Airline path calculation and anti-collision method for low-altitude aircraft

Abstract

The invention is suitable for the technical field of low-altitude airspace aircraft flight, and provides a low-altitude aircraft route path calculation and anti-collision method, which comprises the following steps: acquiring three-dimensional size data of an aircraft, and determining an earth grid level corresponding to the current aircraft according to a maximum size value; establishing a path data set; and calculating a grid set passed by the flight path. During anti-collision analysis, according to the code of the grid unit where the current aircraft is located and the center point distance, the space relation between the grid units is judged, and then the space relation of the aircraft can be obtained. According to the method, the path is not displayed in a coordinate point form, and the route path is displayed in a three-dimensional space earth grid unit form, so that the path display is more visual, the position is more realistic and more comprehensive, and subsequent collision analysis is facilitated; and the problem of anti-collision detection of the aircraft in the low-altitude airspace flight process is solved by judging the spatial relationship between the grid cells where the aircraft is located.

Description

Technical Field

[0001] The invention belongs to the technical field of low-altitude aircraft flight, and in particular relates to a route path calculation and collision avoidance method for a low-altitude aircraft. Background Art

[0002] As the number of aircraft in low-altitude airspace continues to increase, how to effectively prevent collisions between aircraft has become a key technical problem that urgently needs to be solved in the development of the low-altitude industry. This challenge is not only related to flight safety, but also directly affects the sustainable development of the low-altitude economy and the efficiency of the entire airspace management. In this context, various advanced flight monitoring technologies, intelligent collision avoidance systems, and autonomous UAV flight technologies are being actively developed and applied in order to build a safer, more efficient and intelligent low-altitude flight environment.

[0003] For the anti-collision research of low-altitude aircraft, the first thing to do is to obtain the flight path of the aircraft. In the existing technology, the longitude and latitude coordinates are generally recorded directly, but the coordinate data cannot directly reflect the position of the aircraft, especially only the position at the sampling time point can be recorded, and the path information between the two sampling points cannot be reflected. In addition, when calculating the anti-collision between aircraft, generally only the coordinate distance is calculated, and it is not possible to issue warnings separately according to different position conditions. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to provide a route path calculation and collision avoidance method for low-altitude aircraft, aiming to solve the technical problems in the prior art that the path calculation display is not intuitive and complete and the collision avoidance warning is not specific enough.

[0005] The present invention adopts the following technical solution: On the one hand, the method for calculating the route path of the low-altitude aircraft comprises the following steps: Step S1, obtaining the three-dimensional size data of the aircraft, and determining the earth grid level corresponding to the current aircraft with the maximum size according to the earth grid unit size of the earth grid level; Step S2, obtaining the flight path data of the aircraft to establish a path data set, wherein the flight path data is the geospatial coordinate data at each time point; Step S3: Calculate the grid set of the current earth grid level through which the aircraft flight path passes according to the path data set.

[0006] Also included: Step S4: In three-dimensional space, the grid set that the aircraft passes through is displayed as the flight path of the aircraft.

[0007] On the other hand, the anti-collision method for the low-altitude aircraft includes the route path calculation method for the low-altitude aircraft, and further includes: Step S5: For the two aircrafts F1 and F2, obtain the position point at time t from the grid set of the corresponding route path and The grid cell and , and get the corresponding code and ; Step S6: and The relationship between the grid cells and The center point distance is used to determine the grid unit and The spatial relationship between , including overlap, inclusion, adjacency, and separation; Step S7: If the grid cell and The spatial relationship between If the grid cells are overlapped or contained, aircraft F1 and F2 will collide. and The relationship between If the grid cells are adjacent, there is a risk of collision between aircraft F1 and F2. and The relationship between If the two aircrafts F1 and F2 are in a separation relationship, there will be no collision between them.

[0008] The beneficial effects of the present invention are as follows: in the technical solution of the present invention, the space is divided according to the earth grid, the earth grid units that the aircraft route path passes through are recorded, a grid set is generated, and the path is not displayed in the form of coordinate points, but in the form of earth grid units in three-dimensional space, so that the path display is more intuitive, the position is more realistic and comprehensive, and it is also conducive to subsequent collision analysis. In addition, the present invention solves the problem of anti-collision detection of aircraft during flight in low-altitude airspace by judging the spatial relationship between the grid units where the aircraft are located and analyzing whether a collision will or may occur between low-altitude aircraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 is a flow chart of a method for calculating a low-altitude aircraft route path provided by an embodiment of the present invention; Figure 2 It is a schematic diagram of the earth grid division at different levels; Figure 3 It is a schematic diagram of the situation where the grid cell encodings corresponding to two points are the same; Figure 4 It is a schematic diagram of different situations of traversing the grid cell encoding corresponding to two points; Figure 5 is a flow chart of a low-altitude aircraft anti-collision method provided by an embodiment of the present invention; Figure 6 It is a planar diagram of the spatial relationship of earth grid units at the same level and different levels. DETAILED DESCRIPTION

[0010] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0011] In order to illustrate the technical solution of the present invention, a specific embodiment is provided below for illustration.

