Mercator projection method and device based on axis control engineering projection deformation

Abstract

The invention provides a Mercator projection method and device for controlling engineering projection deformation based on an axis, and relates to the technical field of engineering measurement. The method comprises the following steps: determining a latitude range of an engineering measurement area and measurement points of an engineering preset axis, wherein the measurement points comprise a south end point and a north end point of the latitude range; estimating Mercator projection length deformation of each measuring point of the project preset axis based on the latitude of each measuring point of the project preset axis; determining a target latitude with the minimum Mercator projection total length deformation of the project preset axis in the latitude range as a standard latitude; and based on the latitude of the standard latitude, carrying out Mercator projection on the project preset axis in the project measurement area. Based on the technical scheme, the projection parameters meeting the engineering projection deformation tolerance requirement can be quickly obtained for projection.

Description

Technical Field

[0001] The present disclosure relates to the technical field of engineering measurement, and in particular to a Mercator projection method and device for controlling engineering projection deformation based on an axis. Background Art

[0002] With the development of engineering surveying technology, more and more large-scale projects are being implemented, and the requirements for engineering construction are becoming higher and higher.

[0003] Usually, in order to facilitate engineering use, in the process of engineering measurement, it is necessary to project the edges on the sphere onto a developable surface, and then unfold it to determine the engineering control points for engineering layout. However, map projection will produce deformation, and Mercator projection will produce length deformation. In order to ensure the accuracy of the coordinates of the engineering control points, it is necessary to limit the degree of length deformation caused by projection. Generally, engineering measurement requires that the difference between the side length directly calculated by the control point coordinates after projection and the side length measured on the spot meet the engineering requirements. When the length deformation cannot meet the engineering requirements, some processing methods are needed to improve the length deformation of the edges in the engineering measurement area.

[0004] However, many current processing methods have high computational complexity and are time-consuming when improving length deformation. Therefore, there is an urgent need for a processing method that can quickly obtain projection parameters that meet the engineering projection deformation tolerance requirements for projection.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0006] In order to overcome the problems existing in the related art, the embodiments of the present disclosure provide a Mercator projection method and device based on axis control of engineering projection deformation, which can quickly obtain projection parameters that meet the engineering projection deformation tolerance requirements for projection.

[0007] According to a first aspect of an embodiment of the present disclosure, there is provided a Mercator projection method for controlling the deformation of an engineering projection based on an axis line, the method comprising: determining the latitude range of an engineering survey area and the measurement points of an engineering preset axis line, the measurement points comprising the south end point and the north end point of the latitude range; estimating the Mercator projection length deformation of each measurement point of the engineering preset axis line based on the latitude of each measurement point of the engineering preset axis line; determining a target latitude line with the smallest total length deformation of the Mercator projection of the engineering preset axis line within the latitude range as the standard latitude line; and performing Mercator projection on the engineering preset axis line within the engineering survey area based on the latitude of the standard latitude line.

[0008] Optionally, after estimating the Mercator projection length deformation of each measuring point based on the latitude of each measuring point of the preset axis of the project, the method further includes: estimating the total Mercator projection length deformation of the preset axis of the project based on the estimated Mercator projection length deformation of each measuring point.

[0009] Optionally, when the total number of measurement points is greater than or equal to a first threshold, the latitude is estimated based on a first preset formula: B i The first preset formula for the Mercator projection length deformation of the measurement point includes: ;in, B 0 represents the latitude of the target parallel. B i Indicates the preset axis of the project i The latitude of the measurement point.

[0010] Optionally, based on the estimated Mercator projection length deformation of each measuring point and a second preset formula, the total Mercator projection length deformation of the preset axis of the project is estimated; the second preset formula includes: ;in, B N Indicates the latitude of the northern end point of the preset axis of the project. B S Indicates the latitude of the southern end point of the project's preset axis.

[0011] Optionally, based on the estimated Mercator projection length deformation of each measuring point and a third preset formula, the total Mercator projection length deformation of the preset axis of the project is estimated; the third preset formula includes: ;in, B N Indicates the latitude of the northern end point of the preset axis of the project. B S Indicates the latitude of the southern end point of the project's preset axis.

[0012] Optionally, based on a target formula, a target latitude line within the latitude range where the total length of the Mercator projection of the preset axis of the project is deformed to zero is determined as the standard latitude line; wherein the target formula is the second preset formula or the third preset formula; the latitude of the target latitude line where the total length of the Mercator projection of the preset axis of the project is deformed to zero is .

[0013] Optionally, when the total number of measurement points is less than the first threshold, the first threshold is estimated based on a fourth preset formula. i The Mercator projection length deformation of the measurement point; the fourth preset formula includes: ; n The total number of measurement points for the preset axis of the project. Represents the measurement error; based on the estimated Mercator projection length deformation of each measurement point and the fifth preset formula, when the iteration stop condition is met, the target latitude with the smallest total length deformation of the Mercator projection of the preset axis of the project within the latitude range is determined as the standard latitude; the fifth preset formula includes: .

