Low-altitude airspace aircraft flight path planning system

Abstract

The invention relates to the technical field of path planning, in particular to a low-altitude airspace aircraft flight path planning system which comprises a task analysis module, an airspace modeling module, a path generation module, a feasibility verification module and a path output module. According to the method, sight distance flight rule grade judgment is introduced in airspace boundary extraction to eliminate airspace sections which do not meet the minimum sight distance reference requirement, a connection diagram is constructed, combined calculation of the wind shear angle and the building projection density is executed, and through quantitative analysis of the ratio of the path section height to the wind pressure change gradient, the wind shear angle and the building projection density are calculated. The method comprises the following steps: performing intensity risk labeling on a path in an unstable airflow area to realize path continuity and stability discrimination, constructing a continuous instruction point group based on a stable fragment sequence in a path combination stage, and setting speed and steering adjustment thresholds, so as to enhance the adaptability and execution robustness of a path execution sequence to flight control; and the air route feasibility and the risk avoidance capability in a complex low-altitude environment are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of route planning, in particular to a low-altitude airspace vehicle flight route planning system. BACKGROUND

[0002] The technical field of route planning mainly involves the theory and method of generating an optimal or feasible moving path for a moving target under certain constraints. This field includes but is not limited to path generation algorithms, path smoothing and optimization, obstacle avoidance, dynamic environment adaptation, energy consumption constraints, time window scheduling, etc. Route planning is widely used in automatic driving, robot navigation, traffic management, unmanned aerial vehicle scheduling, ship track planning, etc. The focus is on how the target moves in space from the starting point to the ending point to achieve the optimal efficiency, cost, safety, etc.

[0003] Among them, the low-altitude airspace vehicle flight route planning system is a system for generating a flight path for a vehicle flying in low-altitude airspace. Its purpose is to generate a flight path that meets the safety, efficiency and compliance of the route according to the flight mission requirements, vehicle performance parameters, airspace restrictions, terrain information, weather conditions and other factors. This system can improve the flight autonomy and operation coordination capability of the vehicle in complex low-altitude environment, and is widely used in urban air traffic, logistics distribution, patrol monitoring and other application scenarios.

[0004] The traditional planning system only relies on task requirements and static information such as conventional airspace, weather, terrain, etc. to generate paths, which is difficult to identify the airspace exclusion characteristics implied by the labeled expression in the scheduling task, resulting in that part of the task cannot be quantitatively processed for specific no-entry areas or line-of-sight maintenance requirements, and there is a lack of differentiated judgment mechanism for the level of airspace exclusion in the path selection process. When extracting airspace segments, the low-altitude obstacle density and wind shear angle change are not jointly constrained at the path level, which may cause the path planning result to pass through a local strong disturbance area. If it encounters a high-density building environment or variable airflow conditions, it will cause the vehicle path to be unstable, the flight control command to be frequently adjusted, and the path execution consistency and flight safety level to be reduced. SUMMARY

[0005] The purpose of the present application is to solve the problems existing in the prior art and to provide a low-altitude airspace vehicle flight route planning system.

[0006] In order to achieve the above purpose, the present application adopts the following technical scheme: a low-altitude airspace vehicle flight route planning system, the system comprises: The task analysis module obtains low-altitude vehicle scheduling task data, judges whether the label item is a restriction item with airspace exclusion characteristics, compares the numbers of the airspace segments in the airspace division level table, and generates airspace exclusion flag information; The airspace modeling module determines whether the airspace segment corresponding to the exclusion mark is a forced exclusion mark based on the airspace exclusion mark information, sets the forced exclusion as an invalid area, extracts airspace segments with complete boundary closure and a visual flight rule level greater than a basic VFR level reference value from the remaining airspace segments, and generates a low-altitude flight path candidate airspace set; The path generation module collects low-altitude layer height, wind shear angle distribution, and building projection density corresponding to each path segment based on the low-altitude flight path candidate airspace set, performs risk distribution screening on the ratio of low-altitude obstacle projection number to airspace segment width, and generates low-altitude flight risk guidance initial path information; The feasibility verification module calls the low-altitude flight risk guidance initial path information, determines whether each path height is in a wind pressure variation severe section, eliminates high-risk labeled path segments, combines continuous stable segments in the remaining path segments, and generates a low-altitude flight feasible path sequence.

[0007] The present application improves that the airspace exclusion mark information includes airspace identification code, task limitation mapping table, exclusion level index, airspace adaptation mark and conflict judgment value, the low-altitude flight path candidate airspace set includes passable airspace segment number, boundary coordinate group, visual rule label, minimum flight height group and regional traffic priority, the low-altitude flight risk guidance initial path information includes path node number graph, wind shear angle offset value layer, path obstacle density score set, direction difference angle reference set and path segment risk weight set, and the low-altitude flight feasible path sequence is specifically node height set, path segment wind pressure sensitivity level, path continuity mapping sequence and wind pressure elimination path identification set.

[0008] The present application improves that the task analysis module includes: The task information extraction submodule obtains low-altitude aircraft scheduling task data, and the task data includes task type, flight start and end point pair, visual distance maintenance time and forbidden area level, extracts field items marked as path planning strongly related attributes in the task label, numbers and classifies the field values in the extracted fields, and establishes a task label index list based on the numbering and classification results to generate a task label index sequence; The restriction label screening submodule screens label items marked as path forced restriction attributes based on the task label index sequence, calls attribute levels and exclusion level standard values corresponding to the label items, determines whether the attribute level is greater than the exclusion level standard value, and performs screening processing on the label items that meet the conditions to generate an airspace exclusion restriction number set; The airspace sign generation submodule calls airspace segment airspace number and layout level value in the airspace layout level table according to the airspace exclusion limit number set, compares the airspace segment level value and the label level value corresponding to each number in the exclusion limit number set, sets the airspace segment with a greater relationship as an airspace exclusion sign segment, establishes a corresponding structure table of the airspace segment number and the exclusion sign, and generates airspace exclusion sign information.

[0009] The airspace modeling module comprises: The boundary data extraction submodule extracts the numerical parameter item in the effective data structure based on the airspace exclusion sign information, calls the spatial boundary coordinates, the minimum flight height limit and the VFR level of the airspace segment corresponding to the number in the low-altitude airspace level, and generates an airspace segment structure parameter value set; The exclusion sign judgment submodule obtains the airspace segment identification level and the exclusion level threshold value based on the airspace segment structure parameter value set and the number information and corresponding exclusion sign value of each airspace segment, performs difference calculation on the airspace segment identification level and the exclusion level threshold value, compares the difference result with the set feasible interval range, obtains the exclusion relative intensity value of the identifiable segment, marks the airspace segment with an exclusion relative intensity value greater than the exclusion judgment reference value as a forced exclusion segment, and generates an exclusion level screening result; The feasible region screening submodule calls the exclusion level screening result, extracts the boundary coordinate point group of the corresponding airspace segment according to the airspace number of the non-forced exclusion segment, performs closedness test, compares whether the VFR level is greater than the basic VFR level reference value, and if the closedness is established and the level is greater than the reference value, the path planning candidate region list is included, and a low-altitude flight path candidate airspace set is generated.

