight environment model, key coordinates and time information relevant to the mission are extracted for each low-altitude aircraft. For aircraft A, the starting coordinates (adjusted to the coordinates of the express sorting center under the model's spatial coordinate datum), ending coordinates (coordinates of multiple customer delivery addresses), and mission execution time window (from a certain time in the morning to a certain time at noon) for its express delivery are extracted from the model's mission requirement information. For aircraft B, the starting point coordinates (coordinates of the medical supply warehouse), the location coordinates of the target hospital, and the mission execution time window (from the current time to the latest required delivery time) for emergency medical supply transportation are extracted. For aircraft C, the starting coordinates of environmental monitoring, the coordinates of multiple monitoring points along the route (as intermediate endpoint coordinates), and the mission execution time window (the start and end times corresponding to the mission duration) are extracted.

[0059] Step S123: Based on the coordinates of the mission start point and the mission end point, and combined with the terrain 3D model and obstacle sub-model in the 3D dynamic flight environment model, several candidate paths with no risk of terrain and obstacle collisions are initially planned.

[0060] Taking aircraft A as an example, preliminary path planning is performed based on its mission starting point coordinates (express sorting center) and one of its destination coordinates (a customer's delivery address), combined with the terrain 3D model and obstacle sub-model in the 3D dynamic flight environment model. Using a path search algorithm, unsuitable flight areas (such as steep slopes) in the terrain 3D model and areas with terrain undulations are avoided, while also avoiding the space occupied by all obstacle 3D models in the obstacle sub-model. By changing the positions of intermediate nodes, multiple different paths are generated. These paths all meet the condition of being from the starting point to the destination without the risk of terrain or obstacle collisions, and are considered candidate paths for aircraft A. The same preliminary planning is performed on the other destination coordinates of aircraft A, as well as all destination coordinates of aircraft B and C, resulting in multiple candidate paths for each.

[0061] Step S124: For each candidate path, combine the flight performance parameters and the meteorological dynamic change model in the three-dimensional dynamic flight environment model to analyze the impact of wind speed and wind direction on the flight speed and energy consumption of the low-altitude aircraft, and calculate the expected flight time and expected energy consumption parameters for each candidate path.

[0062] For a candidate path of aircraft A, an analysis is conducted combining its flight performance parameters and a meteorological dynamics model. Wind speed and direction data for each spatial location traversed by the candidate path within the mission execution time window are extracted from the meteorological dynamics model. The angle between the wind direction and the path direction is analyzed. When the angle is 0 degrees (tailwind), the aircraft's actual flight speed is the sum of its maximum flight speed and the wind speed, but cannot exceed the upper limit of its maximum flight speed. When the angle is 180 degrees (headwind), the actual flight speed is the difference between the maximum flight speed and the wind speed. If the difference is lower than the minimum safe flight speed, the aircraft flies at the minimum safe flight speed. For other angles, the wind speed is decomposed into components along the path direction and perpendicular to the path direction. The component along the path direction affects the flight speed, while the component perpendicular to the path direction mainly affects flight attitude stability, but here the primary consideration is its impact on speed. Based on the actual flight speed and path length at different locations, the time to pass through each location is calculated, and these are summed to obtain the estimated flight time for the candidate path. Simultaneously, based on flight speed, flight time, and the energy consumption model of the aircraft's propulsion system (considering energy consumption rates at different speeds), and combined with the influence of wind speed on flight drag (drag increases and energy consumption increases when facing headwinds; drag decreases and energy consumption decreases when facing tailwinds), the expected energy consumption parameters for this candidate path are calculated. The above-mentioned expected flight time and expected energy consumption parameters are calculated for all candidate paths of aircraft A and for each candidate path of aircraft B and C.

[0063] Step S1241: Divide the candidate path into multiple path segments according to a preset distance interval. Each path segment corresponds to a sub-region. Record the start and end coordinates of each sub-region and calculate the distance of each sub-region.

[0064] A candidate path for aircraft A is segmented according to preset distance intervals. For example, starting from the starting coordinates, a segment point is taken at certain straight-line distances until the ending coordinates, thus dividing the entire candidate path into multiple continuous path segments. Each path segment corresponds to a sub-region in the 3D dynamic flight environment model, and the starting coordinates (segment point coordinates) and ending coordinates (next segment point coordinates) of that sub-region are recorded. The distance of each sub-region is obtained by calculating the straight-line distance between the starting and ending coordinates.

[0065] Step S1242: Extract wind speed and wind direction data corresponding to each sub-region from the meteorological dynamic change model, determine the magnitude of wind speed and the angle of wind direction in each sub-region, and calculate the angle between the wind direction and the extension direction of the candidate path in that sub-region.

[0066] For each sub-region, wind speed and direction data are extracted from the meteorological dynamics model at the time the aircraft is expected to pass through that sub-region. Wind speed data includes the numerical value of the wind speed, and wind direction data includes the angle of the wind direction relative to true north. Simultaneously, the angle of the candidate path extension direction relative to true north within that sub-region is determined. The angle between the wind direction and the path extension direction is obtained by calculating the difference between the wind direction angle and the path extension direction angle.

[0067] Step S1243: Based on the maximum flight speed and wind resistance parameters in the flight performance parameters of the low-altitude aircraft, and combined with the wind speed magnitude and wind direction angle of the sub-region, calculate the component of wind speed in the flight direction.

[0068] Based on the aircraft's maximum flight speed and wind resistance parameters (such as maximum headwind speed), the wind speed magnitude and wind direction angle of the sub-region are considered. If the wind direction angle is 0 degrees (tailwind), the wind speed component in the flight direction is the wind speed magnitude; if the angle is 180 degrees (headwind), the component is the negative value of the wind speed magnitude; if the angle is 90 degrees or 270 degrees (crosswind), the component is 0; for other angles, the wind speed component in the flight direction is calculated using trigonometric functions. Simultaneously, it is ensured that the absolute value of this component does not exceed the aircraft's wind resistance parameters; if it does, the corresponding limit of the wind resistance parameters is used as the component value.

[0069] Step S1244: When the wind direction angle is less than 90 degrees, the actual flight speed is the sum of the maximum flight speed and the component of the wind speed in the flight direction; when the wind direction angle is greater than 90 degrees, the actual flight speed is the difference between the maximum flight speed and the component of the wind speed in the flight direction.

[0070] The calculation method for actual flight speed is determined based on the magnitude of the wind direction angle. When the wind direction angle is less than 90 degrees, it is considered a tailwind or cross-tailwind, and the component of wind speed in the flight direction is positive. The actual flight speed equals the maximum flight speed plus this component value. However, it is necessary to check whether the calculated actual flight speed exceeds the aircraft's maximum flight speed. If it does, the maximum flight speed is used as the actual flight speed. When the wind direction angle is greater than 90 degrees, it is considered a headwind or cross-headwind, and the component of wind speed in the flight direction is negative or a small positive value. The actual flight speed equals the maximum flight speed plus this component value (i.e., subtracting the absolute value of the component). If the calculated actual flight speed is lower than the aircraft's minimum safe flight speed, the minimum safe flight speed is used as the actual flight speed.

[0071] Step S1245: Calculate the difference between the actual flight speed and the preset minimum safe flight speed. If the actual flight speed is lower than the minimum safe flight speed, adjust the actual flight speed to the minimum safe flight speed.

[0072] After calculating the actual flight speed for each sub-region, it is compared with the preset minimum safe flight speed. If the actual flight speed is lower than the minimum safe flight speed, it indicates that the flight conditions may adversely affect the stability or controllability of the aircraft, and the actual flight speed needs to be adjusted to the minimum safe flight speed. For example, in strong headwinds, the calculated actual flight speed may be lower than the minimum safe flight speed. In this case, the speed should be adjusted to the minimum safe flight speed, and the aircraft should pass through the sub-region at this speed.

[0073] Step S1246: Calculate the time required for the low-altitude aircraft to pass through each sub-region based on the distance and the corresponding actual flight speed. Add up the passing times of all sub-regions to obtain the estimated flight time of the candidate path.

[0074] For each sub-region, divide the distance of that sub-region by its corresponding actual flight speed to obtain the time required to traverse that sub-region. Sum the traversal times of all sub-regions, and add the takeoff and landing times (if not included in the path segment) to obtain the estimated flight time for the entire candidate path.

