Method for correcting surveying and mapping data error of unmanned aerial vehicle

Abstract

The invention belongs to the technical field of unmanned aerial vehicle surveying and mapping, and discloses an unmanned aerial vehicle surveying and mapping data error correction method, which comprises the following steps: setting a plurality of parallel routes and crossing routes for a predicted surveying and mapping area; obtaining an error degree of an overlapping region of the crossing route and the parallel route and an error degree mean value of a non-overlapping region, and calculating a regional difference coefficient of the crossing route and the parallel route; based on the regional difference coefficient, calculating a view angle contribution degree set by passing through the route, and combining the obtained flight directions of all parallel routes in the to-be-mapped region and the flight direction of passing through the route to calculate the view angle environment influence performance set by passing through the route so as to correct the weight of the mapping data correction process; and introducing adjustment by taking a route intersection point of the framework as elevation control, establishing an error equation of adjustment of a block, and correcting an unmanned aerial vehicle surveying and mapping data error by introducing a weight matrix formed by correcting process weights of the corrected surveying and mapping data.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of surveying and mapping, in particular to a method for correcting errors in unmanned aerial vehicle (UAV) surveying and mapping data. BACKGROUND

[0002] Currently, the main sources of error in UAV surveying and mapping include positioning errors, image capture errors, data processing errors, and environmental factors. To reduce these errors, existing technologies use global navigation satellite systems (GNSS), differential GPS (DGPS), and real-time kinematic positioning (RTK) to improve positioning accuracy, and ground control points (GCPs) are set up in the surveying and mapping area to enable post-correction. In addition, by setting reasonable flight heights and image overlap, using high-performance gimbals and image stabilization algorithms, image capture errors can be effectively reduced. In terms of data processing, professional image processing software and optical multi-view reconstruction techniques are used to improve the accuracy of three-dimensional reconstruction. Meteorological monitoring and multi-spectral sensors can reduce the impact of environmental factors on data quality. Error models and external validation data are used for post-correction to ensure the accuracy and reliability of the surveying and mapping results.

[0003] However, the UAV surveying and mapping process is significantly affected by real-time environmental factors, including UAV parameter settings and actual environmental factors during data extraction, which can cause fluctuations in the flight position of the UAV in the flight area, further increasing the error of the surveying and mapping data. By analyzing the data connection status of parallel flight lines and crossing flight lines through flight path planning, the accuracy of error analysis caused by differences in position and light measurement during the surveying and mapping process is improved, thereby achieving correction of UAV surveying and mapping data errors, systematically eliminating cumulative errors caused by positioning, attitude, and environmental factors, and being suitable for scenarios requiring centimeter-level accuracy such as topographic mapping and emergency monitoring. SUMMARY

[0004] To overcome the deficiencies and shortcomings of the prior art, a method for correcting errors in UAV surveying and mapping data is provided.

[0005] To solve the above technical problems, the technical solution adopted by the present application is as follows: A method for correcting errors in UAV surveying and mapping data, the method comprising the following steps: Setting multiple parallel flight lines and crossing flight lines for the intended surveying and mapping area; Obtaining the error degree of the overlapping area of the crossing flight lines and the parallel flight lines and the average error degree of the non-overlapping area, and calculating the area difference coefficient of the crossing flight lines and the parallel flight lines; According to the area difference coefficient of the crossing flight lines and the parallel flight lines, the contribution degree of the viewing angle of the crossing flight lines is calculated; Obtaining the flight direction of all parallel flight lines in the area to be surveyed and the flight direction crossing the flight lines; combining the visual angle contribution degree set by the crossing flight lines, the visual angle environment influence performance set by the crossing flight lines is calculated; The visual angle environment influence performance set by the crossing flight lines is used to correct the survey data correction process weight; The intersection of the flight lines of the framework is introduced as the height control into the adjustment, the error equation of the adjustment of the regional network is established, and the weight matrix composed of the corrected survey data correction process weight is introduced to realize the correction of the error of the unmanned aerial vehicle survey data.

[0006] Preferably, before setting a plurality of parallel flight lines and crossing flight lines for the predicted survey area, it further comprises: Based on the existing map information, the survey area boundary is demarcated, and a safety buffer distance is preset; The flight height is inversely calculated according to the mapping scale requirement; The heading overlap rate is set; The side overlap rate is set.

