A low-altitude aviation navigation system adaptive projection transformation method and related device

Abstract

The application provides a low-altitude aviation navigation system adaptive projection conversion method and related device, a decision factor for projection mode switching is acquired, wherein the decision factor comprises a display scale and / or a precision main demand; a target projection mode is determined according to the decision factor; and actual geographic coordinates acquired are converted based on the target projection mode to obtain corresponding projection coordinates. The target projection mode is determined through adaptive matching according to the decision factor, so that the actual geographic coordinates acquired are converted according to the target projection mode to obtain the corresponding projection coordinates, and the requirements of precision and real-time are ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of navigation, in particular to a low-altitude aviation navigation system adaptive projection transformation method and related device. BACKGROUND

[0002] With the rapid development of low-altitude traffic, especially the increasing popularity of the use of unmanned aerial vehicles, flying cars and electric vertical take-off and landing aircraft, the traffic of aircraft in low-altitude airspace is showing a significant growth trend, giving rise to the demand for large-scale real-time flight conflict risk assessment and control in low-altitude airspace. How to ensure the accuracy and real-time requirements when performing large-scale three-dimensional flight conflict risk detection has become a difficult problem for those skilled in the art. SUMMARY

[0003] The purpose of the present application is to provide a low-altitude aviation navigation system adaptive projection transformation method and related device to improve the above problems.

[0004] To achieve the above purpose, the technical solutions adopted by the embodiments of the present application are as follows:

[0005] In a first aspect, the embodiments of the present application provide a low-altitude aviation navigation system adaptive projection transformation method, which comprises:

[0006] obtaining a decision factor for projection mode switching, wherein the decision factor includes a display scale and / or a precision main requirement;

[0007] determining a target projection mode according to the decision factor;

[0008] transforming the obtained actual geographic coordinates based on the target projection mode to obtain corresponding projection coordinates.

[0009] In a second aspect, the embodiments of the present application provide a low-altitude aviation navigation system adaptive projection transformation device, which comprises:

[0010] a first processing unit for obtaining a decision factor for projection mode switching, wherein the decision factor includes a display scale and / or a precision main requirement;

[0011] the first processing unit is further configured to determine a target projection mode according to the decision factor;

[0012] a second processing unit for transforming the obtained actual geographic coordinates based on the target projection mode to obtain corresponding projection coordinates.

[0013] In a third aspect, the embodiments of the present application provide a storage medium having a computer program stored thereon, which is executed by a processor to implement the above method.

[0014] In a fourth aspect, an electronic device is provided, and the electronic device includes a processor and a memory storing one or more programs, and the one or more programs, when executed by the processor, implement the method described above.

[0015] Compared with the prior art, the low-altitude aviation navigation system adaptive projection conversion method and the related device provided by the embodiments of the present application obtain a decision factor for projection mode switching, wherein the decision factor includes a display scale and / or a precision main demand; a target projection mode is determined according to the decision factor; and the actual geographic coordinates obtained are converted based on the target projection mode to obtain corresponding projection coordinates. The target projection mode is determined by adaptive matching according to the decision factor, so that the actual geographic coordinates obtained are converted according to the target projection mode to obtain corresponding projection coordinates, thereby guaranteeing the requirements of precision and real-time performance.

[0016] In order to make the above objectives, characteristics and advantages of the present application more apparent, clear and easy to understand, the following will specifically describe a preferred embodiment in conjunction with the accompanying drawings, and the detailed description is as follows. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments, and it should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation to the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0018] Figure 1 The structural schematic diagram of the electronic device provided by the embodiments of the present application is shown in the figure.

[0019] Figure 2 The flowchart of the low-altitude aviation navigation system adaptive projection conversion method provided by the embodiments of the present application is shown in the figure.

[0020] Figure 3 The unit schematic diagram of the low-altitude aviation navigation system adaptive projection conversion device provided by the embodiments of the present application is shown in the figure.

