A multi-level spatial planning method based on spherical rhombic discrete grid

Abstract

The present invention discloses a multi-level airspace planning method based on a spherical diamond discrete grid, comprising the following steps: Step 1: In an airspace management system, based on a spherical latitude and longitude coordinate system and incorporating a regular icosahedral spherical diamond discrete grid, convert airspace coordinate information from an isotropic coordinate system to a spherical rectangular coordinate system; Step 2: Subdividing the regular icosahedral diamond grid; Step 3: Establishing an airspace coordinate global coding system to perform global positioning coding on airspace coordinate points, thereby completing multi-level airspace planning based on the spherical diamond discrete grid; Step 4: In the airspace management system, aircraft within the managed airspace are managed based on the global positioning coding described in Step 3. This method effectively addresses the problem of inconsistent area representation in the grid representation of airspace models, which in turn leads to inconsistent flight intervals and ultimately affects flight safety.

Description

Technical Field

[0001] This invention relates to a multi-level airspace planning method, and more particularly to a multi-level airspace planning method based on a spherical rhombic discrete grid. Background Technology

[0002] Current research on airspace representation models in airspace management systems mainly focuses on isotropic grid models, while research on regular polyhedral grid models remains insufficient. The delineation of airspace grids has unique requirements regarding shape, accuracy, and encoding methods, and the four mainstream subdivision schemes each have their advantages and disadvantages. Traditional airspace management systems use isotropic grids as the representation system, but isotropic and variable latitude grids suffer from significant area deformation in high and low latitude regions, and degenerate from rectangles to triangles at the poles, failing to meet airspace representation requirements. Adaptive grids, while highly flexible, have irregular shapes, making recursive subdivision and encoding difficult and computationally challenging, thus also unsuitable for airspace representation. Summary of the Invention

[0003] Purpose of the invention: The technical problem to be solved by the present invention is to provide a multi-level spatial planning method based on a spherical rhombic discrete grid, which addresses the shortcomings of the existing technology.

[0004] To address the aforementioned technical problems, this invention discloses a multi-level spatial domain planning method based on a spherical rhombic discrete grid, comprising the following steps:

[0005] Step 1: In the airspace management system, based on the spherical latitude and longitude coordinate system and combined with the icosahedral spherical rhombic discrete grid, the airspace coordinate information is transformed from the isotropic latitude and longitude coordinate system to the spherical rectangular coordinate system. Specifically, this includes:

[0006] Step 1-1, establish the coordinate transformation function, specifically including:

[0007] Formulas for converting latitude and longitude coordinates to spherical rectangular coordinates and formulas for converting spherical rectangular coordinates to latitude and longitude coordinates are provided. The formula for converting latitude and longitude coordinates to spherical rectangular coordinates is as follows:

[0008]

[0009]

[0010]

[0011] Among them, latitude and longitude coordinates are λ is longitude. Let R be the latitude, the radius of the Earth's equator, and the corresponding spherical rectangular coordinates be C(X, Y, Z).

[0012] Except for the North and South Poles, the formulas for converting spherical rectangular coordinates to latitude and longitude coordinates are as follows:

[0013]

[0014]

[0015] When X>0 and Y>0, λ is east longitude, and λ=α.

[0016] When X < 0, Y > 0, λ is east longitude, λ = α + 90°.

[0017] When X>0 and Y<0, λ is the west longitude, and λ=α.

[0018] When X < 0, Y < 0, λ is the west longitude, λ = α + 90°.

[0019] When Z>0 North latitude,

[0020] When Z < 0 South latitude

[0021] Here, α and β are intermediate variables.

[0022] Steps 1-2, determine the coordinate point positions, i.e., the method for determining the midpoint of the rhombus grid partition is as follows:

[0023] Step 1-2-1, calculate the midpoint of the grid edge:

[0024] Let O be the center of the Earth, and R be the radius of the Earth. Points A and B are the two vertices of one side of the rhombus element, and the latitude and longitude coordinates of point A are... The spherical rectangular coordinates are (X1, Y1, Z1), and the latitude and longitude coordinates of point B are... The rectangular coordinates of the sphere are (X2, Y2, Z2); the arc M is one edge of a rhombus cell, and M is an arc. Let C be the midpoint of the line connecting points A and B. Then, by dividing the sphere by the great circle arc, we can obtain the rectangular coordinates of point C on the sphere:

[0025]

[0026] The polar coordinates of point C are obtained from trigonometric relationships:

[0027]

[0028] make:

[0029]

[0030]

[0031]

[0032] Therefore, the spherical rectangular coordinates of point M are:

[0033]

[0034] Among them, λ, r are intermediate variables;

[0035] Step 1-2-2, calculate the side length of the rhombus grid:

[0036] Points A and B are the two vertices of one side of a rhombus element, and the latitude and longitude coordinates of point A are... The latitude and longitude coordinates of point B are Then arc The length L is calculated as follows:

[0037]

[0038] in, The length L is the side length of the rhombus grid.

