Method and apparatus for generating a finite element model of a building component based on point cloud data

Abstract

The application provides a method for generating a finite element model of a building component based on point cloud data, comprising: obtaining original point cloud data of the building component, and obtaining a plurality of regional point cloud data and a plurality of cross-section point cloud data according to the original point cloud data; obtaining point cloud data of each board region in each cross section according to the plurality of regional point cloud data and the plurality of cross-section point cloud data, and fitting and segmenting to obtain a geometric model matched with the shape of each board in each cross section; obtaining an average geometric model of a plurality of boards according to the geometric model matched with the shape of each board in each cross section, laying out grid points according to the average geometric model of the plurality of boards, and stretching to obtain a standard finite element model; calculating an initial defect value of the building component according to the geometric model and the standard finite element model, and adding the initial defect value to the standard finite element model to obtain a finite element model of the building component. The application solves the problem that a BIM model and a finite element model of a building component are incompatible.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of finite element model generation, and particularly relates to a method and device for generating a finite element model of a building component based on point cloud data. BACKGROUND

[0002] The building model directly generated from the point cloud data is a solid, while various structural design and analysis software use beam elements and shell elements, and thus there is a problem of incompatibility between the BIM model and the finite element analysis. SUMMARY

[0003] The present application aims to at least partially solve one of the technical problems in the related art.

[0004] To this end, a first object of the present application is to provide a method for generating a finite element model of a building component based on point cloud data, which solves the technical problem of incompatibility between the BIM model and the finite element model of the building component, and improves the compatibility of the building component by processing the original point cloud of the building component to obtain the finite element model of the building component.

[0005] A second object of the present application is to provide a device for generating a finite element model of a building component based on point cloud data.

[0006] A third object of the present application is to provide a non-transitory computer readable storage medium.

[0007] To achieve the above objects, a first aspect of the present application provides a method for generating a finite element model of a building component based on point cloud data, comprising: obtaining original point cloud data of a building component, and obtaining a plurality of regional point cloud data and a plurality of cross-sectional point cloud data according to the original point cloud data, wherein the plurality of regional point cloud data respectively belong to a plurality of different plates; obtaining point cloud data of each plate region in each cross section according to the plurality of regional point cloud data and the plurality of cross-sectional point cloud data, and fitting and segmenting to obtain a geometric model matching the shape of each plate in each cross section according to the point cloud data of each plate region in each cross section; obtaining an average geometric model of the plurality of plates according to the geometric model matching the shape of each plate in each cross section, laying out grid points according to the average geometric model of the plurality of plates, and stretching to obtain a standard finite element model; calculating an initial defect value of the building component according to the geometric model and the standard finite element model, and adding the initial defect value to the standard finite element model to obtain a finite element model of the building component.

[0008] Optionally, in an embodiment of the present application, obtaining the plurality of regional point cloud data and the plurality of cross-sectional point cloud data according to the original point cloud data comprises:

[0009] selecting an initial end section plane of the original point cloud data, wherein the initial end section plane comprises a first section plane and a second section plane;

[0010] taking point cloud data between the first section plane and the second section plane as sub-point cloud data, and obtaining a plurality of regional point cloud data according to the sub-point cloud data;

[0011] obtaining a plurality of sections between the first section plane and the second section plane, and obtaining a plurality of section point cloud data according to the sub-point cloud data.

[0012] Optionally, in an embodiment of the present application, according to the plurality of regional point cloud data and the plurality of section point cloud data, point cloud data of each plate region in each section is obtained, and a geometric model matched with the shape of each plate in each section is fitted and segmented according to the point cloud data of each plate region in each section, comprising:

[0013] taking intersection of the plurality of regional point cloud data and the plurality of section point cloud data to obtain point cloud data belonging to each plate region in each section respectively;

[0014] fitting and segmenting a geometric model matched with the shape of each plate in each section according to the point cloud data of each plate region in each section by a segmentation algorithm to obtain a geometric model corresponding to the point cloud data of each plate region in each section;

[0015] wherein, when the point cloud data of each plate region in each section only contains a single line, a double-line geometric model is formed according to a preset thickness offsetting the single line.