[0007] Preferably, the error degree of the overlapping area of the crossing flight line and the parallel flight line and the error degree mean of the non-overlapping area are obtained, and the area difference coefficient of the crossing flight line and the parallel flight line is calculated, including: Obtaining twice survey data of the overlapping area of a certain crossing flight line and a certain parallel flight line, including all three-dimensional point cloud data; The matching of the actual spatial position is matched to obtain the distance of each three-dimensional point cloud after matching; The error degree of the overlapping area of a certain crossing flight line and a certain parallel flight line is represented by the mean value of the distance of all three-dimensional point clouds after matching; Obtaining the error degree mean of the non-overlapping area of a certain crossing flight line and a certain parallel flight line; According to the error degree of the overlapping area of a certain crossing flight line and a certain parallel flight line, and the error degree mean of the non-overlapping area, the area difference coefficient of a certain crossing flight line and a certain parallel flight line is calculated.

[0008] Further, according to the area difference coefficient of the crossing flight line and the parallel flight line, the visual angle contribution degree set by the crossing flight line is calculated, including: Obtaining the area difference coefficient of a certain crossing flight line and a certain parallel flight line; Obtaining the mean value of the area difference coefficient of a certain crossing flight line and other parallel flight lines; Obtaining the area difference coefficient of a certain crossing flight line and another parallel flight line; Obtaining the number of overlapping areas of a certain crossing flight line and other parallel flight lines; The view angle contribution degree of the crossing flight route is calculated according to the regional difference coefficient of a certain crossing flight route and different parallel flight routes, the average regional difference coefficient, and the number of overlapping regions of the certain crossing flight route and other parallel flight routes.

[0009] Preferably, the flight directions of all the parallel flight routes in the area to be surveyed and the flight direction of the crossing flight route are obtained, including: The surveying data of a single flight route is obtained, and all the three-dimensional point cloud data in the surveying data is projected onto a horizontal plane to obtain the second principal component direction of the surveying data. The obtained second principal component direction is taken as the flight direction of the surveying area, and the initial direction is taken as the flight direction of the first parallel flight route, thereby obtaining the flight directions of all the parallel flight routes in the surveying area and the flight direction of the certain crossing flight route.

[0010] Further, the view angle environmental impact performance of the crossing flight route is calculated according to the view angle contribution degree of the crossing flight route, including: The average difference between the flight directions of different parallel flight routes and the flight direction of the certain crossing flight route is calculated according to the obtained flight directions of the parallel flight routes in the surveying area and the flight direction of the certain crossing flight route. The obtained average difference is normalized using the maximum-minimum value, and the view angle environmental impact performance of the crossing flight route is calculated according to the view angle contribution degree of the crossing flight route.

[0011] Preferably, the surveying data correction process weight is corrected using the view angle environmental impact performance of the crossing flight route, including: The surveying data correction process weight before correction is obtained. The obtained view angle environmental impact performance of the crossing flight route is taken as a correction coefficient to correct the surveying data correction process weight before correction, thereby obtaining the surveying data correction process weight after correction.

[0012] Preferably, the intersection point of the framework is taken as the height control to introduce adjustment, the error equation of the adjustment of the regional network is established, and the weight matrix composed of the corrected surveying data correction process weight is introduced to realize the correction of the error of the unmanned aerial vehicle surveying data, including: The error equation of the adjustment of the regional network is established, and the error equation contains a parameter vector to be solved. In order to solve the parameter vector to be solved, the height value of the intersection point of the framework is taken as the prior control to establish a constraint equation of the constraint error equation. The weight matrix is introduced in the constraint equation, thereby solving the parameter vector to be solved, and further obtaining the error equation. According to the error equation, the error of the unmanned aerial vehicle surveying data is corrected, thereby realizing the correction of the error of the unmanned aerial vehicle surveying data.

[0013] Further, the error equation is defined by a residual vector, a design matrix, an observation vector and a parameter vector to be solved.

[0014] Still further, the constraint equation is established by a constraint matrix, a known elevation value vector and the parameter vector to be solved.

[0015] Compared with the prior art, the present application has the following beneficial effects: The present application sets multiple parallel flight lines and a crossing flight line in the expected surveying area, calculates the area difference coefficient of the crossing flight line and the parallel flight line according to the error degree of the overlapping area and the error degree average of the non-overlapping area of the crossing flight line and the parallel flight line, and then calculates the visual angle contribution degree of the crossing flight line setting, combines the flight direction of all the parallel flight lines in the area to be surveyed and the flight direction of the crossing flight line, calculates the visual angle environmental impact performance of the crossing flight line setting, and corrects the surveying data correction process weight in this way, establishes an error equation, and then introduces the weight matrix composed of the corrected surveying data correction process weight, thereby realizing the correction of the unmanned aerial vehicle surveying data error.