[0039] Step 2: Perform icosahedral rhombic mesh subdivision, specifically including:

[0040] Step 2-1: Design the icosahedral rhombic grid partitioning rules, which involves calculating and determining the partitioning levels, boundary point coordinates, and rhombic grid side lengths to obtain the scale correspondence of each grid level. Specific methods include:

[0041] The initial 10 rhombuses are at level 0. Based on the arc length of the sphere, the length of the edge of a single rhombus is approximately 7061 km. When subdivided to level 10, the length of the edge of a single rhombus is approximately 7 km. The minimum distance between non-adjacent rhombus grids is one rhombus grid interval, that is, the perpendicular distance from the rhombus vertex to the opposite side is approximately 6 km. During collision detection, the airspace is expanded by one layer, that is, by two enclosing layers, with a minimum distance of 11.94 km, which is greater than 10 km.

[0042] The resulting icosahedral rhombic lattice is divided into 10 layers.

[0043] Step 2-2, determine the grid where the coordinate point is located. Specific methods include:

[0044] Given the 3D coordinates of boundary points P1, P2, P3, and P4 of a rhombic lattice and the 3D coordinates of the point P to be determined, with the center of the sphere at point O; connect the midpoints of opposite sides of the rhombic lattice to obtain the midpoint coordinates M1, M2, M3, and M4; thus dividing the rhombic lattice into four quadrants, find the normal vector of plane OM1M3. and the normal vector of plane OM2M4 The quadrant of a point is determined based on its relationship with the plane; a quadtree partition is performed on the rhombic grid of levels 1-10, and the quadrant of the rhombic grid in which point P is located is determined by the normal vector method, thus finally determining the grid position of point P.

[0045] Step 3: Establish a global spatial coordinate coding system, perform global positioning coding on spatial coordinate points, and complete multi-level spatial planning based on a spherical rhombic discrete grid. Specific methods include:

[0046] Step 3-1: Fill the space with a space-filling curve. That is, construct multi-level Hilbert curves so that in each segmentation level of the spatial grid, the lower-level curves are formed by translating or rotating the higher-level curves according to the corresponding rules.

[0047] Connect the midpoints of opposite edges of the rhombus grid to obtain four sub-rhombuses. Let the four sub-rhombuses be the four quadrants. Fill the quadrants with Hilbert curves and set them as four states. Based on the Hilbert encoding and state transition method of the initial rhombus grid, derive the Hilbert encoding and state transition method of the sub-rhombuses.

[0048] Step 3-2 involves spatial coding of the target point, specifically including:

[0049] The encoding representation of a target point consists of the following parts:

[0050] Part 1, Diamond Code: Level 0 of the subdivision;

[0051] The second part, location code: the first to third levels of the partition; grid quadtree partitioning, with Hilbert curves used to fill the grid space, converting binary codes into Hilbert codes;

[0052] Part Three, Coordinate Code: Levels 4-10 of the partition; Grid quadtree partitioning, using Hilbert curves to fill the grid space, converting binary codes into Hilbert codes, and then converting the Hilbert codes into planar coordinates.

[0053] Step 4: In the airspace management system, manage the aircraft within the airspace under its jurisdiction according to the global positioning code described in Step 3.

[0054] Beneficial effects:

[0055] Based on practical airspace delineation, this invention leverages the ability of spherical rhombic discrete grids to minimize deformation at different latitudes in global representation, establishing a global airspace representation model based on a regular icosahedral spherical rhombic grid. The method provided by this invention effectively solves the problem of inconsistent area representation in grid representation of airspace models in traditional airspace management systems, which leads to inconsistent flight intervals and ultimately affects flight safety. Attached Figure Description

[0056] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.

[0057] Figure 1 This is a schematic diagram of the overall architecture of the present invention.

[0058] Figure 2 This is a schematic diagram of the midpoint of the grid edge in an embodiment of the present invention.

[0059] Figure 3 It is a diagram showing the relationship between the normal vector of a spatial plane and the position of a point.