[0021] In the figure: 10-processor; 11-memory; 12-bus; 13-communication interface; 501-first processing unit; 502-second processing unit. DETAILED DESCRIPTION

[0022] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will be combined with the accompanying drawings for the embodiments of the present application to make a clear and complete description of the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present application.

[0024] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. Meanwhile, in the description of the present application, the terms "first", "second" and the like are only used to distinguish description, and cannot be understood as indicating or implying relative importance.

[0025] It should be noted that: similar reference numerals and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. Meanwhile, in the description of the present application, the terms "first", "second" and the like are only used to distinguish description, and cannot be understood as indicating or implying relative importance.

[0026] In the description of the present application, it should be noted that the terms "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly placed when the product of the present application is used, only for the convenience of describing the present application and simplifying the description, and cannot be understood as indicating or implying that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, therefore, cannot be understood as limiting the present application.

[0027] In the description of the present application, it is also necessary to explain that, unless otherwise explicitly specified and limited, the terms "set", "connected" should be understood broadly, for example, can be fixedly connected, can also be detachably connected, or integrally connected; can be mechanically connected, can also be electrically connected; can be directly connected, can also be indirectly connected through an intermediate medium, can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0028] Some embodiments of the present application will be described in detail below with reference to the accompanying drawings. The following examples and features in the examples can be combined with each other without conflict.

[0029] The electronic device provided by the embodiments of the present application can be a central control device of an aircraft, a ground server device or a mobile terminal device. Please refer to Figure 1 , a schematic structural diagram of the electronic device. The electronic device includes a processor 10, a memory 11 and a bus 12. The processor 10 and the memory 11 are connected through the bus 12, and the processor 10 is used to execute the executable modules stored in the memory 11, such as computer programs.

[0030] The processor 10 can be an integrated circuit chip with signal processing capability. In the implementation process, each step of the low-altitude aviation navigation system adaptive projection transformation method can be completed by the integrated logic circuit of hardware or the instruction in the form of software in the processor 10. The above-mentioned processor 10 can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP) and the like; can also be a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components.

[0031] The memory 11 can contain a high-speed random access memory (RAM), and can also include a non-volatile memory, such as at least one disk memory.

[0032] The bus 12 can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, or the like. Figure 1 Only one bidirectional arrow is shown in the figure, but it does not mean that there is only one bus 12 or only one type of bus 12.

[0033] The memory 11 is configured to store a program, for example, a program corresponding to the low-altitude aviation navigation system adaptive projection transformation device. The low-altitude aviation navigation system adaptive projection transformation device includes at least one software function module that can be stored in the memory 11 in the form of software or firmware or solidified in an operating system (OS) of the electronic device. The processor 10 executes the program to implement the low-altitude aviation navigation system adaptive projection transformation method after receiving an execution instruction.

[0034] Possibly, the electronic device provided by the embodiment of the present application further includes a communication interface 13. The communication interface 13 is connected with the processor 10 through the bus.

[0035] It should be understood that, Figure 1 The structure shown is only a schematic structure of part of the electronic device, and the electronic device can further include more or fewer components than those shown in the figure or have a different configuration from that shown in the figure. Figure 1 The components shown in the figure can be realized in hardware, software, or a combination thereof. Figure 1 Figure 1 The low-altitude aviation navigation system adaptive projection transformation method provided by the embodiment of the present application can be applied to, but is not limited to, the electronic device shown in the figure. For the specific flow, please refer to the low-altitude aviation navigation system adaptive projection transformation method.

[0036] The low-altitude aviation navigation system adaptive projection transformation method includes S10, S20, and S30, which are specifically described as follows. Figure 1 Figure 2 S10, obtaining a decision factor for projection mode switching.

[0037] The decision factor includes a display scale and / or a precision main demand.

[0038] S20, determining a target projection mode according to the decision factor.

[0039] S30, based on the target projection mode, transforming the obtained actual geographic coordinates to obtain corresponding projection coordinates.

[0040] S30, based on the target projection mode, transforming the obtained actual geographic coordinates to obtain corresponding projection coordinates.

