Pipeline recess size acquisition method and device, electronic equipment and medium

Abstract

The application provides a pipeline recess size acquisition method and device, electronic equipment and medium. The method comprises the following steps: acquiring an original point cloud representing an outer surface of a composite recess pipeline by performing 3D laser scanning on the composite recess pipeline, wherein the composite recess pipeline comprises a recess area and a defect area; performing surface fitting on the original point cloud to obtain a first model; fitting a standard cylindrical surface according to the first model to obtain a second model; removing nodes corresponding to the defect area in the first model, and performing surface fitting on the remaining nodes of the first model to obtain a third model; and obtaining deformation parameters of the recess area according to the second model and the third model. The method solves the problem that the prior art cannot accurately acquire the recess parameters of the composite recess pipeline.

Description

TECHNICAL FIELD

[0001] The present application relates to pipeline indentation recognition technology, and in particular to a pipeline indentation size acquisition method and device, electronic equipment and a medium. BACKGROUND

[0002] Oil and gas are the lifelines of national energy, and the safety and reliability of oil and gas pipelines as the main body of storage and transportation are crucial. Indentation is a local plastic deformation caused by physical contact of the pipeline with other objects, ground movement, etc. At the same time, composite indentation combined with defects is common in actual working conditions, for example, during pipeline laying, due to ground movement, etc. The rock foreign matter moves, damages the outer anti-corrosion layer of the pipeline, and as the running time increases, corrosion is prone to occur at the damaged position, and finally a corrosion defect is formed. Composite indentation will not only reduce the bearing area of the pipeline and reduce the carrying capacity of the pipeline, but also increase the stress concentration at the indentation, reduce the fatigue load capacity of the pipeline, and have great harm to the service safety of the pipeline. Therefore, reasonable evaluation of the composite indentation of the pipeline has become an important task for the relevant departments of oil and gas pipelines.

[0003] In the prior art, the acquisition of the size of the pipeline indentation mainly adopts internal detection technology and grid diameter measurement method. Due to the resolution of the equipment or human factors, the error of the acquired indentation profile is large, and there is a problem that it is difficult to accurately acquire the indentation parameters of the composite indentation pipeline. SUMMARY

[0004] The present application provides a pipeline indentation size acquisition method and device, electronic equipment and a medium to solve the problem of difficulty in accurately acquiring the indentation parameters of the composite indentation pipeline.

[0005] In one aspect, the present application provides a pipeline indentation size acquisition method, comprising:

[0006] By 3D laser scanning of the composite indentation pipeline, the original point cloud representing the outer surface of the pipeline is acquired, wherein the composite indentation pipeline comprises a indentation area and a defect area; and the original point cloud is surface fitted to obtain a first model;

[0007] According to the first model, a standard cylindrical surface is fitted to obtain a second model; and the nodes corresponding to the defect area in the first model are removed, and the remaining nodes of the first model are surface fitted to obtain a third model;

[0008] According to the second model and the third model, the deformation parameters of the indentation area are obtained.

[0009] Optionally, the surface fitting of the original point cloud to obtain a first model comprises:

[0010] fitting a surface to the original point cloud based on a B-spline surface interpolation method to obtain a first surface;

[0011] a plurality of first axial sections and a plurality of first annular sections are respectively and equidistantly divided on the first surface, and the first model is obtained according to intersection points of the first surface and each of the first axial sections and the first annular sections.

[0012] Optionally, the second model is obtained by fitting a standard cylindrical surface according to the first model, and the method comprises the following steps of:

[0013] fitting a central axis of the pipeline according to the original point cloud to obtain a central axis parameter of the pipeline;

[0014] the second model is obtained by fitting a standard cylindrical surface based on a nonlinear least square method according to the central axis parameter and the first model.

[0015] Optionally, the third model is obtained by removing nodes corresponding to the defect area in the first model, and then fitting a surface to the remaining nodes in the first model, and the method comprises the following steps of:

[0016] the curvature of each node in the first model is obtained based on a point cloud curvature algorithm according to the first model;

[0017] a node with a curvature change rate exceeding a preset value is taken as a defect feature point, all the defect feature points are connected to form a defect boundary, and a region surrounded by the defect boundary is segmented and deleted, wherein the curvature change rate of the node is a change rate of the curvature of the node relative to the curvature of an adjacent node;

[0018] a second surface is obtained by fitting a surface to the remaining nodes in the first model based on a B-spline surface interpolation method;

[0019] a plurality of second axial sections and a plurality of second annular sections are respectively and equidistantly divided on the second surface, and the third model is obtained according to intersection points of the second surface and each of the second axial sections and the second annular sections, wherein the number of the second axial sections is the same as that of the first axial sections, and the number of the second annular sections is the same as that of the first axial sections.

[0020] Optionally, the deformation parameter of the recessed area is obtained according to the second model and the third model, and the method comprises the following steps of:

[0021] according to a geometric relationship, a central surface node of the pipeline corresponding to each node in the second model and the third model is obtained as an original central surface node and a recessed central surface node of the pipeline;

[0022] According to the original middle surface node and the corresponding recessed middle surface node, a radial displacement, a circumferential displacement and a deflection angle of each original middle surface node and the corresponding inner and outer wall node during a pipe recessing process are obtained as deformation parameters of the recessed area.

[0023] Optionally, the method further comprises:

[0024] An axial length of the defect boundary is obtained as a defect length of the defect area.

[0025] A circumferential length of the defect boundary is obtained as a defect width of the defect area.

[0026] A radial length of the defect boundary is obtained as a defect depth of the defect area.

[0027] Optionally, before the original point cloud is fitted to obtain the first model, the method further comprises:

[0028] The original point cloud is subjected to noise reduction and smoothing processing to remove sharp features and burrs.

[0029] In another aspect, the application provides a pipe composite recess size acquisition device, comprising:

[0030] A first modeling module is configured to acquire an original point cloud representing an outer surface of a composite recess pipe by performing 3D laser scanning on the composite recess pipe, wherein the composite recess pipe comprises a recess area and a defect area, and the original point cloud is fitted to obtain a first model.

[0031] A second modeling module is configured to fit a standard cylindrical surface according to the first model to obtain a second model, and remove nodes corresponding to the defect area in the first model, and fit a third model to the remaining nodes of the first model.

[0032] An acquisition module is configured to obtain deformation parameters of the recessed area according to the second model and the third model.

[0033] Optionally, the first modeling module is specifically configured to:

[0034] The original point cloud is fitted to obtain a first surface based on a B-spline surface interpolation method.

[0035] A plurality of first axial sections and a plurality of first circumferential sections are respectively and equidistantly divided on the first surface, and the first model is obtained according to intersection points of the first surface and each of the first axial sections and the first circumferential sections.

