Flight path planning and evaluation method under severe weather conditions

Abstract

The application discloses a flight path planning and evaluation method under severe weather conditions, comprising the following steps: acquiring a weather distribution map and all planned flight paths, determining whether each planned flight path is affected by weather according to the weather distribution map, classifying the planned flight paths affected by weather as abnormal flight paths, and classifying the planned flight paths not affected by weather as normal flight paths; for each abnormal flight path, a plurality of preselected flight paths are planned by avoiding weather influence according to the A* algorithm combined with the weather distribution map, the comprehensive score of each preselected flight path is calculated according to the weather distribution map, the preselected flight path with the highest score is selected to replace the abnormal flight path, and the abnormal flight path after the replacement is classified as a normal flight path; step S2 is repeated until each planned flight path is not affected by weather, and the path planning is completed. The application solves the problem of single focus and low planning efficiency of the path planning method in the prior art by solving multiple flight paths by the A* algorithm and comprehensively evaluating the multiple flight paths, so that the path planning is optimized.

Description

Technical Field

[0001] This invention relates to the field of flight route management technology, and in particular to a method for planning and evaluating flight detour routes under adverse weather conditions. Background Technology

[0002] Severe weather is a major threat to air transport safety and a significant cause of flight delays. When certain airspace or routes are unusable due to severe weather, rerouting can effectively solve this problem by arranging flights to temporarily choose an unaffected route to bypass the hazardous weather area. Flight rerouting route planning is a key issue in rerouting strategies. Research on flight rerouting route planning by foreign scholars began as early as the 1990s, proposing several representative algorithms: grid-based route search, free-flight-based route search algorithms, and polygon-based route search algorithms. Chinese scholars began researching flight rerouting route planning in 2001. However, in existing research, free-flight-based rerouting route planning is currently not applicable in my country; route search algorithms based on existing waypoints often result in longer rerouting routes, increasing economic burden; elliptical-based hazard zone delineation only exists in ideal conditions and lacks persuasiveness; initial rerouting routes generated by geometric algorithms often cross hazard zones, requiring continuous corrections to generate a final rerouting route that meets the conditions, increasing computational load.

[0003] In addition, existing research focuses on path planning aimed at avoiding danger zones and minimizing the path length, which often deviates significantly from the original planned trajectory. Furthermore, in actual operation, other evaluation indicators such as conflict, efficiency, and regularity need to be considered. Existing research rarely involves a comprehensive evaluation of path planning results.

[0004] Therefore, a path planning method that can balance avoiding dangerous areas with comprehensive evaluation is needed. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a method for planning and evaluating flight detour routes under adverse weather conditions. It uses the A* algorithm to solve for multiple detour routes and comprehensively evaluates these routes to select the optimal route. This solves the problems of existing route planning methods having a single focus and low planning efficiency.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A method for flight detour planning and evaluation under severe weather conditions includes the following steps:

[0008] S1. Obtain the weather distribution map and all planned flight tracks. Based on the weather distribution map, determine whether each planned flight track is affected by the weather. Planned flight tracks affected by the weather are classified as abnormal flight tracks, and planned flight tracks not affected by the weather are classified as normal flight tracks.

[0009] S2. For each abnormal flight path, according to the A* algorithm and the weather distribution map, several pre-selected flight paths are planned to avoid the influence of weather. The comprehensive score of each pre-selected flight path is calculated according to the weather distribution map. The pre-selected flight path with the highest score is selected to replace the abnormal flight path. The replaced abnormal flight path is classified as a normal flight path.

[0010] S3. Repeat step S2 until each planned route is unaffected by weather, thus completing the route planning.

[0011] Furthermore, the color value of each pixel in the meteorological distribution map corresponds to the meteorological conditions at the corresponding location. The meteorological distribution map is divided into several grids of the same size. When the color value of any pixel in the grid exceeds a preset threshold, the location corresponding to that pixel is considered to have dangerous weather, and the grid is designated as an impassable grid. All impassable grids are combined to form an impassable area.