[0016] Optionally, in an embodiment of the present application, characterized in that, before obtaining an average geometric model of a plurality of plates according to the geometric model matched with the shape of each plate in each section, comprising:

[0017] connecting the centroid of the geometric model of the first section plane and the centroid of the corresponding geometric model of the second section plane;

[0018] if the included angle between the centroid connecting line and the axis is greater than a first preset threshold, the centroid connecting line is taken as a new axis, the first section plane and the second section plane are reselected, the above steps are repeated until the iteration times is greater than a second preset threshold and / or the included angle between the centroid connecting line and the axis is less than or equal to the first preset threshold.

[0019] Optionally, in an embodiment of the present application, according to the geometric model matched with the shape of each plate in each section, an average geometric model of a plurality of plates is obtained, comprising:

[0020] obtaining an average geometric model of a plurality of plates according to the geometric models corresponding to a plurality of plate regions;

[0021] The average geometric model of the plurality of plate members is obtained by extracting mathematical expressions from the plurality of geometric models respectively, taking average values of parameters of the plurality of mathematical expressions, and obtaining the average geometric model of the plurality of plate members.

[0022] Optionally, in an embodiment of the present application, the standard finite element model is obtained by arranging and stretching grid points according to the average geometric model of the plurality of plate members, and the standard finite element model comprises:

[0023] The average geometric model of the plurality of plate members is obtained by extracting mathematical expressions from the plurality of geometric models respectively, taking average values of parameters of the plurality of mathematical expressions, and obtaining the average geometric model of the plurality of plate members.

[0024] The average geometric model of the plurality of plate members is obtained by extracting mathematical expressions from the plurality of geometric models respectively, taking average values of parameters of the plurality of mathematical expressions, and obtaining the average geometric model of the plurality of plate members.

[0025] The average geometric model of the plurality of plate members is obtained by extracting mathematical expressions from the plurality of geometric models respectively, taking average values of parameters of the plurality of mathematical expressions, and obtaining the average geometric model of the plurality of plate members.

[0026] The average geometric model of the plurality of plate members is obtained by extracting mathematical expressions from the plurality of geometric models respectively, taking average values of parameters of the plurality of mathematical expressions, and obtaining the average geometric model of the plurality of plate members.

[0027] Optionally, in an embodiment of the present application, the initial defect value of the building component is calculated according to the geometric model and the standard finite element model, and the initial defect value of the building component comprises:

[0028] The average geometric model of the plurality of plate members is obtained by extracting mathematical expressions from the plurality of geometric models respectively, taking average values of parameters of the plurality of mathematical expressions, and obtaining the average geometric model of the plurality of plate members.

[0029] The average geometric model of the plurality of plate members is obtained by extracting mathematical expressions from the plurality of geometric models respectively, taking average values of parameters of the plurality of mathematical expressions, and obtaining the average geometric model of the plurality of plate members.

[0030] The average geometric model of the plurality of plate members is obtained by extracting mathematical expressions from the plurality of geometric models respectively, taking average values of parameters of the plurality of mathematical expressions, and obtaining the average geometric model of the plurality of plate members.

[0031] The average geometric model of the plurality of plate members is obtained by extracting mathematical expressions from the plurality of geometric models respectively, taking average values of parameters of the plurality of mathematical expressions, and obtaining the average geometric model of the plurality of plate members.

[0032] Optionally, in an embodiment of the present application, the initial defect value of the building component is calculated according to the geometric model and the standard finite element model, and the initial defect value of the building component comprises:

[0033] The average geometric model of the plurality of plate members is obtained by extracting mathematical expressions from the plurality of geometric models respectively, taking average values of parameters of the plurality of mathematical expressions, and obtaining the average geometric model of the plurality of plate members.

[0034] The average geometric model of the plurality of plate members is obtained by extracting mathematical expressions from the plurality of geometric models respectively, taking average values of parameters of the plurality of mathematical expressions, and obtaining the average geometric model of the plurality of plate members.