[0036] Optionally, the second modeling module is specifically configured to:

[0037] fitting a center axis line of the original point cloud to obtain a center axis line parameter corresponding to the pipeline;

[0038] fitting a standard cylindrical surface based on a non-linear least square method according to the center axis line parameter and the first model to obtain the second model.

[0039] Optionally, the second modeling module is further configured to:

[0040] obtaining curvatures of each node in the first model based on a point cloud curvature algorithm according to the first model;

[0041] taking a node with a curvature change rate exceeding a preset value as a defect feature point, connecting all the defect feature points to form a defect boundary, and segmenting and deleting a region surrounded by the defect boundary, wherein the curvature change rate of the node is a change rate of the curvature of the node relative to curvatures of adjacent nodes;

[0042] fitting a surface to remaining nodes in the first model based on a B-spline surface interpolation method to obtain a second surface;

[0043] dividing a plurality of second axial sections and a plurality of second circumferential sections on the second surface at equal intervals respectively, and obtaining the third model according to intersection points of the second surface and each of the second axial sections and the second circumferential sections, wherein the number of the second axial sections is the same as the number of the first axial sections, and the number of the second circumferential sections is the same as the number of the first axial sections.

[0044] Optionally, the obtaining module is configured to:

[0045] obtaining, according to geometric relationships, a center surface node of the pipeline corresponding to each node in the second model and the third model respectively as an original center surface node and a recessed center surface node of the pipeline;

[0046] obtaining, according to the original center surface node and the corresponding recessed center surface node of the pipeline, radial displacement, circumferential displacement and deflection angle of each of the original center surface nodes and the corresponding inner and outer wall nodes in a pipeline recessing process as deformation parameters of the recessed region.

[0047] Optionally, the device further comprises a second obtaining module configured to:

[0048] obtaining an axial length of the defect boundary as a defect length of the defect region;

[0049] obtaining a circumferential length of the defect boundary as a defect width of the defect region;

[0050] obtaining a radial length of the defect boundary as a defect depth of the defect region.

[0051] Optionally, the acquisition module is further configured to:

[0052] The original point cloud is subjected to noise reduction and smoothing processing to remove sharp features and burrs.

[0053] In another aspect, the present application provides an electronic device, comprising a processor and a memory connected to the processor in communication; the memory stores computer execution instructions; the processor executes the computer execution instructions stored in the memory to implement the method as described above.

[0054] In another aspect, the present application provides a computer readable storage medium, the computer readable storage medium stores computer execution instructions, the computer execution instructions are executed by a processor to implement the method as described above.

[0055] In the pipeline recess size acquisition method, device, electronic device and medium provided by the present application, the original point cloud representing the outer surface of the pipeline is obtained by 3D laser scanning of the composite recess pipeline, wherein the composite recess pipeline comprises a recess area and a defect area; the original point cloud is subjected to surface fitting to obtain a first model; a standard cylindrical surface is fitted according to the first model to obtain a second model; the nodes corresponding to the defect area in the first model are removed, and the remaining nodes of the first model are subjected to surface fitting to obtain a third model; and the deformation parameters of the recess area are obtained according to the second model and the third model. Based on the 3D laser scanning technology, the present application can accurately and quickly obtain the geometric data and topography of the composite recess pipeline, greatly avoiding errors caused by non-standard use of measuring tools by measuring personnel and vibration of the detector itself, and by establishing the second model representing the original state of the pipeline and the third model representing the recess pipeline, the influence of the corrosion area of the pipeline on the calculation of the recess deformation parameters is excluded, so that the independent recess parameters of the composite recess pipeline can be calculated and obtained, and the calculation accuracy of the recess size of the pipeline is effectively improved. BRIEF DESCRIPTION OF DRAWINGS

[0056] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0057] Figure 1 FIG. 1 exemplarily shows a flowchart of the pipeline recess size acquisition method provided by the first embodiment of the present application;

[0058] Figure 2 FIG. 2 exemplarily shows an example diagram of a pipeline model cross section provided by the first embodiment of the present application;

[0059] Figure 3Fig. 1 shows an example of a pipe model profile provided by the embodiment one of the present application;

[0060] Figure 4 Fig. 2 shows an example of the first curved surface division provided by the embodiment one of the present application;

[0061] Figure 5 Fig. 3 shows a three-dimensional example of the first model provided by the embodiment one of the present application;

[0062] Figure 6 Fig. 4 shows a side view example of the first model provided by the embodiment one of the present application;

[0063] Figure 7 Fig. 5 shows an example of the second model provided by the embodiment one of the present application;

[0064] Figure 8 Fig. 6 shows an example of the third model provided by the embodiment one of the present application;

[0065] Figure 9 Fig. 7 shows a schematic diagram of calculating the pipe recess deformation parameter provided by the embodiment one of the present application;

[0066] Figure 10 Fig. 8 shows an example of the third model in the rectangular coordinate system provided by the embodiment one of the present application;

[0067] Figure 11 Fig. 9 shows an example of the third model in the cylindrical coordinate system provided by the embodiment one of the present application;

[0068] Figure 12 Fig. 10 shows an example of the first model in the rectangular coordinate system provided by the embodiment one of the present application;

[0069] Figure 13 Fig. 11 shows a structural schematic diagram of the pipe recess size acquisition device provided by the embodiment two of the present application;

[0070] Figure 14 Fig. 12 shows a structural schematic diagram of the pipe recess size acquisition electronic device provided by the embodiment three of the present application.

[0071] The above figures have shown the specific embodiments of the present application, which will be described in more detail hereinafter. These figures and textual descriptions are not intended to limit the scope of the concept of the present application by any means, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0072] The exemplary embodiments will be described in detail herein with reference to the attached drawings. In the following description, like reference numerals refer to like elements, unless indicated otherwise. The following description of exemplary embodiments is not representative of all possible embodiments consistent with the present application. Rather, it is merely an example of apparatus and methods consistent with some aspects of the present application as detailed in the appended claims.

[0073] In recent years, with the steady growth of demand for oil and gas resources in China, the development speed of oil and gas pipeline construction has accelerated. Pipeline transportation is a relatively safe and reliable mode of transportation, but pipeline accidents occur from time to time due to manufacturing and welding defects, cracks, leaks, corrosion, and damage to the external anticorrosion layer. The failure of the pipeline not only reduces the service life of the pipeline, but also poses a serious threat to people's life and property safety.

[0074] A dent is a local plastic deformation caused by physical contact of the pipeline with other objects, ground movement, etc. It often causes local stress and strain concentration in the pipeline, which can easily lead to fatigue failure and adversely affect the integrity of the pipeline. At the same time, composite dents combining defects and dents are common in actual working conditions, such as movement of rocks and foreign objects due to ground movement during pipeline laying, which damages the external anticorrosion layer of the pipeline. As the service life increases, corrosion is prone to occur at the damaged location, eventually forming a corrosion defect. During pipeline transportation, collisions and extrusions often occur at the defect location, forming a composite defect of corrosion dent, which not only significantly reduces the carrying capacity of the pipeline, but also increases stress concentration, eventually causing pipeline failure.