[0075] Step S1247: Based on the endurance parameters of the low-altitude aircraft, combined with the actual flight speed, wind speed, and wind resistance parameters of each sub-region, calculate the energy consumption of the low-altitude aircraft in each sub-region using a predefined, dimensionally consistent energy consumption calculation model. The energy consumption calculation model ensures that the energy consumption obtained after the input parameters are calculated has a clear energy dimension. Add up the energy consumption of all sub-regions to obtain the expected energy consumption parameters of the candidate path.

[0076] Based on the aircraft's endurance parameters (such as battery capacity), and combined with the actual flight speed, wind speed, and wind resistance parameters of each sub-region, a predefined energy consumption calculation model is used to calculate energy consumption. This model considers the relationship between actual flight speed and energy consumption rate (generally, higher speed results in a higher energy consumption rate), the impact of wind speed on flight drag (greater drag results in a higher energy consumption rate), and energy consumption compensation under wind resistance parameter limitations. The model's input parameters include actual flight speed (unit: distance / time), wind speed (unit: distance / time), and sub-region distance (unit: distance). Dimensional analysis ensures that the combined calculation of these parameters yields the energy consumption (unit: energy). For example, energy consumption can be expressed as the product of energy consumption rate (energy / distance) and sub-region distance, where the energy consumption rate is related to the square of the actual flight speed and the drag coefficient caused by wind speed. After calculating the energy consumption for each sub-region, the values ​​are summed to obtain the predicted energy consumption parameters for the candidate path.

[0077] Step S1248: Compare the calculated expected energy consumption parameters with the maximum endurance energy consumption of the low-altitude aircraft. If the expected energy consumption parameters exceed the maximum endurance energy consumption, mark the candidate path as an invalid path.

[0078] The projected energy consumption parameters of the candidate path are compared with the maximum endurance energy consumption of aircraft A (determined by the energy consumption corresponding to the battery capacity or maximum flight distance in the endurance parameters). If the projected energy consumption parameter exceeds the maximum endurance energy consumption, it means that the aircraft cannot complete the flight on its own power, and the candidate path is marked as an invalid path and will not be considered in subsequent steps.

[0079] Step S1249: Compare the estimated flight time with the preset maximum tolerance time range. If the estimated flight time exceeds the maximum tolerance time range, mark the candidate path as an invalid path.

[0080] The estimated flight time of a candidate path is compared with the duration of the mission execution time window (i.e., the maximum tolerable time range). If the estimated flight time exceeds the maximum tolerable time range, it indicates that the mission cannot be completed within the specified time, and the candidate path is also marked as an invalid path.

[0081] Step S125: Based on the mission execution time window, select candidate paths whose estimated flight time is within the mission execution time window to form a set of valid candidate paths.

[0082] For aircraft A, paths whose estimated flight time falls within the mission execution time window (from a certain time in the morning to a certain time at noon) are selected from all its candidate paths; these paths constitute the set of valid candidate paths for aircraft A. Similarly, for aircraft B, candidate paths whose estimated flight time falls within its mission execution time window (from the current time to the latest required delivery time) are selected, forming the set of valid candidate paths. Aircraft C is also selected according to its mission execution time window to obtain its set of valid candidate paths.

[0083] Step S126: Smooth each path in the set of valid candidate paths, eliminate sharp turning nodes in the path, calculate the curvature change value after path smoothing, confirm that the curvature change value meets the flight control requirements of low-altitude aircraft, and obtain the smoothed candidate path.

[0084] A path from the set of valid candidate paths for aircraft A is smoothed. Sharp turning nodes on the path can cause the aircraft to experience significant centrifugal forces, affecting flight stability and passenger comfort (if manned). For unmanned logistics aircraft, it may also increase energy consumption and control difficulty. A curve fitting algorithm is used to smooth the turning nodes in the path, for example, connecting nodes connected by broken lines with smooth curves such as circular arcs or Bézier curves. After processing, the curvature values ​​at each point on the path are calculated, and the curvature changes are analyzed to obtain the curvature change values. The curvature change values ​​are compared with the flight control requirements of aircraft A (such as the maximum permissible rate of curvature change). If the requirements are met, the smoothed path is retained; otherwise, the smoothing parameters are readjusted and the process is repeated until the curvature change values ​​meet the requirements, resulting in a smoothed candidate path. The above smoothing process is performed on all paths in the set of valid candidate paths.

[0085] Step S127: Randomly select one path from the smoothed candidate paths of each low-altitude aircraft to form a path combination, and extract the spatial coordinate sequence of the preset flight trajectories of all low-altitude aircraft in the path combination.

[0086] Randomly select one path from the smoothed candidate paths of aircraft A, one path from the smoothed candidate paths of aircraft B, and one path from the smoothed candidate paths of aircraft C to form a path combination. Extract the spatial coordinate sequence of the preset flight trajectory of aircraft A (including the starting coordinates, coordinates of each smoothed node, and the ending coordinates) from this combination. Similarly, extract the spatial coordinate sequences of the preset flight trajectories of aircraft B and aircraft C.

[0087] Step S128: Calculate the minimum straight-line distance between any two preset flight paths in the spatial coordinate sequence. If the minimum straight-line distance is greater than the preset preliminary planning safety distance, then the path combination is taken as a set of initial cooperative flight paths.

[0088] Calculate the straight-line distances between corresponding points on the spatial coordinate sequence of the preset flight trajectories of aircraft A and aircraft B in the above path combination, and find the minimum straight-line distance. Similarly, calculate the minimum straight-line distances between the preset flight trajectories of aircraft A and aircraft C, and aircraft B and aircraft C. If all these minimum straight-line distances are greater than the preset preliminary planning safety distance (set according to aircraft size, flight speed, and collision avoidance redundancy), it indicates that there is no significant risk of spatial overlap between the trajectories in this path combination, and this path combination is taken as a set of initial cooperative flight paths.

[0089] Step S129: If the minimum straight-line distance is less than or equal to the preset initial planning safety distance, then select a new path to form a new path combination, and repeat the above spatial distance calculation and judgment steps until multiple path combinations that meet the requirement of no obvious spatial overlap are selected as multiple initial cooperative flight path sets. Each initial cooperative flight path set contains the preset flight trajectories of a corresponding number of low-altitude aircraft.

[0090] If the minimum straight-line distance between the preset flight trajectories of aircraft A and aircraft B in a certain path combination is less than or equal to the initially planned safe distance, then this combination is abandoned. New path combinations are then randomly selected from the smoothed candidate paths of aircraft A, B, and C. The minimum straight-line distance between any two trajectories is calculated and judged again. This process is repeated until multiple sets (e.g., five, ten sets, etc.) of path combinations are selected that satisfy the condition that the minimum straight-line distance between the preset flight trajectories of all aircraft is greater than the initially planned safe distance. These combinations are then used as a set of multiple initial cooperative flight paths.

[0091] Step S130: Perform cooperative conflict verification processing on the initial cooperative flight path set, detect the overlapping areas of the preset flight trajectories of different low-altitude aircraft in the time and space dimensions, and obtain the cooperative conflict verification results.

[0092] After generating multiple sets of initial cooperative flight paths, each set needs to undergo cooperative conflict verification. This is done by analyzing the temporal and spatial relationships between the preset flight trajectories of different aircraft to detect any overlapping areas.

[0093] Step S131: Add a timeline marker to each preset flight trajectory in each set of initial cooperative flight paths. The timeline marker starts from the takeoff time of the low-altitude aircraft and ends at the expected time of arrival at the mission endpoint. The timeline is divided into multiple time slices according to preset time intervals, and the start and end times of each time slice are recorded.

[0094] Taking a set of initial coordinated flight paths as an example, a timeline marker is added to the preset flight trajectory of aircraft A. Based on its estimated flight time and the start time of the mission execution time window, the takeoff time (start time of the mission execution time window) and the estimated arrival time at the mission endpoint (takeoff time plus estimated flight time) are determined. The timeline from takeoff time to estimated arrival time is divided into multiple time slices according to preset time intervals (e.g., one slice every ten seconds). Each time slice has a start time and an end time. For example, the first time slice starts at the takeoff time and ends at the takeoff time plus ten seconds; the second time slice starts at the end time of the first, and so on. The same timeline markers and time slice divisions are applied to the preset flight trajectories of aircraft B and C in this path combination.

[0095] Step S132: Within each time slice, extract the set of spatial coordinate points corresponding to each preset flight trajectory. The set of spatial coordinate points includes multiple position coordinates of the low-altitude aircraft on the preset flight trajectory within the time slice, and record the three-dimensional parameters of each position coordinate.