[0014] According to a second aspect of an embodiment of the present disclosure, a Mercator projection device for controlling the deformation of an engineering projection based on an axis line is provided, and the Mercator projection device for controlling the deformation of an engineering projection based on an axis line comprises: a measurement point determination module, a length deformation estimation module, a standard latitude determination module and a projection module; the measurement point determination module is used to determine the latitude range of an engineering measurement area and the measurement points of an engineering preset axis line; the length deformation estimation module is used to estimate the Mercator projection length deformation of each measurement point of the engineering preset axis line based on the latitude of each measurement point of the engineering preset axis line; the standard latitude determination module is used to determine the target latitude line with the smallest total length deformation of the Mercator projection of the engineering preset axis line within the latitude range as the standard latitude line; the projection module is used to perform Mercator projection on the engineering preset axis line within the engineering measurement area based on the latitude of the standard latitude line.

[0015] Optionally, the length deformation estimation module is specifically used to estimate the Mercator projection length deformation of each measuring point based on the latitude of each measuring point of the preset axis of the project, and then estimate the total Mercator projection length deformation of the preset axis of the project based on the estimated Mercator projection length deformation of each measuring point.

[0016] Optionally, the length deformation estimation module is specifically used to estimate the latitude based on a first preset formula when the total number of measurement points is greater than or equal to a first threshold value. B i The first preset formula for the Mercator projection length deformation of the measurement point includes: ;in, B 0 represents the latitude of the target parallel. B i Indicates the preset axis of the project i The latitude of the measurement point.

[0017] Optionally, the length deformation estimation module is specifically used to estimate the total length deformation of the Mercator projection of the preset axis of the project based on the estimated Mercator projection length deformation of each measuring point and a second preset formula; the second preset formula includes: ;in, B N Indicates the latitude of the northern end point of the preset axis of the project. B S Indicates the latitude of the southern end point of the project's preset axis.

[0018] Optionally, the length deformation estimation module is specifically used to estimate the total length deformation of the Mercator projection of the preset axis of the project based on the estimated Mercator projection length deformation of each measuring point and a third preset formula; the third preset formula includes: ;in, B N Indicates the latitude of the northern end point of the preset axis of the project. B S Indicates the latitude of the southern end point of the project's preset axis.

[0019] Optionally, the standard latitude determination module is specifically used to determine, based on a target formula, a target latitude within a latitude range where the total length deformation of the Mercator projection of the preset axis of the project is zero as the standard latitude; wherein the target formula is the second preset formula or the third preset formula; the latitude of the target latitude where the total length deformation of the Mercator projection of the preset axis of the project is zero is .

[0020] Optionally, the length deformation estimation module is specifically used to estimate the first i The Mercator projection length deformation of the measurement point; the fourth preset formula includes: ; n The total number of measurement points for the preset axis of the project. Represents measurement error; a standard latitude determination module, specifically used to determine the target latitude with the smallest total length deformation of the Mercator projection of the preset axis of the project within the latitude range as the standard latitude based on the estimated Mercator projection length deformation of each measurement point and the fifth preset formula when the iteration stop condition is met; the fifth preset formula includes: .

[0021] According to a third aspect of an embodiment of the present disclosure, there is provided a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the Mercator projection method based on axis control engineering projection deformation as described in the first aspect is implemented.

[0022] According to a fourth aspect of an embodiment of the present disclosure, a computer device, a memory, a processor, and computer-readable instructions stored in the memory and executable on the processor are provided, wherein the computer-readable instructions, when executed by the processor, implement the Mercator projection method based on axis control engineering projection deformation as described in the first aspect.

[0023] The technical solution provided by the embodiments of the present disclosure may have the following beneficial effects: In the disclosed embodiment, first, the latitude range of the engineering survey area is determined, and then measurement is performed based on the preset axis of the engineering within the latitude range to obtain the latitude of each measurement point, and based on the latitude of each measurement point, the Mercator projection length deformation of each measurement point of the preset axis of the engineering is estimated in advance, and the latitude with the smallest total length deformation of the Mercator projection within the latitude range is determined as the standard latitude for the final Mercator projection based on the preset axis of the engineering, and then the final Mercator projection is performed based on the standard latitude. On the one hand, since the estimation is based on the length deformation of the selected axis (i.e., the preset axis of the project), compared with the method of estimating the deformation of the projection area in the related art, the processing speed is fast and the complexity is low, which can improve the speed of determining the standard parallel; on the other hand, in the embodiment disclosed in the present invention, only the latitude of each measuring point within the latitude range is concerned, and there is no need to introduce longitude for deformation estimation. The calculation complexity is low, the accuracy is high, and it is closer to the actual deformation. The difference between the side length directly calculated based on the control point coordinates after projection and the side length obtained by field measurement can meet the engineering requirements, and the coordinates of the engineering control points can be guaranteed, which is convenient for layout in various stages of the project, so that the linear engineering penetration with high requirements for projection deformation can be more accurate and the probability of misalignment at the penetration point can be reduced.

[0024] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0026] Figure 1 A schematic diagram of the system architecture of a Mercator projection method based on axis-controlled engineering projection deformation provided in an embodiment of the present disclosure.

[0027] Figure 2 A flowchart of a Mercator projection method based on axis-controlled engineering projection deformation provided in an embodiment of the present disclosure.

[0028] Figure 3 A schematic diagram of the length deformation of a Mercator projection provided in an embodiment of the present disclosure.

[0029] Figure 4 A schematic diagram of the penetration condition of a linear project provided in an embodiment of the present disclosure.

[0030] Figure 5 A hardware structure diagram of a computer device in which a Mercator projection device for controlling engineering projection deformation based on axis lines is located according to an embodiment of the present disclosure.

