Method for generating irregular meteorological radar echo isoline evasion area
By generating irregular weather radar echo contour lines to avoid areas, the problem of static meteorological data in traditional flight path planning is solved, and efficient simulation of dynamic weather avoidance areas is achieved, improving the accuracy and response speed of flight path planning.
Patent Information
- Application Number
- CN202510988114.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-17
- Publication Date
- 2025-11-07
AI Technical Summary
Traditional flight path planning relies on static meteorological data, which cannot accurately describe the dynamic changes of complex meteorological systems. This makes it difficult to achieve the globally optimal path in complex meteorological environments, resulting in limited response speed.
An irregular meteorological radar echo contour line avoidance zone generation method is adopted. By initializing and designing irregular meteorological avoidance zones, their motion patterns are simulated. Gaussian processes are used to model the dynamic changes of the meteorological system, generating multi-layered irregular polygons to reflect the natural life cycle and motion patterns of the meteorological system.
It achieves highly realistic simulation of dynamic weather avoidance zones, improving the accuracy and response speed of flight path planning, and reducing the cost and risk of real-world testing.
Smart Images
Figure CN120913448A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to a method for generating a simulated dynamic meteorological avoidance area in a flight plan generation system, and belongs to the technical fields of air traffic control and aircraft collaborative flight path planning. BACKGROUND
[0002] With the rapid development of the civil aviation industry, the number of flights continues to grow, and the influence of air route congestion and adverse weather conditions on flight safety and efficiency is increasingly significant. Dangerous weather such as thunderstorms, cumulonimbus clouds, turbulence, and volcanic ash not only threaten the safety of aircraft, but also can cause flight delays, rerouting, and even cancellation, resulting in significant economic losses. Traditional flight path planning mainly relies on pilot experience and dynamic command from air traffic control departments, but in complex weather conditions, manual decision-making often fails to achieve a globally optimal path, and the response speed is limited. Therefore, collaborative flight path planning is increasingly urgent. The application provides a method for generating a simulated dynamic meteorological radar echo contour avoidance area in a civil aviation flight plan generation system, which aims to provide simulated meteorological avoidance area data for collaborative four-dimensional flight path planning of aircraft based on flight operation, airspace environment, and meteorological conditions.
[0003] In the process of civil aviation flight planning, meteorological avoidance is an important link to ensure flight safety. Traditional meteorological avoidance area processing methods mainly rely on static meteorological data and cannot accurately reflect the dynamic characteristics of the meteorological system. The existing technology has the following disadvantages:
[0004] 1. The meteorological avoidance area is usually represented by a fixed circle or a simple polygon, which cannot accurately describe the actual shape of a complex meteorological system;
[0005] 2. There is a lack of simulation of the dynamic evolution process of the meteorological system, including movement, rotation, and shape change, which cannot reflect the real-time shape of the meteorological avoidance area during flight. SUMMARY
[0006] The application provides an irregular meteorological radar echo contour avoidance area generation method, which solves the problems disclosed in the background art.
[0007] To solve the above technical problems, the technical solution adopted by the application is:
[0008] An irregular meteorological radar echo contour avoidance area generation method, the main steps of which include:
[0009] Step 1: initialization of meteorological radar echo avoidance area construction
[0010] Step 1.1: initialization of meteorological avoidance area airspace
[0011] Initialization of weather radar echo contour avoidance zone includes initialization of latitude and longitude range of airspace, setting upper limit of avoidance zone number, initialization of running time, the steps are shown in the following pseudo code:
[0012]
[0013]
[0014] After setting the life state of the avoidance zone, some are in the growth stage and the rest are in the mature stage to simulate the growth, maintenance and gradual decline of the cloud cluster of the weather avoidance zone, the steps are shown in the following code:
[0015]
[0016] Step 1.2: Set the intensity level of the avoidance zone
[0017] First, generate the center point of the weather avoidance zone and ensure that it is within the latitude and longitude limit of the airspace, then set the intensity level of the weather avoidance zone to low, medium and core layer, the low intensity layer is the main layer, and the nested sub-area is generated by scaling the main layer to ensure topological consistency. Among them, the generation of the center point, the size of the avoidance zone and the scaling ratio of each intensity layer are set to random values between (0.95, 1.05) to simulate the uncertainty of natural weather.