[0016] The visual angle contribution degree of the crossing flight line setting can reflect the directional influence of the local area distribution structure of the buildings or vegetation in the surveying environment, the calculation weight of the corresponding surveying data is adjusted according to the environmental influence, and the surveying data error can be effectively corrected. The present application can significantly improve the precision and reliability of the surveying data by analyzing the environmental factors and optimizing the flight line planning in the unmanned aerial vehicle surveying process. The present application can not only effectively correct the error caused by the flight position deviation, but also systematically eliminate the cumulative error caused by the positioning, attitude and environmental changes, so as to ensure that more accurate and consistent surveying results are obtained in high-precision demand scenarios such as topographic surveying and emergency monitoring. The present application not only enhances the reliability of the data, but also provides a more solid foundation for subsequent decision-making, and promotes the application development in the related field. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is the step flow chart of the unmanned aerial vehicle surveying data error correction method of the present application; Figure 2 is a schematic diagram of the present application for planning parallel flight lines and crossing flight lines; Figure 3 is a schematic block diagram of the computer equipment provided by the present application. DETAILED DESCRIPTION

[0018] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described, obviously, the described embodiments are a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative work belong to the scope of protection of the present application. The present application will be described in detail below with reference to the drawings and specific embodiments.

[0019] It should be understood that when used in the specification, the terms "comprise" and "contain" indicate the presence of described features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or sets thereof.

[0020] It should also be understood that the terms used in the present application specification are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the present application specification, "one", "a" and "the" are intended to include plural forms, unless the context clearly indicates otherwise.

[0021] It should be further understood that the term "and / or" used in the present application specification means one or more of the associated listed items and all possible combinations thereof, and includes these combinations.

[0022] Embodiments As Figure 1 shown, a method for correcting errors of unmanned aerial vehicle surveying data, the method comprising the following steps: Setting a plurality of parallel flight lines and crossing flight lines for a planned surveying area; Obtaining error degrees of overlapping areas of the crossing flight lines and the parallel flight lines and average error degrees of non-overlapping areas, and calculating area difference coefficients of the crossing flight lines and the parallel flight lines; According to the area difference coefficients of the crossing flight lines and the parallel flight lines, the contribution degree of the viewing angle of the crossing flight lines is calculated; Obtaining the flight directions of all the parallel flight lines in the area to be surveyed and the flight direction of the crossing flight lines; combining the contribution degree of the viewing angle of the crossing flight lines, the performance of the viewing angle environment of the crossing flight lines is calculated; Using the performance of the viewing angle environment of the crossing flight lines to correct the surveying data correction process weight; The intersection point of the framework flight lines is introduced as a height control into adjustment, an error equation of adjustment of the regional network is established, and the weight matrix composed of the corrected surveying data correction process weight is introduced, so as to correct the errors of the unmanned aerial vehicle surveying data.

[0023] The present application can reflect the directionality influence of the local area distribution structure of buildings or vegetation in the surveying environment through the perspective contribution degree of the crossing flight path, and can effectively correct the surveying data error by adjusting the calculation weight of the corresponding surveying data according to the environmental influence. The present application can significantly improve the precision and reliability of the surveying data by analyzing the environmental factors and optimizing the flight path planning in the process of unmanned aerial vehicle surveying. The present application can not only effectively correct the error caused by the flight position deviation, but also systematically eliminate the cumulative error caused by the positioning, attitude and environmental change, so as to ensure that more accurate and consistent surveying results are obtained in the high-precision demand scenarios such as topographic surveying and emergency monitoring. The present application not only enhances the reliability of the data, but also provides a more solid foundation for subsequent decision-making, and promotes the application development in the related field.

[0024] In a specific embodiment, before setting a plurality of parallel flight paths and crossing flight paths in the predicted surveying area, the following steps are further included: Based on the existing map information, the surveying area boundary is demarcated, and a safety buffer distance is preset, for example, the safety buffer distance is greater than or equal to 50 m, and the safety buffer distance can be 50 m or 60 m. The purpose of setting the safety buffer distance is to prevent the aircraft from colliding.