[0041] ​​The low-altitude aviation navigation system adaptive projection conversion method provided by the embodiment of the application can adaptively match according to the decision factor to determine the target projection mode, so that the actual geographic coordinates obtained are converted according to the target projection mode to obtain corresponding projection coordinates, thereby guaranteeing the accuracy and real-time requirement.

[0042] On the basis of the foregoing, regarding the content in S20, the embodiment of the application further provides an optional implementation, please refer to the following. S20, determining the target projection mode according to the decision factor, comprising: S201 and S202, which are specifically described as follows.

[0043] S201, when the display scale is greater than the preset scale threshold, determining the Gauss projection mode as the target projection mode.

[0044] The preset scale threshold can be 1:500000.

[0045] S202, when the display scale is less than or equal to the preset scale threshold, determining the Lambert projection mode as the target projection mode.

[0046] On the basis of the foregoing, regarding the content in S20, the embodiment of the application further provides an optional implementation, please refer to the following. S20, determining the target projection mode according to the decision factor, comprising: S203 and S204, which are specifically described as follows.

[0047] S203, when the main requirement for accuracy is length accuracy (i.e., length accuracy is preferred), determining the Gauss projection mode as the target projection mode.

[0048] S204, when the main requirement for accuracy is angle accuracy (i.e., angle accuracy is preferred), determining the Lambert projection mode as the target projection mode.

[0049] When the target projection mode is the Gauss projection mode, regarding the content in S30, the embodiment of the application further provides an optional implementation, please refer to the following. S30, converting the actual geographic coordinates obtained based on the target projection mode to obtain corresponding projection coordinates, comprising: S311, S312 and S313, which are specifically described as follows.

[0050] S311, determining the dynamic central meridian according to the user center point and the set display area radius.

[0051] Optionally, the formula of the dynamic central meridian is:

[0052]

[0053] wherein, the dynamic central meridian is represented by Central meridian representing the central meridian of the region where the user center point is located, Longitude correction factor (typical value 0.0003, used to compensate for the influence of the curvature of the earth), Delta longitude representing the longitude span corresponding to a unit distance change in the plane coordinate system with the dynamic central meridian as the reference, Region longitude span, East-west direction plane coordinate after projection, Display region radius, Earth radius, Latitude of the user center point.

[0054] The central meridian in the region where the user center point is located is dynamically corrected to obtain a dynamic central meridian closer to the user center point.

[0055] S312, construct a Gauss projection plane coordinate system with the dynamic central meridian as the reference.

[0056] S313, perform Gauss projection transformation on the obtained actual geographic coordinates to obtain the corresponding projection coordinates in the Gauss projection plane coordinate system.

[0057] Optionally, the formula of Gauss projection transformation is:

[0058]

[0059] Wherein, The corresponding projection coordinates in the Gauss projection plane coordinate system, x is the east-west direction projection coordinate, y is the south-north direction projection coordinate, Actual geographic coordinates, Longitude coordinate, Latitude coordinate, Arc length distance from the equator along the central meridian to the latitude of the point to be projected, Progress difference, Dynamic central meridian (i.e. projection reference line, same as the above ), Equinoctial circle curvature radius, Eccentricity related parameter, Second eccentricity.

[0060] It should be noted that the error characteristics of Gauss projection are that the projection length ratio at the dynamic central meridian is m = 1, and the farther away from the central meridian, the greater the deformation; the maximum dimensional deformation at the edge of the 6-degree zone is 1 / 1400 (about 0.071%). The dynamic central meridian becomes a straight line (x = 0) after being "unfolded" based on the dynamic central meridian, and other meridians become curves after being projected, and the farther away from the central meridian, the greater the projection error. Based on this, the embodiment of the application also provides an implementation manner of dynamic correction, please refer to the following. S30, based on the target projection mode, the obtained actual geographic coordinates are transformed to obtain corresponding projection coordinates, and further comprising: S314, S315 and S316, which are specifically described as follows.