[0018] Step 1.3: Design irregular weather avoidance zone
[0019] The shape parameters of the weather radar echo weather avoidance zone include center point, average radius, irregularity, spiculation degree and irregular polygon vertex number. The pseudo code is as follows:
[0020]
[0021]
[0022] Step two: design the motion form of the avoidance zone and simulate the motion process
[0023] Step 2.1: Design the dynamic parameter motion form of the avoidance zone
[0024] Design the dynamic parameter motion form of the avoidance zone, mainly including the change of weather intensity layer in the process of weather avoidance zone movement, rotation and scaling.
[0025] The main formula of the movement process is:
[0026]
[0027] Where d_long represents the distance the longitude coordinates of each point in the weather avoidance zone polygon have moved along the longitude direction, d_lat represents the distance the latitude coordinates of each point in the avoidance zone polygon have moved along the latitude direction, and zoneV long zoneV lat This represents the movement speed along the longitude and latitude of the avoidance zone, randomly selected in the range (-0.02, 0.02) in units of longitude and latitude. k1 and k2 represent standardization factors; considering the proportion of distance to my country's latitude and longitude, both k1 and k2 are set to 0.05. elapsed The time interval is determined by the running time of the simulated motion process.
[0028] The main formula for the rotation process is:
[0029]
[0030] Where r_long represents the longitude coordinates with (long0, lat0) as the origin after rotation, r_lat represents the latitude coordinates with (long0, lat0) as the origin after rotation, long0 represents the longitude coordinates of the rotation center, and lat0 represents the latitude coordinates of the rotation center. After obtaining the values of r_long and r_lat, long0 and lat0 need to be added respectively to obtain the transformed longitude and latitude coordinates long. new lat new θ represents the rotation angle, long represents the longitude coordinates before transformation, and lat represents the longitude coordinates before transformation.
[0031]
[0032] Where long represents the longitude coordinates before transformation, lat represents the longitude coordinates before transformation, and long new lat represents scaled longitude coordinates. new This represents the scaled latitude coordinates, fact long The scaling factor representing the longitude direction, fact lat The scaling factor represents the latitude direction.
[0033] The pseudocode for implementing the above motion pattern is shown below:
[0034]
[0035] Step 2.2: Design the Gaussian process for the movement of the weather avoidance zone
[0036] The displacement and morphological change of the avoidance zone can be regarded as a random function in continuous space-time coordinates, which can be modeled by a Gaussian process. The covariance function (kernel function) can capture the spatial correlation of the meteorological system (such as the similar movement trend of adjacent regions) and the smoothness in time (such as the path continuity caused by inertial motion). The mean function of the Gaussian process can reflect the deterministic trend of the background environment field (such as the wind field guide), and the parameters (such as the length scale and variance) of the covariance function can quantify the local intensity and decay rate of meteorological uncertainty. Therefore, the designed composite kernel is used to simulate the movement of the meteorological avoidance zone, which provides a mathematical representation of the random movement of the meteorological avoidance zone that takes into account both physical constraints and statistical flexibility.
[0037] Step 2.3: Simulate the movement process of the meteorological avoidance zone
[0038] The simulation of the movement process of the meteorological radar echo contour avoidance zone includes the steps in step 2.2 and also includes limiting the maximum scaling size of the meteorological radar echo contour avoidance zone, detecting whether the avoidance zone collides with the boundary, generating, diffusing and decaying the meteorological avoidance zone by Gaussian process simulation.
[0039] Step three: encapsulation function and visualization
[0040] The encapsulation function is set to output the meteorological avoidance zone information in geojson format containing the latitude and longitude position every 20s, and the meteorological avoidance zone region output combines the characteristics of the three avoidance zone meteorological intensity layers, and the pseudo code is as follows:
[0041]
[0042] According to the latitude and longitude range of China, the encapsulation function is visualized, and the movement of the meteorological radar echo contour avoidance zone in the airspace range of China with a total simulation time of 600s and a time interval of 20s is simulated to intuitively show the movement pattern of the meteorological avoidance zone.
[0043] The beneficial effects of the present application are:
[0044] The generated simulated meteorological avoidance zone effectively simulates the natural life cycle and movement law of the meteorological system through multi-layer irregular polygon modeling, and the dynamic parameter control and boundary intelligent response mechanism based on Gaussian process make it present the continuous change characteristics similar to real weather phenomena, avoiding the mechanical movement mode, ensuring the behavior rationality while maintaining randomness, and realizing the highly simulated dynamic meteorological avoidance zone simulation. This highly realistic dynamic simulation provides a reliable simulation environment for aviation path planning, meteorological warning system testing and intelligent obstacle avoidance algorithm training, significantly improves the development efficiency and test accuracy of related systems, and reduces the cost and risk of real scene testing. BRIEF DESCRIPTION OF DRAWINGS
[0045] Figure 1 Technical roadmap of the method of the present application;
[0046] Figure 2 Simulation experiment results of the method of the present application. DETAILED DESCRIPTION
[0047] The present application will be further described below with reference to the accompanying drawings. The following examples are only used to more clearly illustrate the technical solutions of the present application, and cannot be used to limit the protection scope of the present application.