[0025] The flight height is inversely calculated according to the mapping scale requirement; for example, the GSD needs to be less than or equal to 4 cm for 1:500 mapping, and if the camera parameters are, for example, the physical focal length f=35 mm and the pixel width-height ratio a=4 μm, then the inversely calculated flight height H is approximately 300 m.

[0026] The heading overlap rate is set; for example, the heading overlap rate can be 70%, 75%, 80%, etc. By setting the heading overlap rate, the image pair splicing gap can be reduced.

[0027] The side overlap rate is set; for example, the side overlap rate can be 60%, 65%, or 70%. By setting the side overlap rate, the regional network distortion can be suppressed.

[0028] In this embodiment, data collection is carried out in a single surveying process of the surveying area, that is, a plurality of parallel flight paths and crossing flight paths are set according to the above flight path arrangement requirements in the single surveying process, the flight position of the unmanned aerial vehicle at different times is recorded, and a plurality of parameter type data such as the heading and speed at the flight position are recorded.

[0029] In the present application, the UAV survey data acquisition process is carried out in multiple routes to cover the survey area, so as to improve the survey accuracy. For the error of the final survey result, more is the error of the UAV parameter setting and the actual environment in the UAV survey data extraction process. These errors form the fluctuation of the UAV flight position in the flight area, and then increase the survey data error. Therefore, it is necessary to further analyze the relationship between the UAV route setting and the actual environment, so as to realize the accurate correction of the UAV survey data error.

[0030] According to the data relationship of parallel route and crossing route, it can be known that the survey content has certain influence on the route setting. For example, the original vertical flight is for all cases, but in some survey targets, it is more accurate to follow the corresponding distribution of survey results.

[0031] By analyzing the matching degree of survey data under the perspective, the perspective contribution degree, the data meaning of overlapping and non-overlapping parts and the perspective contribution condition reflected by the size of the proportion change of the two parts. When the terrain change has an impact on the perspective contribution degree, it means that the survey target has an impact. The terrain change has overall change and slight change, and the change is related to the angle.

[0032] In the present application, the setting purpose of the parallel route is to cover the to-be-surveyed area as much as possible, and the crossing route is to improve the accuracy of data alignment of the parallel route, including the splicing of the boundary and the data distortion problem of the overall area network. For the crossing route, the better the calibration result is when it is perpendicular to the parallel route. However, for the environmental factors in the actual survey area, for example, when the distribution of corresponding buildings is consistent with the direction distribution of the route perspective, the higher the information amount of the building survey information obtained by the UAV from the route path is, the higher the perspective contribution degree of the route is.

[0033] In this invention, the same processing is applied to the UAV mapping data acquired during each single flight path. The UAV mapping data acquired during a single flight path refers to multiple mapping areas set according to preset parameters such as heading overlap, with each mapping data acquisition process representing the data acquired within the corresponding mapping area during a single flight path. The mapping errors in the UAV mapping data acquired during single flight paths are primarily caused by local wind direction or other accidental factors. Therefore, the UAV mapping data acquired during a single flight path will have overlapping areas with mapping data acquired from other flight paths, especially with crossing flight paths. For the mapping areas of a single flight path, the overlapping areas consist of multiple parallel flight paths and multiple crossing flight paths. The specific number depends on the set flight plan; for example, four parallel flight paths and two crossing flight paths can be set, or six parallel flight paths and two crossing flight paths can be set, etc. A schematic diagram of multiple parallel flight paths and multiple crossing flight paths in this invention is shown below. Figure 2 As shown. Figure 2 As shown, since the distance of a parallel flight path is generally much greater than the distance that a cross-flight path can cover, there will inevitably be overlapping and non-overlapping areas within the mapping area of ​​a single flight path. The greater the difference between the overlapping and non-overlapping areas, the greater the difference in information acquisition during that cross-flight path, and the more important its significance for analyzing mapping errors. Simultaneously, the greater the contribution of its perspective to the mapping results.

[0034] In one specific embodiment, the error degree of the overlapping area between the crossing route and the parallel route and the mean error degree of the non-overlapping area are obtained, and the regional difference coefficient between the crossing route and the parallel route is calculated, including: Get the The crossing route and the first Two surveys of the overlapping area of ​​the parallel flight paths, including all the 3D point cloud data; The actual spatial location is matched to obtain the distance between each matched point in the 3D point cloud; The mean distance between points after matching all 3D point clouds represents the first point. The crossing route and the first Error degree of overlapping area of ​​parallel routes ; For the The crossing route and the first Regarding the overlapping area of ​​the parallel routes, in the first Within the survey area corresponding to the crossing route, the remaining areas can be considered as non-overlapping areas; thus, the first... The crossing route and the first Mean error of non-overlapping areas of parallel routes ; According to the The crossing route and the first Error degree of overlapping area of ​​parallel routes and the mean error of non-overlapping regions Calculate the first The crossing route and the first Regional difference coefficient of parallel routes .