[0031] Figure 6A schematic structural diagram of a Mercator projection device based on axis-controlled engineering projection deformation provided in an embodiment of the present disclosure. DETAILED DESCRIPTION

[0032] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0033] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. The singular forms of "a", "said" and "the" used in this disclosure and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0034] It should be understood that although the terms first, second, third, etc. may be used in the present disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present disclosure, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0035] Next, the embodiments of the present disclosure are described in detail.

[0036] Figure 1 A schematic diagram of the system architecture of a Mercator projection method based on axis-controlled engineering projection deformation to which an embodiment of the present disclosure can be applied is shown.

[0037] like Figure 1 As shown, the system architecture 100 may include one or more of terminal devices such as a smart phone 101, a portable computer 102, a desktop computer 103, a network 104, and a server 105. The network 104 is used to provide a medium for a communication link between the terminal device and the server 105. The network 104 may include various connection types, such as wired, wireless communication links, or optical fiber cables, etc.

[0038] The terminal device may be any electronic device with data processing function, which has a display screen for displaying to the user the latitude of the measurement point, the measured area, the projection result of the engineering preset axis based on the obtained standard latitude, etc. The electronic device includes but is not limited to the above-mentioned desktop computer, portable computer, smart phone and tablet computer, etc.

[0039] It should be understood that Figure 1 The number of terminal devices, networks and servers in the embodiment is only for illustration. Any number of terminal devices, networks and servers may be provided according to implementation requirements.

[0040] The Mercator projection method based on the projection deformation of the axis control engineering provided in the embodiment of the present disclosure can be executed by the terminal device, and accordingly, the Mercator projection device based on the projection deformation of the axis control engineering can be set in the terminal device. However, it is easy for those skilled in the art to understand that the Mercator projection method based on the projection deformation of the axis control engineering provided in the embodiment of the present disclosure can also be executed by the server 105, and accordingly, the Mercator projection device based on the projection deformation of the axis control engineering can also be set in the server 105, which is not particularly limited in this exemplary embodiment.

[0041] The disclosed embodiment limits the side length deformation by the minimum side length projection deformation condition, providing a more scientific and accurate calculation method for engineering measurement. This method is suitable for projects with high requirements for side length projection deformation, such as the connection of linear projects, such as the connection of long-distance water diversion power generation tunnels, railways, submarine tunnels, cross-sea bridges, etc., and can effectively meet engineering requirements.

[0042] like Figure 2 As shown, Figure 2 A flow chart of a Mercator projection method based on axis control engineering projection deformation provided in an embodiment of the present disclosure includes the following steps: S201. Determine the latitude range of the project survey area and the survey points of the project preset axis.

[0043] Exemplarily, the preset axis of the project can be the axis selected by the staff based on the actual project, and can be selected according to the project requirements. In the embodiment of the present disclosure, the position of the preset axis of the project can be changed, and the standard latitude can be re-determined after the change.

[0044] Optionally, the engineering preset axis may be a straight line, a broken line with at least one inflection point, or a curve, which is not specifically limited in the embodiments of the present disclosure.

[0045] It should be noted that the embodiment of the present disclosure does not specifically limit the specific selection of the preset engineering axis. It mainly estimates the Mercator projection deformation based on the selected preset engineering axis to obtain the standard latitude where the total length deformation of the Mercator projection of the preset engineering axis (also called the total projection length deformation) is the smallest.

[0046] Usually, for the penetration of some linear projects, such as long-distance water diversion and power generation tunnels, railways, undersea tunnels, cross-sea bridges, etc., the requirements for the projection deformation value of the preset axis side length of the project are relatively high. The smaller the total length deformation value of the Mercator projection of the selected axis side length, the smaller the deviation after subsequent projection, and the higher the accuracy of the penetration.

[0047] It should be noted that in actual measurement applications, the actual measurement points can be selected on the preset axis of the project or near the preset axis of the project. For example, for some inaccessible locations, the locations to the east or west of the preset axis of the project can be selected as the actual measurement points for measurement, that is, the actual measurement points may not all be on the preset axis of the project.

[0048] Among them, the measuring points include the southern end point and the northern end point of the latitude range, as well as the measuring points located on the preset axis of the project and the measuring points located near the preset axis of the project.

[0049] It should be noted that the deformation of the Mercator projection (here refers to the Orthotropic Mercator projection) is generally related to latitude but not longitude.

[0050] S202, estimating the Mercator projection length deformation of each measuring point on the preset axis of the project based on the latitude of each measuring point on the preset axis of the project.

[0051] It should be noted that in the embodiment of the present disclosure, the length deformation of the Mercator projection of each measuring point can be estimated first. The length deformation of the Mercator projection is a variable related to the selection of the standard latitude. Therefore, the determined length deformation of the Mercator projection is a deformation relationship related to the standard latitude and the latitude of the measuring point.

[0052] It should be noted that in the disclosed embodiment, the orthographic Mercator projection is used in the engineering projection. Before the projection is performed, the standard latitude with the smallest deformation of the total length of the Mercator projection is determined, that is, the projection deformation is associated with the standard latitude. Therefore, before the map projection (i.e., Mercator projection) is performed, the estimated Mercator projection length deformation of each measuring point of the preset axis of the project is a variable, which is related to the latitude of the standard latitude that needs to be determined. Based on the Mercator projection length deformation of each measuring point, the dimension of the latitude with the smallest deformation of the total length of the Mercator projection of the preset axis of the project can be determined. In the project, the standard latitude selected based on the preset axis of the project is the latitude corresponding to the latitude with the smallest deformation of the total length of the Mercator projection of the preset axis of the project.