[0010] The path generation module comprises: The connection graph construction submodule generates a region topology edge connection relationship according to the boundary vertex coordinate point set of each airspace segment based on the low-altitude flight path candidate airspace set, establishes a node adjacency sequence and a corresponding boundary direction relationship matrix, and generates airspace segment connection graph structure information; The node mapping identification submodule collects the task start point coordinates and end point coordinates in the aircraft task scheduling table according to the airspace segment connection graph structure information, performs distance comparison on the coordinate points and the nodes in the graph structure, judges the node number corresponding to the shortest distance, and records it as a mapping start point and a mapping end point, and generates a task node mapping index pair. The path risk screening submodule calls the task node mapping index pair, traverses each path segment node sequence in the connection graph structure, collects the wind shear angle change value, path orientation angle, obstacle projection number and airspace segment effective width in each unit segment of the path segment, calculates the obstacle distribution ratio and jointly discriminates the wind shear disturbance value, calculates the comprehensive risk value of each path segment, constructs the continuous path graph segment according to the path segment set with the comprehensive risk value less than the path risk screening threshold, and generates the low-altitude flight risk guidance initial path information.

[0011] The feasibility verification module comprises: The high-altitude wind pressure judgment submodule calls the low-altitude flight risk guidance initial path information, cross-judges the height value of each path segment node and the wind pressure gradient change interval range according to the node height value of the path segment and the wind pressure gradient value of the corresponding path segment, screens out the data in the boundary fuzzy section and identifies the remaining section belonging to the stable or severe category, and generates the wind pressure section judgment classification information; The risk intensity calculation submodule calculates the risk intensity value of the severe path segment based on the wind pressure section judgment classification information according to the path segment marked as the wind pressure disturbance severe category, collects the wind pressure change amplitude, node average height, path slope change amount and aircraft ceiling height of each path segment, performs wind pressure and height relative risk coefficient calculation, and obtains the risk intensity value of the severe path segment, marks the path segment with the risk intensity value greater than the wind pressure risk reference value as the high-risk category, and generates the high-risk path marking result; The stable path combination submodule calls the high-risk path marking result, performs continuity judgment on adjacent path segments according to the path number order according to the path segment not marked as high-risk, excludes the broken section and combines it into a continuous path segment group, establishes a structure mapping relationship and regenerates a task corresponding path index set, and obtains a low-altitude flight feasible path sequence.

[0012] The system further comprises: The path output module obtains the aircraft heading control data structure template based on the low-altitude flight feasible path sequence according to the node coordinates of each path segment, constructs a continuous instruction control point group, arranges the head and tail nodes of the path segment in the flight instruction sequence order, assembles a path execution set, and generates a low-altitude air route control structure sequence. The low-altitude air route control structure sequence comprises a path segment control instruction set, a heading control point number, a speed control configuration table, a flight turning angle sequence and a path segment execution time axis.

[0013] The path output module comprises: The heading template generation submodule generates control template structure index information based on the low-altitude flight feasible path sequence, sorts node coordinates according to each path segment, calls a heading control template structure in an aircraft configuration library, performs template structure index positioning based on a path direction vector and a node density interval matching table, acquires a corresponding template matching relationship table, and generates control template structure index information. The node instruction construction submodule extracts the first and last node coordinates of each path segment as a path segment execution starting point and ending point based on the control template structure index information, performs an included angle judgment on a path segment direction vector and a template reference heading, matches a path segment speed constant and a heading adjustment interval boundary value in combination with a speed parameter setting range of an aircraft task number, establishes a binding relationship between a path segment number and an instruction field, and generates path node execution instruction information. The instruction set assembly submodule constructs a continuous path instruction set list according to a path segment order based on the path node execution instruction information, performs parameter nesting on a direction code, a speed value and a steering control angle threshold of each path segment, implements path segment navigation control data field integration, and generates a low-altitude air route control structure sequence.

[0014] Compared with the prior art, the advantages and positive effects of the present application are as follows: In the present application, by structuring and stripping the visual distance keeping time and the forbidden level in the flight task, precision filtering can be performed on the label information with airspace exclusion characteristics, the airspace level table is mapped by numbering, the flag information that can determine the forced exclusion relationship is generated, the visual flight rule level judgment is introduced in the airspace boundary extraction to exclude the airspace segments that do not meet the minimum visual distance reference requirement, the connection graph is constructed and the wind shear angle and building projection density joint calculation are performed, the initial path information with wind shear difference guidance is generated, the path in the unstable airflow area is marked with intensity risk through the quantitative analysis of the ratio of path segment height to wind pressure gradient, the path continuity and stability discrimination is realized, the continuous instruction point group is constructed based on the stable segment sequence in the path combination stage and the speed and steering adjustment threshold is set, the adaptability and execution robustness of the path execution sequence to flight control are enhanced, and the air route feasibility and risk avoidance ability in complex low-altitude environment are improved. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 The system flowchart of the present application is shown in the figure; Figure 2 The flowchart of the task analysis module of the present application is shown in the figure; Figure 3 The flowchart of the airspace modeling module of the present application is shown in the figure; Figure 4 The flowchart of the path generation module of the present application is shown in the figure; Figure 5 A flow chart of the feasibility verification module of the present application; Figure 6 A flow chart of the path output module of the present application. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and do not limit the present application.