[0035] The grid points of the standard finite element model are orthogonally projected onto multiple single-line models to obtain the parameter values ​​of the grid points. Based on the parameter values ​​of the point cloud data and the local coordinate deviation, a smooth interpolation method is used to obtain the local deviation corresponding to the parameter values ​​of the grid points.

[0036] To achieve the above objectives, a second aspect of this application provides an apparatus for generating finite element models of building components based on point cloud data, comprising:

[0037] The acquisition module is used to acquire the original point cloud data of building components, and to obtain multiple region point cloud data and multiple cross-sectional point cloud data based on the original point cloud data. The multiple region point cloud data belong to multiple different plates.

[0038] The geometric model acquisition module is used to obtain the point cloud data of each plate region in each cross section based on the point cloud data of multiple regions and the point cloud data of multiple cross sections, and to fit and segment the point cloud data of each plate region in each cross section to obtain a geometric model that matches the shape of each plate in each cross section.

[0039] The standard finite element model acquisition module is used to obtain the average geometric model of multiple plates based on the geometric model that matches the shape of each plate in each section, and to set up mesh points and stretch them based on the average geometric model of multiple plates to obtain the standard finite element model.

[0040] The finite element model acquisition module is used to calculate the initial defect values ​​of building components based on the geometric model and the standard finite element model, and then attach the initial defect values ​​to the standard finite element model to obtain the finite element model of the building components.

[0041] To achieve the above objectives, a third aspect of this application provides a non-transitory computer-readable storage medium that, when the instructions in the storage medium are executed by a processor, enables the execution of a method for generating a finite element model of a building component based on point cloud data.

[0042] The method, apparatus, and non-temporary computer-readable storage medium for generating finite element models of building components based on point cloud data in this application embodiment solve the technical problem of incompatibility between existing BIM models and finite element models of building components. By processing the original point cloud of the building component, the finite element model of the building component is obtained, thereby improving the compatibility of the building component.

[0043] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0044] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description, taken in conjunction with the following drawings of exemplary embodiments of the present application, wherein:

[0045] Figure 1 A flowchart of a method for generating a finite element model of a building component based on point cloud data according to an embodiment of the present application;

[0046] Figure 2 A structural diagram of a device for generating a finite element model of a building component based on point cloud data according to an embodiment of the present application. DETAILED DESCRIPTION

[0047] The embodiments of the present application are described in detail below with reference to the accompanying drawings, in which the same or similar components have the same reference numbers throughout the several figures and identical or similar components are denoted by the same reference numerals, and a description thereof will not be repeated. The embodiments described below are exemplary and are intended to explain the present application, and should not be understood as limiting the present application.

[0048] The method and device for generating a finite element model of a building component based on point cloud data according to the embodiments of the present application are described below with reference to the accompanying drawings.

[0049] Figure 1 A flowchart of a method for generating a finite element model of a building component based on point cloud data according to an embodiment of the present application;

[0050] As shown in the method for generating a finite element model of a building component based on point cloud data, the method comprises the following steps: Figure 1

[0051] Step 101, obtaining original point cloud data of a building component, and obtaining a plurality of regional point cloud data and a plurality of cross-sectional point cloud data according to the original point cloud data, wherein the plurality of regional point cloud data respectively belong to a plurality of different plates;

[0052] Step 102, obtaining point cloud data of each plate region in each cross section according to the plurality of regional point cloud data and the plurality of cross-sectional point cloud data, and fitting and segmenting to obtain a geometric model matching the shape of each plate in each cross section according to the point cloud data of each plate region in each cross section;

[0053] Step 103, obtaining an average geometric model of a plurality of plates according to the geometric model matching the shape of each plate in each cross section, and laying out grid points and stretching according to the average geometric model of the plurality of plates to obtain a standard finite element model;

[0054] Step 104, calculating an initial defect value of the building component according to the geometric model and the standard finite element model, and adding the initial defect value to the standard finite element model to obtain a finite element model of the building component. ​