[0012] Embodiment 1: like Figure 1 As shown, this embodiment provides a method for calculating a low-altitude aircraft route path, comprising the following steps: Step S1, obtaining the three-dimensional size data of the aircraft, and determining the earth grid level corresponding to the current aircraft with the maximum size according to the earth grid unit size of the earth grid level.

[0013] Low-altitude aircraft have three dimensions: length, width and height. Assume that the length, width and height of the current aircraft are , maximum aircraft size dF1= , where max is the maximum value.

[0014] The earth space is divided into three-dimensional grids of different levels, and the grid units of different levels of earth grids are of different sizes. For example, as a division method, Figure 2 As shown in the figure, the side length of the upper grid unit is twice that of the lower grid unit, that is, one upper grid unit can correspond to 8 lower grid units, and the earth space can be divided into different levels of grid units from top to bottom. Each level divides the entire earth space.

[0015] After the grid is divided, each level of the grid unit has a corresponding size and length. express The next level grid unit, Indicates According to the size dF1 of the aircraft F1 and the size of the earth grid unit, the earth grid level corresponding to the aircraft F1 is determined. .

[0016] if <dF1≤ , then the earth grid level corresponding to the current aircraft is considered to be .

[0017] Step S2: Acquire the flight path data of the aircraft to establish a path data set, wherein the flight path data is the geospatial coordinate data at each time point.

[0018] For example, if there are records of geospatial coordinate data at n time points, the path data set established is: , each geospatial coordinate data in the collection consists of longitude, latitude and altitude data.

[0019] Step S3: Calculate the grid set of the current earth grid level through which the aircraft flight path passes according to the path data set.

[0020] Taking low-altitude aircraft F1 as an example, its path data set is: The specific process of this step is as follows: S31. Traversing path data set Each geospatial coordinate data is taken out in turn, and for the two points currently obtained , , where 1≤i≤n-1, construct the line segment equation between two points : ;

[0021] S32, according to two points and The coordinate data of the two points is used to determine whether they are in the same grid unit and to establish a grid set. The specific process of this step is as follows: 321. Calculate the location of two points Hierarchical Earth Grid Cells and , where Location Hierarchical Earth Grid Cells The calculation method is as follows: ; in, To round up, , , Represents the earth grid unit The ordinal value in the longitude, latitude, and altitude directions in the current level earth grid.

[0022] For point , whose three-dimensional coordinates are Since the earth grid is divided into three-dimensional grids in the reverse direction of longitude, latitude and altitude, the coordinate component is divided by the grid unit size, and then rounded up to get the current point The relative position of the grid cell in the entire earth space.

[0023] 322. Get the Earth grid cells by number and The corresponding codes are and , and the Earth grid cells Add to Grid Collection .

[0024] The earth space division and its coding in this embodiment refer to "Earth Surface Space Grid and Coding" (GJB 8896-2017). Each level of grid cells has a fixed coding method, so the coding of grid cells at different levels is different.

[0025] Therefore, in getting the earth grid unit 、 After the location information is obtained, it is encoded according to the fixed encoding method to obtain the corresponding code and Then Add to Grid Collection middle.

[0026] 323. If , it means that the two points are in the same earth grid unit Inside, at this time Figure 3 As shown, the explanation points arrive The path between them only passes through grid cells Then return to step S31 to traverse the next two adjacent points, that is, take and , and follow the above method to Add to Grid Collection middle.

[0027] if , then explain the point and Point In different grid cells, such as Figure 4 As shown, is the center of the ball, For the radius of the sphere, construct the sphere equation : ; Simultaneous Line Segment Equations and spherical equation , find the intersection point , then point and Point Constructing the equation of a line segment Then repeat step S32 to determine the point and Point Whether they are in the same grid unit (i.e., whether the corresponding codes are the same); if they are in the same grid unit (in the figure, and In the same grid cell), the point Corresponding Earth grid cell Add to Grid Collection In the process, if the grid cells are in different grid units, the ball equation and line segment equation are constructed again for judgment, and the grid set is continuously updated.