[0012] Furthermore, in step S1, the specific implementation of determining whether each planned flight path is affected by the weather based on the meteorological distribution map is as follows: for each planned flight path, if any part of the planned flight path does not cross an impassable area, then the planned flight path is a normal flight path; if any part of the planned flight path crosses an impassable area, then the planned flight path is an abnormal flight path.

[0013] Further, in step S2, the specific implementation of planning several pre-selected flight paths to avoid weather impacts based on the A* algorithm and meteorological distribution map is as follows: the abnormal flight path includes N track points, which divide the abnormal flight path into N-1 segments. All segments of the abnormal flight path that pass through impassable areas are marked as dangerous segments. Dangerous segments that continuously pass through impassable areas are merged into the same dangerous segment. For each dangerous segment k, path planning is performed, which includes:

[0014] Select the (k-1)th waypoint as the planning start point A and the (k+1)th waypoint as the planning end point S. Perform path planning from the planning start point A to the planning end point S according to the A* algorithm.

[0015] Furthermore, the specific implementation of path planning from the planning starting point A to the planning ending point S using the A* algorithm is as follows: the objective function of the A* algorithm is:

[0016] And satisfy ,

[0017] in, Point , The distance between them, where m represents the number of waypoints and L represents the track. Indicates an area that is impassable;

[0018] The optimization cost function of the A* algorithm is:

[0019] f(n) = g(n) + h(n)

[0020] Where f(n) represents the estimated cost function from the planning starting point A to the current node n, and then from the current node n to the planning endpoint S, g(n) is the actual cost function from the flight starting point A to the current node n, and h(n) is the heuristic function, which is the estimated cost function from the current node n to the planning endpoint S.

[0021] The actual cost function g(n) is:

[0022] g(n) =

[0023] in, This represents the coordinates of the i-th point from the starting point A to the current point n. When i=0, Starting point A of the plan, Point , The distance between them.

[0024] Furthermore, it also includes: for each dangerous segment of each abnormal trajectory, setting different planning start points and / or planning end points, using the A* algorithm for path planning, and obtaining several different pre-selected trajectories.

[0025] Furthermore, it also includes smoothing the pre-selected trajectory, the smoothing specifically including:

[0026] For each segment of the pre-selected route, if the straightened segment will not pass through an impassable area, then the segment will be straightened.

[0027] Furthermore, in step S2, the calculation of the comprehensive score for each pre-selected flight path based on the meteorological distribution map is specifically implemented by the following method: the comprehensive score includes safety indicators, efficiency indicators, regularity indicators, and conflict indicators.

[0028] Furthermore, each pixel in the meteorological distribution map is further divided into safe and risky weather based on its color value. When risky weather exists within a grid but no dangerous weather exists, that grid is designated as a risky grid. The formula for calculating the safety index s is as follows:

[0029]

[0030] Where L is the set of grids traversed by the trajectory. The set of all grids in the impassable area. The set of all risk grids;

[0031] The efficiency index d is calculated using the following formula:

[0032]

[0033] in, This indicates the length of the pre-selected route. This indicates the length of the original planned route corresponding to the preselected route;

[0034] For each point on the pre-selected track, when the point on the pre-selected track ,point The distances to the originally planned flight path were all less than the preset parameters. At that time, the recording point ,point Distance between The formula for calculating the regularity index r is:

[0035]

[0036] in, This indicates the length of the original planned track corresponding to the preselected track;

[0037] The formula for calculating the conflict index c is as follows:

[0038]

[0039] in, Indicates the pre-selected track. This represents the j-th planned route out of all planned routes. express The number of intersections between them.

[0040] Furthermore, the formula for calculating the comprehensive score is as follows:

[0041]

[0042] In the formula:

[0043]

[0044] Where s represents the safety index, d represents the efficiency index, c represents the conflict index, ad represents the weight value of the efficiency index, ar represents the weight value of the regularity index, and cr represents the weight value of the conflict index.