[0048] As shown in the figure, a method for generating irregular weather radar echo contour avoidance area, comprising the following main steps: Figure 1 Step 1: initialization of weather radar echo avoidance area construction, limiting the generation of airspace range; Step 2: design the motion form of the avoidance area and simulate the motion process; Step 3: encapsulate the function to output the information of the weather avoidance area in geojson format.
[0049] Step 1: initialization of weather radar echo avoidance area construction:
[0050] The simulated weather avoidance area designed in this paper can generate airspace range in the airspace of our country, and can provide the required weather avoidance area data for the simulation of the cooperative four-dimensional flight path planning of the aircraft in the civil aviation industry. The weather avoidance area is generally a dynamically delimited airspace area, which is used to identify dangerous weather such as thunderstorms, cumulonimbus clouds, squall lines, etc. that need to be avoided, and its core attributes include: geographical range, vertical range, time validity, danger level, etc. In order to simplify the simulation situation and flight operation instructions and plans, this paper only simulates two-dimensional weather avoidance area, but sets three intensity layers of avoidance area to simply represent the three-dimensional characteristics of weather, and the aircraft performs the flying operation around the avoidance area simulated in this paper.
[0051] Step 1.1: initialization of weather avoidance area spatial distribution
[0052] A variety of dangerous weather avoidance area regions are constructed through geographical constraints and randomization algorithms, and the effective range of weather activities is delimited as the longitude and latitude of our country. The generation of the avoidance area will avoid the 5-degree buffer zone (center_lon = random.uniform(min_lon + 5, max_lon - 5)) at the edge of the range to avoid the flight flying logic failure caused by the excessive proximity of the region to the boundary. The core position of each avoidance area is determined by the randomly generated center point, but since in high latitude areas, the movement speed and distribution density of longitude need to be adaptively reduced, therefore a latitude correction factor lon_ratio = np.cos(np.radians(lat_mid)) is introduced, which conforms to the geographical characteristics of the convergence of the earth's surface meridians.
[0053]
[0054] The spatial morphology of the avoidance zone is generated as an irregular polygon by the method generate_irregular_polygon(), whose initial size is determined by the growth state: the growing avoidance zone (growing=True) has a smaller radius (0.9-1.2 degrees), while the mature avoidance zone is generated directly with a larger radius of 1.2-1.8 degrees. This differentiated design simulates the development stage of real meteorological systems - new-born thunderstorm cells usually have a small range but expand rapidly, while mature squall line systems have approached the maximum scale. The polygon vertices are distributed star-like around the center point when generated, and natural irregular edges are formed by random perturbation to avoid mechanical geometric shapes.
[0055] Step 1.2: Initialize meteorological characteristics of meteorological avoidance zones
[0056] In the initialization of meteorological characteristics of meteorological avoidance zones, the system builds weather systems with aviation threat characteristics through multi-parameter coupled modeling. Each avoidance zone is defined by the intensities dictionary with three intensity characteristics: low layer (30-40dBZ) corresponds to ordinary precipitation area, middle layer (40-50dBZ) indicates strong convective development, and high layer (50-70dBZ) simulates strong thunderstorm core with aviation hazards. These intensity values are randomly generated but maintain a reasonable gradient, consistent with the typical characteristics of radar observations in which echo intensity increases with height. The dynamic properties of the avoidance zone fully reflect the essential differences between different weather phenomena - the growing avoidance zone (state='growing') is configured with smaller initial scale (current_scale=0.4-0.6) and faster expansion speed (scale_speed=0.05-0.15), simulating the explosive growth of rapidly developing thunderstorm cells; while the mature avoidance zone (state='mature') has a larger target scale (target_scale=1.3-2.0) and stable structure, corresponding to mature squall line systems. This meteorological feature initialization mechanism not only ensures the physical reasonableness of individual avoidance zones, but also, when batch generated by the initial_zones parameter, can build complex weather scenarios containing different development stages, intensity levels and movement characteristics, providing near-real threat environment modeling for aircraft circumnavigation decision-making.