[0061] S314, the projection length ratio at the dynamic central meridian is obtained.

[0062] S315, when the deviation between the projection length ratio and the standard length ratio exceeds the deviation threshold, the display area radius is adjusted.

[0063] The value of the standard length ratio can be but is not limited to 1, and the value of the deviation threshold can be but is not limited to 0.0002.

[0064] S316, the dynamic central meridian is re-determined according to the user center point and the adjusted display area radius.

[0065] After S316, S312 and S313 are repeatedly executed.

[0066] Optionally, the projection length ratio m = the projection length of the target object / the actual length of the target object, that is, the projection length ratio m represents the ratio of the length after projection to the actual length.

[0067] Ideal case: m = 1 (no deformation);

[0068] Actual case: a 100-meter track is displayed as:

[0069] - m = 1.0002: display 100.02 meters (qualified);

[0070] - m = 1.0003: display 100.03 meters (out of limit, need to be adjusted).

[0071] When the deviation between the projection length ratio and the standard length ratio exceeds the deviation threshold, it indicates that the projection deformation is too large; the current central meridian is not optimized, and the coordinate system needs to be re-optimized. This error control mechanism ensures that the Gauss projection (DCG) algorithm can maintain high precision in any case, and meets the strict requirements of aviation safety.

[0072] In an optional implementation, when performing Gauss projection transformation, a 6-order Taylor expansion is adopted to improve the calculation precision.

[0073] When the longitude difference l = 3°: - 2nd order accuracy: error about ± 2.5 meters; - 4th order accuracy: error about ± 0.05 meters; - 6th order accuracy: error about ± 0.001 meters.

[0074] Regarding the content in S30, the embodiment of the application also provides an alternative implementation, please refer to the following. S30, based on the target projection mode, the actual geographic coordinates obtained are transformed to obtain corresponding projection coordinates, including: S321, S322 and S323, which are specifically described as follows.

[0075] S321, according to the user center point and the north-south span of the display area, the standard latitude is determined.

[0076] Optionally, the formula of the standard latitude is:

[0077]

[0078] Among them, the first standard latitude is represented by, the second standard latitude is represented by, the latitude of the user center point is represented by, the north-south span of the display area is represented by.

[0079] On the basis of the latitude of the user center point, dynamic correction is carried out to obtain the standard latitude closer to the latitude of the user center point.

[0080] S322, taking the standard latitude as the reference, a Lambert projection plane coordinate system is constructed.

[0081] S323, the actual geographic coordinates obtained are transformed by Lambert projection to obtain the corresponding projection coordinates in the Lambert projection plane coordinate system.

[0082] Optionally, the formula of the Lambert projection transformation is:

[0083]

[0084] Among them, the corresponding projection coordinates in the Gauss projection plane coordinate system are represented by, the actual geographic coordinates are represented by, the longitude coordinate is represented by, the latitude coordinate is represented by, the polar radius is represented by, the polar angle is represented by, the projection constant is represented by, the conic constant is represented by, the reference polar radius (the polar radius value corresponding to the origin) is represented by, Indicates the central meridian in the area where the user center point is located.

[0085] The error characteristics of Lambert projection are: no deformation at the standard latitude; the deformation is the least in the area between two standard latitudes, and the deformation at high latitude is intensified. Based on this, the embodiment of the application further provides an implementation manner of dynamic correction, please refer to the following. S30, based on the target projection mode, the obtained actual geographic coordinates are transformed to obtain corresponding projection coordinates, further comprising: S324, S325 and S326, which are specifically described as follows.

[0086] S324, the deformation amount in the target range is obtained.

[0087] Wherein, the target range is ( ).

[0088] S325, when the deformation amount exceeds the deformation threshold, the north-south span of the display area is adjusted.

[0089] Wherein, the deformation threshold is 0.05%.

[0090] S326, the standard latitude is re-determined according to the user center point and the adjusted north-south span of the display area.

[0091] After S326, S322 and S323 are repeatedly executed.