[0017] In the description of the present application, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, in the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0018] Referring to Figure 1 The present application provides a technical scheme: a low-altitude airspace vehicle flight route planning system, the system comprising a task analysis module, an airspace modeling module, a path generation module, a feasibility verification module and a path output module; The task analysis module obtains low-altitude vehicle scheduling task data, the task data including task type, flight start and end point pair, line-of-sight keeping time length and exclusion area level, performing priority peeling on the three contents in the task label, judging whether the label item is a restriction item with airspace exclusion characteristics, and generating an exclusion flag based on the restriction item number and level, comparing the airspace segments in the airspace grading table, and generating airspace exclusion flag information; The airspace modeling module, based on the airspace exclusion flag information, calls the spatial boundary coordinates, minimum flight height limit, line-of-sight flight rule level of each airspace segment at the low-altitude airspace level, judges whether the exclusion flag corresponding to the airspace segment is a forced exclusion mark, if it is a forced exclusion, it is set as an invalid area, if it is a non-forced exclusion, it is set as a lower priority area, extracts the airspace segments in the remaining airspace segments that have complete boundary closure and line-of-sight flight rule level greater than the basic VFR level reference value, and generates a low-altitude flight path candidate airspace set; The path generation module generates a connection graph of airspace segments based on the set of low-altitude flight path candidate airspace, according to the boundary vertex set of each airspace segment, obtains the start and end coordinate points of the aircraft task, identifies the mapping nodes of the start and end points in the airspace connection graph, collects the low-altitude layer height, wind shear angle distribution and building projection density corresponding to each path segment, performs angle difference judgment on the wind shear angle change value and path orientation difference value of the path segment, performs risk distribution screening on the ratio of the number of low-altitude obstacles to the width of the airspace segment, and performs weighted offset value operation on the nodes in the screened path segment according to the wind shear difference and obstacle risk score, to generate initial path information for low-altitude flight risk guidance; The feasibility verification module calls the initial path information for low-altitude flight risk guidance, judges whether the height of each path segment is in a section with a sharp change in wind pressure according to the height information of the path segment node, the wind pressure gradient and the aircraft climb height, calculates the ratio between the wind pressure change amplitude and the climb height, labels the risk intensity of the path segment, removes the high-risk labeled path segment, and combines the continuous stable segments in the remaining path segments to generate a sequence of feasible low-altitude flight paths. The path output module generates a sequence of low-altitude flight paths based on the sequence of feasible low-altitude flight paths, obtains an aircraft heading control data structure template according to the node coordinates of each path segment, constructs a continuous instruction control point group, arranges the first and last nodes of each path segment in the order of flight instruction sequence, sets the flight speed constant and the steering angle adjustment threshold of each path segment, assembles a path execution set, and generates a sequence of low-altitude route control structures. The minimum flight height limit refers to the minimum safe flight height of an aircraft in a specific airspace or terrain condition according to aviation regulations, which is usually set according to flight regulations and topographic maps; the visual flight rule level refers to the restriction on whether an aircraft can fly by visual rules in airspace classification; the wind shear angle is the angle difference formed by the change of wind speed and direction encountered by the aircraft in a short distance, which is a measure of wind shear effect; the building projection density represents the number of obstacles higher than the minimum flight altitude in a specific grid unit, which is used to evaluate the complexity of flight obstacles in airspace; the wind pressure gradient represents the change rate of wind pressure per unit distance, which is a key meteorological parameter affecting flight path disturbance, and is usually obtained from high-altitude meteorological data or LIDAR echo; the steering angle adjustment threshold is the maximum directional change rate that an aircraft can tolerate or effectively control in continuous heading adjustment, which is used to limit the control accuracy of turning segments in the path. The airspace exclusion flag information includes airspace identification code, task restriction mapping table, exclusion level index, airspace adaptation mark and conflict judgment value, the low-altitude flight path candidate airspace set includes passable airspace segment number, boundary coordinate group, line-of-sight rule label, minimum flight height group and regional traffic priority, the low-altitude flight risk guidance initial path information includes path node number graph, wind shear angle offset value layer, path obstacle density score set, direction difference angle reference set and path segment risk weight set, the low-altitude flight feasible path sequence is specifically node height set, path segment wind pressure sensitivity level, path continuity mapping sequence and wind pressure excluded path identification set, and the low-altitude air route control structure sequence includes path segment control instruction set, heading control point number, speed control configuration table, flight turning angle sequence and path segment execution time axis.

[0019] Please refer to Figure 2 The task analysis module includes: The task information extraction submodule obtains low-altitude aircraft scheduling task data, the task data including task type, flight start and end point pair, line-of-sight keeping time length and exclusion area level, extracting the field items marked as path planning strongly related attributes in the task label, numbering and classifying the field values in the extracted fields, and establishing a task label index list based on the numbering and classification results to generate a task label index sequence; The task information extraction submodule processes based on the task type, start and end point coordinates, line-of-sight keeping duration, and exclusion area level of each vehicle in the scheduling task. First, the original data fields of each task record are extracted and structured and numbered, for example, the task type "monitoring task" is set as T1, "logistics distribution" is set as T2, and "geographical mapping" is set as T3. The start and end point pairs are recorded in the form of latitude and longitude coordinates and are uniformly converted into two-dimensional index pairs. In this embodiment, the start and end points of UAV001 are (116.30, 39.90)-(116.40, 39.95), numbered N1-N5. The line-of-sight keeping duration is divided into three intervals: [0, 90], (90, 150], and (150, 180], with interval level values V1=1, V2=2, and V3=3, respectively. This setting is based on the line-of-sight keeping ability of the vehicle ground control system, for example, most small unmanned aerial vehicles have a line-of-sight keeping ability of about 90 seconds within the control distance. Therefore, 90 seconds is set as the first division line, and 150 seconds is set as the maximum continuous flight time. UAV002 corresponds to 90 seconds and is divided into V1, UAV001 is divided into V2 with 120 seconds, and the exclusion area level is based on the national airspace division standard level (1-5 levels). The path planning label system set by the task database is used, and levels 3 and above are considered as restriction attribute labels. The task field items are numbered and labeled accordingly, such as exclusion level 4 marked as F4. The numbered fields are set with a number mapping function, and the initial task label tuple is composed of the number combination. The extraction result of each task is entered into the label sequence in the form of a tuple, for example, the label combination of UAV003 is T3, N3-N6, V3, and F4. Finally, the label tuples in the whole task table are merged and de-duplicated to generate the task label index sequence. Table 1: Task field extraction example table Aircraft number Task type Origin coordinates Destination coordinates Loiter time / s No-entry area level UAV001 Monitoring task (116.30,39.90) (116.40,39.95) 120 3 UAV002 Logistics delivery (116.35,39.88) (116.45,39.92) 90 2 UAV003 Geographical mapping (116.28,39.92) (116.38,39.97) 150 4 As shown in Table 1, the extraction and classification of field values in a typical vehicle task scheduling table are shown, which can provide input basis for task label index structure construction.

[0020] The restriction label screening submodule is based on the task label index sequence. The label items with path forced restriction attributes are marked as the basic label. The attribute level and exclusion level standard value corresponding to the label item are called to determine whether the attribute level is greater than the exclusion level standard value. The label items that meet the conditions are screened and the airspace exclusion restriction number set is generated. The limit label screening submodule carries out judgment processing according to the label items marked as path forced limit attributes in the task label index sequence. First, the exclusion level standard value reference table is called, in which the label with the entry level greater than or equal to 3 is regarded as having the mandatory attribute. In the present embodiment, the exclusion level standard value R_base is set to 3, which is a reference to the airspace classification specified by the national civil airspace management rules for the area with a flight height below 150 meters. The relationship between the entry level of the task and R_base is judged. If the attribute level value is greater than R_base, the limit item is regarded as being excluded. For example, the level value corresponding to F4 is 4, and the current exclusion level standard value is 3. Therefore, F4 is retained because it meets the condition. In addition, the auxiliary limit reference value of the visual range maintenance time is set to the minimum visual constraint level V_min=2. According to the definition of the control continuity time of most models, which is derived from the average maintenance time greater than 105 seconds in Table 1, the level is divided into V2. Therefore, V_min=2 is set as the screening threshold. The label with a maintenance level lower than V_min in the task is regarded as having no stable control guarantee condition. For example, the V1 corresponding task field is marked as an exclusion task. Finally, the number set example {F3, F4, V1} is formed to construct the path segment screening basis and generate the airspace exclusion limit number set.