[0053] S203, determining the target latitude line with the smallest total length deformation of the Mercator projection of the preset axis of the project within the latitude range as the standard latitude line.

[0054] Among them, the Mercator projection length deformation of each measuring point of the selected axis is the length deformation of the line segment between the measuring point and the measuring point adjacent to the measuring point projected onto the projection surface through the Mercator projection method, and the total Mercator projection length deformation of the selected axis is the length deformation of the selected axis projected onto the projection surface through the Mercator projection method.

[0055] It should be noted that two latitudes can be obtained according to calculation, one in the southern hemisphere and one in the northern hemisphere, and the latitude corresponding to the latitude within the latitude range of the preset axis of the project is determined as the target latitude.

[0056] It should be noted that when the cylindrical surface selected by the Mercator projection is tangent to the earth, there is one standard parallel with a latitude of 0°, and the projection length deformation in the rest of the latitude range is positive deformation; when the cylindrical surface selected by the Mercator projection is intersecting with the earth, there are two standard parallels, one in the southern and northern hemispheres, and the projection length deformation is negative between the standard parallels (the standard parallels indicate the area corresponding to the latitude circle) and positive outside the standard parallels. In general, the measurement area includes only one standard parallel. Taking the northern hemisphere as an example, the projection length deformation in the measurement area south of the standard parallel is negative, and the projection length deformation in the measurement area north of the standard parallel is positive.

[0057] The smaller the deformation of the estimated total length of the Mercator projection of the preset axis of the project, the more accurate the subsequent engineering calculations based on the determined standard latitude projection will be, so that the linear project can be accurately connected and the probability of staggered connection at the joint when the two ends start construction at the same time will be reduced.

[0058] S204. Based on the latitude of the standard parallel, perform Mercator projection on the preset axis of the project within the project survey area.

[0059] It should be noted that in the embodiment of the present disclosure, after estimating the standard parallel, Mercator projection within the engineering measurement area can be performed based on the standard parallel. Since the standard parallel is the parallel with the smallest deformation of the total length of the Mercator projection estimated based on the latitudes of each measuring point within the latitude range of the preset axis of the project, after obtaining the standard parallel, performing Mercator projection based on the standard parallel can make the accuracy of the linear project based on the preset axis of the project at this latitude higher during actual construction.

[0060] Figure 3 A schematic diagram of the length deformation of a Mercator projection provided by an embodiment of the present disclosure, such as Figure 3As shown in , taking the earth as a sphere as an example, the center O of the earth coincides with the center of the cylinder, where the latitude range of the preset axis of the project is [ B S , B N ]. Among them, the latitude value is B S Edge L S Projected onto the cylinder as the edge , the side length is negatively deformed; the latitude value is B i1 Edge L i1 Projected onto the cylinder as the edge , the side length is negatively deformed; the latitude value is B 0 (standard latitude) L 0 is projected onto the cylinder as an edge , the side length is not deformed; the latitude value is B i2 Edge L i2 Projected onto the cylinder as the edge , the side length undergoes positive deformation; the latitude value is B N Edge L N Projected onto the cylinder as the edge , the side length undergoes positive deformation.

[0061] Figure 4 A schematic diagram of the penetration of a linear project provided by an embodiment of the present disclosure is shown. The smaller the total length deformation of the Mercator projection of the preset axis of the project is, the higher the accuracy of the penetration is. Figure 4 As shown in (a), construction is being carried out from both the south and north boundaries, and the project can be accurately penetrated at the expected penetration point. The greater the total length deformation of the Mercator projection of the preset axis of the project, the lower the accuracy of the penetration. For example, Figure 4 As shown in (b), construction was carried out simultaneously from the south boundary and the north boundary, resulting in a misalignment problem at the expected penetration point.

[0062] The disclosed embodiment provides a Mercator projection method for controlling the deformation of engineering projection based on an axis line. First, the latitude range of the engineering survey area is determined. Then, measurement is performed based on a preset engineering axis line within the latitude range to obtain the latitude of each measurement point. Based on the latitude of each measurement point, the total length deformation of the Mercator projection of the preset engineering axis line is estimated. The latitude with the smallest total length deformation is determined as the latitude of the standard latitude for the final Mercator projection based on the preset engineering axis line. Then, the final Mercator projection is performed based on the standard latitude line. On the one hand, since the estimation is based on the length deformation of the selected axis (i.e., the preset axis of the project), compared with the method of calculating the projection area deformation in the related art, the processing speed is fast and the complexity is low, which can improve the speed and efficiency of determining the standard parallel; on the other hand, in the embodiment disclosed in the present invention, only the latitude of each measuring point within the latitude range of the preset axis of the project is concerned, and there is no need to introduce longitude for deformation estimation. The complexity is low, the accuracy is high, and it is closer to the actual deformation. The difference between the side length directly calculated based on the coordinates of the control points after projection and the side length obtained by field measurement can meet the engineering requirements, and the coordinates of the engineering control points can be guaranteed, which is convenient for layout in various stages of the project, thereby making the accuracy of linear engineering with high requirements on side length projection deformation higher and reducing the probability of misalignment at the penetration point.