[0092] If the user center point area is in nearby, - the distance has a 10-degree gap; - the distance has a 10-degree gap; - the deformation is large at 35°N, and the angle distortion is about 0.12°.

[0093] Please refer to Figure 3 , Figure 3 A low-altitude aviation navigation system adaptive projection transformation device is provided in the embodiment of the application, and optionally, the low-altitude aviation navigation system adaptive projection transformation device is applied to the electronic device described above.

[0094] The low-altitude aviation navigation system adaptive projection transformation device comprises a first processing unit 501 and a second processing unit 502.

[0095] The first processing unit 501 is configured to obtain a decision factor for projection mode switching, wherein the decision factor comprises a display scale and / or a precision main demand.

[0096] The first processing unit 501 is further configured to determine a target projection mode according to the decision factor.

[0097] The second processing unit 502 is configured to transform the obtained actual geographic coordinates based on the target projection mode to obtain corresponding projection coordinates.

[0098] It should be noted that the low-altitude aviation navigation system adaptive projection transformation device provided in the embodiment can execute the method processes shown in the method process embodiments to achieve the corresponding technical effects. For brevity, the part not mentioned in the embodiment can be referred to the corresponding content in the above-mentioned embodiments.

[0099] The embodiment of the present application further provides a storage medium which stores computer instructions and programs, and the computer instructions and programs execute the low-altitude aviation navigation system adaptive projection transformation method of the above-mentioned embodiments when read and run. The storage medium can include memory, flash memory, register or combination thereof.

[0100] The following provides an electronic device which can be a central control device of an aircraft, a ground server device or a mobile terminal device, and the electronic device as shown in Figure 1 The electronic device can implement the low-altitude aviation navigation system adaptive projection transformation method described above. Specifically, the electronic device includes a processor 10, a memory 11 and a bus 12. The processor 10 can be a CPU. The memory 11 is used to store one or more programs, and when the one or more programs are executed by the processor 10, the low-altitude aviation navigation system adaptive projection transformation method of the above-mentioned embodiments is executed.

[0101] In summary, the low-altitude aviation navigation system adaptive projection transformation method and related device provided in the embodiment of the present application acquires a decision factor for projection mode switching, wherein the decision factor includes a display scale and / or a precision main demand; determines a target projection mode according to the decision factor; and transforms the acquired actual geographic coordinates based on the target projection mode to obtain corresponding projection coordinates. The target projection mode is determined by adaptive matching according to the decision factor, and the acquired actual geographic coordinates are transformed according to the target projection mode to obtain corresponding projection coordinates, thereby guaranteeing the requirements of precision and real-time.

[0102] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0103] It will be apparent to those skilled in the art that the application is not limited to the details of the above-exemplified embodiments and that the present application can be implemented in other particular forms without departing from the spirit or essential characteristics of the present application. The embodiments should therefore be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the above description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. No reference signs in the claims should be considered as limiting the scope of the claims with respect to the figures of the patent document.

Claims

1. An adaptive projection transformation method for a low-altitude air navigation system, characterized in that, The method includes: Obtain decision factors for projection mode switching, wherein the decision factors include display scale and / or main accuracy requirements; The target projection pattern is determined based on the decision factors; Based on the target projection mode, the acquired actual geographic coordinates are transformed to obtain the corresponding projected coordinates; When the target projection mode is Gaussian projection mode, the step of transforming the acquired actual geographic coordinates based on the target projection mode to obtain the corresponding projection coordinates includes: determining the dynamic central meridian based on the user center point and the set display area radius; constructing a Gaussian projection plane coordinate system based on the dynamic central meridian; and performing Gaussian projection transformation on the acquired actual geographic coordinates to obtain their corresponding projection coordinates in the Gaussian projection plane coordinate system. The formula for the dynamic central meridian is: in, Indicates the dynamic central meridian. This represents the central meridian within the area where the user's center point is located. This represents the longitude correction factor. This represents the change in longitude span corresponding to a unit distance change in a plane coordinate system based on the dynamic central meridian. This represents the east-west plane coordinates after projection. Indicates the radius of the display area. Represents the Earth's radius. The latitude of the user's center point; The step of transforming the acquired actual geographic coordinates based on the target projection mode to obtain the corresponding projected coordinates also includes: obtaining the projection length ratio at the dynamic central meridian; adjusting the display area radius when the deviation between the projection length ratio and the standard length ratio exceeds a deviation threshold; and redetermining the dynamic central meridian based on the user's center point and the adjusted display area radius.