[0075] The technical solutions of the present application will be described in detail below with specific examples. The following specific examples can be combined with each other, and the same or similar concepts or processes may not be described again in some examples.

[0076] Embodiment One

[0077] Figure 1 The flowchart of the pipeline dent size acquisition method provided by an embodiment of the present application is shown. As shown in Figure 1 The pipeline dent size acquisition method provided by the present embodiment can include:

[0078] S101, by 3D laser scanning on the composite dent pipeline, the original point cloud representing the outer surface of the pipeline is obtained, wherein the composite dent pipeline includes a dent area and a defect area; and the original point cloud is fitted to a curved surface to obtain a first model;

[0079] S102, fitting a standard cylindrical surface according to the first model to obtain a second model; and removing the nodes corresponding to the defect area in the first model, and performing surface fitting on the remaining nodes of the first model to obtain a third model.

[0080] S103, obtaining the deformation parameter of the recessed area according to the second model and the third model.

[0081] In practical applications, the execution subject of the embodiment can be a pipeline recess size acquisition device, which can be realized by a computer program, for example, application software, etc.; or it can also be realized as a medium storing a related computer program, for example, a U disk, a cloud disk, etc.; or it can also be realized through an entity device integrated or installed with a related computer program, for example, a chip, a server, etc.

[0082] Specifically, the pipeline containing a composite recess is subjected to 3D laser scanning, wherein the pipeline containing a composite recess includes a recessed area and a defect area, and original point cloud data of the outer surface of the pipeline is obtained. The original point cloud is subjected to surface fitting to obtain a first model for representing the curved surface structure of the outer surface of the pipeline; wherein the surface fitting can be realized in a reverse engineering software (such as Geomagic DeignX, etc.), which is not limited herein.

[0083] On the basis of the first model, a standard cylindrical surface is fitted according to the point coordinates in the first model to obtain a second model for representing the outer surface of the pipeline without a composite recess; and a third model is obtained by removing the nodes corresponding to the defect area of the pipeline in the first model according to the point coordinates in the first model, for representing the outer surface of the pipeline containing only the recessed area and not containing the defect area.

[0084] According to the second model and the third model, the recessed area of the pipeline can be demarcated, and thus the deformation parameter of the recessed area of the pipeline is obtained.

[0085] For example, Figure 2 the example diagram of the pipeline model section provided by an embodiment of the present application, Figure 3 the example diagram of the pipeline model section provided by an embodiment of the present application, and Table 1 is the pipeline parameter table provided by an embodiment of the present application, as shown in Figure 2 、 Figure 3 and Table 1, it is assumed that a pipeline containing a composite recess with a pipe material model X65 is currently desired to obtain a recess size, the pipeline is scanned using a 3D laser scanning technology, original point cloud of the outer surface of the pipeline is obtained, and surface fitting is performed to obtain a first model.

[0086] Table 1 Pipeline Parameters

[0087]

[0088] To improve data validity and reduce subsequent computational difficulty, in one example, before performing surface fitting on the original point cloud to obtain the first model, the following steps are also included:

[0089] The original point cloud is subjected to noise reduction and smoothing processing to remove sharp features and jagged edges.

[0090] Specifically, the original point cloud is denoised and smoothed to eliminate unnecessary sharp features, and excess jagged edges at both ends of the corresponding pipes are trimmed, thereby preprocessing the original point cloud data and improving data quality.

[0091] In practical applications, there can be multiple methods to obtain the first model. In one example, the method of performing surface fitting on the original point cloud to obtain the first model includes:

[0092] Based on the B-spline surface interpolation method, the original point cloud is fitted with a surface to obtain the first surface;

[0093] The first surface is divided into multiple first axial sections and multiple first circumferential sections at equal intervals. The first model is obtained based on the intersection points of the first surface with each of the first axial sections and the first circumferential sections.

[0094] Specifically, since the original point cloud data is relatively scattered, it needs to be regularized, i.e., surface fitting. Surface fitting can effectively fill the data gaps in the original point cloud. There are various methods for surface fitting. Here, B-spline surface interpolation is used to fit the original point cloud to obtain the first surface.

[0095] For data point {P i The curve S fitted using a cubic B-spline function for |i=1,2,…,n} n Connect the two lines, because the cubic B-spline function has second-order continuity, and S can be calculated directly. n The curvature at any point on the curve S. n It is composed of (n-1) curve segments, and can be controlled by (n+2) vertices {B} i The fitting accuracy is controlled by |i=0,1,…,n+1}.

[0096] Due to the presence of corrosion defects, the reconstructed surface requires high accuracy; otherwise, it will significantly affect the defect characteristic parameters. n Above it and P i The corresponding point is t i It can be calculated by accumulating the chord length:

[0097]

[0098] In the formula, {L j |j=2,3,…,n} is a point Pj-1 With P j The arc length between them.

[0099] The parameters of a surface in three-dimensional space are expressed as follows:

[0100] S(u,v)=[x(u,v),y(u,v),z(u,v)],(u,v)∈R 2

[0101] At this point, the surface is represented by two parameters, u and v, and the surface is mapped onto a uv-plane region in three-dimensional Euclidean space.

[0102] The cubic B-spline surface is represented as:

[0103]

[0104] In the formula, B i,j To control vertices, they can be connected to form a control polygon; N i,3 (u) and N j,3 (v) is a cubic B-spline basis function. According to the recursive formula proposed by de Boor and Cox, we have:

[0105]

[0106]

[0107] The first surface is obtained after surface reconstruction.

[0108] To facilitate subsequent data processing, the first surface is divided into a regularized mesh, including: dividing the first surface into n equally spaced first axial sections and p equally spaced first circumferential sections, and setting the set of intersection points {x} between the first surface and each of the first axial sections and first circumferential sections. i,j ,y i,j ,z i |i=1,2,…,n;j=1,2,…,2p}, as the first model.

[0109] Figure 4 A schematic diagram of the first surface partitioning provided in an embodiment of this application, as shown below. Figure 4 As shown, the first curved surface is divided into three first axial sections N1, N2, and N3 and two first circumferential sections P1 and P2 at equal intervals. The intersection points of the first curved surface with N1, N2, N3 and P1, P2 are obtained, respectively (x... 1,1 ,y 1,1 ,z1),(x 1,2 ,y 1,2 ,z1),(x 1,3 ,y 1,3 ,z1),(x 1,4 ,y1,4 ,z1),(x 1,5 ,y 1,5 ,z1),(x 1,6 ,y 1,6 ,z1),(x 2,1 ,y 2,1 ,z2),(x 2,2 ,y 2,2 ,z2),(x 2,3 ,y 2,3 ,z2),(x 2,4 ,y 2,4 ,z2),(x 2,5 ,y 2,5 ,z2),(x 2,6 ,y 2,6 (z2). Figure 4 This is for illustrative purposes only. In practical applications, the first surface may not be a standard cylindrical surface, and the values ​​of n and p can be determined by the required accuracy of the calculation.