[0096] For a pre-defined flight trajectory of aircraft A within a certain time slice, based on the start and end times of the time slice and the changes in aircraft A's flight speed, multiple position coordinates along the pre-defined flight trajectory traversed by aircraft A within that time slice are calculated. For example, if the time slice lasts for ten seconds, and the aircraft's flight speed varies within that slice, the ten seconds are divided into several smaller time intervals, and the flight distance for each smaller time interval is calculated, thereby determining multiple position coordinates. These coordinates form a set of spatial coordinate points, each containing three-dimensional parameters (longitude, latitude, and altitude). The spatial coordinate point sets are extracted for all time slices of aircraft A, as well as for aircraft B and C within each time slice.

[0097] Step S133: Calculate the spatial distance between the sets of spatial coordinate points of different preset flight trajectories within the same time slice, and calculate the straight-line distance between spatial coordinate points on any two different preset flight trajectories.

[0098] Within the same time slice, spatial distance is calculated for the preset sets of spatial coordinate points for the flight trajectories of aircraft A and aircraft B. A position coordinate is selected from the set of spatial coordinate points of aircraft A, and a position coordinate is selected from the set of spatial coordinate points of aircraft B; the straight-line distance between these two coordinates is calculated.

[0099] Step S1331: Select two different preset flight trajectories from the initial cooperative flight path set within the same time slice, and denot them as the first preset flight trajectory and the second preset flight trajectory, respectively.

[0100] Within the same time slice of a certain initial set of cooperative flight paths, the preset flight trajectory of aircraft A is selected as the first preset flight trajectory, and the preset flight trajectory of aircraft B is selected as the second preset flight trajectory.

[0101] Step S1332: Extract the set of spatial coordinate points of the first preset flight trajectory within the time slice, denoted as the first coordinate point set; extract the set of spatial coordinate points of the second preset flight trajectory within the time slice, denoted as the second coordinate point set.

[0102] Extract all position coordinates of the first preset flight trajectory (aircraft A) within the time slice to form a first set of coordinate points; extract all position coordinates of the second preset flight trajectory (aircraft B) within the time slice to form a second set of coordinate points.

[0103] Step S1333: Select a spatial coordinate point from the first set of coordinate points and denot it as the first coordinate point. The three-dimensional spatial coordinates of the first coordinate point include the first horizontal direction coordinate, the first vertical horizontal direction coordinate, and the first height direction coordinate.

[0104] The first spatial coordinate point is selected from the first set of coordinate points as the first coordinate point. The three-dimensional spatial coordinates of the first coordinate point include the first horizontal direction coordinate representing the east-west direction, the first vertical horizontal direction coordinate representing the north-south direction, and the first vertical direction coordinate representing the altitude.

[0105] Step S1334: Select a spatial coordinate point from the second set of coordinate points and denot it as the second coordinate point. The three-dimensional spatial coordinates of the second coordinate point include the second horizontal direction coordinate, the second vertical horizontal direction coordinate, and the second height direction coordinate.

[0106] Select the first spatial coordinate point from the second set of coordinate points as the second coordinate point. Its three-dimensional spatial coordinates include the second horizontal direction coordinate, the second vertical horizontal direction coordinate, and the second height direction coordinate.

[0107] Step S1335: Calculate the centerline distance between the first coordinate point and the second coordinate point, and record the calculated centerline distance and the corresponding three-dimensional spatial coordinate parameters of the first coordinate point and the second coordinate point.

[0108] Based on the three-dimensional spatial coordinate parameters of the first and second coordinate points, calculate the distance between their centers using the three-dimensional spatial distance calculation formula. Record this distance value and the corresponding three-dimensional coordinate parameters of the two coordinate points.

[0109] Step S1336: Select the next uncalculated spatial coordinate point from the first set of coordinate points, and repeat the above centerline distance calculation steps until all spatial coordinate points in the first set of coordinate points have completed the distance calculation with all spatial coordinate points in the second set of coordinate points.

[0110] Select the second uncalculated spatial coordinate point from the first set of coordinate points, and calculate the centerline distance between it and all spatial coordinate points in the second set of coordinate points in turn. Repeat this process until all spatial coordinate points in the first set of coordinate points have completed distance calculations with all spatial coordinate points in the second set of coordinate points.

[0111] Step S1337: Select two other uncombined preset flight paths from the initial set of cooperative flight paths as the new first preset flight path and the second preset flight path. Repeat the above distance calculation steps until the spatial coordinate points between all different preset flight paths in the same time slice have completed the centerline distance calculation.

[0112] Select the preset flight trajectories of aircraft A and aircraft C as the new first and second preset flight trajectories, and repeat the distance calculation process from steps S1332 to S1336. Then select the preset flight trajectories of aircraft B and aircraft C for calculation, until the spatial coordinate points between all different preset flight trajectories within the same time slice have completed the centerline distance calculation.

[0113] Step S134: Compare the calculated centerline distance with the preset safe distance threshold. If there are two spatial coordinate points with a centerline distance less than the safe distance threshold, record the start time, end time, and position coordinates of the two spatial coordinate points for the time slice. Determine that the preset flight trajectories corresponding to these two spatial coordinate points have a risk of spatial overlap within the time slice, and mark the time slice and the corresponding spatial coordinate point position as a conflict candidate area.

[0114] The calculated distance between the centers of any two spatial coordinate points is compared with a preset safety distance threshold (set based on aircraft size, flight speed, and collision avoidance safety margin). If the distance between the centers of two spatial coordinate points (such as a coordinate point of aircraft A and a coordinate point of aircraft B) is less than the safety distance threshold, the start time, end time, and position coordinates of the two coordinate points in the time slice are recorded. It is determined that the preset flight trajectories of aircraft A and B have a risk of spatial overlap within the time slice, and the time slice and the corresponding coordinate point position are marked as a candidate conflict area.

[0115] Step S135: After performing the above conflict detection processing on all time slices, count the number of conflict candidate regions in each initial cooperative flight path set, and record the time slice range and spatial coordinate range corresponding to each conflict candidate region. The time slice range includes the start time and end time, and the spatial coordinate range includes the three-dimensional parameter range of the position coordinates.

[0116] After performing the conflict detection process in step S134 on all time slices in a set of initial cooperative flight paths, the total number of conflict candidate regions in the set is counted. For each conflict candidate region, its corresponding time slice range (start time and end time) and spatial coordinate range (a cubic region determined according to the three-dimensional parameters of the conflict coordinate point, including a certain range around the coordinate point) are recorded in detail.

[0117] Step S136: Further analyze the conflict candidate regions, extract the time slice range and spatial coordinate range of adjacent conflict candidate regions, and determine whether the end time of the previous conflict candidate region is continuous with the start time of the next conflict candidate region, and whether the spatial coordinate range of the previous conflict candidate region overlaps with the spatial coordinate range of the next conflict candidate region.

[0118] Extract two adjacent conflict candidate regions. The end time of the first conflict candidate region is T1, and the start time of the second one is T2. Determine whether T2 is equal to T1. If so, the time is continuous. At the same time, determine whether there is an overlap between the spatial coordinate ranges of the first conflict candidate region (such as x1_min - x1_max, y1_min - y1_max, z1_min - z1_max) and those of the second one (x2_min - x2_max, y2_min - y2_max, z2_min - z2_max), that is, determine whether x1_min < x2_max and x2_min < x1_max, and similar conditions are satisfied in the y and z directions. If all are satisfied, the spatial ranges overlap.

[0119] Step S137: If the time is continuous and the spatial ranges overlap, then merge the corresponding conflict candidate regions into a continuous conflict region, and record the total start time, total end time, and total spatial coordinate range of the continuous conflict region.

[0120] If two adjacent conflict candidate regions meet the conditions of continuous time and overlapping spatial ranges, then merge them into a continuous conflict region. The total start time of the merged continuous conflict region is the start time of the previous conflict candidate region, the total end time is the end time of the latter conflict candidate region, and the total spatial coordinate range is the union of the spatial coordinate ranges of the two conflict candidate regions.

[0121] Step S138: According to the information of the conflict candidate regions and continuous conflict regions in each set of initial cooperative flight path sets, where the conflict candidate regions are the unmerged conflict candidate regions, sort out the identifiers of the initial cooperative flight path sets without conflicts, the identifiers of the initial cooperative flight path sets with conflicts, the time information and spatial information of the conflict regions. The time information includes the start time and end time, and the spatial information includes the position coordinate range, and generate a cooperative conflict verification result.

[0122] For each set of initial cooperative flight path sets, sort out the information of the unmerged conflict candidate regions and the merged continuous conflict regions. If there are no conflict candidate regions and continuous conflict regions in a certain set, mark it as an initial cooperative flight path set without conflicts and record its identifier. If there are conflict regions, mark it as an initial cooperative flight path set with conflicts, record its identifier and the time information (start time and end time) and spatial information (position coordinate range) of all conflict regions, and generate a cooperative conflict verification result.