[0060] Figure 4 This is the low-order Hilbert curve to high-order mapping method in the implementation examples of this invention.

[0061] Figure 5 This is a coordinate transformation diagram of an embodiment of the present invention.

[0062] Figure 6 This is a schematic diagram of the state transition modes in each quadrant of the Hilbert curve.

[0063] Figure 7 This is a schematic diagram showing the initial rhombus position numbers of a regular icosahedron. Detailed Implementation

[0064] This invention improves upon the airspace planning method in traditional airspace management systems. Traditional airspace management systems employ a grid system based on latitude and longitude coordinates. This invention discloses a multi-level airspace planning method based on a spherical rhombic discrete grid, avoiding the problem of significant deformation of latitude and longitude grids in high-latitude regions. The method includes the following steps:

[0065] Step 1: In the airspace management system, based on the spherical latitude and longitude coordinate system and combined with the regular icosahedral spherical rhombic discrete grid, realize the airspace coordinate transformation, including the coordinate transformation function and the grid midpoint calculation method;

[0066] Step 2: Method for determining the layer hierarchy scale and coordinate point location;

[0067] Step 3: Establish a global coding system for spatial coordinates, including Hilbert fill curves and coding rules;

[0068] In this invention, the coordinate transformation function mentioned in step 1 includes:

[0069] Formulas for converting latitude and longitude coordinates to spherical rectangular coordinates:

[0070]

[0071]

[0072]

[0073] Wherein, the latitude and longitude coordinates are G (longitude, latitude), the Earth's equatorial radius is R, and the corresponding spherical rectangular coordinates are C (X, Y, Z).

[0074] Formula for converting spherical rectangular coordinates to latitude and longitude coordinates:

[0075] Because trigonometric functions can exhibit a one-to-many relationship within the 0-360° range, multiple solutions may occur when converting from three-dimensional rectangular coordinates to latitude and longitude. Therefore, the specific coordinates must be determined based on the sign of the three-dimensional rectangular coordinates during the conversion. Except for the North and South Poles, the conversion relationship is as follows:

[0076]

[0077]

[0078] When X>0 and Y>0, λ is east longitude, and λ=α.

[0079] When X < 0, Y > 0, λ is east longitude, λ = α + 90°.

[0080] When X>0 and Y<0, λ is the west longitude, and λ=α.

[0081] When X < 0, Y < 0, λ is the west longitude, λ = α + 90°.

[0082] When Z>0 North latitude,

[0083] When Z < 0 South latitude

[0084] In this invention, the method for determining the midpoint of the rhombic grid partitioning described in step 1 is as follows:

[0085] 1) Calculation of the midpoint of the grid edge

[0086] like Figure 2 As shown, O is the center of the Earth, arc AB is one side of a rhombus cell, and M is an arc... The midpoint of C is The midpoint of the line connecting the points, then Therefore The coordinates of point M can then be obtained.

[0087] 2) Calculation of the side length of the rhombus grid

[0088] Given that points A and B are the two vertices of one side of a rhombus element, and the latitude and longitude coordinates of point A are... The latitude and longitude coordinates of point B are The formula for the length of arc AB is as follows:

[0089]

[0090] In this invention, step 2, obtaining the correspondence between grid scales at each level, includes:

[0091] The layer levels, boundary point coordinates, and rhombic grid side lengths were determined by calculation. The scale correspondence of each layer is shown in Table 1.

[0092] Table 1 Correspondence between different scale levels

[0093]

[0094] The initial 10 rhombuses represent level 0. Based on the spherical arc length calculation formula, the length of a single rhombus's edge is approximately 7061 km. When subdivided to level 10, the length of a single rhombus's edge is approximately 7 km. The minimum distance between non-adjacent rhombus grids is one rhombus grid interval, meaning the perpendicular distance from a rhombus vertex to its opposite edge is approximately 6 km. During collision detection, the airspace is expanded by one layer, i.e., by two enclosing layers, with a minimum distance of 11.94 km, greater than 10 km.

[0095] Therefore, subdivision up to level 10 satisfies both the minimum safe interval distance in the airspace and the grid deformation caused by different latitude regions, thus meeting the accuracy requirements for using the airspace characterization grid, and subdivision is stopped.