[0110] To simplify calculations, in one possible implementation, the first model can be represented by rectangular coordinates {x}. i,j ,y i,j ,z i |i=1,2,…,n;j=1,2,…,2p} is converted to cylindrical coordinates {R ext,i,j ,θ def,i,j Z i The formula for calculating |i=1,2,…,n;j=1,2,…,2p} is as follows:

[0111]

[0112] Figure 5 A three-dimensional example diagram of a first model provided in an embodiment of this application. Figure 6 A side view example of a first model provided in an embodiment of this application, as shown below. Figure 5 and Figure 6 As shown in the example above, the pipe is fitted with a surface by cubic B-spline interpolation and divided into multiple grid nodes to obtain the first model.

[0113] In practical applications, there are multiple ways to obtain the second model. In one example, the process of fitting a standard cylindrical surface based on the first model to obtain the second model includes:

[0114] The original point cloud is fitted with a central axis to obtain the central axis parameters corresponding to the pipe.

[0115] Based on the central axis parameters and the first model, the second model is obtained by fitting a standard cylindrical surface using the nonlinear least squares method.

[0116] Specifically, the original point cloud is fitted with a central axis, and the central axis parameters are obtained. For the convenience of calculation, the central axis can be aligned to the Z axis of the cylindrical coordinates, and the central axis is converted from the rectangular coordinates to the cylindrical coordinates. According to the obtained central axis parameters and the first model, a standard cylindrical surface is fitted, and a second model is obtained. The fitting method of the standard cylindrical surface can be various, and the nonlinear least squares method is taken as an example for illustration.

[0117] The equation of the standard cylindrical surface is set as:

[0118]

[0119] In the formula, (x0, y0, z0) is a point on the central axis, (i, j, k) is a unit vector of the axis direction, and R is the radius of the cylindrical cross section.

[0120] The nonlinear least squares method is used to define a straight line by a point x and a direction vector a = A / |A|, A is the axis of the cylinder, and f(x i , A) is the distance from the point x i to the straight line. The distance function is:

[0121] D(x i ) = f - R

[0122] The objective function is calculated as:

[0123] J(x, A, R) = ∑(f - R) 2

[0124] The minimum value of the objective function is obtained, and the cylindrical parameter R is obtained, so that the standard cylindrical surface is obtained. The standard cylindrical surface is divided into a plurality of nodes, including: dividing the standard cylindrical surface into n first axial sections and p first ring sections at equal intervals, taking the intersection set of the first curved surface and each first axial section and first ring section as a second model. In order to unify the calculation, the division method of the standard cylindrical surface is the same as that of the first curved surface, so that the nodes in the second model correspond to the nodes in the first model respectively.

[0125] In order to simplify the calculation, the second model can be converted from the rectangular coordinates to the cylindrical coordinates, and the conversion method is the same as that of the first model, which will not be described here.

[0126] Figure 7 An example diagram of the second model provided by an embodiment of the present application is shown in Figure 7 As described in the foregoing example, in order to restore the original state of the pipeline, the original point cloud is fitted with a central axis, and according to the central axis parameters and the first model, a standard cylindrical surface is fitted based on the nonlinear least squares method, and after being divided into a plurality of grid nodes, a second model is obtained.

[0127] In actual applications, the third model can be obtained in various ways. In one example, the third model is obtained by removing the nodes corresponding to the defect region in the first model, and performing surface fitting on the remaining nodes of the first model.

[0128] According to the first model, the curvature of each node in the first model is obtained based on a point cloud curvature algorithm.

[0129] The nodes with a curvature change rate exceeding a preset value are taken as defect feature points, and all the defect feature points are connected to form a defect boundary. The region surrounded by the defect boundary is segmented and deleted, wherein the curvature change rate of a node is the change rate of the curvature of the node relative to the curvature of an adjacent node.

[0130] The remaining nodes in the first model are fitted based on a B-spline surface interpolation method to obtain a second surface.

[0131] A plurality of second axial sections and a plurality of second ring sections are respectively and equidistantly divided on the second surface. According to the intersection points of the second surface and each of the second axial sections and the second ring sections, the third model is obtained, wherein the number of the second axial sections is the same as the number of the first axial sections, and the number of the second ring sections is the same as the number of the first axial sections.

[0132] Since the pipe depression is caused by the deformation of the pipe, the pipe depression is relatively smooth compared to the defect of the pipe. Therefore, the depression region of the pipe can be determined based on the curvature change of each point of the pipe. Specifically, based on the point cloud curvature algorithm, the curvature of each node in the first model is calculated, and the change rate of the curvature of each node relative to the curvature of an adjacent node is further calculated. The nodes with a change rate exceeding a predetermined value are taken as defect feature points. All the defect feature points are connected to obtain a defect boundary, and the region surrounded by the defect boundary is the defect region. The nodes corresponding to the defect region are deleted, and the remaining nodes are fitted and divided to obtain the third model.

[0133] Figure 8 An example diagram of the third model provided by an embodiment of the present application is shown in FIG. 2. Figure 8 As shown in FIG. 2, for the pipe as the foregoing example, the curvature mutation points in the first model are defined as defect feature points. After the nodes corresponding to the region surrounded by the defect feature points are deleted, the remaining nodes are reconstructed into a surface, and divided into a plurality of grid nodes to obtain the third model.

[0134] After the second model representing the original state of the pipe and the third model containing only the pipe depression are obtained, the pipe depression region can be analyzed. In one example, the deformation parameters of the depression region are obtained based on the second model and the third model, including:

[0135] According to geometric relations, a middle surface node of the pipe corresponding to each node in the second model and the third model is obtained as an original middle surface node and a recessed middle surface node of the pipe.

[0136] According to the original middle surface node and the corresponding recessed middle surface node, a radial displacement, a circumferential displacement and a deflection angle of each original middle surface node and the corresponding inner and outer wall nodes during the pipe recessing process are obtained as deformation parameters of the recessed area.

[0137] Specifically, according to geometric relations of the second model and the third model, the original middle surface node of the pipe before deformation corresponding to each node in the second model and the third model is calculated by taking a cylindrical coordinate calculation as an example and the corresponding recessed middle surface node after deformation And according to the triangular geometric relations of the nodes before and after deformation of the pipe, the displacement of the nodes is calculated.