[0123] Step S140: According to the cooperative conflict verification result, combined with the task priority sorting of multiple low-altitude aircraft, generate a path adjustment instruction, and the path adjustment instruction is used to correct the preset flight trajectories with conflicts to achieve the cooperative flight of multiple low-altitude aircraft.

[0124] Based on the results of the collaborative conflict verification, for the initial collaborative flight path set with conflicts, and in combination with the task priority ranking of multiple low-altitude aircraft, the aircraft whose paths need to be adjusted are determined, new flight trajectories are planned, and path adjustment instructions are generated to eliminate conflicts and achieve collaborative flight.

[0125] Step S141: Select the set of initial cooperative flight paths with conflicts from the cooperative conflict verification results, extract the conflict area information from each set of initial cooperative flight paths with conflicts, the conflict area information includes the time range and spatial range, determine the preset flight trajectory corresponding to the conflict area, and record it as the conflict trajectory.

[0126] From the collaborative conflict verification results, identify all initial collaborative flight path sets with conflicts. For each set corresponding to an identifier, extract information on all conflict regions (including candidate conflict regions and consecutive conflict regions). Each conflict region's information includes a time range (start and end times) and a spatial range (position coordinate range). Based on the aircraft involved in the conflict region, determine the corresponding preset flight trajectory, which is the conflict trajectory. For example, if a conflict region involves aircraft A and B, then the preset flight trajectories of aircraft A and B are both conflict trajectories.

[0127] Step S142: Obtain a mission priority ranking table for multiple low-altitude aircraft. The mission priority ranking table is formulated based on the urgency of the mission, the importance of the mission objective, and the mission execution period. Each low-altitude aircraft corresponds to a priority level, and the determination criteria for each priority level are recorded.

[0128] The task priority ranking table is formulated by the task management center based on the task situation. Aircraft B's task is emergency medical supplies transportation, which has the highest urgency level, the highest importance of its objective (related to life safety), and the shortest execution period; therefore, it has the highest priority level, determined by the criteria of "emergency medical transportation task, highest urgency level." Aircraft A's express delivery task has the next highest urgency and importance, with a medium priority level, determined by the criteria of "ordinary logistics task, medium urgency level." Aircraft C's environmental monitoring task has the lowest urgency and lowest priority level, determined by the criteria of "routine monitoring task, low urgency level."

[0129] Step S143: Extract the priority level and judgment criteria of the low-altitude aircraft corresponding to the conflict trajectory, compare the priority levels corresponding to different conflict trajectories, and record the comparison results.

[0130] For a given conflict zone, the conflict trajectories (trajectories of aircraft A and B) are analyzed. The priority level (medium) and determination criteria for aircraft A, and the priority level (highest) and determination criteria for aircraft B, are extracted. A comparison of their priority levels reveals that aircraft B has a higher priority than aircraft A.

[0131] Step S144: Extract the priority level of the low-altitude aircraft corresponding to each conflict trajectory, compare the priority levels based on the task priority sorting table, and determine the target low-altitude aircraft whose flight path needs to be adjusted from the low-altitude aircraft with conflict based on the comparison results.

[0132] Based on the task priority ranking table, the priority levels of aircraft A and B corresponding to the conflict trajectories are compared. Since aircraft B has a higher priority, aircraft A, which has a lower priority, is determined to be the target low-altitude aircraft whose flight path needs to be adjusted.

[0133] Step S145: For the conflict trajectory corresponding to the target low-altitude aircraft, extract the time range and spatial range of the conflict area. Combine the obstacle sub-model and the meteorological dynamic change model in the three-dimensional dynamic flight environment model to delineate a preset search range around the conflict area. The time range includes the start time and end time, and the spatial range includes the position coordinate range. The obstacle sub-model provides the position and height of the surrounding obstacles, and the meteorological dynamic change model provides the surrounding wind speed and wind direction.

[0134] For the collision trajectory of the target low-altitude aircraft A, the temporal range (T_start-T_end) and spatial range (X_min-X_max, Y_min-Y_max, Z_min-Z_max) of a certain collision area are extracted. Combining a 3D dynamic flight environment model, the position coordinates and altitude information of obstacles surrounding the collision area are obtained from the obstacle sub-model, and wind speed and direction data within the time range T_start-T_end are obtained from the meteorological dynamic change model. Based on the spatial range of the collision area, a preset search range is defined by extending a certain distance (e.g., several hundred meters) outwards; this preset search range is the area for finding alternative detour paths.

[0135] For example, step S1451: extract the start time, end time and corresponding spatial coordinate range of the conflict area in the conflict trajectory corresponding to the target low-altitude aircraft. The spatial coordinate range includes the maximum and minimum values ​​of the three-dimensional coordinates. Determine the three-dimensional boundary of the conflict area in three-dimensional space based on the spatial coordinate range. The three-dimensional boundary is composed of a three-dimensional polygon formed by the boundary coordinates.

[0136] Extract the start time T_s, end time T_e, and the maximum and minimum three-dimensional coordinates (X_max, X_min, Y_max, Y_min, Z_max, Z_min) of a conflict region within the collision trajectory of the target low-altitude aircraft A. Based on these maximum and minimum values, determine the three-dimensional boundary of the conflict region. This boundary is composed of a three-dimensional polygon (cube) with coordinates of eight vertices, each vertex being (X_max / Y_max / Z_max), (X_max / Y_max / Z_min), (X_max / Y_min / Z_max), (X_max / Y_min / Z_min), (X_min / Y_max / Z_max), (X_min / Y_max / Z_min), (X_min / Y_min / Z_max), (X_min / Y_min / Z_min), (X_min / Y_min / Z_max), (X_min / Y_min / Z_min).

[0137] Step S1452: Extract the position coordinates and height parameters of all obstacles within a preset range around the three-dimensional boundary of the conflict area from the obstacle sub-model of the three-dimensional dynamic flight environment model. The preset range is the range formed by extending a preset distance outward from the three-dimensional boundary. Mark the area occupied by the obstacle in the three-dimensional space as an impassable spatial area.

[0138] Based on the three-dimensional boundary of the conflict area, a preset range is formed by expanding outward by a predetermined distance (e.g., a certain distance in both the horizontal and vertical directions, and a certain range in the vertical direction). The position coordinates and height parameters of all obstacles (buildings, power towers, etc.) within this preset range are extracted from the obstacle sub-model. Based on this information, the area occupied by each obstacle in three-dimensional space is determined (e.g., a cubic area centered on the position coordinates, with the bottom area and height parameters determined). This area is marked as an impassable space.

[0139] Step S1453: Extract wind speed data, wind direction data, and airflow disturbance data from the meteorological dynamic change model of the three-dimensional dynamic flight environment model, within a preset range around the three-dimensional boundary of the conflict area, set wind speed threshold, wind direction stability threshold, and airflow disturbance threshold, and mark areas where the wind speed exceeds the wind speed threshold, the wind direction fluctuation exceeds the wind direction stability threshold, or the airflow disturbance exceeds the airflow disturbance threshold as severe weather areas unsuitable for flight.

[0140] Wind speed, wind direction, and airflow disturbance data within a preset range and time interval (T_s-T_e) in the conflict area are extracted from the meteorological dynamic change model. The wind speed threshold is set as the maximum permissible wind speed in the aircraft's wind resistance parameters; the wind direction stability threshold is the maximum permissible angle of wind direction change per unit time; and the airflow disturbance threshold is the maximum permissible amplitude of wind speed fluctuation per unit time. Areas where the wind speed exceeds the wind speed threshold, the wind direction fluctuation angle exceeds the wind direction stability threshold, or the airflow disturbance amplitude exceeds the airflow disturbance threshold are marked as severe weather areas unsuitable for flight.

[0141] Step S1454: Collect the three-dimensional coordinate ranges of conflict areas, impassable spatial areas, and severe weather areas unsuitable for flight, and integrate them into a set of prohibited areas. Record the boundary coordinates of each area in the set of prohibited areas.

[0142] The three-dimensional coordinate ranges of the conflict zone itself, the three-dimensional coordinate ranges of impassable spatial areas, and the three-dimensional coordinate ranges of areas unsuitable for flight due to severe weather are collected and integrated to form a set of prohibited areas. For each area in the set, its boundary coordinates (vertices of the 3D polygon) are recorded in detail.