[0045] Through the above technical solution, the present invention has the following beneficial effects:

[0046] By using the A* algorithm to set different planning start and end points for route planning, and by referring to multiple indicators to evaluate different routes, the unaffected planned flight segments can be fully utilized. A comprehensive evaluation index system for detour routes is proposed, which can obtain the optimal route from multiple detour routes. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the overall process of a method for planning and evaluating flight detour routes under severe weather conditions according to the present invention. Detailed Implementation

[0048] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0049] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0050] Example 1

[0051] See Figure 1 A method for flight detour planning and evaluation under severe weather conditions includes the following steps:

[0052] S1. Obtain the weather distribution map and all planned flight tracks. Based on the weather distribution map, determine whether each planned flight track is affected by the weather. Planned flight tracks affected by the weather are classified as abnormal flight tracks, and planned flight tracks not affected by the weather are classified as normal flight tracks.

[0053] S2. For each abnormal flight path, according to the A* algorithm and the weather distribution map, several pre-selected flight paths are planned to avoid the influence of weather. The comprehensive score of each pre-selected flight path is calculated according to the weather distribution map. The pre-selected flight path with the highest score is selected to replace the abnormal flight path. The replaced abnormal flight path is classified as a normal flight path.

[0054] S3. Repeat step S2 until each planned route is unaffected by weather, thus completing the route planning.

[0055] In an optional embodiment, the color value of each pixel in the meteorological distribution map corresponds to the meteorological conditions at the corresponding location. The meteorological distribution map is divided into several grids of the same size. When the color value of any pixel in the grid exceeds a preset threshold, the location corresponding to that pixel is considered to have dangerous weather, and the grid is designated as an impassable grid. All impassable grids are combined to form an impassable area.

[0056] Based on the pixel color values ​​in the image, each pixel is divided into red, yellow, and blue pixels. Red and yellow pixels indicate that the location has dangerous weather, while blue pixels indicate that the weather at that location is risky, and there is a certain risk when an aircraft passes over that location.

[0057] In addition, the meteorological distribution map also includes man-made no-passage zones, and the impassable areas also include the no-passage zones.

[0058] In an optional embodiment, in step S1, the specific implementation of determining whether each planned flight path is affected by the weather based on the meteorological distribution map is as follows: for each planned flight path, if any part of the planned flight path does not cross an impassable area, then the planned flight path is a normal flight path; if any part of the planned flight path crosses an impassable area, then the planned flight path is an abnormal flight path.

[0059] Based on the coordinates of the planned flight track, it is determined whether it is occupied by weather, thereby identifying the planned flight track affected by weather and using it as the object of detour route planning. Unaffected planned flight tracks will not be detour route planned. According to the flight plan, flights that will take off and land using these affected planned flight tracks during the predicted period are the affected flights, that is, flights that cannot take off and land according to the original planned flight track.

[0060] Specifically, for each planned flight path, based on the flight plan, it is determined which flights intend to use the planned flight path for takeoff or landing within the half-hour time interval before and after the predicted time. These flights are considered to be affected flights.

[0061] In one specific embodiment, a predicted weather radar image is obtained from the aviation meteorological department. This weather radar image contains latitude and longitude coordinates and is divided into grids of 2km*2km size. Pixel color values ​​are read, and impassable areas are divided according to the pixel color values. The planned flight path is divided into several segments according to the planned flight path points. It is then determined whether each segment crosses the red and yellow weather grids. If none of the segments cross, the flight path does not require path planning; otherwise, detour path planning is required. The affected planned flight paths are sorted according to the number of affected flights.

[0062] In an optional embodiment, in step S2, the specific implementation of planning several pre-selected flight paths to avoid weather influences based on the A* algorithm and meteorological distribution map is as follows: the abnormal flight path includes N track points, which divide the abnormal flight path into N-1 segments. All segments of the abnormal flight path that pass through impassable areas are marked as dangerous segments. Dangerous segments that continuously pass through impassable areas are merged into the same dangerous segment. For each dangerous segment k, path planning is performed, which includes:

[0063] Select the (k-1)th waypoint as the planning start point A and the (k+1)th waypoint as the planning end point S. Perform path planning from the planning start point A to the planning end point S according to the A* algorithm.