[0028] Therefore, through the above judgment method, each time two adjacent points are taken, the starting point and the grid cells between the two points are added to the grid set. middle.

[0029] S33. After the path data set traversal is completed, a final grid set representing the flight path of the aircraft is obtained.

[0030] Step S4: In three-dimensional space, the grid set that the aircraft passes through is displayed as the flight path of the aircraft.

[0031] In order to facilitate the display of the path, in this embodiment, the aircraft displays each grid unit in the grid set on the three-dimensional space interface as the route path of the aircraft. This display method can more intuitively observe the position of the aircraft, and it is also convenient to display the grid units passed between each sampling point, and the data is richer. Moreover, this grid set lays the foundation for subsequent anti-collision judgment.

[0032] Embodiment 2: This embodiment provides a method for preventing collision of the low-altitude aircraft, such as Figure 5 As shown, the following steps are included: Step S5: For the two aircrafts F1 and F2, obtain the position point at time t from the grid set of the corresponding route path and The grid cell and , and get the corresponding code and .

[0033] When the spatial relationship between two aircrafts F1 and F2 needs to be determined, the grid set corresponding to the route path of aircraft F1 has been obtained in the first embodiment. Similarly, the grid set corresponding to the route path of aircraft F2 can also be obtained. The specific process is not repeated here.

[0034] Although the grid set stores the grid cells where the aircraft is located at each sampling time point and the grid cells that the aircraft passes through between sampling points, and is stored in order, each grid cell in the grid set has time point information, so the grid cell where the position point corresponding to time point t is located can be directly obtained and then encoded, respectively. and .

[0035] Step S6: and The relationship between the grid cells and The center point distance is used to determine the grid unit and The spatial relationship between , including overlap, inclusion, adjacency, and separation.

[0036] Combination Figure 6 As shown in the figure, overlap means that the two grid cells are the same grid cell; inclusion means that one of the small grid cells is in another large grid cell; adjacent means that there is an adjacent face, adjacent edge or adjacent vertex between the two grid cells; separation means that there are no adjacent points, edges or faces between the two grid cells, and they are not in a containment or overlap relationship.

[0037] The specific process of this step is as follows: S61, the level where the aircraft F1 is located is , the level where aircraft F2 is located is , get the grid cells where the two aircraft are located and , according to the earth grid division rules, the grid unit is obtained and The corresponding center point coordinates are ( , , )、 ( , , ), as well as the size of the grid unit side length and angle diagonal length, where the grid unit and The size and side lengths are , The lengths of the diagonals are , ; S62, according to the center point coordinates ( , , )、 ( , , ),calculate and The distance between : ; if ,but To coincide; if and and ,but To be adjacent; if and and ,but For separation; if and and ,but To include, Indicates the encoding Before Bit encoding; if and and ,but To be adjacent; if and and ,but To be adjacent; if and and and ,but For separation; if and and and ,but To be apart.

[0038] Step S7: Determine the collision of the two aircraft based on the spatial relationship: If the grid unit and The spatial relationship between If the grid cells are overlapped or contained, aircraft F1 and F2 will collide. and The relationship between If the grid cells are adjacent, there is a risk of collision between aircraft F1 and F2. and The relationship between If the two aircrafts F1 and F2 are in a separation relationship, there will be no collision between them.

[0039] Therefore, through the above judgment method, according to the size of the aircraft in the low-altitude airspace, a grid set of the route path is obtained, and then according to the spatial relationship between the grid units at different time points, the aircraft flying in the low-altitude airspace can be subjected to collision analysis, which helps to improve the flight safety of aircraft in the low-altitude airspace.

[0040] Embodiment three: This embodiment provides a method for preventing collision of low-altitude aircraft. The difference between this embodiment and the second embodiment is that, when analyzing the spatial relationship between the two aircraft at time point t, the second embodiment directly uses the grid cells where the instantaneous positions of the two aircraft at time point t are located to perform position analysis; this embodiment further uses the grid cells that the two aircraft pass through from time point t-1 to time point t to perform position analysis between each two, that is, calculate and The distance between It is the shortest distance between the center points of the grid cells that the two aircraft pass through in the time period corresponding to the time point. This method is also more accurate in analyzing the collision state.

[0041] In summary, the present invention firstly represents the route path of the aircraft by obtaining the grid cells through which the flight path of the aircraft passes, obtains a grid set, and then solves the technical problem of whether the aircraft collides during flight in low-altitude airspace by judging the spatial relationship between the aircraft.