[0143] Step S1455: Extract the preceding and following path nodes of the conflict area from the conflict trajectory. The preceding path node is the last valid coordinate point before the starting coordinate of the conflict area, and the following path node is the first valid coordinate point after the ending coordinate of the conflict area. Determine the three-dimensional coordinates of these two nodes as the starting and ending points for finding the spatial channel.

[0144] On the collision trajectory of aircraft A, find the last valid coordinate point before the starting coordinates of the collision zone. This valid coordinate point has not entered the collision zone and is the previous path node. Find the first valid coordinate point after the ending coordinates of the collision zone. This first valid coordinate point has left the collision zone and is the next path node. Determine the three-dimensional coordinates of these two nodes, which will serve as the starting and ending points for finding the bypass space passage, respectively.

[0145] Step S1456: Based on the starting point coordinates and the ending point coordinates, within the spatial range outside the prohibited passage area set, plan multiple potential connection routes. Each potential connection route consists of multiple consecutive coordinate nodes, forming a potential spatial passage.

[0146] Within the spatial range outside the prohibited areas, multiple potential connecting routes are planned using path planning algorithms (such as the A* algorithm), with the starting and ending coordinates as the two ends. Each route connects the starting and ending points by setting multiple intermediate coordinate nodes, and these consecutive coordinate nodes form a potential spatial passage.

[0147] Step S1457: For each potential spatial channel, extract the three-dimensional coordinates of all its coordinate nodes, calculate the distance between adjacent coordinate nodes, determine the extension direction of the channel, and then analyze the spatial width, height variation and path length of the channel. The spatial width is the maximum horizontal distance of the channel cross-section, the height variation is the height difference between the highest and lowest coordinate points in the channel, and the path length is the sum of the distances between all adjacent coordinate nodes.

[0148] For a potential spatial passage, extract the 3D coordinates of all its nodes. Calculate the straight-line distance between any two adjacent nodes, and determine the passage's extension direction (from the starting point to the ending point) based on the node arrangement. Analyze the passage's spatial width by calculating the maximum horizontal distance (e.g., the maximum distance in the east-west and north-south directions) within each of the passage's multiple cross-sections (perpendicular to the extension direction), and take the minimum value as the passage's spatial width. Calculate the maximum and minimum heights of all nodes within the passage; the difference between these two values ​​represents the height variation. Sum the distances between all adjacent nodes to obtain the path length.

[0149] Step S1458: Obtain the wingspan parameters and minimum safe flight altitude parameters of the corresponding low-altitude aircraft, calculate the preset multiple of the wingspan parameters, compare the minimum width of the potential space passage with the preset multiple of the wingspan parameters, and compare the minimum altitude coordinates within the potential space passage with the minimum safe flight altitude parameters. The preset multiple is set according to flight safety standards.

[0150] Obtain the wingspan parameters (maximum distance between the ends of the left and right wings) and minimum safe flight altitude parameters (minimum permissible flight altitude above the ground or obstacles) of aircraft A. Set a preset multiple (e.g., twice) for the wingspan parameters according to flight safety standards, and calculate the specific value of this preset multiple. Compare the minimum width of the potential space passage with this value, and simultaneously compare the minimum altitude coordinates of all coordinate nodes within the potential space passage with the minimum safe flight altitude parameters.

[0151] Step S1459: If the minimum width of the potential space passage is greater than or equal to a preset multiple of the wingspan parameter, and the lowest altitude coordinate within the passage is greater than or equal to the minimum safe flight altitude parameter, then it is preliminarily determined that the potential space passage meets the flight space requirements for low-altitude aircraft.

[0152] If the minimum width of a potential space passage is greater than or equal to a preset multiple of the wingspan parameter, it indicates that the passage has sufficient lateral space for aircraft A to turn and maneuver without colliding with obstacles on either side. Simultaneously, if the lowest altitude coordinate within the passage is greater than or equal to the minimum safe flight altitude parameter, it indicates sufficient vertical safety distance. Meeting these two conditions preliminarily determines that the potential space passage meets the flight space requirements.

[0153] Step S14510: Further extract wind speed, wind direction, and airflow disturbance data within the potential space passage from the meteorological dynamic change model, calculate the actual flight speed of each coordinate node within the potential space passage, and if the actual flight speed is between the maximum flight speed and the minimum safe flight speed of the low-altitude aircraft, and the degree of airflow disturbance is within the tolerance range of the wind resistance parameters of the low-altitude aircraft, then mark the potential space passage as a candidate space area that can be bypassed, record the starting coordinates, ending coordinates, and environmental feature information of the candidate space area, where the starting coordinates are the starting coordinates, the ending coordinates are the ending coordinates, and the environmental feature information includes average wind speed, main wind direction, and the proportion of unobstructed areas.

[0154] Wind speed, wind direction, and airflow disturbance data within the conflict zone time range are extracted from the meteorological dynamic change model. The actual flight speed of each coordinate node within the channel is calculated according to steps S1243 to S1244, and it is checked whether it is between the maximum and minimum safe flight speed of aircraft A. Simultaneously, it is determined whether the degree of airflow disturbance is within the tolerance range of aircraft A's wind resistance parameters (e.g., the airflow disturbance amplitude is less than the airflow disturbance threshold). If all conditions are met, the potential space channel is marked as a traversable alternative space area, and its starting coordinates (coordinates of the previous path node), ending coordinates (coordinates of the next path node), and environmental characteristic information (such as the average wind speed, main wind direction, and the proportion of unobstructed areas in the total area of ​​the channel) are recorded.

[0155] Step S14511: Repeat the above steps to filter out all candidate spatial areas that meet the conditions and form a list of candidate spatial areas that can be bypassed.

[0156] All planned potential spatial passages are analyzed and judged in steps S1457 to S14510, and all candidate spatial areas that meet the conditions are selected. Their information is then compiled into a list of candidate spatial areas that can be bypassed.

[0157] Step S146: Within the preset search range, exclude obstacle areas in the obstacle sub-model and severe weather areas in the meteorological dynamic change model, find alternative space areas that can be bypassed, record the boundary coordinates of the alternative space areas, and within the alternative space areas, re-plan the flight trajectory segment based on the mission start coordinates, mission end coordinates, and flight performance parameters of the target low-altitude aircraft, and determine the start coordinates, intermediate coordinate nodes, and end coordinates of the new trajectory segment.

[0158] Within the preset search range, the set of prohibited areas integrated in step S1454 is excluded, and a suitable alternative spatial area (such as the area with the shortest path length and the best environmental features) is selected from the list of alternative spatial areas that can be bypassed. The boundary coordinates (vertex coordinates of the 3D polygon) of this alternative spatial area are recorded. Within this area, the starting coordinates of the path node preceding the conflict area are taken as the starting coordinates of the new trajectory segment, and the ending coordinates of the path node following the conflict area are taken as the ending coordinates. Combining the mission start coordinates (express sorting center), mission end coordinates (customer delivery address), and flight performance parameters (maximum flight speed, endurance, etc.) of aircraft A, the flight trajectory segment is replanned using a path planning algorithm. Multiple intermediate coordinate nodes are set on the new trajectory segment to ensure that the trajectory is smooth and can avoid small obstacles in the area, and the starting coordinates, intermediate coordinate nodes, and ending coordinates of the new trajectory segment are determined.

[0159] Step S147: Extract the coordinate sequence of the new trajectory segment and the corresponding estimated passage time, compare it with the coordinate sequence and time axis of all other preset flight trajectories, calculate the spatial distance between the new trajectory segment and all other preset flight trajectories in each time slice. If all spatial distances are greater than the preset safe distance threshold, and the estimated passage time of the new trajectory segment is within the mission execution time window of the low-altitude aircraft, and the energy consumption corresponding to the new trajectory segment does not exceed the endurance parameter of the low-altitude aircraft, then the replanned flight trajectory segment is determined to be an effective adjusted trajectory segment.

[0160] Extract the coordinate sequence of the new trajectory segment (arranged in the order of starting coordinates, intermediate coordinate nodes, and ending coordinates). Based on the flight performance parameters of aircraft A and the meteorological data of the candidate space area, calculate the estimated time for passing through each coordinate node of the new trajectory segment, thus obtaining the estimated passage time of the new trajectory segment (total time and time for each node). Compare the coordinate sequence and time axis of the new trajectory segment with the coordinate sequences and time axes of the preset flight trajectories of all other low-altitude aircraft such as aircraft B and C, and calculate the spatial distance between the new trajectory segment and other trajectories in each time slice according to the method in step S133. If all spatial distances are greater than the preset safe distance threshold, the estimated passage time of the new trajectory segment is within the mission execution time window of aircraft A, and the energy consumption corresponding to the new trajectory segment calculated according to the method in step S1247 does not exceed the endurance parameter of aircraft A, then the new trajectory segment is determined to be a valid adjustment trajectory segment.