[0064] In addition, when the k-th track point is the starting point of the planned track, the starting point of the planned track is directly used as the planned starting point A. If the planned starting point A is occupied by weather, an unoccupied point near point A is found as the new starting point.

[0065] If the k-th track point is the endpoint of the planned track, then the endpoint of the planned track is directly taken as the planned endpoint S. Similarly, if the planned endpoint S is occupied by weather, then an unoccupied point near point S is found as the new endpoint.

[0066] In an optional embodiment, the path planning from the planning starting point A to the planning ending point S according to the A* algorithm is specifically implemented as follows: the objective function of the A* algorithm is:

[0067] And satisfy ,

[0068] in, Point , The distance between them, where m represents the number of waypoints and L represents the track. Indicates an area that is impassable;

[0069] The optimization cost function of the A* algorithm is:

[0070] f(n) = g(n) + h(n)

[0071] Where f(n) represents the estimated cost function from the planning starting point A to the current node n, and then from the current node n to the planning endpoint S, g(n) is the actual cost function from the flight starting point A to the current node n, and h(n) is the heuristic function, which is the estimated cost function from the current node n to the planning endpoint S.

[0072] The actual cost function g(n) is:

[0073] g(n) =

[0074] in, This represents the coordinates of the i-th point from the starting point A to the current point n. When i=0, Starting point A of the plan, Point , The distance between them.

[0075] The A* algorithm aims to plan a detour route with the shortest path as the objective and avoiding weather grid constraints. By combining heuristic search and a cost function, the A* algorithm effectively reduces the number of nodes to be searched, thus quickly finding the optimal path. This is crucial for route planning, as it typically requires finding routes with minimal fuel consumption, shortest flight time, or lowest risk. Furthermore, the A* algorithm is suitable for dynamic environments. By updating the cost and heuristic values ​​of nodes in real time, the A* algorithm can replan routes during flight, adapting to weather changes, airspace restrictions, or unforeseen events.

[0076] In an optional embodiment, the method further includes: for each dangerous segment of each abnormal trajectory, setting different planning start points and / or planning end points, and using the A* algorithm to perform path planning to obtain several different pre-selected trajectories.

[0077] Due to the characteristics of the A* algorithm and grid partitioning, each update step is along the grid boundary, resulting in a jagged and uneven path. Therefore, a smoothing operation is needed to smooth the planned path.

[0078] In an optional embodiment, the method further includes smoothing the preselected track, the smoothing specifically including:

[0079] For each segment of the pre-selected route, if the straightened segment will not pass through an impassable area, then the segment will be straightened.

[0080] The principle of the above-mentioned smoothing process is the principle of straightening curves to ensure that the flight path is as smooth as possible, thereby saving the distance traveled by the aircraft and avoiding the waste of navigation resources.

[0081] In an optional embodiment, in step S2, the calculation of the comprehensive score for each pre-selected flight path based on the meteorological distribution map is specifically implemented by the following method: the comprehensive score includes safety indicators, efficiency indicators, regularity indicators, and conflict indicators.

[0082] In an optional embodiment, each pixel of the weather distribution map is further divided into safe weather and risky weather based on its color value. When risky weather exists within a grid but no dangerous weather exists, the grid is classified as a risky grid. The formula for calculating the safety index s is as follows:

[0083]

[0084] Where L is the set of grids traversed by the trajectory. The set of all grids in the impassable area. The set of all risk grids;

[0085] Specifically, red and yellow weather indicates hazardous weather, blue weather indicates risky weather, and all other weather conditions are considered safe. This means that the pre-selected route has not passed through any weather conditions, in which case s=1. This indicates that the selected route has passed through hazardous weather conditions, thus lowering its safety index and posing a certain risk. This means that the pre-selected route has crossed dangerous weather, violating the principle that crossing dangerous weather is not allowed, and in this case s=0.