[0021] The airspace flag generation submodule calls the airspace segment number and setup level value in the airspace setup level table according to the airspace exclusion limit number set, compares the airspace segment level value with the label level value corresponding to each number in the exclusion limit number set, and sets the airspace segment with a greater relationship as the airspace exclusion flag segment. The corresponding structure table of the airspace segment number and the exclusion flag is established, and the airspace exclusion flag information is generated. The airspace flag generation submodule performs level comparison operations on all airspace segments in the airspace setup level table according to the airspace exclusion limit number set. In the specific implementation, first, the number and its setup level value of each airspace segment are obtained. For example, the level value of the airspace segment with the number S12 is 4, and the level of the number S7 is 2. The corresponding value of F4 in the exclusion number set is 4. When the airspace segment level value and the exclusion level value are compared, the greater than or equal to judgment reference is set to “whether the airspace level value ≥ the label level value”. If the relationship is established, the airspace is marked as exclusion. In addition, for the combined limit judgment, such as the combination of F4 and V1, the track accessibility index of the airspace segment needs to be judged for auxiliary constraint. If the average visual coverage time of the segment is less than V_min=2, the combination is regarded as the exclusion condition. The exclusion label group weight discrimination weight W is set to 1.0. When both labels meet the condition, the exclusion weight product is W^2=1.0, and the segment is directly judged to be excluded. If only one item meets the condition, W=1 is recorded, and the segment is still included in the comparison sequence. Finally, the structured list composed of the number-exclusion Boolean pair is generated, such as {S12:True, S7:False, S19:True}. According to this, the airspace identification structure table is established, and the airspace exclusion flag information is formed.

[0022] Please see Figure 3 The spatial domain modeling module includes: The boundary data extraction submodule, based on the airspace exclusion flag information, calls three parameters—spatial boundary coordinates, minimum flight altitude limit, and visual line of sight flight rule level—for each airspace segment corresponding to the number under the low-altitude airspace level to extract numerical parameter items from the effective data structure and generate a set of airspace segment structure parameter values. The boundary data extraction submodule obtains the corresponding number of each airspace segment from the airspace exclusion flag information, and in this embodiment, selects ten airspace segments numbered S01 to S10 for sample extraction processing. First, it retrieves the boundary coordinate set of each numbered airspace segment through the low-altitude airspace hierarchy database interface. Each set of boundary points consists of no less than 4 two-dimensional coordinate points, forming a closed polygon outline. Then, it reads the minimum flight altitude value set for that segment. For example, the minimum flight altitude of S03 is 160m, and the maximum allowable flight altitude for the mission is set to 400m, so the normalized value is... Then, read the visual line-of-sight flight rule level value set for the airspace segment. In this implementation, the rule level is taken as level 1 to 6. If the S03 level is 3, then the normalized value is... Next, the perimeter length of the closed polygon formed by the boundary point set is determined. If the boundary length is 2400m, and the global maximum spatial boundary length is 6000m, then after normalization... All normalized values ​​and their original numbers are stored in a structured matrix table and bound to a Boolean value for exclusion flags to form an input value set.

[0023] Table 2. Examples of Normalized Values ​​of Airspace Segment Structure Parameters As shown in Table 2, the structural parameters of each spatial segment are normalized to form a unified dimension input, which facilitates the subsequent calculation and processing of the rejection value.

[0024] The exclusion flag determination submodule, based on the spatial segment structure parameter value set, obtains the spatial segment identification level and exclusion level threshold according to the numbering information and corresponding exclusion flag value of each spatial segment. It then calculates the difference between the spatial segment identification level and the exclusion level threshold, and compares the difference result with a set feasible range, using the following formula: ; The relative repulsion strength value of the discriminable segment is obtained by calculation. The spatial segment with a relative repulsion strength value greater than the repulsion judgment benchmark value is marked as a forced repulsion segment, and the repulsion level screening result is generated. in, This represents the relative intensity of repulsion in the airspace segment; a larger value indicates a stronger repulsion level. This refers to the identification level value for the airspace segment. For the rejection level threshold, The normalized value for the minimum flight altitude limit is obtained by dividing the original altitude by the maximum permissible flight altitude for the mission. The normalized value for the visual line of sight (VLS) flight rule level is obtained by comparing the original level with the maximum level range. This is the normalized value of the closed length of the airspace boundary, obtained by the ratio of the boundary length to the global maximum boundary length of the airspace. The wind shear disturbance coefficient is the product of the standard deviation of wind direction and the standard deviation of wind speed in this airspace segment, which measures the degree of wind disturbance fluctuation in this segment. The rejection flag determination submodule filters entries based on their numbers and Boolean flags within the spatial segment structure parameter value set. It then performs rejection strength value determination on entries marked True in numbers S01–S10 and sets a rejection level threshold. Airspace segment identification level value Retrieved from the structure library, for example, if S02 is set to 4, then... The normalized values ​​in Table 2 are used for calculation, and S02 corresponds to... , , Disturbance coefficient Standard deviation of wind direction and wind speed standard deviation For multiplication calculations, if the values ​​are 1.2 and 0.8 respectively, then... Substitute into the formula: ; The first term in the formula The first term represents the degree of difference between the airspace segment's identification level and the set exclusion level, used to measure the deviation of the airspace itself from the exclusion criteria in terms of classification standards; the larger the difference, the closer it is to the exclusion boundary. The second term is a joint measure of airspace environmental disturbance and flight complexity, where the square root term... The strength of the combined requirements for airspace in terms of both minimum flight altitude restrictions and visual line-of-sight flight rule levels is measured, and then expressed through the denominator. The normalized value of the closed boundary length of the airspace is converted. The longer the boundary, the more complex the airspace. The larger the denominator factor, the more diluted the overall perturbation weight is. Finally, it is multiplied by... This represents a nonlinear amplification of the severity of wind shear disturbances. The logarithmic function term grows faster when the disturbance is stronger, and its influence on the degree of repulsion is enhanced. The overall structure can be regarded as a superposition expression of the risks of airspace complexity and disturbance.

[0025] The specific calculations are as follows: ; The result This indicates that the repulsion strength of the airspace segment S02 has exceeded the set repulsion judgment benchmark value. This indicates that the airspace segment not only exhibits significant differences in exclusion level, but also suffers from a combined effect of structural complexity, flight altitude constraints, and disturbance amplitude, resulting in a higher overall exclusion risk. Therefore, S02 is marked as a mandatory exclusion segment and included in the mandatory exclusion number list as a component of the exclusion level screening results. This result will be used to exclude airspace areas that are inaccessible to aircraft when subsequently screening candidate path areas, serving as an airspace filtering function in path planning.