[0161] Step S148: The effectively adjusted trajectory segment is spliced ​​with other trajectory segments in the original conflict trajectory except for the conflict area. The coordinate sequence and estimated flight time of the spliced ​​complete trajectory are extracted. It is confirmed that the coordinates at the splicing point are continuous and the curvature change meets the flight control requirements, thus forming the corrected complete flight trajectory.

[0162] The adjusted trajectory segment will be spliced ​​with the original conflict trajectory segment before the conflict area (from the mission start point to the previous path node) and the trajectory segment after the conflict area (from the next path node to the mission end point). During splicing, ensure that the starting coordinates of the new trajectory segment are completely consistent with the ending coordinates of the trajectory segment before the conflict area (the previous path node), and that the ending coordinates of the new trajectory segment are completely consistent with the starting coordinates of the trajectory segment after the conflict area (the next path node), to guarantee coordinate continuity. Calculate the curvature change value of the complete spliced ​​trajectory to confirm that it meets the flight control requirements of Aircraft A. Extract the coordinate sequence and estimated flight time (the sum of the time of the non-conflict segment of the original trajectory and the estimated passage time of the new trajectory segment) of the complete spliced ​​trajectory to form the corrected complete flight trajectory.

[0163] Step S149: Based on the corrected complete flight trajectory, extract the low-altitude aircraft identifier, the starting coordinates of the trajectory segment to be adjusted, the coordinate sequence of the adjusted trajectory segment, and the estimated flight time after adjustment. The starting coordinates of the trajectory segment to be adjusted are the starting coordinates of the conflict area in the original conflict trajectory, the coordinate sequence of the adjusted trajectory segment is the coordinate sequence of the effective adjusted trajectory segment, and the estimated flight time after adjustment is the estimated flight time of the corrected complete flight trajectory. Generate a path adjustment command.

[0164] Extract the aircraft's identifier (such as aircraft number), the starting coordinates of the trajectory segment to be adjusted (the starting coordinates of the conflict area in the original conflict trajectory), the adjusted trajectory segment coordinate sequence (the coordinate sequence of the effective adjusted trajectory segment), and the adjusted estimated flight time (the estimated flight time of the corrected complete flight trajectory) from the corrected complete flight trajectory. Organize the above information according to a preset format to generate a path adjustment instruction.

[0165] Step S1410: Send the generated path adjustment command to the corresponding low-altitude aircraft control module, and replace the original conflict trajectory in the initial cooperative flight path set with the corrected complete flight trajectory to complete the update of the initial cooperative flight path set.

[0166] The generated path adjustment command is sent to the control module of aircraft A via a wireless communication network. After receiving the command, the control module prepares to execute the path adjustment. At the same time, in the initial set of cooperative flight paths, the original conflicting trajectory is replaced with the corrected complete flight trajectory of aircraft A, thus completing the update of the initial set of cooperative flight paths.

[0167] Step S1411: Perform cooperative conflict verification on the updated initial cooperative flight path set again. If conflicts still exist, repeat the above path adjustment steps until the updated initial cooperative flight path set has no conflict areas after conflict verification.

[0168] The updated initial cooperative flight path set is then subjected to another cooperative conflict verification process following step S130. If conflict areas still exist after verification, the path adjustment process from S141 to S1410 is repeated to redetermine the target low-altitude aircraft (which may still be Aircraft A or other aircraft involved in new conflicts) and replan the trajectory segments until the updated initial cooperative flight path set has no conflict areas after conflict verification. At this point, this initial cooperative flight path set is the final cooperative flight path set, which can be used to guide the cooperative flight of multiple low-altitude aircraft.

[0169] Based on the same inventive concept, please refer to Figure 2 This paper shows a schematic block diagram of a cooperative flight path planning system 100 for low-altitude aircraft, provided in an embodiment of this application, for executing the above-described cooperative flight path planning method for low-altitude aircraft. The cooperative flight path planning system 100 for low-altitude aircraft may include a communication unit 110, a machine-readable storage medium 120, and a processor 130.

[0170] In this embodiment, both the machine-readable storage medium 120 and the processor 130 are located within the cooperative flight path planning system 100 for low-altitude aircraft and are separately configured. However, it should be understood that the machine-readable storage medium 120 may also be independent of the cooperative flight path planning system 100 for low-altitude aircraft and may be accessed by the processor 130 via a bus interface. Alternatively, the machine-readable storage medium 120 may be integrated into the processor 130 and may communicate with external systems via the communication unit 110.

[0171] The processor 130 is the control center of the cooperative flight path planning system 100 for low-altitude aircraft. It connects to various parts of the system via various interfaces and lines. By running or executing software programs and / or modules stored in the machine-readable storage medium 120, and by calling data stored in the machine-readable storage medium 120, it performs various functions and processes data of the cooperative flight path planning system 100, thereby providing overall monitoring of the system. Optionally, the processor 130 may include one or more processing cores; for example, the processor 130 may integrate an application processor and a modem processor, wherein the application processor mainly handles the operating system, user interface, and applications, and the modem processor mainly handles wireless communication. It is understood that the modem processor may also not be integrated into the processor. The machine-readable storage medium 120 is used to store machine-executable instructions for executing the scheme of this application, and the processor 130 is used to execute the machine-executable instructions stored in the machine-readable storage medium 120 to implement the cooperative flight path planning method for low-altitude aircraft provided in the aforementioned method embodiments.

[0172] It should be noted that, in order to simplify the description of the present invention and thus help to understand one or more embodiments of the invention, multiple features may sometimes be grouped into one embodiment, drawing or description thereof in the foregoing description of the embodiments of the present invention.

Claims

1. A cooperative flight path planning method applied to low-altitude aerial vehicles, characterized by, The method comprises: constructing a three-dimensional dynamic flight environment model, which contains obstacle distribution information in a low-altitude area, real-time weather information, and task demand information of multiple low-altitude aircrafts; based on the three-dimensional dynamic flight environment model, combining flight performance parameters of each low-altitude aircraft, generating multiple sets of initial coordinated flight path sets, each path in the initial coordinated flight path set corresponding to a preset flight trajectory of a low-altitude aircraft; performing coordinated conflict checking processing on the initial coordinated flight path set, detecting overlapping areas of preset flight trajectories of different low-altitude aircrafts in time and space dimensions, and obtaining a coordinated conflict checking result; according to the coordinated conflict checking result, combining task priority sorting of multiple low-altitude aircrafts, generating path adjustment instructions, which are used to correct the preset flight trajectories with conflicts, so as to realize coordinated flight of multiple low-altitude aircrafts.