[0063] It should be noted that the disclosed embodiment provides three different methods for estimating the standard parallel that minimizes the total length deformation of the Mercator projection of the preset axis of the project, wherein, when enough actual measurement points can be obtained, the Mercator projection length deformation of each measurement point is first estimated, and then based on the Mercator projection length deformation of each measurement point, the total length deformation of the Mercator projection of the preset axis of the project is estimated by the method of method one. When the number of actual measurement points that can be obtained is limited, the Mercator projection length deformation of each measurement point can be estimated first in combination with the measurement error, and then the matrix composed of the Mercator projection length deformation of each measurement point is processed based on the least squares method to directly determine the total length deformation of the Mercator projection of the preset axis of the project, that is, the processing method of method two.

[0064] Method 1: Optionally, in the Mercator projection method based on axis control engineering projection deformation provided by the embodiment of the present disclosure, after the above S202, the following S205 may be further performed: S205. Based on the estimated Mercator projection length deformation of each measuring point, estimate the total Mercator projection length deformation of the preset axis of the project.

[0065] It can be understood that the more measurement points there are, the more accurate the estimation of the total length deformation of the Mercator projection will be, and the closer it will be to the actual projection deformation.

[0066] Based on this scheme, we can first estimate the Mercator projection length deformation of each measuring point (i.e., each latitude value) within the latitude range of the project axis, and then estimate the total Mercator projection length deformation of the project preset axis based on the estimated Mercator projection length deformation of each measuring point. This can accurately obtain a deformation that is closer to the actual projection, making the determined standard latitude more in line with project needs.

[0067] Specifically, in method 1, after determining the Mercator projection length deformation of each measuring point, the total length deformation of the Mercator projection of the preset axis of the project can be estimated by two processing methods, including the following first processing method (direct summation) and second processing method (single integration).

[0068] Optionally, in the Mercator projection method based on axis control engineering projection deformation provided in the embodiment of the present disclosure, the above S202 can be specifically performed by the following S202a: S202a, when the total number of measurement points is greater than or equal to the first threshold, based on the first preset formula, the latitude is estimated to be B i The Mercator projection length deformation of the measurement points.

[0069] ; Formula (1) in, B i Indicates the preset axis of the project i The latitude of the measuring point, B 0 means the latitude of the target parallel.

[0070] It should be noted that in the embodiment of the present disclosure, in order to simplify the calculation, the earth ellipsoid is regarded as a sphere, wherein: It can express the projection length ratio at each measurement point on the earth. It represents the distance from the measuring point on the standard parallel to the Mercator projection axis. Indicates latitude B i The distance of the measuring point from the Mercator projection axis, which indicates the median axis of the cylinder used in the Mercator projection, which coincides with the earth's axis.

[0071] Furthermore, in the first processing mode, the above S205 can be executed by the following S205a: S205a, based on the estimated Mercator projection length deformation of each measuring point and formula (2), estimate the total length deformation of the Mercator projection of the preset axis of the project.

[0072] ; Formula (2) in, BN Indicates the latitude of the northern end point of the preset axis of the project. B S Indicates the latitude of the southern end point of the project's preset axis.

[0073] Based on this scheme, the total length deformation of the Mercator projection of the preset axis of the project can be determined based on the sum of the Mercator projection length deformations of each measuring point. When the latitudes of a large number of actual measuring points can be obtained, the more measuring points there are, the more accurate the total length deformation of the Mercator projection of the preset axis of the project can be estimated by summing up, thereby making the subsequent estimation of the standard latitude more accurate, and the accurate standard latitude can be quickly obtained when there are a large number of measuring points.

[0074] Optionally, in the second processing manner, in the Mercator projection method based on axis control engineering projection deformation provided in the embodiment of the present disclosure, the above S205 can be specifically performed by the following S205b: S205b, based on the estimated Mercator projection length deformation of each measuring point and formula (3), estimate the total length deformation of the Mercator projection of the preset axis of the project.

[0075] ; Formula (3) Based on this scheme, when the number of measurement points within the latitude range of the preset axis of the project can be obtained sufficiently, the above-mentioned integral form can be used to quickly and accurately determine the total length deformation of the Mercator projection on the preset axis of the project based on the estimated Mercator projection length deformation of each measurement point.

[0076] After estimating the total length deformation of the Mercator projection on the preset axis of the above-mentioned project through the above two processing methods, since the error of the projection length deformation estimated based on enough measurement points is small and the accuracy is high, it can be based on the above and Estimate the latitude where the total length deformation of the Mercator projection is 0.

[0077] Optionally, in the Mercator projection method based on axis control engineering projection deformation provided in the embodiment of the present disclosure, the above S203 can be performed by the following S203a: S203a. Based on the target formula, determine the target latitude line within the latitude range where the total length deformation of the Mercator projection of the preset axis of the project is zero as the standard latitude line.

[0078] The target formula is the above formula (2) or formula (3).

[0079] Specifically, solve the equation (4) or (5) B0 can be used to estimate the target latitude where the total length deformation of the Mercator projection of the preset axis of the project is zero. The latitude of the standard latitude is determined by the following formula (6).

[0080] ; Formula (4) ; Formula (5) ; Formula (6) It can be understood that in this case, the latitude of the final target latitude is only related to the latitude range of the preset axis of the project, that is, when estimating based on this scheme, the standard latitude can be quickly obtained based on the latitude range.