[0035] In this embodiment, the regional difference coefficient The calculation formula is as follows: in, This indicates normalization processing.

[0036] The regional difference coefficient shows that as the crossing route gradually passes through multiple parallel route areas, the larger the regional difference coefficient value and the more consistent the behavior on the crossing route, the greater the significance of the surveying data obtained by the crossing route for error adjustment.

[0037] In one specific embodiment, the view contribution of the crossing route setting is calculated based on the regional difference coefficient between the crossing route and the parallel route, including: Get the The crossing route and the first Regional difference coefficient of parallel routes ; Get the Mean regional difference coefficient between the crossing route and other parallel routes ; Get the The crossing route and the first Regional difference coefficient of parallel routes ; Get the The number of overlapping areas between the crossing route and other parallel routes ; Combined with the The regional difference coefficient between the cross-line route and different parallel lines ( and ), and the mean of the regional difference coefficient , and the The number of overlapping areas between the crossing route and other parallel routes The perspective contribution of the crossing route setting was calculated. .

[0038] The following formula is provided in this embodiment for calculating the perspective contribution of the crossing route setting: wherein, the view angle contribution degree of the first th crossing route , the area difference coefficient of the first th crossing route and the first th parallel route, the average of the area difference coefficients of the first th crossing route and other parallel routes, the area difference coefficient of the first th crossing route and the first th parallel route, the number of overlapping areas of the first th crossing route and other parallel routes.

[0039] The view angle contribution degree of the crossing route setting is analyzed by the setting angle of the crossing route and the parallel route. However, in the actual unmanned aerial vehicle surveying process, the local area distribution structure of the buildings or vegetation in the actual surveying environment will obviously affect the surveying result; for example, the mutual shielding and other conditions will increase the surveying error, but the different setting view angles of the crossing route can reflect the directionality influence of the local area distribution structure of the buildings or vegetation in the surveying environment. Therefore, by adjusting the calculation weight of the corresponding surveying data according to the environmental influence, the surveying data error can be effectively corrected.

[0040] In a specific embodiment, the flight directions of all parallel routes in the to-be-surveyed area and the flight direction of the crossing route are obtained, including: Obtaining the surveying data of a single route flight, projecting all three-dimensional point cloud data in the surveying data to a horizontal plane, so as to obtain the second principal component direction; specifically, the purpose of projecting the three-dimensional point cloud data to the horizontal plane is to reduce the three-dimensional point cloud data to a two-dimensional plane, that is, to convert the three-dimensional data into two-dimensional data; then performing PCA calculation on the two-dimensional data, and sorting to obtain the second principal component (PC2) and its direction, thereby obtaining the second principal component direction.

[0041] The obtained second principal component direction is taken as the flight direction of the surveying area, and the initial direction is taken as the flight direction of the first parallel route (the most edge parallel route) as the reference, thereby obtaining the flight directions of all parallel routes in the surveying area (which can be understood as taking the flight direction of the first parallel route as the flight direction of all crossing routes), and the flight direction of a certain crossing route.

[0042] In addition, the present application also combines the view angle contribution degree of the crossing route setting to obtain the view angle environmental influence performance of the crossing route setting, including: flight direction of the acquired parallel flight route mapping area and the flight direction of the th crossing flight route , the average difference between the flight direction of different parallel flight route mapping areas and the flight direction of a certain crossing flight route is calculated; The maximum and minimum values of the average difference are screened out, and the visual angle environmental impact performance of the crossing flight route setting is calculated by combining the visual angle contribution degree of the crossing flight route setting.