[0055] The method for generating a building component finite element model based on point cloud data according to the embodiments of the present application obtains original point cloud data of a building component, and obtains a plurality of regional point cloud data and a plurality of cross-section point cloud data according to the original point cloud data, wherein the plurality of regional point cloud data respectively belong to a plurality of different plates; according to the plurality of regional point cloud data and the plurality of cross-section point cloud data, point cloud data of each plate region in each cross section is obtained, and a geometric model matched with the shape of each plate in each cross section is fitted and segmented according to the point cloud data of each plate region in each cross section; an average geometric model of the plurality of plates is obtained according to the geometric model matched with the shape of each plate in each cross section, a grid point is laid out according to the average geometric model of the plurality of plates and is stretched to obtain a standard finite element model; an initial defect value of the building component is calculated according to the geometric model and the standard finite element model, and the initial defect value is added to the standard finite element model to obtain a finite element model of the building component. Thus, the technical problem that the building component BIM model and the finite element model are incompatible is solved, the finite element model of the building component is obtained by processing the original point cloud of the building component, and the compatibility of the building component is improved.

[0056] The original point cloud of the building component is obtained by photogrammetry, three-dimensional laser scanning or the like, wherein the original point cloud format can be a common point cloud format such as pcd and asc.

[0057] Further, in the embodiments of the present application, the plurality of regional point cloud data and the plurality of cross-section point cloud data are obtained according to the original point cloud data, which comprises:

[0058] The initial end cross-section plane of the original point cloud data is selected, wherein the initial end cross-section plane comprises a first cross-section plane and a second cross-section plane;

[0059] The point cloud data between the first cross-section plane and the second cross-section plane is taken as sub-point cloud data, and the plurality of regional point cloud data is obtained according to the sub-point cloud data;

[0060] A plurality of cross sections between the first cross-section plane and the second cross-section plane are obtained, and the plurality of cross-section point cloud data is obtained according to the sub-point cloud data.

[0061] In the embodiments of the present application, the initial end cross-section plane of the original point cloud data is selected, wherein the initial end cross-section plane comprises a first cross-section plane and a second cross-section plane, which comprises:

[0062] A minimum bounding box of the original point cloud data is established, wherein the minimum bounding box is a minimum cuboid that encloses the original point cloud data;

[0063] The longest side of the minimum bounding box is taken as an axis, and two faces perpendicular to the axis at two ends of the minimum bounding box are taken as a first end face and a second end face respectively, a plane at a first preset distance from the first end face is taken as a first section plane, and a plane at a first preset distance from the second end face is taken as a second section plane.

[0064] In the embodiments of the present application, a minimum bounding box of the original point cloud (i.e., a minimum cuboid enclosing all points of the original point cloud) is established, the longest side of the minimum bounding box is taken as an axis direction, two faces perpendicular to the axis are taken as end faces, and planes at positions of r x L from the end faces at two ends are taken as a first section plane P1 and a second section plane P2, where the axis length is L, and r is a small non-negative value, for example, 5%.

[0065] In the embodiments of the present application, the point cloud data between the first section plane and the second section plane is taken as sub-point cloud data, and a plurality of regional point cloud data is obtained according to the sub-point cloud data, where the plurality of regional point cloud data respectively belongs to a plurality of different plates, and includes:

[0066] The sub-point cloud data is projected onto a plane along the axis direction to obtain a plane pattern;

[0067] The plane pattern is provided to a user end, and a plurality of regional sub-point cloud data belonging to different plates is obtained according to feedback of the user end.

[0068] In the embodiments of the present application, points in the original point cloud falling between the section planes are screened to form a sub-point cloud. The sub-point cloud is projected onto a plane along the axis direction to provide a graphical interface to a user, and m regional sub-point clouds R[0:m] belonging to different steel plates are selected by the user.

[0069] In the embodiments of the present application, a plurality of sections between the first section plane and the second section plane is obtained, and a plurality of section point cloud data is obtained according to the sub-point cloud data, including:

[0070] Between the first section plane and the second section plane, a plane is taken every second preset distance along the axis direction from the first section plane to obtain a plurality of sections between the first section plane and the second section plane;

[0071] According to the sub-point cloud data, point cloud data of each section is obtained, so as to obtain a plurality of section point cloud data;

[0072] Wherein, the point cloud data in the sub-point cloud data with a distance less than half of the second preset distance from the section is taken as the point cloud data of the section.