[0081] Based on this scheme, if the total length deformation of the Mercator projection of the preset axis of the project is estimated based on the above two processing methods, when the number of measuring points exceeds the preset number, the target latitude line with an overall deformation of zero can be obtained (the length deformation of zero is the minimum length deformation, that is, there are positive deformation and negative deformation at the measuring points on both sides of the standard latitude line, and the sum of the overall deformation is zero). Then, the latitude of the target latitude line with a total length deformation of the Mercator projection of the preset axis of the project is zero can be quickly obtained based on the target formula.

[0082] Method 2: Optionally, in the Mercator projection method based on axis control engineering projection deformation provided by the embodiment of the present disclosure, if the actual measurement points within the latitude range (i.e., interval) of the preset engineering axis (i.e., the selected axis) that can be obtained are limited, the standard latitude can be determined based on the least squares method, that is, S202 in the above method can also include the following S202b, and further, the above S203 can also include the following S203b: S202b, when the total number of measurement points is less than the first threshold, based on formula (7), estimate the i The Mercator projection length deformation of each measurement point.

[0083] ; Formula (7) in, n The total number of measurement points for the preset axis of the project. Represents measurement error.

[0084] In the embodiment of the present disclosure, since the number of measuring points is limited and errors are inevitable in the measurement process, introducing measurement errors when estimating the deformation of each measuring point can reduce the total error caused by the limited number of total measuring points and improve the accuracy of the estimation.

[0085] It is understandable that the above For the iThe length deformation at each measuring point is a variable value. Based on the above formula, the above formula (7) can be expanded to obtain the following matrix formula (8): ; Formula (8) in, Indicates i The unit projection length deformation at each measuring point is Indicates the distance of the standard parallels from the projection axes.

[0086] S203b, based on the estimated Mercator projection length deformation of each measuring point and formula (7), when the iteration stop condition is met, the target latitude with the smallest total length deformation of the Mercator projection of the preset axis of the project within the latitude range is determined as the standard latitude.

[0087] ;Formula (9) It should be noted that the above formula (9) can be estimated based on the above expansion formula (8) and the least square method, and then the given iteration stop condition (such as the number of iterations is greater than the preset number, or the difference between the two calculations is less than the set threshold) can be used to estimate the standard latitude value that minimizes the total length deformation value of the Mercator projection within the latitude range of the preset axis of the project (in this scheme, due to the limited number of measurement points and the existence of errors, the total length deformation value of the Mercator projection may not be 0, it may be a negative value or a positive value) B 0, so that the standard latitude can be determined to facilitate the engineering preset axis Mercator projection based on the standard latitude, which can minimize the total length deformation of the Mercator projection within the latitude range and minimize the projection deformation of the selected axis side length.

[0088] Based on this scheme, in projects that require accurate penetration of linear projects such as long-distance water diversion and power generation tunnels, railways, undersea tunnels, and cross-sea bridges, if the actual number of measurement points obtained within the latitude range of the preset axis of the project is limited, the least squares iterative calculation is performed in the form of the above matrix according to the latitude that can be measured based on a limited number of measurement points. In the case of a limited number of actual measurement points, the target latitude value with the smallest overall projection length deformation value within the latitude range of the preset axis of the project can also be quickly found.

[0089] Corresponding to the embodiments of the aforementioned method, the present disclosure also provides embodiments of a Mercator projection device for controlling engineering projection deformation based on an axis line and a computer device used therein.

[0090] The embodiments of the Mercator projection device based on axis-controlled engineering projection deformation disclosed in the present invention can be applied to computer equipment, such as servers or terminal devices. The embodiments of the Mercator projection device based on axis-controlled engineering projection deformation can be implemented by software, or by hardware or a combination of software and hardware. Taking software implementation as an example, as a Mercator projection device based on axis-controlled engineering projection deformation in a logical sense, it is formed by the processor of the engineering projection in which it is located reading the corresponding computer program instructions in the non-volatile memory into the memory and running them. From the hardware level, such as Figure 5 As shown, it is a hardware structure diagram of a computer device where the Mercator projection device based on axis control engineering projection deformation is located in the embodiment of the present disclosure, except Figure 5 In addition to the processor 510, memory 530, network interface 520, and non-volatile memory 540 shown, the server or electronic device where the Mercator projection method based on axis control engineering projection deformation is located in the embodiment may also include other hardware, usually according to the actual function of the computer device, which will not be described in detail.

[0091] like Figure 6 As shown, Figure 6 A schematic diagram of the structure of a Mercator projection device for controlling the projection deformation of an engineering project based on an axis line is provided in an embodiment of the present disclosure. The Mercator projection device 600 for controlling the projection deformation of an engineering project based on an axis line includes: a measurement point determination module 601, a length deformation estimation module 602, a standard latitude determination module 603 and a projection module 604; the measurement point determination module 601 is used to determine the latitude range of the engineering measurement area and the measurement points of the preset engineering axis line; the length deformation estimation module 602 is used to estimate the Mercator projection length deformation of each measurement point of the preset engineering axis line based on the latitude of each measurement point of the preset engineering axis line; the standard latitude determination module 603 is used to determine the target latitude line with the smallest total length deformation of the Mercator projection of the preset engineering axis line within the latitude range as the standard latitude line; the projection module 604 is used to perform Mercator projection on the preset engineering axis line in the engineering measurement area based on the latitude of the standard latitude line.