[0138] Figure 9 A schematic diagram for calculating the deformation parameters of the pipe recessing provided by an embodiment of the present application is shown in Figure 9 The displacement calculation formula of the middle surface node is:

[0139]

[0140]

[0141]

[0142] In the formula, v m and w m are the circumferential displacement and the radial displacement of the middle surface node, respectively, and the unit is mm; is the angle difference before and after deformation of the middle surface node.

[0143] The wall thickness component is brought into the circumferential displacement and the radial displacement formula of the middle surface node, and the circumferential displacement, the radial displacement and the deflection angle of the inner and outer wall nodes can be calculated.

[0144] v=v m +t n sin(θ α )

[0145] w=w m -t n +t n cos(θ α )

[0146] θ α =θ tn -θ a

[0147] Assuming the direction of the wall thickness is still perpendicular to the outer surface after the pipe deformation, the slope k of the direction can be obtained tv is:

[0148]

[0149] The angle between the wall thickness direction and the polar axis is defined as θ tv :

[0150] θ tv = |arctan(k tv )|

[0151] In the formula, t n is the length of the deviation from the mid-surface node along the normal direction of the wall thickness, -t / 2≤t n ≤t / 2, and the unit is mm. When t n is -t / 2, it represents the inner surface of the pipe, and substituting the above formula obtains the circumferential displacement, radial displacement, and deflection angle of the pipe inner wall node. When t n is t / 2, it represents the outer surface of the pipe, and substituting the above formula obtains the circumferential displacement, radial displacement, and deflection angle of the pipe inner wall node; v and w are the circumferential displacement and radial displacement of the inner and outer surfaces of the concave pipe, respectively, and the unit is mm; θ α is the deflection angle of the pipe wall unit around the mid-surface node along the wall thickness direction during the deformation process, and the unit is rad. Thus, the deformation parameters of the concave area are obtained.

[0152] As the pipe in the foregoing example, Figure 10 is an example of a third model in a rectangular coordinate system provided by an embodiment of the present application, Figure 11 is an example of a third model in a cylindrical coordinate system provided by an embodiment of the present application, as shown in Figure 10 , Figure 11 After obtaining the third model representing the three-dimensional point cloud of the concave pipe in the rectangular coordinate system, the rectangular coordinate data is converted into cylindrical coordinate data by coordinate transformation using the cylindrical coordinate conversion formula. The grid nodes of the third model in the cylindrical coordinate are analyzed, and the pipe concave outer surface node coordinates and the node coordinates before and after the mid-surface deformation are extracted. According to the pipe concave deformation calculation formula, the concave depth of the composite concave pipe w=5.673 mm is calculated.

[0153] To further evaluate the composite concave of the pipe, in an example, the method further comprises:

[0154] Obtaining the axial length of the defect boundary as the defect length of the defect area;

[0155] Obtaining the circumferential length of the defect boundary as the defect width of the defect area;

[0156] Obtaining a radial length of the defect boundary as a defect depth of the defect region.

[0157] Specifically, according to the defect boundary in the first model, the axial length, the circumferential length and the radial length of the defect boundary are respectively obtained, so as to obtain the defect length, the defect width and the defect depth of the defect region of the pipeline.

[0158] Figure 12 An example diagram of the first model in the rectangular coordinate system provided by an embodiment of the present application is shown in FIG. 1. Figure 12 As shown in FIG. 1, the axial coordinates of the spatial points of the defect boundary are subtracted to obtain the defect length l = 11.755 mm of the defect region; the circumferential coordinates of the spatial points are subtracted to obtain the defect width w = 10.592 mm of the defect region. In order to avoid the influence of the pipeline concave region on the defect depth, the radial coordinates of the spatial points of the third model and the first model in the defect region are subtracted, and the maximum value is taken to obtain the defect depth d = 4.83 mm.

[0159] By analyzing the third model, it can be known that the required pressure head of the concave is spherical, and then the finite element modeling is performed in combination with the obtained concave parameters (the concave depth w = 5.673 mm) and the obtained defect parameters. The entire analysis process is divided into four steps:

[0160] (1) Apply internal pressure. Define the inner surface of the pipeline and apply internal pressure load;

[0161] (2) Establish contact. Apply a small radial displacement load pointing to the center axis of the pipeline on the reference point of the pressure head in the cylindrical coordinate system, and establish the contact between the pressure head and the pipeline. In this process, the contact stability control is used to resist the rigid body displacement until the contact is completely established;

[0162] (3) Apply displacement load. Apply all displacements to the reference point of the pressure head to fully concave the pipeline;

[0163] (4) Concave rebound. Apply a reverse displacement load to the concave pressure head to make the pressure head away from the surface of the pipeline, and analyze the safety state of the pipeline in the concave rebound process under the action of the pressure.

[0164] The process of causing the pipeline with corrosion defects to be concave by the pressure head load is simulated by the finite element simulation, and the suitability of the composite concave pipeline is evaluated in combination with the finite element calculation results.

[0165] The pipeline recess size acquisition method provided in the application comprises the following steps: 3D laser scanning is performed on a composite recess pipeline to obtain an original point cloud representing an outer surface of the pipeline, wherein the composite recess pipeline comprises a recess area and a defect area; surface fitting is performed on the original point cloud to obtain a first model; a standard cylindrical surface is fitted according to the first model to obtain a second model; nodes corresponding to the defect area in the first model are removed, and surface fitting is performed on the remaining nodes of the first model to obtain a third model; and deformation parameters of the recess area are obtained according to the second model and the third model. Based on the 3D laser scanning technology, the geometric data and the topography of the composite recess pipeline can be accurately and quickly obtained, and the errors caused by non-standard use of measuring tools by the measuring personnel and the vibration of the detector itself and other factors can be greatly avoided. Meanwhile, by establishing the second model representing the original state of the pipeline and the third model representing the pipeline containing only the recess, the influence of the corrosion area of the pipeline on the calculation of the recess deformation parameters is excluded, so that the independent recess parameters of the composite recess pipeline can be calculated and obtained, and the calculation accuracy of the recess size of the pipeline is effectively improved.

[0166] Embodiment two

[0167] Figure 13 The structure diagram of the pipeline recess size acquisition device provided in an embodiment of the application is shown in FIG. 1. As shown in FIG. 1, the pipeline recess size acquisition device provided in the embodiment can comprise: Figure 13

[0168] The first modeling module 131 is configured to perform 3D laser scanning on a composite recess pipeline to obtain an original point cloud representing an outer surface of the pipeline, wherein the composite recess pipeline comprises a recess area and a defect area, and surface fitting is performed on the original point cloud to obtain a first model.

[0169] The second modeling module 132 is configured to fit a standard cylindrical surface according to the first model to obtain a second model, and remove nodes corresponding to the defect area in the first model, and perform surface fitting on the remaining nodes of the first model to obtain a third model.