[0026] The feasible area screening submodule calls the rejection level screening results, extracts the boundary coordinate point group of the corresponding airspace segment based on the airspace number marked as non-mandatory rejection segment, and performs closure test. At the same time, it compares whether the visual line of sight flight rule level is greater than the basic VFR level benchmark value. If the closure is satisfied and the level is greater than the benchmark value, it is included in the path planning candidate area list and a set of low-altitude flight path candidate airspaces is generated. The feasible area screening submodule calls the non-mandatory exclusion segment numbers in the exclusion level screening results. For example, if the numbers S01 and S03 do not exceed the benchmark exclusion strength value, its boundary coordinate point set is extracted and closedness is judged. The node counterclockwise directed loop construction verification method is used to judge polygon closure. S01 and S03 both pass the closure test. Then, its visual line of sight (VFR) level is read and compared with the VFR level benchmark value. In this implementation, the VFR level benchmark value is set to 3, which is derived from the requirement in the Civil Aviation Airspace Use Specification of China that visual line of sight level of not less than 3 is required for Class G airspace to allow visual flight in Class A–G airspace. If the level of S01 is 2, it does not meet the requirement, while the level of S03 is 3, it does meet the requirement. Finally, only the airspace segments that simultaneously meet the closure and level benchmark are retained and included in the candidate path area list to generate a set of candidate airspaces for low-altitude flight paths.

[0027] Please see Figure 4 The path generation module includes: The connection graph construction submodule is based on the candidate airspace set of low-altitude flight paths. According to the set of boundary vertex coordinates of each airspace segment, it generates regional topological edge connection relationships for the coordinates according to spatial connection boundary rules, establishes node adjacency sequences and corresponding boundary direction relationship matrices, and generates airspace segment connection graph structure information. Obtain the set of boundary vertex coordinates for each airspace segment in the candidate airspace set for low-altitude flight paths. Sort the vertices corresponding to each airspace segment in a clockwise direction. After sorting, perform a pairwise judgment according to the spatial connection boundary rules. If the Euclidean distance between two vertices is less than the path construction baseline threshold... If a point is found to have a boundary connectivity relationship, a connecting edge structure is added between the point pairs. After obtaining all connecting edges, the global point set is traversed, and for each point, adjacent points with which it has a connection are numbered and their adjacency relationships are recorded as a sequence structure. At the same time, for each connecting edge, the direction angle of the edge is calculated based on the difference in vertex coordinates. The connection edges of each node are constructed, ultimately generating the spatial segment connection graph structure information, where boundary connection is determined by... The baseline threshold is based on the maximum allowable bend radius of the path for drones in low-altitude areas. The settings are as follows: if the Euclidean distance between the connection points exceeds... If the flight path is not precisely controlled during path construction, the error will be within [a certain range]. Within this range, there is a risk of track deviation, therefore edges are not constructed, and the directional angles between points are not considered. The direction value is obtained by performing an arctangent operation on the difference between coordinate vectors. For example, if the starting coordinates are... The destination is The direction angle is calculated as follows: The final obtained connection graph structure value is used as the topological basis for subsequent path graph segment construction; The node mapping identification submodule collects the starting and ending coordinates of the mission in the aircraft mission scheduling table based on the airspace segment connection graph structure information, performs distance comparison between the coordinate points and nodes in the graph structure, determines the node number corresponding to the shortest distance, and records it as the mapping starting point and mapping ending point, generating mission node mapping index pairs. Based on the airspace segment connection diagram structure information, collect the mission start-point and end-point coordinates and mission number from the aircraft mission scheduling table. The corresponding starting coordinates are The destination is Calculate the Euclidean distance between the starting point coordinates and the coordinates of all nodes in the graph structure, and select the shortest distance as the mapping starting point. For example, the minimum distance is [value missing]. At that time, its corresponding node number is ,but The starting point of the mapping is the node number; similarly, the ending point corresponds to the mapping node number. This ultimately forms task node mapping index pairs. The Euclidean distance is calculated using the standard formula: ; Starting point With candidate nodes For example, the distance is calculated as follows: ; Table 3 shows the Euclidean distances between some nodes and the starting point. The node with the smallest distance is the final index result. Table 3. Euclidean distances from the task start point to some nodes. See Table 3, nodes The task node mapping index pair that is closest to the starting point is... ; The path risk screening submodule calls the task node mapping index pairs, traverses the node sequence of each path segment in the connection graph structure, and collects the wind shear angle change value, path orientation angle, number of obstacle projections, and effective width of the airspace segment for each unit segment in the path segment. It calculates the obstacle distribution ratio and performs joint discrimination with the wind shear disturbance value, using the following formula: ; The comprehensive risk value of each path segment is obtained through calculation. Based on the set of path segments whose comprehensive risk value is less than the path risk screening threshold, a continuous path map segment is constructed to generate initial path information for low-altitude flight risk guidance. in, This represents the overall risk value of the path segment. Indicates the angle between the path segment direction and the wind shear direction. To normalize the wind shear angle variation value, To normalize the obstacle projection density, To normalize the width of the airspace segment, This is the wind shear response weighting constant. This represents the dispersion factor of the disturbance distribution in this segment, calculated as the ratio of the local disturbance standard deviation to the mean of the path segment; Call the start and end node numbers in the task node mapping index pair and In the connection graph structure, a depth-first strategy is used to traverse all path segments from the start point to the end point, and the wind shear angle variation value is collected for each unit segment within each path segment. Path orientation angle Number of obstacle projections With the effective width of the airspace segment Calculate the normalized value of the obstacle projection density. Width normalized to Path angle Normalization Wind shearing Normalization Dispersion distribution discrete factor This is the ratio of the standard deviation to the mean of the wind shear. It is expressed by the following formula: ; The formula logic is explained as follows: First item This indicates the weighting of the difference between the path and the wind shear direction in the risk. The larger the value, the greater the directional deviation. The larger the value, the more sensitive the wind shear effect. Second item This indicates the combined risk effect of wind shear disturbance and obstacle density; the greater both are, the higher the overall risk. denominator It is used to represent the weighted compression effect of risk in a narrow area. The larger the B is, the higher the passage margin and the lower the risk. Last item It characterizes the moderating effect of disturbance volatility on overall risk. The larger the value, the more unstable the disturbance. The larger the value; The parameters are set as follows: , , , , , ; Substitute the values ​​and calculate as follows: ; If the path risk screening threshold is If the overall risk value of the path segment is less than the threshold, it is determined to be a feasible path segment. This result indicates that the overall risk value of the path segment is within the feasible range and is suitable for the low-altitude path execution phase. The final low-altitude flight risk guidance initial path information is obtained by continuously splicing multiple such segments.