[0092] Optionally, the length deformation estimation module 602 is specifically used to estimate the Mercator projection length deformation of the preset axis of the project based on the latitude of each measuring point, and then estimate the Mercator projection length deformation of each measuring point based on the estimated Mercator projection length deformation of the preset axis of the project.

[0093] Optionally, the length deformation estimation module 602 is specifically configured to estimate the latitude as: B i The first preset formula for the Mercator projection length deformation of the measurement point includes: ;in, B 0 represents the latitude of the target parallel. B i Indicates the preset axis of the project i The latitude of the measurement point.

[0094] Optionally, the length deformation estimation module 602 is specifically used to estimate the total length deformation of the Mercator projection of the preset axis of the project based on the estimated Mercator projection length deformation of each measuring point and a second preset formula; the second preset formula includes: ;in, B N Indicates the latitude of the northern end point of the preset axis of the project. B S Indicates the latitude of the southern end point of the project's preset axis.

[0095] Optionally, the length deformation estimation module 602 is specifically used to estimate the total length deformation of the Mercator projection of the preset axis of the project based on the estimated Mercator projection length deformation of each measuring point and a third preset formula; the third preset formula includes: ;in, B N Indicates the latitude of the northern end point of the preset axis of the project. B S Indicates the latitude of the southern end point of the project's preset axis.

[0096] Optionally, the standard latitude determination module 603 is specifically used to determine, based on a target formula, a target latitude within a latitude range where the total length deformation of the Mercator projection of the preset axis of the project is zero as the standard latitude; wherein the target formula is the second preset formula or the third preset formula; the latitude of the target latitude where the total length deformation of the Mercator projection of the preset axis of the project is zero is .

[0097] Optionally, the length deformation estimation module 602 is specifically configured to estimate the first measured point based on a fourth preset formula when the total number of measured points is less than a first threshold. i The Mercator projection length deformation of the measurement point; the fourth preset formula includes: ; n The total number of measurement points for the preset axis of the project. Indicates measurement error; standard latitude determination module 603, specifically used to determine the target latitude with the smallest total length deformation of the Mercator projection of the preset axis of the project within the latitude range as the standard latitude based on the estimated Mercator projection length deformation of each measurement point and the fifth preset formula when the iteration stop condition is met; the fifth preset formula includes: .

[0098] The Mercator projection device based on axis line control of engineering projection deformation provided by the embodiment of the present disclosure first determines the latitude range of the engineering measurement area, and then performs measurement based on the preset axis line of the engineering within the latitude range to obtain the latitude of each measurement point; then, the Mercator projection device based on axis line control of engineering projection deformation estimates in advance the total length deformation of the Mercator projection of the preset axis line of the engineering based on the latitude of each measurement point, and determines the latitude with the smallest total length deformation of the Mercator projection within the latitude range as the standard latitude for the final Mercator projection based on the preset axis line of the engineering; finally, the Mercator projection device based on axis line control of engineering projection deformation performs the final Mercator projection based on the standard latitude. On the one hand, since the estimation is based on the length deformation of the selected axis (i.e., the preset axis of the project), compared with the method of estimating the deformation of the projection area in the related art, the processing speed is fast and the complexity is low, which can improve the speed of determining the standard parallel; on the other hand, in the embodiment disclosed in the present invention, only the latitude of each measuring point within the latitude range is concerned, and there is no need to introduce longitude for deformation estimation. The calculation complexity is low, the accuracy is high, and it is closer to the actual deformation. The difference between the side length directly calculated based on the control point coordinates after projection and the side length obtained by field measurement can meet the engineering requirements, and the coordinates of the engineering control points can be guaranteed, which is convenient for layout in various stages of the project, so that the linear engineering penetration with high requirements for projection deformation can be more accurate and the probability of misalignment at the penetration point can be reduced.

[0099] Correspondingly, the present disclosure also provides a Mercator projection device for controlling the deformation of engineering projection based on an axis line, and the Mercator projection device for controlling the deformation of engineering projection based on an axis line includes a processor; a memory for storing instructions executable by the processor; wherein the processor is configured to: determine the latitude range of the engineering survey area and the measurement points of the engineering preset axis line; based on the latitude of each measurement point of the engineering preset axis line, estimate the Mercator projection length deformation of each measurement point of the engineering preset axis line; determine the target latitude line with the smallest total length deformation of the Mercator projection of the engineering preset axis line within the latitude range as the standard latitude line; based on the latitude of the standard latitude line, perform Mercator projection on the engineering preset axis line within the engineering survey area.

[0100] The present disclosure also provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the computer program implements the various steps in the above-mentioned Mercator projection method embodiment based on axis control engineering projection deformation.

[0101] The present disclosure also provides a computer device, which includes a memory, a processor, and computer-readable instructions stored in the memory and executable on the processor, wherein the computer-readable instructions, when executed by the processor, implement the various steps in the above-mentioned Mercator projection method embodiment based on axis control engineering projection deformation.

[0102] The implementation process of the functions and effects of each module in the above-mentioned device is specifically described in the implementation process of the corresponding steps in the above-mentioned method, which will not be repeated here.