2. The cooperative flight path planning method for low altitude aerial vehicles according to claim 1, wherein, The method comprises: obtaining environmental basic data of a low-altitude area, which includes terrain data, fixed obstacle data, real-time weather monitoring data, and task parameter data of multiple low-altitude aircrafts in the low-altitude area; performing three-dimensional modeling processing on the terrain data to generate a terrain three-dimensional model, and marking out altitude change areas and terrain undulation feature areas in the terrain three-dimensional model; performing classification processing on the fixed obstacle data, adding corresponding obstacle three-dimensional models in the terrain three-dimensional model according to the types and height parameters of the obstacles, and forming an obstacle sub-model containing obstacle distribution information; performing time series analysis processing on the real-time weather monitoring data, extracting wind speed change information, wind direction change information, and air flow disturbance information in the weather data, constructing a weather dynamic change model as a carrier of real-time weather information; performing analysis processing on the task parameter data of the multiple low-altitude aircrafts, extracting task starting point coordinates, task ending point coordinates, task execution time windows, and task target requirements of each low-altitude aircraft, generating a task demand list as a carrier of task demand information; extracting spatial coordinate references in the obstacle sub-model, timestamp references in the weather dynamic change model, and task coordinate and time information in the task demand list; comparing the spatial coordinate references of the obstacle sub-model with the task coordinates of the task demand list, calculating a coordinate deviation value, if the coordinate deviation value exceeds a preset coordinate deviation threshold, adjusting the task coordinates of the task demand list to be consistent with the spatial coordinate references of the obstacle sub-model; comparing the timestamp references of the weather dynamic change model with the task execution time windows of the task demand list, calculating a time deviation value, if the time deviation value exceeds a preset time deviation threshold, adjusting the timestamp of the weather dynamic change model to be consistent with the time reference of the task demand list; comparing the timestamp reference of the meteorological dynamic change model with the task execution time window of the task demand list, calculating a time deviation value, and adjusting the timestamp of the meteorological dynamic change model to be consistent with the task demand list time reference if the time deviation value exceeds a preset time deviation threshold; after completing the coordinate and time adjustment, verifying the data correlation of the obstacle sub-model, the meteorological dynamic change model and the task demand list again, confirming that the deviations of each part of data in the spatial coordinate and time dimension are within a preset threshold range, and then performing data fusion processing on the three to generate a complete three-dimensional dynamic flight environment model; every preset time interval, reacquire the environment basic data, repeat the above coordinate and time verification and adjustment steps, and update the obstacle distribution information, real-time meteorological information and task demand information in the three-dimensional dynamic flight environment model. 3.The cooperative flight path planning method for low-altitude aerial vehicles of claim 1, wherein, based on the three-dimensional dynamic flight environment model, combining the flight performance parameters of each low-altitude aircraft, a plurality of initial cooperative flight path sets are generated, including: obtaining the flight performance parameters of each low-altitude aircraft, the flight performance parameters including maximum flight speed, maximum climb height, endurance capability parameters and wind resistance capability parameters; extracting the task starting point coordinates, task ending point coordinates and task execution time window corresponding to each low-altitude aircraft from the three-dimensional dynamic flight environment model; according to the task starting point coordinates and the task ending point coordinates, combining the terrain three-dimensional model and the obstacle sub-model in the three-dimensional dynamic flight environment model, a plurality of candidate paths without terrain and obstacle collision risk are preliminarily planned; for each candidate path, combining the flight performance parameters and the meteorological dynamic change model in the three-dimensional dynamic flight environment model, analyzing the influence of wind speed and direction on the flight speed and energy consumption of low-altitude aircraft on the candidate path, calculating the expected flight time and expected energy consumption parameters of each candidate path; according to the task execution time window, filtering out the candidate paths with expected flight time within the task execution time window to form an effective candidate path set; performing smoothing processing on each path in the effective candidate path set to eliminate sharp turning nodes in the path, calculating the curvature change value after smoothing the path, and confirming that the curvature change value meets the flight control requirements of low-altitude aircraft to obtain the smoothed candidate path; randomly selecting a path from the smoothed candidate paths of each low-altitude aircraft to form a path combination, and extracting the spatial coordinate sequence of the preset flight trajectory of all low-altitude aircraft in the path combination; calculating the minimum straight line distance between any two preset flight trajectories in the path combination in the spatial coordinate sequence, and if the minimum straight line distance is greater than a preset preliminary planning safety distance, the path combination is taken as an initial cooperative flight path set; If the minimum straight-line distance is less than or equal to the preset preliminary planning safety distance, a new path combination is selected, the above steps of spatial distance calculation and judgment are repeated, and multiple groups of initial cooperative flight path sets meeting the requirement of no obvious spatial overlap are screened out as the multiple groups of initial cooperative flight path sets, each of which contains preset flight trajectories of a corresponding number of low-altitude aircrafts.

4. The cooperative flight path planning method for low altitude aerial vehicles according to claim 2, wherein, The fixed obstacle data is classified and processed, corresponding obstacle three-dimensional models are added in the terrain three-dimensional model according to the types and height parameters of the obstacles, and an obstacle sub-model containing obstacle distribution information is formed, including: Information extraction is performed on each obstacle entry in the fixed obstacle data to obtain position coordinates, bottom area parameters, height parameters and obstacle type identifiers of the obstacles; According to the obstacle type identifiers, the obstacles are classified into building obstacles, power facility obstacles, communication tower obstacles and natural obstacle classes, and an obstacle classification list is established; For different types of obstacles, corresponding three-dimensional model templates are selected, the building obstacles use a cuboid combination model template, the power facility obstacles use a cylinder and cone combination model template, the communication tower obstacles use an elongated cylinder superposition model template, and the natural obstacle class uses an irregular polygon stretching model template; According to the position coordinates of the obstacles, corresponding projection coordinates of the position coordinates in the terrain three-dimensional model are calculated, and the selected three-dimensional model template is placed at the projection coordinate position of the terrain three-dimensional model; According to the bottom area parameters of the obstacles, the length and width dimensions required by the bottom of the three-dimensional model template are calculated, and the length and width of the three-dimensional model template are adjusted so that the bottom coverage range of the three-dimensional model is consistent with the actual bottom area of the obstacle; According to the height parameters of the obstacles, the height stretching amount required by the three-dimensional model template is calculated, and the height of the three-dimensional model template is stretched so that the height of the three-dimensional model is consistent with the actual height parameter of the obstacle; After completing the three-dimensional model construction of a single obstacle, the spatial distance between the three-dimensional model and the surrounding constructed obstacle three-dimensional models is measured, and it is confirmed that the spatial distance is greater than a preset model construction interval threshold, and then the three-dimensional model is added with an obstacle type label and a height attribute label. The above steps are repeated to complete the three-dimensional model construction of all fixed obstacles, and all obstacle three-dimensional models are integrated with the terrain three-dimensional model to extract the obstacle position, height and type information in the integrated model to form an obstacle sub-model containing obstacle distribution information.

5. The cooperative flight path planning method for low altitude aerial vehicles according to claim 3, wherein, For each candidate path, the influence of wind speed and direction on the flight speed and energy consumption of the low-altitude aircraft on the candidate path is analyzed in combination with the flight performance parameters and the meteorological dynamic change model in the three-dimensional dynamic flight environment model, the expected flight time and expected energy consumption parameters of each candidate path are calculated, including: The candidate path is divided into multiple path segments according to a preset distance interval, each path segment corresponds to a sub-region, the starting coordinates and ending coordinates of each sub-region are recorded, and the distance of each sub-region is calculated. extracting wind speed data and wind direction data corresponding to each sub-region from the meteorological dynamic change model, determining the size of the wind speed and the angle of the wind direction in each sub-region, and calculating the angle between the wind direction and the extension direction of the candidate path in the sub-region; calculating the component of the wind speed in the flight direction according to the maximum flight speed and the wind resistance parameter in the flight performance parameter of the low-altitude aircraft, combined with the wind speed and the wind direction angle of the sub-region; when the wind direction angle is less than 90 degrees, the actual flight speed is the sum of the maximum flight speed and the component of the wind speed in the flight direction; when the wind direction angle is greater than 90 degrees, the actual flight speed is the difference between the maximum flight speed and the component of the wind speed in the flight direction; calculating the difference between the actual flight speed and the preset minimum safe flight speed, and adjusting the actual flight speed to the minimum safe flight speed if the actual flight speed is lower than the minimum safe flight speed; calculating the time required for the low-altitude aircraft to pass through each sub-region according to the distance and the corresponding actual flight speed of each sub-region, adding the passing times of all sub-regions to obtain the estimated flight time of the candidate path; calculating the energy consumption of the low-altitude aircraft in each sub-region based on the endurance parameter of the low-altitude aircraft, combined with the actual flight speed, wind speed and wind resistance parameter of each sub-region, through a predefined energy consumption calculation model with consistent dimensions, which ensures that the energy consumption obtained after operation of the input parameters has a clear energy dimension; adding the energy consumptions of all sub-regions to obtain the estimated energy consumption parameter of the candidate path; comparing the calculated estimated energy consumption parameter with the maximum endurance energy consumption of the low-altitude aircraft, and marking the candidate path as an invalid path if the estimated energy consumption parameter exceeds the maximum endurance energy consumption; comparing the estimated flight time with the preset maximum tolerable time range, and also marking the candidate path as an invalid path if the estimated flight time exceeds the maximum tolerable time range.