[0028] Please see Figure 5 The feasibility verification module includes: The high-altitude wind pressure judgment submodule calls the initial path information for low-altitude flight risk guidance. Based on the node height value of the path segment and the wind pressure gradient value of the corresponding path segment, it calls the service ceiling height defined in the aircraft platform technical specifications, cross-judges the height value of each path segment node and the range of wind pressure gradient change, filters out data in the boundary ambiguity segment and identifies the remaining segment to the stable or severe category, and generates wind pressure segment judgment classification information. Obtain the node altitude values ​​and corresponding wind pressure gradient values ​​for all path segments in the initial path information for low-altitude flight risk guidance. Retrieve the node altitude values ​​for each path segment from the original mission structure, and iterate through the node sequence for each path segment. Then, process the node altitude data according to the aircraft's service ceiling. Perform a scaling normalization operation, calling the parameters defined in the aircraft platform technical specifications. Determine node height The range of wind pressure gradient changes in the current path segment The intersection relationship, where the setting , If the wind pressure gradient corresponding to the node height is in and If the interval is between these intervals, it is considered a stable interval; otherwise, it is considered a violent interval. Exclusions are made if the interval is within the boundary ambiguity zone and the node density is insufficient. The boundary segments are identified, and the remaining segments are classified and labeled according to the gradient strength to obtain wind pressure segment classification information, which is used for subsequent calculations.

[0029] The risk intensity calculation submodule classifies wind pressure zones based on this information. For each path segment marked as experiencing severe wind pressure disturbance, it collects data on wind pressure variation, average node height, path gradient variation, and aircraft ceiling altitude. It then calculates the relative risk coefficient between wind pressure and altitude using the following formula: ; The risk intensity value of the severe path segment is obtained by calculation. The path segment with the risk intensity value greater than the wind pressure risk benchmark value is marked as high risk category, and the high risk path marking result is generated. in, This indicates the risk intensity value of the path segment. This is a normalized value for the wind pressure variation, calculated by dividing the wind pressure variation by the maximum wind pressure variation within the flight area. This is a normalized value for the average altitude of the path segment, calculated by dividing the average altitude by the aircraft's service ceiling. This is a normalized representation of the aircraft's service ceiling, fixed at 1 to avoid dimensionlessness. This is a normalized value for the change in path slope, defined as the ratio of the change in slope within the current path segment to the maximum global slope difference for the task. This is the normalized value of the standard deviation of node height within the path segment, calculated as the ratio of the standard deviation to the maximum height variation interval. The path segment disturbance dispersion coefficient is calculated as the ratio of the variance of the wind pressure disturbance sequence to the average wind pressure at the corresponding node. Based on the wind pressure zone classification information, identify the path segments marked as having severe wind pressure disturbance, and collect the wind pressure change amplitude for each path segment. Average node height Path slope change Service ceiling of aircraft The relative risk coefficient of wind pressure and altitude is calculated using the following formula: ; Formula calculation logic explanation: First item This indicates the relative impact of wind pressure disturbance intensity on the safety margin of aircraft flight altitude, where... The normalized value of wind pressure change is squared to increase its influence weight. The denominator represents the difference between the service ceiling and the current flight altitude, i.e., the flight margin. A constant of 1 is added to avoid the denominator being zero; the second term... The risk level is increased if there is a discrepancy between the standard deviations of slope and height fluctuations and a large wind pressure dispersion. As a disturbance stability suppression term, it avoids the effect of drastic amplification of dispersion. The final calculated... This reflects the risk intensity value of a route segment. If a route segment experiences significant wind disturbance, limited flight margin, and severe terrain undulation, the overall risk will rise rapidly, and the corresponding risk intensity value will increase accordingly. If the wind pressure risk is significantly greater than the benchmark value, it should be determined as an infeasible section, thus affecting the overall feasibility screening of the route.

[0030] The sample path segment parameters are set as follows: This means that the wind pressure change in this path segment is 85% of the maximum wind pressure change in the region, stemming from the fact that the wind pressure change in this path segment is... The maximum change value is set to ; This indicates that the average altitude is 90% of the aircraft's service ceiling, and the original altitude is... service ceiling Fixed setting This fixed value is taken from the performance index boundary parameters in the platform manual and does not participate in numerical fluctuations; The normalized slope variation result originates from the slope difference in this section. The global maximum slope difference for the task is set to The normalized value is calculated as follows: ; The ratio of the standard deviation of node height to the maximum node height difference, where the standard deviation of the node is... The maximum height range is Therefore, the normalized value is ; Wind disturbance variance Average wind pressure Therefore, the disturbance dispersion coefficient is .

[0031] The specific calculation is as follows: Substitute into the formula and perform the calculation: ; Based on the calculation results, the risk intensity value of this path segment can be obtained. To determine whether this value belongs to the high-risk category, a risk benchmark value needs to be set. .

[0032] Wind pressure risk benchmark Set as This value is set based on the 80th percentile calculated from the most severe wind pressure disturbance segment in the statistical area. The normalized value after removing outliers is used as the boundary standard, specifically referring to 30 samples from the most severe disturbance segments. The mean is 0.6, the standard deviation is 0.1, and the calculated 80% confidence limit is... .

[0033] This result indicates that: due to the risk intensity value of the path segment Greater than the set wind pressure risk benchmark value Therefore, this path segment is marked as a high-risk path segment and input into the high-risk path marking result set.

[0034] The stable path combination submodule calls the high-risk path marking results, performs continuity judgment on adjacent path segments according to the path number order based on the path segments that are not marked as high-risk, eliminates broken segments and combines them into a continuous path segment group, establishes structural mapping relationship and regenerates the path index set corresponding to the task to obtain the low-altitude flight feasible path sequence. The system retrieves path segments not marked as high-risk from the high-risk path labeling results, performs continuity checks on adjacent path segments in path number order, and indexes and labels breakpoints in the node sequence. A breakpoint threshold is set as the distance between consecutive nodes being greater than [a certain value]. If path segments meet the requirements of number continuity and the distance between nodes does not exceed the breakage threshold, they are classified into continuous segment combinations. All node and boundary information within a segment is integrated to construct a segment group topology table. After filtering out isolated segment groups, valid segment groups are sorted by task number, and a mapping table is established to regenerate the task path index set, ultimately generating a sequence of feasible low-altitude flight paths. The continuity judgment operation calls upon the aforementioned high-risk path marking results. The breakage judgment between segments is directly calculated based on the Euclidean distance between node coordinates. Segment groups that meet the segment structure stability requirements can be used as candidate flight segments. Path numbering example: If path segments B2, B3, and B4 meet the continuity condition, they are combined into segment group B234. An index is created for this group, and a numbering table is output for subsequent use by the path control structure generation module.