[0057] Step 1.3: Initialize time evolution of meteorological avoidance zones
[0058] The lifetime of the avoidance zone is recorded by setting a timestamp to facilitate the adjustment of the spatial position, rotation angle, and growth progress of the avoidance zone. The time attributes of the avoidance zone include: creation_time records its generation timestamp, lifetime is randomly set to 300-1200 seconds (5-20 minutes), which covers the typical single cell survival period of convective weather. The evolution stage of the avoidance zone is controlled by state and growth_progress—The initial progress value of the new avoidance zone (growing=True) is 0.0, and its spatial scale will continuously expand at a speed of 0.05-0.15 units / second (scale_speed) to the target value (target_scale) until the progress reaches 1.0 to become a mature state; while the mature avoidance zone initialized directly (growth_progress=1.0) maintains a relatively stable scale, but will continue to move and rotate through velocity and rotation_speed.
[0059] Step two: design the motion form of the avoidance zone and simulate the motion process
[0060] Step 2.1: Design the motion form of the avoidance zone
[0061] The dynamic parameter motion form of the avoidance zone mainly includes the changes of the meteorological intensity layer during the movement, rotation, and scaling process of the meteorological avoidance zone.
[0062] The main formula of the movement process is:
[0063]
[0064] where d_long represents the movement distance of the longitude coordinate of each point of the meteorological avoidance zone polygon in the longitude direction, d_lat represents the movement distance of the latitude coordinate of each point of the avoidance zone polygon in the latitude direction, zoneV long , zoneV lat represent the moving speed of the avoidance zone in the longitude and latitude directions, which are randomly taken in the range of (-0.02, 0.02) in longitude and latitude units, k1 and k2 represent the standardization factors, and k1 and k2 are both taken as 0.05 considering the distance proportion of the longitude and latitude of China, time elapsed represents the time interval, which is determined by the running time when simulating the motion state process.
[0065] The main formula of the rotation process is:
[0066]
[0067] Wherein, r_long represents the longitude coordinate with (long0, lat0) as the origin after rotation, r_lat represents the latitude coordinate with (long0, lat0) as the origin after rotation, long0 represents the longitude coordinate of the rotation center, lat0 represents the latitude coordinate of the rotation center, and after obtaining the values of r_long and r_lat, long and lat are obtained by adding long0 and lat0 respectively to obtain the transformed longitude and latitude coordinates long new 、lat new , θ represents the rotation angle, which is randomly valued, long represents the longitude coordinate before transformation, and lat represents the latitude coordinate before transformation.
[0068]
[0069] Wherein, long represents the longitude coordinate before transformation, lat represents the latitude coordinate before transformation, long new represents the longitude coordinate after scaling, lat new represents the latitude coordinate after scaling, fact long represents the scaling factor in the longitude direction, and fact lat represents the scaling factor in the latitude direction.
[0070] For translational motion, the center position of the weather avoidance area changes over time, so the displacement in the time dimension can be considered to follow a Gaussian distribution, and then the covariance function can be described by a radial basis function to characterize the displacement correlation between adjacent times, and the continuous trajectory of translation is the sample path of the Gaussian process. For rotational motion, the rotation angle of the weather avoidance area changes over time, so the rotation angle can also be considered to follow a Gaussian distribution in the time dimension, and then the covariance can be described by a radial basis function to characterize the correlation of the angle change between adjacent times, and the rotation angle of rotation is the sample angle of the Gaussian process. For scaling motion, a log-Gaussian process is used to avoid negative values, and then the WhiteKernel function that allows small random fluctuations is used to characterize the correlation of the scale factor between adjacent times, and the logarithm of the scale factor is the sample scale factor of the Gaussian process. The RBF kernel can ensure that the speed changes smoothly at adjacent time points, and the white noise model can simulate local wind speed disturbances.
[0071] In summary, a composite function is established to simulate the motion of the weather avoidance area:
[0072]
[0073]
[0074] k const (t,t')=σ 2
[0075]
[0076] where k RBF is the radial basis function kernel, k const is the constant kernel, k white is the white noise kernel, t, t' are input time variables, σ 2 is the amplitude parameter, is the noise parameter, δ(t, t') is the Kronecker function, l is the length scale parameter. To keep the numerical stability, parameter constraints are set: l ∈ [10 -2 , 10 2 ], σ 2 ∈ [10 -3 , 10 3 ],
[0077]
[0078] The composite kernel effectively characterizes the following properties of the evading region motion by the smoothness of the RBF kernel + the noise tolerance of the WhiteKernel: time continuity: strong correlation between the scale changes of adjacent times, smoother translation, rotation, and scaling; state adaptability: different scaling rates in the growth / decay phase; physical reasonableness: avoiding non-physical mutations or negative scaling scales.