[0170] The obtaining module 133 is configured to obtain deformation parameters of the recess area according to the second model and the third model.

[0171] In actual application, the pipeline recess size acquisition device can be realized by a computer program, for example, application software, or can be realized as a medium storing a related computer program, for example, a U disk, a cloud disk, or can be realized by an entity device integrating or installing a related computer program, for example, a chip or a server.

[0172] ​Specifically, a 3D laser scan is performed on a pipe containing composite depressions, which includes depression regions and defect regions, to obtain the original point cloud data of the pipe's outer surface. A surface fitting is then performed on the original point cloud to obtain a first model, which characterizes the surface structure of the pipe's outer surface. The surface fitting can be implemented in reverse engineering software (such as Geomagic DeignX), and is not limited to this method.

[0173] Based on the first model, a standard cylindrical surface is fitted according to the point coordinates in the first model to obtain the second model, which is used to characterize the outer surface of the pipe without composite depressions; according to the point coordinates in the first model, the nodes corresponding to the pipe defect areas in the first model are removed to obtain the third model, which is used to characterize the outer surface of the pipe containing only depression areas and no defect areas.

[0174] Based on the second and third models, the concave area of ​​the pipeline can be delineated, thereby obtaining the deformation parameters of the concave area.

[0175] To improve data validity and reduce the difficulty of subsequent calculations, in one example, the first modeling module can specifically be used for:

[0176] The original point cloud is subjected to noise reduction and smoothing processing to remove sharp features and jagged edges.

[0177] Specifically, the original point cloud is denoised and smoothed to eliminate unnecessary sharp features, and excess jagged edges at both ends of the corresponding pipes are trimmed, thereby preprocessing the original point cloud data and improving data quality.

[0178] In practical applications, there can be multiple methods to obtain the first model. In one example, the first modeling module can also be used for;

[0179] Based on the B-spline surface interpolation method, the original point cloud is fitted with a surface to obtain the first surface;

[0180] The first surface is divided into multiple first axial sections and multiple first circumferential sections at equal intervals. The first model is obtained based on the intersection points of the first surface with each of the first axial sections and the first circumferential sections.

[0181] Specifically, since the original point cloud data is relatively scattered, it needs to be regularized, i.e., surface fitting. Surface fitting can effectively fill the data gaps in the original point cloud. There are various methods for surface fitting. Here, B-spline surface interpolation is used to fit the original point cloud to obtain the first surface.

[0182] For data point {P i The curve S fitted using a cubic B-spline function for |i=1,2,…,n} nConnect the two lines, because the cubic B-spline function has second-order continuity, and S can be calculated directly. n The curvature at any point on the curve S. n It is composed of (n-1) curve segments, and can be controlled by (n+2) vertices {B} i The fitting accuracy is controlled by |i=0,1,…,n+1}.

[0183] Due to the presence of corrosion defects, the reconstructed surface requires high accuracy; otherwise, it will significantly affect the defect characteristic parameters. n Above it and P i The corresponding point is t i It can be calculated by accumulating the chord length:

[0184]

[0185] In the formula, {L j |j=2,3,…,n} is a point P j-1 With P j The arc length between them.

[0186] The parameters of a surface in three-dimensional space are expressed as follows:

[0187] S(u,v)=[x(u,v),y(u,v),z(u,v)],(u,v)∈R 2

[0188] At this point, the surface is represented by two parameters, u and v, and the surface is mapped onto a uv-plane region in three-dimensional Euclidean space.

[0189] The cubic B-spline surface is represented as:

[0190]

[0191] In the formula, B i,j To control vertices, they can be connected to form a control polygon; N i,3 (u) and N j,3 (v) is a cubic B-spline basis function. According to the recursive formula proposed by de Boor and Cox, we have:

[0192]

[0193]

[0194] The first surface is obtained after surface reconstruction.

[0195] For subsequent data processing, the first curved surface is regularly meshed, including: dividing the first curved surface into n first axial sections and p first ring sections at equal intervals, taking the set of intersection points of the first curved surface and each first axial section and first ring section as the first model. i,j ,y i,j ,z i |i=1,2,…,n;j=1,2,…,2p}。

[0196] To simplify the calculation, in one possible implementation, the first model can be converted from the rectangular coordinates {x i,j ,y i,j ,z i |i=1,2,…,n;j=1,2,…,2p} to the cylindrical coordinates {R ext,i,j ,θ def,i,j ,Z i |i=1,2,…,n;j=1,2,…,2p}, and the calculation formula is as follows:

[0197]

[0198] In actual application, there can be multiple ways to obtain the second model. In one example, the second modeling module can be specifically used for:

[0199] Fitting a center axis of the original point cloud to obtain a center axis parameter corresponding to the pipeline;

[0200] Based on the center axis parameter and the first model, fitting a standard cylindrical surface based on a nonlinear least square method to obtain the second model.

[0201] Specifically, the original point cloud is fitted with a center axis, and the center axis parameter is obtained. To facilitate calculation, the center axis can be aligned to the Z axis of the cylindrical coordinates, and the center axis can be converted from rectangular coordinates to cylindrical coordinates. Based on the obtained center axis parameter and the first model, a standard cylindrical surface is fitted to obtain the second model. There can be multiple ways to fit the standard cylindrical surface, and the nonlinear least square method is taken as an example for illustration.

[0202] The equation of the standard cylindrical surface is set as:

[0203]

[0204] In the formula, (x0, y0, z0) is a point on the center axis, (i, j, k) is the unit vector of the axis direction, and R is the radius of the cylindrical section.

[0205] Using the nonlinear least square method, a straight line is defined by a point x and a direction vector α=A / |A|, A is the axis of the cylinder, and f(x i ,x,A) is the point xi Distance to straight line. Distance function is:

[0206] D(x i )=f-R

[0207] By calculating the objective function:

[0208] J(x,A,R)=∑(f-R) 2

[0209] The minimum value of which obtains the cylindrical parameter R, thereby obtaining the standard cylindrical surface. The standard cylindrical surface is divided into multiple nodes, including: dividing the standard cylindrical surface into n first axial sections and p first ring sections at equal intervals; taking the intersection of the first surface and each first axial section and first ring section as a second model. To unify the calculation, the standard cylindrical surface is divided in the same way as the first surface, so that the nodes in the second model correspond to the nodes in the first model respectively.

[0210] To simplify the calculation, the second model can be converted from rectangular coordinates to cylindrical coordinates, and the conversion method is the same as the first model, which will not be described here.