[0035] Please see Figure 6 The path output module includes: The heading template generation submodule is based on the sequence of feasible low-altitude flight paths. According to the coordinates of all nodes in each path segment, the node coordinates are numbered and sorted, and the heading control template structure in the aircraft configuration library is called. The template structure is located by indexing the path direction vector and the node density interval matching table, the corresponding template matching relationship table is obtained, and the control template structure index information is generated. To obtain the coordinates of all nodes in each path segment of the feasible low-altitude flight path sequence, first, all node coordinates in each path segment are numbered. For example, path segment S1 contains nodes A1, A2, and A3, whose three-dimensional coordinates are (10, 20, 100), (20, 30, 110), and (30, 35, 120) respectively, and are recorded as A1 to A3 in numerical order. Simultaneously, the density interval between nodes is calculated. In this example, the average spacing between nodes is 15m. Based on the path segment direction vector (20, 15, 20), the magnitude of the path direction vector is calculated to be approximately 32.4, corresponding to a heading angle of 45°. The heading control template structure defined in the aircraft configuration library is then retrieved from the table. The interval matching condition is 30° to 60°, and the node density matching interval is 12m to 18m. At this time, all the conditions of template number T01 are met. The template field attributes are read from the template structure, and a mapping index between the node number and the template field is established for the current path segment. Finally, the control template structure index information is generated. The upper and lower limits of the directional interval matching are used as the upper and lower limits of the "threshold" of the directional angle deviation matching. The basis for setting is that the aircraft has stable control capability when the heading offset error is within 15°. The upper and lower limits of the node density matching interval are used as the "baseline value" of the node density setting. This value is taken from the density range recommended in the path segment control requirements in the task type of urban complex airspace environment.

[0036] The node instruction construction submodule is based on the control template structure index information. According to the field attributes of the corresponding template structure, it extracts the coordinates of the first and last nodes of each path segment as the start and end points of the path segment execution. It judges the angle between the path segment direction vector and the template reference heading. Combined with the speed parameter setting range of the aircraft mission number, it matches the speed constant and heading adjustment interval boundary value of each path segment, establishes the binding relationship between the path segment number and the instruction field, and generates path node execution instruction information. Based on the template number determined in the control template structure index information, the first and last nodes of each path segment are selected as the start and end points of the path segment. Taking path segment S1 as an example, the coordinates of A1 are (10, 20, 100), the coordinates of A3 are (30, 35, 120), the direction vector is (20, 15, 20), and the reference heading vector in template T01 is set to (21, 15, 19). The three-dimensional angle formula is used: ; The included angle value is compared with the maximum deviation angle of 15° set in template T01. If it is less than the threshold, the matching condition is met. The "heading adjustment interval boundary value" is set to 15°, which is a fixed "threshold" defined by the system. Its source is the maximum lateral correction angle limit allowed by the flight control module. This value will fluctuate due to changes in flight control stability. The range is generally set to 12° to 18°. In this task, it is set to 15° because the mission speed constant is set to 12m / s. System simulation verification shows that the maximum tolerance angle for stable heading deviation at this speed is 15°. In addition, the flight speed range of mission number M001 is set to [10,15]m / s. The configured speed is read as 12m / s through the mission configuration file. Combining this speed value with the included angle result, the parameter binding result of path segment S1 is constructed: [direction vector (20,15,20), speed 12m / s, heading adjustment threshold 15°]. Finally, the path node execution command information is generated.

[0037] The instruction set assembly submodule executes instruction information based on path nodes. According to the path segment order, it constructs a continuous path instruction set list by node number, nests the direction code, speed value, and steering control angle threshold of each path segment as parameters, integrates the navigation control data fields of the path segments, and generates a low-altitude route control structure sequence. Based on the path segment order in the path node execution instruction information, the execution parameters of path segments S1, S2, and S3 are read sequentially. S1 has a direction vector of (20, 15, 20), a direction code of 101, a speed of 12 m / s, and a steering angle threshold of 15°. S2 has a direction vector of (18, 0, 10), a code of 100, a speed of 10 m / s, and a steering angle threshold of 10°. S3 has a direction vector of (28, 10, 8), a code of 110, a speed of 14 m / s, and a threshold of 18°. These fields are encapsulated to form a continuous path instruction set and embedded into the path segment control structure. S1: [101,12,15]; S2: [100,10,10]; S3: [110,14,18]; The "turning control angle threshold" for each path segment is the upper limit of adjustment determined by the heading adjustment sensitivity corresponding to the path density. The setting standard is as follows: when the average distance between nodes is less than 12m, the angle threshold is set to 10°; when the distance is greater than 20m, it is set to 20°, to ensure that the heading adjustment action is completed within the control sequence. Path segments S1, S2, and S3 fall within the medium-low-high density range, respectively, so their corresponding thresholds are set to 15°, 10°, and 18°, respectively. This setting is derived from the matching standard between the aircraft's heading control time window and the minimum turning radius. After integrating the control command set data and establishing a structure mapping table with the path segment numbers, the low-altitude flight path control structure sequence is finally generated.

[0038] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments that can be applied to other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A flight path planning system for low-altitude airspace aircraft, characterized in that, The system includes: The task parsing module obtains low-altitude aircraft scheduling task data, determines whether the tag item is a restriction item with airspace exclusion characteristics, compares the airspace segments in the airspace classification level table by number, and generates airspace exclusion flag information. Based on the airspace exclusion flag information, the airspace modeling module determines whether the airspace segment corresponding to the exclusion flag is a forced exclusion flag. If it is a forced exclusion, it is set as an invalid area. The module extracts the airspace segments with closed and complete boundaries and visual line of sight flight rule level greater than the basic VFR level benchmark value from the remaining airspace segments and generates a set of candidate airspaces for low-altitude flight paths. Based on the set of candidate airspaces for low-altitude flight paths, the path generation module collects the low-altitude layer height, wind shear angle distribution and building projection density for each path segment, performs risk distribution screening on the ratio of the number of low-altitude obstacle projections to the width of the airspace segment, and generates initial path information for low-altitude flight risk guidance. The feasibility verification module calls the initial path information for low-altitude flight risk guidance, determines whether the altitude of each path segment is in a region of drastic wind pressure changes, removes high-risk path segments, and combines the continuous stable segments in the remaining path segments to generate a sequence of feasible low-altitude flight paths.

2. The low-altitude airspace aircraft flight route planning system according to claim 1, characterized in that, The airspace exclusion information includes airspace identification code, mission restriction mapping table, exclusion level index, airspace adaptation mark and conflict judgment value. The candidate airspace set for low-altitude flight paths includes passable airspace segment number, boundary coordinate group, visibility rule label, minimum flight altitude group and area access priority. The initial path information for low-altitude flight risk guidance includes path node number map, wind shear angle offset value layer, path obstacle density score set, direction difference angle reference set and path segment risk weight set. The feasible low-altitude flight path sequence specifically includes node height set, path segment wind pressure sensitivity level, path continuity mapping sequence and wind pressure rejection path identifier set.