[0096] In this invention, the method for determining the grid location of the target point in step 2 includes:

[0097] like Figure 3 As shown, given the 3D coordinates of boundary points P1, P2, P3, and P4, and the 3D coordinates of the point P to be determined, with the center of the sphere at point O. Connect the midpoints of opposite sides of the rhombus grid to obtain the midpoint coordinates M1, M2, M3, and M4. Divide the grid into four quadrants and find the normal vector of plane OM1M3. and the normal vector of plane OM2M4 The quadrant of a point is determined based on its relationship with a plane. Let the initial Hilbert state be state 'a'. The next Hilbert state is determined based on the quadrant transition method. This hierarchical subdivision is performed sequentially up to the 10th level.

[0098] In this invention, the global positioning encoding method for spatial coordinate points described in step 3 includes:

[0099] The description of the spatial location of spatial grid cells needs to be achieved through geocoding. Hilbert curves have been proven to be the spatial filling curves that best preserve the local adjacency of spatial points. By constructing multi-level Hilbert curves, the lower-level curves in each segmentation level of the spatial grid can be formed by translating or rotating the higher-level curves according to the corresponding rules.

[0100] Connecting the midpoints of opposite edges of the rhombus grid yields four sub-rhombuses. Let these four sub-rhombuses be quadrants 0, 1, 2, and 3, respectively. Fill the quadrants with Hilbert curves, representing four states: a, b, c, and d. Figure 6 The diagram shows the state transition patterns for each quadrant of the Hilbert curve. Based on the Hilbert encoding and state transition patterns of the initial rhombus grid, the Hilbert encoding and state transition patterns of the sub-rhombuses can be derived.

[0101] The encoding rules described in step 3, i.e., the representation of the target point, consist of the following parts:

[0102] (1) First part, diamond code: the 0th level of the subdivision. Table 2 gives the latitude and longitude coordinates of the initial diamond vertices. Subsequent algorithms do not involve converting the decimal indices of the 0th level to binary, therefore decimal numbers 0-9 are used to represent the indices of the initial diamonds, facilitating quick location of the initial diamond containing the target point, such as... Figure 7 The table shows the initial rhombus position numbers of the regular icosahedron, and the latitude and longitude coordinates of the specific initial rhombus vertices are shown in Table 2.

[0103] Table 2. Latitude and longitude coordinates of the initial rhombus vertices

[0104]

[0105]

[0106] (2) Part Two, Location Code: Levels 1-3 of the partitioning. Grid quadtree partitioning, with Hilbert curves used to fill the grid space, converting binary codes into Hilbert codes;

[0107] (3) The third part, coordinate code: the 4th to 10th levels of the subdivision. The grid quadtree subdivision is performed by filling the grid space with Hilbert curves, converting the binary code into Hilbert code, and then converting the Hilbert code into (x, y) coordinates.

[0108] Finally, the improved multi-level airspace planning method based on spherical rhombic discrete grids was applied to the grid system of traditional airspace management computer software systems, which is divided by latitude and longitude grids. Ultimately, the system manages the positioning and navigation of aircraft in the airspace based on the planned airspace range, thus avoiding the problem of large deformation of the latitude and longitude grids of the airspace management system in high-latitude regions.

[0109] Example:

[0110] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0111] like Figure 1 As shown, a multi-level spatial planning method based on a spherical rhombic discrete grid is described, with the following specific steps:

[0112] Step 1: In the airspace management system, it is known that points A and B in the airspace are two vertices of one side of a rhombus cell, and the latitude and longitude coordinates of point A are... The latitude and longitude coordinates of point B are Determined by the arc length formula

[0113] like Figure 2 As shown, the midpoint of the grid edge is calculated based on latitude and longitude coordinates.

[0114] O is the center of the Earth, and the Earth's radius is R. Points A and B are the two vertices of one side of the rhombus unit, respectively. The latitude and longitude coordinates of point A are... The spherical rectangular coordinates are (X1, Y1, Z1), and the latitude and longitude coordinates of point B are... The rectangular coordinates of the sphere are (X2, Y2, Z2); the arc M is one edge of a rhombus cell, and M is an arc. Let C be the midpoint of the line connecting points A and B. Then, by dividing the sphere by the great circle arc, we can obtain the rectangular coordinates of point C on the sphere:

[0115]

[0116] The polar coordinates of point C are obtained from trigonometric relationships:

[0117]

[0118] make:

[0119]

[0120]

[0121]

[0122] Therefore, the spherical rectangular coordinates of point M are:

[0123]

[0124] Among them, λ, r are intermediate variables;

[0125] Step 2, as follows Figure 4 As shown, at level m, with the current state being 'a', when point P is located in the quadrant with the binary value 11 (i.e., sub-rhombus number 3), the state at the next level can be derived from the state transition table as 'b'. Using the binary value 11 as the code for level m, and based on this, with the current state being 'b', we continue encoding and subdividing at level m+1, obtaining the code 1111 for level m+1. As the grid space is continuously subdivided, the side length of the rhombus grid containing the target point becomes shorter and shorter until the subdivision condition is met.