[0211] In practical applications, there are many ways to obtain the third model. In one example, the second modeling module can also be used to:

[0212] According to the first model, the curvature of each node in the first model is obtained based on a point cloud curvature algorithm;

[0213] Nodes with a curvature change rate exceeding a preset value are taken as defect feature points, and all defect feature points are connected to form a defect boundary. The area surrounded by the defect boundary is segmented and deleted, wherein the curvature change rate of a node is the change rate of the curvature of the node relative to the curvature of an adjacent node;

[0214] Based on the B-spline surface interpolation method, the remaining nodes in the first model are surface fitted to obtain a second surface;

[0215] A plurality of second axial sections and a plurality of second ring sections are respectively divided at equal intervals on the second surface. According to the intersection of the second surface and each second axial section and second ring section, the third model is obtained, wherein the number of second axial sections is the same as the number of first axial sections, and the number of second ring sections is the same as the number of first axial sections.

[0216] Since the pipe indentation is caused by pipe deformation, the indentation is relatively smooth compared to the defect. Therefore, the indentation region can be determined based on the curvature variation of each point of the pipe. Specifically, based on the point cloud curvature algorithm, the curvature of each node in the first model is calculated, and the rate of change of the curvature of each node relative to the curvature of the adjacent node is further calculated. The node whose rate of change exceeds a predetermined value is taken as a defect feature point. Connecting all the defect feature points, the defect boundary is obtained, and the area surrounded by the defect boundary is the defect region. The nodes corresponding to the defect region are deleted, and the remaining nodes are subjected to surface fitting and node division to obtain the third model.

[0217] After obtaining the second model representing the original state of the pipe and the third model containing only the pipe indentation, the pipe indentation region can be analyzed. In one example, the obtaining module can be specifically configured to:

[0218] According to the geometric relationship, the middle surface nodes of the pipe corresponding to each node in the second model and the third model are obtained as the original middle surface nodes and the indentation middle surface nodes of the pipe.

[0219] According to the original middle surface nodes and the corresponding indentation middle surface nodes, the radial displacement, circumferential displacement, and deflection angle of each original middle surface node and the corresponding inner and outer wall nodes during the pipe indentation process are obtained as the deformation parameters of the indentation region.

[0220] Specifically, according to the geometric relationship between the second model and the third model, the original middle surface nodes corresponding to each node in the second model and the third model before pipe deformation are calculated by taking the cylindrical coordinate calculation as an example. and the corresponding indentation middle surface nodes after deformation and according to the triangular geometric relationship of the nodes before and after pipe deformation, the displacement of the nodes is calculated.

[0221] The displacement formula of the middle surface node is:

[0222]

[0223]

[0224]

[0225] In the formula, v m and w m are the circumferential displacement and radial displacement of the middle surface node, respectively, with the unit of mm; is the angle difference before and after the deformation of the middle surface node.

[0226] The wall thickness component is brought into the circumferential displacement and radial displacement formula of the middle surface node, and the circumferential displacement, radial displacement, and deflection angle of the inner and outer wall nodes can be calculated.

[0227] v = v m + t n sin(θ α )

[0228] w = w m - t n + t n cos(θ α )

[0229] θ α = θ tn - θ a

[0230] Assuming the direction of the wall thickness is still perpendicular to the outer surface after the pipe deformation, the slope k of the direction can be obtained tv :

[0231]

[0232] Define the angle between the wall thickness direction and the polar axis as θ tv :

[0233] θ tv = |arctan(k tv )|

[0234] In the formula, t n is the length of the deviation from the middle surface node along the normal direction of the wall thickness, -t / 2≤t n ≤t / 2, unit: mm, when t n is -t / 2, it represents the inner surface of the pipe, and substituting the above formula obtains the circumferential displacement, radial displacement and deflection angle of the pipe inner wall node, t n is t / 2, it represents the outer surface of the pipe, and substituting the above formula obtains the circumferential displacement, radial displacement and deflection angle of the pipe inner wall node; v and w are respectively the circumferential displacement and radial displacement of the inner and outer surfaces of the concave pipe, unit: mm; θ α is the deflection angle of the pipe wall unit around the middle surface node in the wall thickness direction during the deformation process, unit: rad. Thus the deformation parameters of the concave area are obtained.

[0235] To further evaluate the composite concave of the pipe, in an example, the device further includes a second acquisition module, configured to:

[0236] acquire the axial length of the defect boundary as the defect length of the defect area;

[0237] acquire the circumferential length of the defect boundary as the defect width of the defect area;

[0238] acquire the radial length of the defect boundary as the defect depth of the defect area.

[0239] Specifically, according to the defect boundary in the first model, the lengths of the axial, circumferential and radial directions of the defect boundary are calculated respectively, so as to obtain the defect length, defect width and defect depth of the defect area of the pipeline.

[0240] The pipeline recess size acquisition device provided in the embodiment includes a stream processing module, a batch processing module and an application layer. The stream processing module is configured to perform simple stream aggregation on the network operation data acquired by the acquisition module in a stream processing manner to obtain an initial aggregation result. The batch processing module is configured to perform batch aggregation based on the initial aggregation result to obtain a final processing result provided to the application layer. The initial aggregation is performed to reduce the data processing amount, thereby reducing the intermediate state storage occupation, significantly reducing the data amount of subsequent batch processing, simplifying the subsequent aggregation algorithm, and improving the accuracy of data aggregation processing. Compared with the redundant processing mode, the processing procedure of the present application is more simple, thereby reducing the consumption of computing resources while ensuring the accuracy of network operation data processing.

[0241] Embodiment Three

[0242] Figure 14 A structural schematic diagram of an electronic device provided in the embodiment of the present disclosure is shown in FIG. 1, which includes: Figure 14

[0243] The electronic device further includes a memory 292, and can further include a communication interface 293 and a bus 294. The processor 291, the memory 292, and the communication interface 293 can communicate with each other through the bus 294. The communication interface 293 can be used for information transmission. The processor 291 can invoke the logical instructions in the memory 292 to execute the method of the above-mentioned embodiments.

[0244] In addition, the logical instructions in the memory 292 described above can be implemented in the form of a software functional unit and sold or used as an independent product, which can be stored in a computer readable storage medium.

[0245] The memory 292 as a computer readable storage medium can be used to store software programs, computer executable programs, such as program instructions / modules corresponding to the method in the embodiment of the present disclosure. The processor 291 executes the functions of the application and data processing by running the software programs, instructions and modules stored in the memory 292, that is, implements the method in the above-mentioned method embodiment.

[0246] ​The memory 292 can include a program storage area and a data storage area, where the program storage area can store an operating system, application programs required by at least one function; the data storage area can store data created according to the use of the terminal device, etc. In addition, the memory 292 can include a high-speed random access memory, and can also include a nonvolatile memory.

[0247] The embodiment of the present disclosure provides a kind of non-transitory computer readable storage medium, the computer readable storage medium has the computer execution instruction, the computer execution instruction is executed by processor when for realizing the method as described in the foregoing embodiments.