[0073] In the embodiments of the present application, a distance threshold parameter t (a non-negative value) is taken, the first section plane P1 is copied along the axis direction to the second section plane P2, a copy is made every distance t, forming a sequence P[0:n] composed of n section planes; for each section plane P[i] in the sequence, points in the sub-point cloud with a distance less than t / 2 from the section plane are screened to form a section sub-point cloud S[i]. This is done for each section plane, and a sequence S[0:n] composed of n section point clouds is obtained.

[0074] Further, in the embodiments of the present application, the point cloud data of each plate region in each section is obtained according to the plurality of region point cloud data and the plurality of section point cloud data, and a geometric model matching the shape of each plate in each section is fitted and segmented according to the point cloud data of each plate region in each section, including:

[0075] The intersection of the plurality of region point cloud data and the plurality of section point cloud data is taken to obtain point cloud data belonging to each plate region in each section, respectively;

[0076] According to the point cloud data of each plate region in each section, a geometric model matching the shape of each plate in each section is fitted and segmented by a segmentation algorithm, to obtain a geometric model corresponding to the point cloud data of each plate region in each section;

[0077] When the point cloud data of each plate region in each section only contains a single line, a double-line geometric model is formed according to a preset thickness offset from the single line.

[0078] In the embodiments of the present application, for each section sub-point cloud S[i] and region sub-point cloud R[j], their intersection SR[i,j] = S[i]∩R[j] is taken, which means the set of points in the ith section falling within the plate region j range.

[0079] In the embodiments of the present application, mathematical models of common geometric figures such as parallel line segments, parallel circular arcs, concentric circles, etc. are constructed, and based on the RANSAC (Random Sample Consensus) algorithm, a geometric model most matching the plate shape in each intersection SR[i,j] is fitted and segmented, which is recorded as G[i,j], and thus m×n geometric models G[0:n,0:m] located at different positions of the axis and belonging to different regions are obtained.

[0080] In some cases, due to scanning angles and other reasons, the point cloud only contains a single line segment, a single circular arc, or a single circle, and a user needs to specify a thickness value to form a double-line geometric model according to a thickness offset from the single line, that is, G[0:n,0:m] are all double-line models.

[0081] Further, in the embodiments of the present application, the average geometric model of the plurality of plate members is obtained according to the geometric model matching the shape of each plate member in each cross section, and the method comprises:

[0082] connecting the centroid of the geometric model of the first cross plane and the centroid of the corresponding geometric model of the second cross plane;

[0083] if the included angle between the centroid connecting line and the axis is greater than the first preset threshold value, the centroid connecting line is taken as a new axis, the first cross plane and the second cross plane are reselected, and the above steps are repeated until the iteration number is greater than the second preset threshold value and / or the included angle between the centroid connecting line and the axis is less than or equal to the first preset threshold value.

[0084] In the embodiments of the present application, if the connecting line of the centroids C[0] and C[n-1] of the geometric models G[0,0:m] and G[n-1,0:m] of the end portion is not parallel to the axis taken in the second step (i.e. the included angle between the two is greater than a certain threshold value), the connecting line of C[0] and C[n-1] is taken as a new axis, and the plane passing through C[0] and C[n-1] and perpendicular to the new axis is a new end cross plane, and the above steps are repeated until the iteration number is greater than a certain threshold value or the included angle of the end centroid connecting line is less than or equal to the threshold value.

[0085] Further, in the embodiments of the present application, the average geometric model of the plurality of plate members is obtained according to the geometric model matching the shape of each plate member in each cross section, and the method comprises:

[0086] obtaining the average geometric model of the plurality of plate members according to the geometric models corresponding to the plurality of plate member regions;

[0087] wherein the plurality of mathematical expressions of the same plate member region are obtained by respectively extracting mathematical expressions of the plurality of geometric models belonging to the same plate member region, and the average geometric model of the plate member is obtained by taking the average value of the parameters of the plurality of mathematical expressions.

[0088] In the embodiments of the present application, the mathematical expressions of the geometric models G[0:n,j] belonging to the same specified region j are extracted, and the average value (not limited to the average value method) of the parameters of the n expressions is taken to form a representative mathematical expression as the average geometric model G 平均 [j].