[0043] The present application provides a calculation formula for calculating the visual angle environmental impact performance of the crossing flight route setting . Among them, represents the visual angle environmental impact performance of the th crossing flight route setting, represents the flight direction of the th parallel flight route mapping area, represents the flight direction of the th crossing flight route, represents the number of overlapping areas between the th crossing flight route and other parallel flight routes, represents the maximum and minimum value normalization of the average difference of the th crossing flight route by using the maximum and minimum values of the average difference in the range of all crossing flight routes, represents the visual angle contribution degree of the th crossing flight route. In the present application, , the greater the ratio of , the greater the influence of the mapping data obtained by the th crossing flight route relative to other crossing flight routes on the distribution of facilities in the environment, the stronger the specificity of the mapping information obtained by the

[0044] th crossing flight route, and the greater the weight of the corresponding error correction process. In a specific embodiment, the visual angle environmental impact performance of the crossing flight route setting is used to correct the mapping data correction process weight, including: acquiring the mapping data correction process weight before correction;

[0045] The visual angle environmental impact performance of the crossing flight route setting is used as a correction coefficient to correct the mapping data correction process weight before correction, and the mapping data correction process weight after correction is obtained. Among them, represents the mapping data correction process weight after correction; represents the weight of the surveying data correction process before correction, which is preset according to actual experience, or can be set to 1; represents the visual angle environment influence performance set by the crossing route of the framework,

[0046] In a specific embodiment, since the crossing route of the framework can function as an elevation control point, the number of control point measurements in the photograph is reduced, the continuity between the regional network models is enhanced, and the measurement precision of the aerial triangulation adjustment is improved. Therefore, when calculating the aerial triangulation adjustment, the bundle adjustment model can be used for calculation, that is, the least square method with constraints is used, and the intersection points of the routes of the framework are introduced into the adjustment as elevation controls.

[0047] Therefore, the intersection points of the routes of the framework are introduced into the adjustment as elevation controls, the error equation of the adjustment of the regional network is established, the weight matrix composed of the surveying data correction process weights after correction is introduced, the error of the unmanned aerial vehicle surveying data is corrected, and the correction includes: establishing an error equation of a regional network adjustment, wherein the error equation contains a parameter vector to be solved; In order to solve the parameter vector to be solved, the elevation values of the intersection points of the routes of the framework are used as prior controls to establish a constraint equation of the constraint error equation; The weight matrix is introduced into the constraint equation, so that the parameter vector to be solved is obtained, and then the error equation is obtained; According to the error equation, the error of the unmanned aerial vehicle surveying data is corrected, so that the error of the unmanned aerial vehicle surveying data is corrected.

[0048] The error equation is defined by a residual vector, a design matrix, an observation value vector and a parameter vector to be solved; and the design matrix contains the relationship between the image point coordinates and the object point.

[0049] Specifically, the error equation of the established regional network adjustment is as follows: In the formula, represents a residual vector (n x 1); represents a design matrix (n x t), which contains the relationship between the image point coordinates and the object point; represents a parameter vector to be solved (t x 1), which contains the exterior orientation elements and the encrypted point coordinates; represents an observation value vector (n x 1). n represents the number of rows, and t represents the number of columns.

[0050] The elevation values of the intersection points of the routes of the framework are introduced into the adjustment as elevation controls, ​​The constraint equation of the adjustment equation can be established as a prior control, and the constraint equation is established by a constraint matrix, a known height value vector and a parameter vector to be solved. In the formula, G is a constraint matrix (m x t), wherein m is a constraint number, and a kth row of G corresponds to a height constraint (such as [0, 0, 1, 0,...] selected from a coordinate); indicates a known height value vector (m x 1).

[0051] In the constraint equation, each crossing route in the area network has a plurality of route intersection points as height control points, and each row of the constraint matrix corresponds to the height control points; a weight matrix (diagonal matrix) is introduced into the constraint equation, and each element value of the diagonal matrix corresponds to a weight of a corrected surveying and mapping data correction process. Specifically, the constraint matrix is multiplied by the weight matrix to obtain an adjusted constraint matrix, and then the corresponding constraint equation is calculated to solve the parameter vector to be solved.

[0052] Therefore, according to the obtained weight of the corrected surveying and mapping data correction process, a corrected weight matrix is formed, which is used as the reliability of the unmanned aerial vehicle surveying and mapping data of the route intersection point at the position, so as to realize the introduction of the route intersection point as the height control into adjustment, reduce the influence of the surveying and mapping error on the final surveying and mapping result, and thus realize the correction process of the error of the unmanned aerial vehicle surveying and mapping data.

[0053] Please refer to Figure 3 , Figure 3 is a schematic block diagram of a computer device provided by an embodiment of the present application. The computer device 500 is a server, which can be a stand-alone server or a server cluster composed of multiple servers.

[0054] Please refer to Figure 3 , the computer device 500 includes a processor 502, a memory and a network interface 505 connected through a system bus 501, wherein the memory can include a non-volatile storage medium 503 and an internal memory 504.