[0103] For the device embodiment, since it basically corresponds to the method embodiment, the relevant parts can refer to the partial description of the method embodiment. The device embodiment described above is only schematic, wherein the modules described as separate components may or may not be physically separated, and the components displayed as modules may or may not be physical modules, that is, they may be located in one place, or they may be distributed on multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the disclosed solution. A person of ordinary skill in the art can understand and implement it without paying creative labor.

[0104] The above describes specific embodiments of the present disclosure. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the embodiments and still achieve the desired results. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0105] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the inventions claimed herein. The present disclosure is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not claimed in the present disclosure. The description and examples are to be considered exemplary only, and the true scope and spirit of the present disclosure are indicated by the following claims.

[0106] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

[0107] The above description is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the scope of protection of the present disclosure.

Claims

1. A Mercator projection method based on axis control engineering projection deformation, characterized in that: The method comprises: Determine the latitude range of the project survey area and the survey points of the project preset axis; Based on the latitude of each measuring point of the preset axis of the project, estimating the Mercator projection length deformation of each measuring point of the preset axis of the project; Determine the target latitude line with the smallest total length deformation of the Mercator projection of the preset axis of the project within the latitude range as the standard latitude line; Based on the latitude of the standard parallel, a Mercator projection is performed on the preset axis of the project within the project survey area.

2. The method according to claim 1, characterized in that After estimating the Mercator projection length deformation of each measuring point based on the latitude of each measuring point of the preset axis of the project, the method further includes: Based on the estimated Mercator projection length deformation of each measuring point, the total Mercator projection length deformation of the preset axis of the project is estimated.

3. The method according to claim 2, characterized in that The estimating the Mercator projection length deformation of each measuring point based on the latitude of each measuring point of the preset axis of the project includes: When the total number of measurement points is greater than or equal to the first threshold, based on the first preset formula, the estimated latitude is B i The first preset formula for the Mercator projection length deformation of the measurement point includes: ; in, B 0 represents the latitude of the target latitude, B i The first axis of the project is indicated i The latitude of the measurement point.

4. The method according to claim 3, characterized in that The estimating the total length deformation of the Mercator projection of the preset axis of the project based on the estimated Mercator projection length deformation of each measuring point includes: Based on the estimated Mercator projection length deformation of each measuring point and a second preset formula, the total Mercator projection length deformation of the preset axis of the project is estimated; the second preset formula includes: ; in, B N Indicates the latitude of the northern end point of the preset axis of the project, B S Indicates the latitude of the southern end point of the preset axis of the project.

5. The method according to claim 3, characterized in that: The estimating the total length deformation of the Mercator projection of the preset axis of the project based on the estimated Mercator projection length deformation of each measuring point includes: Based on the estimated Mercator projection length deformation of each measuring point and a third preset formula, the total Mercator projection length deformation of the preset axis of the project is estimated; the third preset formula includes: ; in, B N Indicates the latitude of the northern end point of the preset axis of the project, B S Indicates the latitude of the southern end point of the preset axis of the project.

6. The method according to claim 4 or 5, characterized in that: The step of determining the target latitude line with the smallest total length deformation of the Mercator projection of the preset axis of the project within the latitude range as the standard latitude line comprises: Based on the target formula, determine the target latitude line where the total length deformation of the Mercator projection of the preset axis of the project within the latitude range is zero as the standard latitude line; The target formula is the second preset formula or the third preset formula; the latitude of the target latitude line where the total length deformation of the Mercator projection of the preset axis of the project is zero is .

7. The method according to claim 1, characterized in that The estimating the total length deformation of the Mercator projection of the preset axis of the project based on the latitude of each measurement point of the preset axis of the project includes: When the total number of measurement points is less than the first threshold, the fourth preset formula is used to estimate the i The Mercator projection length deformation of the measurement point; the fourth preset formula includes: ; n The total number of measurement points for the preset axis of the project, represents the measurement error; The step of determining the target latitude line with the smallest total length deformation of the Mercator projection of the preset axis of the project within the latitude range as the standard latitude line comprises: Based on the estimated Mercator projection length deformation of each measuring point and the fifth preset formula, when the iteration stop condition is met, the target latitude with the smallest total length deformation of the Mercator projection of the preset axis of the project within the latitude range is determined as the standard latitude; the fifth preset formula includes: .

8. A Mercator projection device based on axis control engineering projection deformation, characterized in that: The Mercator projection device based on axis control engineering projection deformation comprises: a measurement point determination module, a length deformation estimation module, a standard latitude determination module and a projection module; The measuring point determination module is used to determine the latitude range of the engineering measurement area and the measuring points of the preset axis of the engineering; The length deformation estimation module is used to estimate the Mercator projection length deformation of each measurement point of the preset engineering axis based on the latitude of each measurement point of the preset engineering axis; The standard latitude determination module is used to determine the target latitude with the smallest total length deformation of the Mercator projection of the preset axis of the project within the latitude range as the standard latitude; The projection module is used to perform Mercator projection on the preset axis of the project within the project survey area based on the latitude of the standard parallel.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the Mercator projection method based on axis control engineering projection deformation as described in any one of claims 1 to 7 is implemented.

10. A computer device, characterized in that: The computer device includes a memory, a processor, and computer-readable instructions stored in the memory and executable on the processor, wherein the computer-readable instructions, when executed by the processor, implement the Mercator projection method based on axis-controlled engineering projection deformation as described in any one of claims 1 to 7.

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