[0086] The efficiency index d is calculated using the following formula:

[0087]

[0088] in, Indicates the length of the pre-selected route. This indicates the length of the original planned flight path corresponding to the pre-selected flight path. 'd' actually represents the detour distance. When the distance is zero, the detour distance is taken as 0; otherwise, the actual detour distance is used for calculation.

[0089] For each point on the pre-selected track, when the point on the pre-selected track ,point The distances to the originally planned flight paths were all less than the preset parameters. At that time, the recording point ,point Distance between The formula for calculating the regularity index r is:

[0090]

[0091] in, This indicates the length of the original planned track corresponding to the preselected track, and r indicates the degree of conformity between the preselected track and the planned track. Considering that the actual flight distance may be greater than the flight distance of the original planned track, the value of r may be greater than 1, indicating that the regularity of the preselected track is very good.

[0092] The formula for calculating the conflict index c is as follows:

[0093]

[0094] in, Indicates the pre-selected track. This represents the j-th planned route out of all planned routes. express The number of intersections between them, c represents The number of intersections with all existing planned tracks is used to assess the conflict between the pre-selected track and existing tracks.

[0095] In an optional embodiment, the formula for calculating the comprehensive score is:

[0096]

[0097] In the formula:

[0098]

[0099] Where s represents the safety index, d represents the efficiency index, c represents the conflict index, ad represents the weight value of the efficiency index, ar represents the weight value of the regularity index, cr represents the weight value of the conflict index, D is the converted value of the efficiency index, R is the converted value of the regularity index, and C is the converted value of the conflict index.

[0100] In one specific embodiment, the weight value ad of the efficiency index is 0.4, the weight value ar of the regularity index is 0.3, and the weight value cr of the conflict index is 0.3.

[0101] For the safety indicator s, it is a veto. If the planned route crosses the red and yellow areas, s=0 and the comprehensive evaluation value e=0; if it crosses the blue weather area, then s=0.95. For the efficiency indicator, if the detour distance is less than or equal to 0, the indicator score D is 100 points. Otherwise, for every additional 1km of detour, the score is reduced by 1. For the regularity indicator, the indicator score R is 100 points. When r>=1, R=100 points; otherwise, R=r*100 points. For the conflict indicator, 2 points are deducted for each intersection.

[0102] The embodiments disclosed in this specification are merely illustrative of one aspect of the invention, and the scope of protection of the invention is not limited to these embodiments. Any other functionally equivalent embodiments fall within the scope of protection of the invention. Those skilled in the art can make various other corresponding changes and modifications based on the technical solutions and concepts described above, and all such changes and modifications should fall within the scope of protection of the claims of this invention.

Claims

1. A method for planning and evaluating flight detour routes under adverse weather conditions, characterized in that, Includes the following steps: S1. Obtain the weather distribution map and all planned flight tracks. Based on the weather distribution map, determine whether each planned flight track is affected by the weather. Planned flight tracks affected by the weather are classified as abnormal flight tracks, and planned flight tracks not affected by the weather are classified as normal flight tracks. S2. For each abnormal flight path, based on the A* algorithm and the weather distribution map, plan several pre-selected flight paths to avoid weather influences. Calculate the comprehensive score of each pre-selected flight path based on the weather distribution map, select the pre-selected flight path with the highest score to replace the abnormal flight path, and classify the replaced abnormal flight path as a normal flight path. The specific implementation method for calculating the comprehensive score of each pre-selected flight path based on the meteorological distribution map includes: the comprehensive score includes safety indicators, efficiency indicators, regularity indicators, and conflict indicators. The formula for calculating the comprehensive score is as follows: In the formula: Where s represents the safety index, d represents the efficiency index, c represents the conflict index, ad represents the weight value of the efficiency index, ar represents the weight value of the regularity index, and cr represents the weight value of the conflict index. Each pixel in the meteorological distribution map is further divided into safe, risky, and dangerous weather based on its color value. When risky weather exists within a grid but dangerous weather does not, the grid is classified as a risky grid. The formula for calculating the safety index s is as follows: Where L is the set of grids traversed by the trajectory. The set of all grids in the impassable area. The set of all risk grids; The efficiency index d is calculated using the following formula: in, This indicates the length of the pre-selected route. This indicates the length of the original planned route corresponding to the preselected route; For each point on the pre-selected track, when the point on the pre-selected track ,point The distances to the originally planned flight paths were all less than the preset parameters. At that time, the recording point ,point Distance between The formula for calculating the regularity index r is: in, This indicates the length of the original planned track corresponding to the preselected track; The formula for calculating the conflict index c is as follows: in, Indicates the pre-selected track. This represents the j-th planned route out of all planned routes. express The number of intersections between them; S3. Repeat step S2 until each planned route is unaffected by weather, thus completing the route planning.