[0055] The non-volatile storage medium 503 can store an operating system 5031 and a computer program 5032. When the computer program 5032 is executed, the processor 502 can execute the method for correcting the error of the unmanned aerial vehicle surveying and mapping data.

[0056] The processor 502 is used to provide computing and control capabilities to support the operation of the entire computer device 500.

[0057] The memory 504 provides an environment for running the computer program 5032 in the nonvolatile storage medium 503, and the computer program 5032, when executed by the processor 502, can make the processor 502 execute the method for correcting errors of surveying data of a UAV.

[0058] The network interface 505 is configured to perform network communication, such as providing transmission of data information, etc. Figure 3 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device 500 to which the scheme of the present application is applied. The specific computer device 500 can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0059] The processor 502 is configured to run the computer program 5032 stored in the memory to implement the method for correcting errors of surveying data of a UAV disclosed in the embodiments of the present application.

[0060] Those skilled in the art can understand that Figure 3 The embodiments of the computer device shown in the figure do not constitute a limitation on the specific structure of the computer device. In other embodiments, the computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components. For example, in some embodiments, the computer device can only include the memory and the processor, and in such embodiments, the structure and function of the memory and the processor are consistent with those of the memory 504 and the processor 502 shown in the embodiments, and will not be described here. Figure 3

[0061] It should be understood that, in the embodiments of the present application, the processor 502 can be a central processing unit (CPU), and the processor 502 can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), ready programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Among them, the general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc.

[0062] ​In another embodiment of the present application, a computer readable storage medium is provided. The computer readable storage medium can be a non-transitory computer readable storage medium. The computer readable storage medium stores a computer program, wherein the computer program is executed by a processor to implement the method for correcting errors in surveying data of a UAV disclosed by the embodiments of the present application.

[0063] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices, apparatuses and units can refer to the corresponding processes in the foregoing method embodiments, which will not be described here. Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized in electronic hardware, computer software or a combination of both. In order to clearly illustrate the interchangeability of hardware and software, the components and steps of each example have been described in a general manner in the foregoing description. Whether the functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. A person skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0064] In several embodiments provided by the present application, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely schematic, for example, the division of the units is merely a logical function division, and actual implementation can have another division manner, or units with the same function can be combined into one unit, for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interfaces, devices or units, or can be electrical, mechanical or other forms of connection.

[0065] The units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, i.e. they can be located in one place or distributed on multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiments of the present application.

[0066] In addition, each functional unit in each embodiment of the present application can be integrated into one processing unit, or each unit can exist physically, or two or more units can be integrated into one unit. The integrated unit can be realized in the form of hardware or software functional unit.

[0067] The integrated unit, if implemented in the form of a software function unit and sold or used as an independent product, can be stored in a storage medium. Based on such an understanding, the technical solutions of the present application essentially or say the part of the prior art that contributes to the present application, or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in various embodiments of the present application. The aforementioned storage medium includes a U disk, a mobile hard disk, a read-only memory (ROM), a magnetic disk or an optical disk, and various media that can store program codes.

[0068] Obviously, the above embodiments of the present application are only examples for clearly illustrating the present application, and are not intended to limit the implementation manner of the present application. Any modification, equivalent replacement, and improvement within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for correcting errors in UAV mapping data, characterized in that: The method comprises the following steps: Setting multiple parallel flight lines and crossing flight lines for the predicted mapping area; Obtaining the error degree of the overlapping area of the crossing flight line and the parallel flight line and the average error degree of the non-overlapping area, and calculating the area difference coefficient of the crossing flight line and the parallel flight line; According to the area difference coefficient of the crossing flight line and the parallel flight line, the visual angle contribution degree of the crossing flight line setting is calculated; Obtaining the flight direction of all parallel flight lines in the area to be mapped and the flight direction of the crossing flight line; combined with the visual angle contribution degree of the crossing flight line setting, the visual angle environment impact performance of the crossing flight line setting is calculated; The visual angle environment impact performance of the crossing flight line setting is used to correct the mapping data correction process weight; The intersection point of the flight line of the framework is introduced into adjustment as height control, the error equation of adjustment of the regional network is established, and the weight matrix composed of the corrected mapping data correction process weight is introduced to realize the correction of the unmanned aerial vehicle mapping data error.