6. The cooperative flight path planning method for low altitude aerial vehicles according to claim 1, wherein, The collaborative conflict checking process is performed on the initial collaborative flight path set to detect overlapping regions of the preset flight trajectories of different low-altitude aircrafts in the time dimension and the space dimension, and obtain a collaborative conflict checking result, including: adding a time axis mark to each preset flight trajectory in each initial collaborative flight path set, with the time axis mark starting from the take-off time of the low-altitude aircraft and ending at the estimated arrival time of the task terminal, and dividing the time axis into multiple time slices according to the preset time interval, and recording the start time and end time of each time slice; extracting a set of spatial coordinate points corresponding to each preset flight trajectory in each time slice, which contains multiple position coordinates of the low-altitude aircraft on the preset flight trajectory in the time slice, and recording the three-dimensional parameters of each position coordinate; calculating the spatial distance of the spatial coordinate point sets of different preset flight trajectories in the same time slice to calculate the straight-line distance between any two spatial coordinate points on different preset flight trajectories; The calculated straight line distance is compared with a preset safety distance threshold, and if there are two spatial coordinate points with a straight line distance less than the safety distance threshold, the starting time, ending time and position coordinates of the two spatial coordinate points of the time slice are recorded, it is determined that the preset flight trajectories corresponding to the two spatial coordinate points have a spatial overlap risk in the time slice, and the time slice and the corresponding spatial coordinate point position are marked as a conflict candidate region; After the conflict detection processing of all time slices, the number of conflict candidate regions in each initial cooperative flight path set is counted, and the time slice range and spatial coordinate range corresponding to each conflict candidate region are recorded, wherein the time slice range includes the starting time and the ending time, and the spatial coordinate range includes the three-dimensional parameter range of the position coordinates; The conflict candidate regions are further analyzed, the time slice range and spatial coordinate range of adjacent conflict candidate regions are extracted, and it is determined whether the ending time of a previous conflict candidate region is continuous with the starting time of a subsequent conflict candidate region and whether the spatial coordinate range of the previous conflict candidate region overlaps with the spatial coordinate range of the subsequent conflict candidate region; If the time is continuous and the spatial range overlaps, the corresponding conflict candidate regions are merged into a continuous conflict region, and the total starting time, total ending time and total spatial coordinate range of the continuous conflict region are recorded; According to the information of the conflict candidate regions and the continuous conflict regions in each initial cooperative flight path set, wherein the conflict candidate regions are unmerged conflict candidate regions, the initial cooperative flight path set identification without conflict, the initial cooperative flight path set identification with conflict, the time information and the spatial information of the conflict region are sorted, wherein the time information includes the starting time and the ending time, the spatial information includes the position coordinate range, and a cooperative conflict checking result is generated.

7. The cooperative flight path planning method for low altitude aerial vehicles according to claim 6, wherein, The spatial distance calculation of the spatial coordinate point sets of different preset flight trajectories in the same time slice includes: Two different preset flight trajectories are selected from the initial cooperative flight path set in the same time slice, and are denoted as a first preset flight trajectory and a second preset flight trajectory; A spatial coordinate point set of the first preset flight trajectory in the time slice is extracted and denoted as a first coordinate point set, and a spatial coordinate point set of the second preset flight trajectory in the time slice is extracted and denoted as a second coordinate point set; A spatial coordinate point is selected from the first coordinate point set and denoted as a first coordinate point, and the three-dimensional spatial coordinates of the first coordinate point include a first horizontal direction coordinate, a first vertical horizontal direction coordinate and a first height direction coordinate; A spatial coordinate point is selected from the second coordinate point set and denoted as a second coordinate point, and the three-dimensional spatial coordinates of the second coordinate point include a second horizontal direction coordinate, a second vertical horizontal direction coordinate and a second height direction coordinate; The straight line distance between the first coordinate point and the second coordinate point is calculated, and the calculated straight line distance and the three-dimensional spatial coordinate parameters of the first coordinate point and the three-dimensional spatial coordinate parameters of the second coordinate point are recorded; The straight line distance between the first coordinate point and the second coordinate point is calculated, and the calculated straight line distance and the three-dimensional spatial coordinate parameters of the first coordinate point and the three-dimensional spatial coordinate parameters of the second coordinate point are recorded; selecting a next uncalculated spatial coordinate point from the first coordinate point set, repeating the above straight-line distance calculation step until all spatial coordinate points in the first coordinate point set complete distance calculation with all spatial coordinate points in the second coordinate point set; selecting other uncombined two different preset flight trajectories from the initial cooperative flight path set as a new first preset flight trajectory and a second preset flight trajectory, repeating the above distance calculation step until all different preset flight trajectories in the same time slice complete straight-line distance calculation.

8. The cooperative flight path planning method for low altitude aerial vehicles according to claim 1, wherein, The path adjustment instruction is generated according to the cooperative conflict checking result and in combination with a task priority ranking of the multiple low-altitude flying vehicles, and includes: filtering, from the cooperative conflict checking result, an initial cooperative flight path set in which conflicts exist, extracting conflict region information in each initial cooperative flight path set in which conflicts exist, the conflict region information including a time range and a space range, and determining a preset flight trajectory corresponding to the conflict region, denoted as a conflict trajectory; obtaining a task priority ranking table of the multiple low-altitude flying vehicles, the task priority ranking table being determined according to an emergency degree of a task, importance of a task target, and a task execution period limit, each low-altitude flying vehicle corresponding to a priority level, and recording a determination basis of each priority level; extracting a priority level and a determination basis of a low-altitude flying vehicle corresponding to the conflict trajectory, comparing the priority levels corresponding to different conflict trajectories, and recording a comparison result; extracting priority levels of low-altitude flying vehicles corresponding to conflict trajectories, comparing the priority levels based on the task priority ranking table, and determining a target low-altitude flying vehicle whose flight path needs to be adjusted from the low-altitude flying vehicles in which conflicts exist according to a comparison result; for the conflict trajectory corresponding to the target low-altitude flying vehicle, extracting a time range and a space range of a conflict region, and in combination with an obstacle sub-model in the three-dimensional dynamic flight environment model and a meteorological dynamic change model, defining a preset search range around the conflict region, wherein the time range includes a start time and an end time, and the space range includes a position coordinate range, wherein the obstacle sub-model provides positions and heights of surrounding obstacles, and the meteorological dynamic change model provides surrounding wind speeds and directions; excluding, in the preset search range, an obstacle region in the obstacle sub-model and a severe weather region in the meteorological dynamic change model, finding an alternative space region that can be bypassed, recording boundary coordinates of the alternative space region, and in the alternative space region, re-planning a flight trajectory segment according to a task start point coordinate, a task end point coordinate, and flight performance parameters of the target low-altitude flying vehicle, and determining start coordinates, intermediate coordinate nodes, and end coordinates of a new trajectory segment; extract the coordinate sequence and the corresponding estimated passing time of the new trajectory segment, compare the coordinate sequence and the time axis of the new trajectory segment with the coordinate sequence and the time axis of all the preset flight trajectories, calculate the spatial distance between the new trajectory segment and other preset flight trajectories in each time slice, if all the spatial distances are greater than the preset safety distance threshold, and the estimated passing time of the new trajectory segment is within the task execution time window of the low-altitude aircraft, and the energy consumption corresponding to the new trajectory segment does not exceed the endurance capability parameter of the low-altitude aircraft, the re-planned flight trajectory segment is determined as an effective adjustment trajectory segment; splicing the effective adjustment trajectory segment and other trajectory segments in the original conflict trajectory except the conflict region, extracting the coordinate sequence and the estimated flight time of the complete trajectory after splicing, confirming that the coordinates at the splicing position are continuous and the curvature change meets the flight control requirements, and forming a corrected complete flight trajectory; extracting the low-altitude aircraft identifier, the starting coordinates of the trajectory segment to be adjusted, the coordinate sequence of the adjusted trajectory segment, and the adjusted estimated flight time according to the corrected complete flight trajectory, wherein the starting coordinates of the trajectory segment to be adjusted are the starting coordinates of the conflict region in the original conflict trajectory, the coordinate sequence of the adjusted trajectory segment is the coordinate sequence of the effective adjustment trajectory segment, and the adjusted estimated flight time is the estimated flight time of the corrected complete flight trajectory, and generating a path adjustment instruction; sending the generated path adjustment instruction to the corresponding low-altitude aircraft control module, and replacing the original conflict trajectory in the initial cooperative flight path set with the corrected complete flight trajectory, to complete the update of the initial cooperative flight path set; performing cooperative conflict checking on the updated initial cooperative flight path set again, if there is still a conflict, repeating the above path adjustment steps until there is no conflict region after the conflict checking of the updated initial cooperative flight path set.

9. A cooperative flight path planning system for low altitude aerial vehicles, characterized by, comprise: a processor; a machine-readable storage medium for storing machine-executable instructions of the processor; wherein the processor is configured to execute the application method for cooperative flight path planning of low-altitude aircraft in any one of claims 1-8 by executing the machine-executable instructions.

10. A computer program product, characterised in that, The computer program product comprises machine-executable instructions stored in a computer-readable storage medium, and a processor of a computer device reads the machine-executable instructions from the computer-readable storage medium, and the processor executes the machine-executable instructions, so that the computer device executes the application method for cooperative flight path planning of low-altitude aircraft in any one of claims 1-8.

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