[0248] Embodiment four

[0249] The embodiment of the present disclosure provides a kind of computer program product, including computer program, computer program is executed by processor when realizing the method provided in any embodiment of the above present disclosure embodiment.

[0250] Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. For example, the application is not limited to the precise structures described and shown in the drawings, and it can be applied to other variations and adaptations as can be set forth in one or more independent claims issued after such time as independent claims are presented. The specification and examples are to be considered exemplary only, with the true scope and spirit of the application indicated by the following claims.

[0251] It is to be understood that the application is not limited to the precise construction described and shown in the drawings and that various modifications and changes can be made by those skilled in the art without departing from the scope of the application. The scope of the application is limited only by the claims that follow.

Claims

1. A method of acquiring a pipe recess dimension, characterized by, The method comprises the following steps: obtaining an original point cloud representing an outer surface of a composite recessed pipeline by 3D laser scanning, wherein the composite recessed pipeline comprises a recessed area and a defect area; and performing surface fitting on the original point cloud based on a B-spline surface interpolation method to obtain a first surface; dividing a plurality of first axial sections and a plurality of first circumferential sections on the first surface at equal intervals respectively, and obtaining a first model according to intersection points of the first surface and each of the first axial sections and the first circumferential sections; fitting a center axis of the pipeline based on the original point cloud to obtain a center axis parameter of the pipeline; determining a standard cylindrical section radius based on a nonlinear least squares method and a preset standard cylindrical surface equation according to the center axis parameter and the first model; fitting a standard cylindrical surface based on the standard cylindrical section radius; dividing a plurality of first axial sections and a plurality of first circumferential sections on the standard cylindrical surface at equal intervals respectively, and obtaining a second model according to intersection points of the standard cylindrical surface and each of the first axial sections and the first circumferential sections divided on the standard cylindrical surface; wherein the division manner of the standard cylindrical surface is the same as that of the first surface; and removing nodes corresponding to the defect area in the first model, and performing surface fitting on remaining nodes of the first model to obtain a third model; obtaining a deformation parameter of the recessed area according to the second model and the third model; the method of determining the standard cylindrical section radius based on the nonlinear least squares method and the preset standard cylindrical surface equation according to the center axis parameter and the first model comprises: setting the preset standard cylindrical surface equation as: In the formula, is a point on the central axis, is a unit vector in the axial direction, and R is the standard cylindrical cross-sectional radius; Using the non-linear least squares method, the point x is determined such that the distance of x to the direction vector A line is defined, A is the cylinder axis, is the point to the line; the distance function is: obtaining the standard cylindrical section radius by calculating a target function: the minimum value of which is the standard cylindrical section radius.

2. The method of claim 1, wherein, the method of removing nodes corresponding to the defect area in the first model, and performing surface fitting on remaining nodes of the first model to obtain a third model comprises: obtaining curvatures of each node in the first model based on a point cloud curvature algorithm according to the first model; connecting all defect feature points to form a defect boundary, and segmenting and deleting an area surrounded by the defect boundary, wherein the curvatures of the nodes are the change rates of the curvatures of the nodes relative to the curvatures of adjacent nodes; performing surface fitting on remaining nodes in the first model based on the B-spline surface interpolation method to obtain a second surface; dividing a plurality of second axial sections and a plurality of second circumferential sections on the second surface at equal intervals respectively, and obtaining the third model according to intersection points of the second surface and each of the second axial sections and the second circumferential sections, wherein the number of the second axial sections is the same as that of the first axial sections, and the number of the second circumferential sections is the same as that of the first axial sections.

3. The method of claim 2, wherein, the method of obtaining a deformation parameter of the recessed area according to the second model and the third model comprises: obtaining center surface nodes of the pipeline corresponding to each node in the second model and the third model as original center surface nodes and recessed center surface nodes of the pipeline according to geometric relationships. According to the original middle surface node and the corresponding recessed middle surface node, the radial displacement, the ring direction displacement and the deflection angle of each original middle surface node and the corresponding inner and outer wall node in the pipeline recessing process are obtained as the deformation parameters of the recessed area.

4. The method of claim 3, wherein, The method further comprises: obtaining the axial length of the defect boundary as the defect length of the defect area; obtaining the ring length of the defect boundary as the defect width of the defect area; obtaining the radial length of the defect boundary as the defect depth of the defect area.

5. The method according to any one of claims 1 to 4, characterized in that, Before the original point cloud is fitted to obtain the first model, the method further comprises: performing noise reduction and smoothing processing on the original point cloud to remove sharp features and burrs.

6. A pipe recess dimension acquisition device characterized by comprising: Comprise: A first modeling module is configured to obtain an original point cloud representing an outer surface of a composite recessed pipeline by performing 3D laser scanning on the composite recessed pipeline, wherein the composite recessed pipeline comprises a recessed area and a defect area; and perform surface fitting on the original point cloud based on a B-spline surface interpolation method to obtain a first surface; a plurality of first axial sections and a plurality of first ring sections are equally spaced on the first surface; and a first model is obtained according to the intersection points of the first surface and each of the first axial sections and the first ring sections. A second modeling module is configured to fit a middle axis of the original point cloud to obtain middle axis parameters of the pipeline; determine a standard cylindrical section radius based on a nonlinear least squares method and a preset standard cylindrical surface equation according to the middle axis parameters and the first model; fit a standard cylindrical surface based on the standard cylindrical section radius; a plurality of first axial sections and a plurality of first ring sections are equally spaced on the standard cylindrical surface; a second model is obtained according to the intersection points of the standard cylindrical surface and each of the first axial sections and the first ring sections on the standard cylindrical surface; wherein the division method of the standard cylindrical surface is the same as that of the first surface; and remove the nodes corresponding to the defect area in the first model, and perform surface fitting on the remaining nodes of the first model to obtain a third model. An obtaining module is configured to obtain deformation parameters of the recessed area according to the second model and the third model. When the standard cylindrical section radius is determined based on a nonlinear least squares method and a preset standard cylindrical surface equation according to the middle axis parameters and the first model, the second modeling module is specifically configured to: set the preset standard cylindrical surface equation as: wherein is a point on the central axis, is a unit vector in the direction of the axis, and R is the standard cylindrical cross-sectional radius; Using the non-linear least squares method, the point x and the direction vector A line is defined, A is the cylinder axis, is the point to the line; the distance function is: obtain the standard cylindrical section radius by calculating the objective function: The minimum value of the objective function is the standard cylindrical section radius.

7. An electronic device, comprising: Comprise: A processor and a memory in communication with the processor; The memory stores computer execution instructions; The processor executes the computer execution instructions stored in the memory to implement the method of any one of claims 1-5.

8. A computer-readable storage medium, characterized in that, The computer readable storage medium stores computer execution instructions, and the computer execution instructions are executed by the processor to implement the method of any one of claims 1-5.

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