[0079] In summary, for translation, rotation, and scaling motion, the following model can be established:
[0080]
[0081] where GP(0, k(t, t')) is the Gaussian process, v(t) is the vector velocity of the meteorological evading region translation, ω(t) is the rotation speed of the meteorological evading region, and logs(t) is the logarithm of the scaling factor.
[0082] Step 2.2: Simulate the motion process of the meteorological evading region
[0083] The simulation of the motion process of the meteorological radar echo contour evading region includes the following steps in addition to step 2.1: limiting the maximum scaling size of the meteorological radar echo contour evading region, detecting whether the evading region collides with the boundary, generating, diffusing, and decaying the meteorological evading region using the Gaussian process. The pseudo code is as follows:
[0084]
[0085] Step three: encapsulate the function and visualize
[0086] The encapsulation function is set to output the weather avoidance area information in geojson format containing the current latitude and longitude position every 20s, wherein the output of the weather avoidance area region is combined with the characteristics of three independent weather avoidance area intensity layers, and then the encapsulation function is visualized according to the latitude and longitude range of China. The movement of the weather radar echo contour avoidance area in the airspace range of China with a total simulation time of 600s and a time interval of 20s is simulated to intuitively show the movement form of the weather avoidance area.
Claims
1. A method for generating irregular weather radar return contour avoidance zones, the method comprising: The method comprises the following steps: Step one: initialize the weather radar echo avoidance zone construction, limit the generated airspace range; Step two: design the motion form of the avoidance zone and simulate the motion process; Step three: encapsulate the function to output the information of the weather avoidance zone in the geojson format.
2. The method of claim 1, wherein the method further comprises: Step one comprises the following steps: initializing the airspace latitude and longitude range of the weather avoidance zone, setting the avoidance zone form parameters and the weather intensity layer.
3. The method of claim 2, wherein the method further comprises: The avoidance zone form parameters include the center point, the average radius, the irregularity degree, the spiculation degree, and the number of irregular polygon vertices. The setting steps of the weather intensity layer are as follows: first, generate the center point of the weather avoidance zone and ensure that it is within the latitude and longitude limit range of the airspace, then set the intensity level of the weather avoidance zone to three layers of low, medium, and core layers, the low intensity layer is the main layer, and the nested sub-region is generated by scaling the main layer.
4. The method of claim 1, wherein the method further comprises: In step two, the dynamic parameters and motion form of the avoidance zone are designed, including the changes of the weather intensity layer in the moving, rotating, and scaling processes; the formulas for moving, rotating, and scaling are respectively: wherein d_long indicates a moving distance of the longitude coordinate of each point of the weather avoidance zone polygon in the longitude direction, d_lat indicates a moving distance of the latitude coordinate of each point of the avoidance zone polygon in the latitude direction, zoneV long indicates a moving speed of the avoidance zone in the longitude direction, zoneV lat indicates a moving speed of the avoidance zone in the latitude direction, k1 and k2 indicate normalization factors, time elapsed indicates a time interval; r_long indicates a longitude coordinate after rotation with (long0, lat0) as the origin, r_lat indicates a latitude coordinate after rotation with (long0, lat0) as the origin, long0 indicates a longitude coordinate of the rotation center, lat0 indicates a latitude coordinate of the rotation center, θ indicates a rotation angle, long indicates a longitude coordinate before transformation, and lat indicates a latitude coordinate before transformation; long new indicates a scaled longitude coordinate, lat new indicates a scaled latitude coordinate, fact long indicates a scaling factor in the longitude direction, fact lat indicates a scaling factor in the latitude direction.
5. The method of claim 4, wherein the method further comprises: In step two, a Gaussian process model is established to simulate the changes of various parameters in the motion process of the weather avoidance zone: Wherein, GP(0, k(t, t')) is a Gaussian process, v(t) is the vector velocity of the weather avoidance zone translation, ω(t) is the rotation speed of the weather avoidance zone, and logs(t) is the logarithm of the scaling factor.
6. The method of claim 1, wherein the method further comprises: In step two, the motion process of the avoidance zone is simulated, which comprises the following steps: limiting the maximum scaling size of the weather radar echo contour avoidance zone, detecting whether the avoidance zone collides with the boundary, simulating the generation, diffusion, and decay of the weather avoidance zone by the Gaussian process.
7. The method of claim 1, wherein the method further comprises: In step three, the output of the weather radar echo contour avoidance zone region is set to merge the independent features of the three weather intensity layers of the avoidance zone, and the data output is updated once every 20s.