2. The method for flight detour planning and evaluation under severe weather conditions according to claim 1, characterized in that, The color value of each pixel in the meteorological distribution map represents the meteorological conditions at that location. The meteorological distribution map is divided into several grids of the same size. When the color value of any pixel in a grid exceeds a preset threshold, the location of that pixel is considered to have dangerous weather, and the grid is designated as an impassable grid. All impassable grids are combined to form an impassable area.

3. The method for flight detour planning and evaluation under severe weather conditions according to claim 2, characterized in that, In step S1, the specific implementation of determining whether each planned flight path is affected by the weather based on the meteorological distribution map is as follows: for each planned flight path, if any part of the planned flight path does not cross an impassable area, then the planned flight path is a normal flight path; if any part of the planned flight path crosses an impassable area, then the planned flight path is an abnormal flight path.

4. The method for flight detour planning and evaluation under severe weather conditions according to claim 3, characterized in that, In step S2, the specific implementation of planning several pre-selected flight paths to avoid weather influences based on the A* algorithm and meteorological distribution map is as follows: the abnormal flight path includes N track points, which divide the abnormal flight path into N-1 segments. All segments of the abnormal flight path that pass through impassable areas are marked as dangerous segments. Dangerous segments that continuously pass through impassable areas are merged into the same dangerous segment. For each dangerous segment k, path planning is performed, which includes: Select the (k-1)th waypoint as the planning start point A and the (k+1)th waypoint as the planning end point S. Perform path planning from the planning start point A to the planning end point S according to the A* algorithm.

5. The method for flight detour planning and evaluation under severe weather conditions according to claim 4, characterized in that, The specific implementation of the path planning from the planning start point A to the planning end point S using the A* algorithm is as follows: The objective function of the A* algorithm is: And satisfy , in, Point , The distance between them, where m represents the number of waypoints and L represents the track. Indicates an area that is impassable; The optimization cost function of the A* algorithm is: f(n) = g(n) + h(n) Where f(n) represents the estimated cost function from the planning starting point A to the current node n, and then from the current node n to the planning endpoint S, g(n) is the actual cost function from the flight starting point A to the current node n, and h(n) is the heuristic function, which is the estimated cost function from the current node n to the planning endpoint S. The actual cost function g(n) is: g(n)= in, This represents the coordinates of the i-th point from the starting point A to the current point n. When i=0, Starting point A of the plan, Point , The distance between them.

6. The method for flight detour planning and evaluation under severe weather conditions according to claim 5, characterized in that, Also includes: For each dangerous segment of each abnormal trajectory, different planning start points and / or planning end points are set, and the A* algorithm is used for path planning to obtain several different pre-selected trajectories.

7. The method for flight detour planning and evaluation under severe weather conditions according to claim 5, characterized in that, It also includes smoothing the pre-selected track. The smoothing process specifically includes: for each segment of the pre-selected track, if the segment will not pass through an impassable area after being straightened, then the segment will be straightened.

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