[0126] Step 3, as follows Figure 5 As shown, taking latitude and longitude coordinates [117.97, 21.60] as an example, first determine that the rhombus number of the point is 1, divide the grid to the 10th level, and obtain the binary code 100011 for levels 1-3 and 11010010100110 for levels 4-10. Following the above encoding conversion, a globally unique representation of the target point is obtained, the location code: [rhombus code, location code, coordinate code].

[0127] Taking random spatial domain A as an example, given the latitude and longitude coordinates of four points in the spatial domain, the corresponding location codes are obtained after coordinate encoding using the above method, as shown in Table 3:

[0128] Table 3 Correspondence between latitude and longitude coordinates and GPS codes in airspace A

[0129]

[0130]

[0131] Ultimately, based on the aforementioned global positioning code, guidance and positioning management are provided for aircraft within the airspace under the jurisdiction of the airspace management system.

[0132] In its specific implementation, this application provides a computer storage medium and a corresponding data processing unit. The computer storage medium is capable of storing a computer program, which, when executed by the data processing unit, can run the invention's content regarding a multi-level spatial domain planning method based on a spherical rhombic discrete grid, as well as some or all of the steps in various embodiments. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc.

[0133] Those skilled in the art will clearly understand that the technical solutions in the embodiments of the present invention can be implemented using computer programs and their corresponding general-purpose hardware platforms. Based on this understanding, the technical solutions in the embodiments of the present invention, or the parts that contribute to the prior art, can be embodied in the form of computer programs, i.e., software products. These computer program software products can be stored in a storage medium and include several instructions to cause a device containing a data processing unit (which may be a personal computer, server, microcontroller, MUU, or network device, etc.) to execute the methods described in various embodiments or certain parts of the embodiments of the present invention.

[0134] This invention provides a concept and method for multi-level spatial domain planning based on a spherical rhombic discrete grid. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment of the invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technologies.

Claims

1. A multi-level spatial domain planning method based on a spherical rhombic discrete grid, characterized in that, Includes the following steps: Step 1: In the airspace management system, based on the spherical latitude and longitude coordinate system and combined with the regular icosahedral spherical rhombic discrete grid, the airspace coordinate information is converted from the latitude and longitude coordinate system to the spherical rectangular coordinate system. Step 2: Perform icosahedral rhombic mesh subdivision; Step 3: Establish a global coding system for airspace coordinates, perform global positioning coding on airspace coordinate points, and complete multi-level airspace planning based on a spherical rhombic discrete grid. Step 4: In the airspace management system, manage the aircraft within the airspace under its jurisdiction according to the global positioning code described in Step 3; Step 2, which involves dividing the icosahedral rhombic grid, specifically includes: Step 2-1: Design the partitioning rules for the icosahedral rhombic lattice; Step 2-2: Determine the grid cell containing the coordinate point; Step 2-1 describes the design of the icosahedral rhombic grid partitioning rules, which involves calculating and determining the partitioning levels, boundary point coordinates, and rhombic grid side lengths to obtain the scale correspondence of each grid level. Specific methods include: The initial 10 rhombuses are at level 0. Calculated based on the arc length of the sphere, the length of the edge of a single rhombus is 7061 km. When subdivided to level 10, the length of the edge of a single rhombus is 7 km. The minimum distance between non-adjacent rhombus grids is one rhombus grid interval, that is, the perpendicular distance from the rhombus vertex to the opposite side is 6 km. During collision detection, the airspace is expanded by one layer, that is, by two enclosing layers, with a minimum distance of 11.94 km, which is greater than 10 km. The icosahedral rhombic lattice is divided into 10 layers. The transformation of spatial coordinate information from a coordinate system of equal latitude and longitude to a spherical rectangular coordinate system described in step 1 specifically includes: Step 1-1: Establish the coordinate transformation function; Steps 1-2: Determine the coordinates of the point. The method for determining the coordinate point position, i.e., the midpoint of the rhombic grid partition, as described in steps 1-2, is as follows: Step 1-2-1, calculate the midpoint of the grid edge: Let O be the center of the Earth, and R be the radius of the Earth. Points A and B are the two vertices of one side of the rhombus element, and the latitude and longitude coordinates of point A are... The spherical rectangular coordinates are (X1, Y1, Z1), and the latitude and longitude coordinates of point B are... The rectangular coordinates of the sphere are (X2, Y2, Z2); the arc M is one edge of a rhombus cell, and M is an arc. Let C be the midpoint of the line connecting points A and B. Then, by dividing the sphere by the great circle arc, we can obtain the rectangular coordinates of point C on the sphere: The polar coordinates of point C are obtained from trigonometric relationships: make: Therefore, the spherical rectangular coordinates of point M are: Among them, λ, r are intermediate variables; Step 1-2-2, calculate the side length of the rhombus grid: Points A and B are the two vertices of one side of a rhombus element, and the latitude and longitude coordinates of point A are... The latitude and longitude coordinates of point B are Then arc The length L is calculated as follows: in, The length L is the side length of the rhombus grid.