2. The method of claim 1, wherein: Before setting multiple parallel flight lines and crossing flight lines for the predicted mapping area, it also includes: Based on the existing map information, the mapping area boundary is demarcated, and a safety buffer distance is preset; Reverse the flight height according to the mapping scale requirement; Set the heading overlap rate; Set the lateral overlap rate. 3.The method of claim 1, wherein: Obtaining the error degree of the overlapping area of the crossing flight line and the parallel flight line and the average error degree of the non-overlapping area, and calculating the area difference coefficient of the crossing flight line and the parallel flight line, comprising: Obtaining twice mapping data of the overlapping area of a certain crossing flight line and a certain parallel flight line, including all three-dimensional point cloud data; The actual spatial position matching is matched to obtain the distance of each three-dimensional point cloud after matching; The average distance of all three-dimensional point clouds after matching represents the error degree of the overlapping area of a certain crossing flight line and a certain parallel flight line; Obtaining the average error degree of the non-overlapping area of a certain crossing flight line and a certain parallel flight line; According to the error degree of the overlapping area of a certain crossing flight line and a certain parallel flight line and the average error degree of the non-overlapping area, the area difference coefficient of a certain crossing flight line and a certain parallel flight line is calculated.

4. The method of claim 3, wherein: According to the area difference coefficient of the crossing flight line and the parallel flight line, the visual angle contribution degree of the crossing flight line setting is calculated, comprising: Obtaining the area difference coefficient of a certain crossing flight line and a certain parallel flight line; Obtaining the average area difference coefficient of a certain crossing flight line and other parallel flight lines; Obtaining the area difference coefficient of a certain crossing flight line and another parallel flight line; Obtaining the number of overlapping areas of a certain crossing flight line and other parallel flight lines; Combined with the area difference coefficient of a certain crossing flight line and different parallel flight lines, the average area difference coefficient, and the number of overlapping areas of a certain crossing flight line and other parallel flight lines, the visual angle contribution degree of the crossing flight line setting is calculated.

5. The method of claim 1, wherein: Obtaining the flight direction of all parallel flight lines in the area to be mapped and the flight direction of the crossing flight line, comprising: Obtaining the mapping data of single flight line, projecting all three-dimensional point cloud data in the mapping data to the horizontal plane, thereby obtaining the second principal component direction of the mapping data; The obtained second principal component direction is taken as the flight direction of the survey area, and the initial direction is taken as the flight direction of the first parallel flight line, so as to obtain the flight directions of all parallel flight lines and the flight direction of a certain crossing flight line.

6. The method of claim 5, wherein: The visual angle contribution degree set by the crossing flight line is combined to calculate the visual angle environment influence performance set by the crossing flight line, including: According to the obtained flight directions of the parallel flight lines and the flight direction of a certain crossing flight line, the average difference between the flight directions of different parallel flight lines and the flight direction of a certain crossing flight line is calculated. The obtained average difference is normalized using the maximum-minimum value, and the visual angle contribution degree set by the crossing flight line is combined to calculate the visual angle environment influence performance set by the crossing flight line.

7. The method of claim 1, wherein: The visual angle environment influence performance set by the crossing flight line is used to correct the survey data correction process weight, including: The survey data correction process weight before correction is obtained. The obtained visual angle environment influence performance set by the crossing flight line is taken as a correction coefficient to correct the survey data correction process weight before correction, and the survey data correction process weight after correction is obtained.

8. The method of claim 1, wherein: The intersection of the flight lines of the framework is taken as the height control to introduce adjustment, the error equation of the adjustment of the regional network is established, the weight matrix composed of the corrected survey data correction process weight is introduced to realize the correction of the error of the unmanned aerial vehicle survey data, including: The error equation of the adjustment of the regional network is established, and the error equation contains a parameter vector to be solved. In order to solve the parameter vector to be solved, the height value of the intersection of the flight lines of the framework is taken as the prior control to establish the constraint equation of the constraint error equation. The weight matrix is introduced in the constraint equation, so as to solve the parameter vector to be solved, and then the error equation is obtained. According to the error equation, the error of the unmanned aerial vehicle survey data is corrected, so as to realize the correction of the error of the unmanned aerial vehicle survey data. 9.The method of claim 8, wherein: The error equation is defined by a residual vector, a design matrix, an observation value vector and a parameter vector to be solved; the design matrix contains the relationship between the image point coordinates and the object point. 10.The method of claim 8, wherein: The constraint equation is established by a constraint matrix, a known height value vector and a parameter vector to be solved.

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