2. The adaptive projection transformation method for low-altitude air navigation systems as described in claim 1, characterized in that, Determining the target projection pattern based on the decision factors includes: When the display scale is greater than a preset scale threshold, the Gaussian projection mode is determined as the target projection mode; When the display scale is less than or equal to a preset scale threshold, the Lambert projection mode is determined as the target projection mode.

3. The adaptive projection transformation method for low-altitude air navigation systems as described in claim 1, characterized in that, Determining the target projection pattern based on the decision factors includes: When the primary accuracy requirement is length accuracy, the Gaussian projection mode is determined as the target projection mode; When the primary accuracy requirement is angular accuracy, the Lambert projection mode is determined as the target projection mode.

4. The adaptive projection transformation method for low-altitude air navigation systems as described in claim 1, characterized in that, When the target projection mode is the Lambert projection mode, the step of transforming the acquired actual geographic coordinates based on the target projection mode to obtain the corresponding projected coordinates includes: Determine the standard latitude line based on the user's center point and the north-south span of the display area; A Lambert projection plane coordinate system is constructed based on the aforementioned standard parallel of latitude. The obtained actual geographic coordinates are subjected to Lambert projection transformation to obtain their corresponding projected coordinates in the Lambert projection plane coordinate system.

5. The adaptive projection transformation method for low-altitude air navigation systems as described in claim 4, characterized in that, The step of transforming the acquired actual geographic coordinates based on the target projection mode to obtain the corresponding projected coordinates also includes: Obtain the deformation within the target range; When the deformation exceeds the deformation threshold, adjust the north-south span of the display area; The standard latitude line is redefined based on the user's center point and the adjusted north-south span of the display area.

6. An adaptive projection transformation device for a low-altitude aviation navigation system, characterized in that, The device includes: The first processing unit is used to obtain decision factors for projection mode switching, wherein the decision factors include display scale and / or main accuracy requirements. The first processing unit is further configured to determine the target projection pattern based on the decision factors; The second processing unit is used to transform the acquired actual geographic coordinates based on the target projection mode to obtain the corresponding projected coordinates. When the target projection mode is Gaussian projection mode, the step of transforming the acquired actual geographic coordinates based on the target projection mode to obtain the corresponding projection coordinates includes: determining the dynamic central meridian based on the user center point and the set display area radius; constructing a Gaussian projection plane coordinate system based on the dynamic central meridian; and performing Gaussian projection transformation on the acquired actual geographic coordinates to obtain their corresponding projection coordinates in the Gaussian projection plane coordinate system. The formula for the dynamic central meridian is: in, Indicates the dynamic central meridian. This represents the central meridian within the area where the user's center point is located. This represents the longitude correction factor. This represents the change in longitude span corresponding to a unit distance change in a plane coordinate system based on the dynamic central meridian. This represents the east-west plane coordinates after projection. Indicates the radius of the display area. Represents the Earth's radius. The latitude of the user's center point; The step of transforming the acquired actual geographic coordinates based on the target projection mode to obtain the corresponding projected coordinates also includes: obtaining the projection length ratio at the dynamic central meridian; adjusting the display area radius when the deviation between the projection length ratio and the standard length ratio exceeds a deviation threshold; and redetermining the dynamic central meridian based on the user's center point and the adjusted display area radius.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the method as described in any one of claims 1-5.

8. An electronic device, characterized in that, include: Processor and memory, the memory being used to store one or more programs; When the one or more programs are executed by the processor, the method as described in any one of claims 1-5 is implemented.

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