2. The multi-level spatial domain planning method based on a spherical rhombic discrete grid according to claim 1, characterized in that, The establishment of the coordinate transformation function described in step 1-1 specifically includes: Formulas for converting latitude and longitude coordinates to spherical rectangular coordinates and formulas for converting spherical rectangular coordinates to latitude and longitude coordinates are provided. The formula for converting latitude and longitude coordinates to spherical rectangular coordinates is as follows: Among them, latitude and longitude coordinates are λ is longitude. Let R be the latitude, R be the Earth's radius, and C(X, Y, Z) be the corresponding spherical rectangular coordinates. Except for the North and South Poles, the formulas for converting spherical rectangular coordinates to latitude and longitude coordinates are as follows: When X>0 and Y>0, λ is east longitude, and λ=α. When X < 0 and Y > 0, λ is east longitude, and λ = α + 90°. When X>0 and Y<0, λ is the west longitude, and λ=α. When X < 0 and Y < 0, λ is the west longitude, and λ = α + 90°. When Z>0 North latitude, When Z < 0 South latitude Here, α and β are intermediate variables.

3. The multi-level spatial domain planning method based on a spherical rhombic discrete grid according to claim 2, characterized in that, The specific method for determining the grid where the coordinate point is located, as described in step 2-2, includes: Given the 3D coordinates of boundary points P1, P2, P3, and P4 of a rhombic lattice and the 3D coordinates of the point P to be determined, with the center of the sphere at point O; connect the midpoints of opposite sides of the rhombic lattice to obtain the midpoint coordinates M1, M2, M3, and M4; thus dividing the rhombic lattice into four quadrants, find the normal vector of plane OM1M3. and the normal vector of plane OM2M4 The quadrant of a point is determined based on its relationship with the plane; a quadtree partition is performed on the rhombic grid of levels 1-10, and the quadrant of the rhombic grid in which point P is located is determined by the normal vector method, thus finally determining the grid position of point P.

4. The multi-level spatial domain planning method based on a spherical rhombic discrete grid according to claim 3, characterized in that, Step 3, which involves performing global positioning encoding on spatial coordinate points, specifically includes the following methods: Step 3-1: Fill using a space-filling curve; Step 3-2: Perform spatial coding on the target point.

5. A multi-level spatial domain planning method based on a spherical rhombic discrete grid according to claim 4, characterized in that, The filling method described in step 3-1 is to fill the space with a space-filling curve, that is, to construct multi-level Hilbert curves so that in each segmentation level of the spatial grid, the lower-level curves are formed by the higher-level curves through translation or rotation according to the corresponding rules. Connect the midpoints of opposite edges of the rhombus grid to obtain four sub-rhombuses. Let the four sub-rhombuses be the four quadrants. Fill the quadrants with Hilbert curves and set them as four states. Based on the Hilbert encoding and state transition method of the initial rhombus grid, derive the Hilbert encoding and state transition method of the sub-rhombuses.

6. A multi-level spatial domain planning method based on a spherical rhombic discrete grid according to claim 5, characterized in that, Step 3-2, which involves spatial coding of the target point, specifically includes the following methods: The encoding representation of a target point consists of the following parts: Part 1, Diamond Code: Level 0 of the subdivision; The second part, location code: the first to third levels of the partition; grid quadtree partitioning, with Hilbert curves used to fill the grid space, converting binary codes into Hilbert codes; Part Three, Coordinate Code: Levels 4-10 of the partition; Grid quadtree partitioning, using Hilbert curves to fill the grid space, converting binary codes into Hilbert codes, and then converting the Hilbert codes into planar coordinates.

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