[0042] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for calculating a low-altitude aircraft route path, characterized in that: The route path calculation method comprises the following steps: Step S1, obtaining the three-dimensional size data of the aircraft, and determining the earth grid level corresponding to the current aircraft with the maximum size according to the earth grid unit size of the earth grid level; Step S2, obtaining the flight path data of the aircraft to establish a path data set, wherein the flight path data is the geospatial coordinate data at each time point; Step S3: Calculate the grid set of the current earth grid level through which the aircraft flight path passes according to the path data set.

2. The method for calculating the route path of a low-altitude aircraft as claimed in claim 1, characterized in that: The route path calculation method also includes the following steps: Step S4: In three-dimensional space, the grid set that the aircraft passes through is displayed as the flight path of the aircraft.

3. The method for calculating the route path of a low-altitude aircraft as claimed in claim 2, characterized in that: In step S1, the length, width and height three-dimensional data of the current aircraft are , the maximum size of the aircraft dF1= , where max is the maximum value. If <dF1≤ , then the earth grid level corresponding to the current aircraft is considered to be ,in for The next level grid unit, Indicates Earth grid unit The size of the length.

4. The method for calculating the route path of a low-altitude aircraft as claimed in claim 3, characterized in that: In step S2, the path data set established is: ； The set contains geospatial coordinate data of n time points, and each geospatial coordinate data consists of longitude, latitude and altitude data.

5. The method for calculating the route path of a low-altitude aircraft as claimed in claim 4, characterized in that: The specific process of step S3 is as follows: S31, traverse each geospatial coordinate data of the path data set, take out two adjacent points in turn, and for the two points currently obtained , where 1≤i≤n-1, construct the line segment equation between two points : ； S32, according to two points and The coordinate data of two points is used to determine whether they are in the same grid unit and to establish a grid set. The specific process is as follows:

321. Calculate the location of two points Hierarchical Earth Grid Cells and , where the point Location Hierarchical Earth Grid Cells The calculation method is as follows: ； in, To round up, , , Represents the earth grid unit The ordinal value in the longitude, latitude, and altitude directions in the current level earth grid; 322. Get the Earth grid cells by number and The corresponding codes are and , and the Earth grid cells Add to Grid Collection ; 323. If , it means that the two points are in the same earth grid unit Then return to step S31 to traverse the next two adjacent points; if , then explain the point and Point In different grid units, For the center of the ball, For the radius of the sphere, construct the sphere equation : ； Simultaneous Line Segment Equations and spherical equation , find the intersection point , then point and Point Constructing the equation of a line segment Then repeat step S32 to determine the point and Point Are they in the same grid cell? If so, the point Corresponding Earth grid cell Add to Grid Collection In the process, if the grid cells are different, the ball equation and line segment equation are constructed again for judgment, and the grid set is continuously updated; S33. After the path data set traversal is completed, a final grid set representing the flight path of the aircraft is obtained.

6. A method for preventing collision of a low-altitude aircraft, characterized in that: The anti-collision method comprises the low-altitude aircraft route path calculation method according to any one of claims 1 to 5, and further comprises the following steps: Step S5: For the two aircrafts F1 and F2, obtain the position point at time t from the grid set of the corresponding route path and The grid cell and , and get the corresponding code and ; Step S6: and The relationship between the grid cells and The center point distance is used to determine the grid unit and The spatial relationship between , including overlap, inclusion, adjacency, and separation; Step S7: If the grid unit and The spatial relationship between If the grid cells are overlapped or contained, aircraft F1 and F2 will collide. and The relationship between If the grid cells are adjacent, there is a risk of collision between aircraft F1 and F2. and The relationship between If the two aircrafts F1 and F2 are in a separation relationship, there will be no collision between them.

7. The anti-collision method for low-altitude aircraft as claimed in claim 6, characterized in that: The specific process of step S6 is as follows: S61, the level where the aircraft F1 is located is , the level of aircraft F2 is , get the grid cells where the two aircraft are located and , according to the earth grid division rules, the grid unit is obtained and The corresponding center point coordinates are ( ， ， ) 、 ( ， ， ), as well as the size of the grid unit side length and angle diagonal length, where the grid unit and The size and side lengths are 、 The lengths of the diagonals are 、 ; S62, according to the center point coordinates ( ， ， ) 、 ( ， ， ),calculate and The distance between : ； if ,but To coincide; if and and ,but To be adjacent; if and and ,but To be adjacent; if and and ,but For separation; if and and ,but To include, Indicates the encoding Before Bit encoding; if and and ,but To be adjacent; if and and ,but To be adjacent; if and and and ,but For separation; if and and and ,but To be apart.

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