3. The low-altitude airspace vehicle flight route planning system according to claim 2, characterized in that, The task parsing module includes: The task information extraction submodule acquires low-altitude aircraft scheduling task data, including task type, flight start-end point pair, visual distance maintenance duration and restricted area level. It extracts fields marked as strongly related to path planning from the task tags, numbers and classifies the field values ​​in the extracted fields, and builds a task tag index list based on the numbering and classification results, generating a task tag index sequence. The restriction label filtering submodule, based on the task label index sequence, identifies the label items that are fundamentally marked as path mandatory restriction attributes, calls the attribute level and exclusion level standard value corresponding to the label item, determines whether the attribute level is greater than the exclusion level standard value, and performs filtering processing on the label items that meet the conditions to generate a set of spatial exclusion restriction numbers. The airspace flag generation submodule, based on the airspace exclusion restriction number set, calls the airspace number and classification level value of the airspace segment in the airspace classification level table, compares the airspace segment level value with the tag level value corresponding to each number in the exclusion restriction number set, and sets the airspace segment with the greater relationship as the airspace exclusion flag segment, establishes a correspondence structure table between airspace segment number and exclusion flag, and generates airspace exclusion flag information.

4. The low-altitude airspace aircraft flight route planning system according to claim 3, characterized in that, The spatial domain modeling module includes: Based on the airspace exclusion flag information, the boundary data extraction submodule calls three parameters—spatial boundary coordinates, minimum flight altitude limit, and visual line of sight flight rule level—for each airspace segment according to its corresponding number, and extracts the numerical parameter items from the effective data structure to generate a set of airspace segment structure parameter values. The exclusion flag judgment submodule, based on the set of spatial segment structure parameter values, obtains the spatial segment identification level and exclusion level threshold according to the numbering information of each spatial segment and the corresponding exclusion flag value, performs the difference calculation between the spatial segment identification level and the exclusion level threshold, compares the difference result with the set feasible range, calculates the relative exclusion strength value of the discriminable segment, marks the spatial segment with the relative exclusion strength value greater than the exclusion judgment benchmark value as a forced exclusion segment, and generates the exclusion level screening result. The feasible area screening submodule calls the exclusion level screening results, extracts the boundary coordinate point group of the corresponding airspace segment according to the airspace number marked as non-mandatory exclusion segment, and performs closure test. At the same time, it compares whether the visual line of sight flight rule level is greater than the basic VFR level benchmark value. If the closure is satisfied and the level is greater than the benchmark value, it is included in the path planning candidate area list, and a set of low-altitude flight path candidate airspaces is generated.

5. The low-altitude airspace vehicle flight route planning system according to claim 4, characterized in that, The path generation module includes: The connection graph construction submodule, based on the candidate airspace set of the low-altitude flight path, generates regional topological edge connection relationships for the coordinate points according to the spatial connection boundary rules of the boundary vertex coordinate point set of each airspace segment, establishes the node adjacency sequence and the corresponding boundary direction relationship matrix, and generates the airspace segment connection graph structure information. The node mapping identification submodule collects the starting coordinates and ending coordinates of the mission in the aircraft mission scheduling table based on the airspace segment connection graph structure information, performs distance comparison between the coordinate points and nodes in the graph structure, determines the node number corresponding to the shortest distance, and records it as the mapping starting point and mapping ending point, generating a task node mapping index pair. The path risk screening submodule calls the task node mapping index pair, traverses the node sequence of each path segment in the connection graph structure, collects the wind shear angle change value, path orientation angle, number of obstacle projections and effective width of the airspace segment for each unit segment in the path segment, calculates the obstacle distribution ratio and performs joint discrimination with the wind shear disturbance value, calculates the comprehensive risk value of each path segment, and constructs continuous path graph segments based on the set of path segments whose comprehensive risk value is less than the path risk screening threshold, generating initial path information for low-altitude flight risk guidance.

6. The low-altitude airspace vehicle flight route planning system according to claim 5, characterized in that, The feasibility verification module includes: The high-altitude wind pressure judgment submodule calls the initial path information for low-altitude flight risk guidance. Based on the node height value of the path segment and the wind pressure gradient value of the corresponding path segment, it calls the service ceiling height defined in the aircraft platform technical specifications, cross-judges the height value of each path segment node and the range of wind pressure gradient changes, filters out data in the boundary ambiguity segment and identifies the remaining segments to the stable or severe category, and generates wind pressure segment judgment classification information. The risk intensity calculation submodule determines the classification information based on the wind pressure section. According to the path segments marked as severe wind pressure disturbance, it collects the wind pressure change amplitude, average node height, path slope change, and aircraft ceiling altitude for each path segment. It performs the calculation of the relative risk coefficient between wind pressure and altitude, calculates the risk intensity value of the severe path segment, and marks the path segment with the risk intensity value greater than the wind pressure risk benchmark value as a high-risk category, generating a high-risk path marking result. The stable path combination submodule calls the high-risk path marking results, performs continuity judgment on adjacent path segments according to the path number order based on the path segments not marked as high-risk, eliminates broken segments and combines them into a continuous path segment group, establishes a structural mapping relationship and regenerates the path index set corresponding to the task, and obtains a sequence of feasible low-altitude flight paths.

7. The low-altitude airspace vehicle flight route planning system according to claim 6, characterized in that, The system also includes: Based on the feasible low-altitude flight path sequence, the path output module obtains the aircraft heading control data structure template according to the node coordinates of each path segment, constructs a continuous command control point group, arranges the first and last nodes of the path segment in the order of the flight command sequence, assembles them into a path execution set, and generates a low-altitude flight path control structure sequence. The low-altitude flight path control structure sequence includes a path segment control instruction set, a heading control point number, a speed control configuration table, a flight turning angle sequence, and a path segment execution time axis.

8. The low-altitude airspace vehicle flight path planning system according to claim 7, characterized in that, The path output module includes: The heading template generation submodule, based on the low-altitude flight feasible path sequence, numbers and sorts the node coordinates according to all node coordinates of each path segment, calls the heading control template structure in the aircraft configuration library, performs template structure index positioning according to the path direction vector and node density interval matching table, obtains the corresponding template matching relationship table, and generates control template structure index information. The node instruction construction submodule, based on the control template structure index information, extracts the coordinates of the first and last nodes of each path segment as the start and end points of the path segment execution according to the field attributes of the corresponding template structure, judges the angle between the path segment direction vector and the template reference heading, and matches the speed constant and heading adjustment interval boundary value of each path segment with the speed parameter setting range of the aircraft mission number, establishes the binding relationship between the path segment number and the instruction field, and generates path node execution instruction information. The instruction set assembly submodule executes instruction information based on the path nodes, constructs a continuous path instruction set list according to the path segment order and node number, nests the direction code, speed value, and steering control angle threshold of each path segment as parameters, integrates the navigation control data fields of the path segments, and generates a low-altitude route control structure sequence.

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