[0089] Further, in the embodiments of the present application, the standard finite element model is obtained by arranging grid points and stretching according to the average geometric model of the plurality of plate members, and the method comprises:

[0090] selecting the middle parallel line of the average geometric model of the plurality of plate members to obtain a plurality of average single-line models;

[0091] Based on the preset grid size and the line lengths in multiple average single-line models, calculate the actual grid size and place the grid points according to the actual grid size.

[0092] Calculate the intersection points of multiple average single-line models pairwise, and adjust the grid points according to the intersection point positions;

[0093] Based on the preset mesh size and axis length, the stretching dimensions are calculated, and the adjusted mesh points are stretched along the axis direction according to the stretching dimensions to obtain the standard finite element model.

[0094] In this embodiment, the average geometric model with parallel line segments is selected by taking the middle parallel line (similarly, the middle parallel arc is taken for parallel arcs, and the middle circle is taken for concentric circles) to form an average single-line model set H. 平均 [0:m].

[0095] In this embodiment of the application, a grid size a is set, and the average single-line model H is... 平均 [j] Calculate the average line segment length or arc length s of the single-line model, and calculate the actual fabric size a based on the line segment length or arc length s of the single-line model. 实际 =s / (max(round(s / a),1), where round is the rounding function. In each average single-line model H 平均 [j] every a 实际 Layout the grid points.

[0096] In this embodiment of the application, the average single-line model set H 平均 [0:m] Calculate the intersection points of the average single-line model pairwise, and adjust the layout of the points as needed. If the distance from the original grid point is less than or equal to a preset threshold, the original grid point is adjusted to the intersection point; if the distance from the original grid point is greater than the preset threshold, a new grid point is generated.

[0097] In this embodiment, the stretching dimension a is calculated based on the mesh size a and the axis length l. 拉伸 =l / (max(round(l / a),1), where round is the rounding function. This applies to every stretching dimension a along the axial direction. 拉伸 A shell element mesh is formed with a total stretching length of l, resulting in a standard finite element model.

[0098] Furthermore, in this embodiment of the application, the initial defect value of the building component is calculated based on the geometric model and the standard finite element model, including:

[0099] By selecting the middle parallel lines of multiple geometric models, multiple single-line models are obtained;

[0100] Calculate the local deviations between the mesh points of the standard finite element model and multiple single-line models;

[0101] The coordinate difference between the centroids of multiple single-line models and the average single-line model of each plate is calculated as the overall deviation;

[0102] The initial defect values ​​of the grid points of the building components are obtained based on the local and overall deviations.

[0103] In this embodiment of the application, the average geometric model with parallel line segments is represented by the middle parallel line (similarly, the middle parallel arc is represented by the parallel arc, and the middle circle is represented by the concentric circle), forming a set of single-line models H[0:n,0:m]. The local deviation d between the mesh points of the standard finite element model and the multiple single-line models is calculated. 局部 Calculate the overall deviation d of the single-line model. 整体 The local deviation d 局部 and overall deviation d 整体 The superposition of values ​​is used as the initial defect value for the mesh points in the standard finite element model.

[0104] The initial defect value d = d at the mesh point of the standard finite element model 局部 +d 整体 =(Δx) 局部 +Δx 整体 ,Δy 局部 +Δy 整体 ).

[0105] For the single-line model H[i,j], the geometric model H is calculated using the single-line average geometric model H. 平均 The coordinate difference between the centroids of [j] is denoted as d. 整体 =(Δx) 整体 ,Δy 整体 ).

[0106] Furthermore, in the embodiments of this application, calculating the local deviations between the mesh points of the standard finite element model and multiple single-line models includes:

[0107] Obtain point cloud data corresponding to bilines of multiple geometric models;

[0108] The point cloud data is orthogonally projected onto the corresponding geometric model to obtain the parameter values ​​and local coordinate deviations of the point cloud data.

[0109] The grid points of the standard finite element model are orthogonally projected onto multiple single-line models to obtain the parameter values ​​of the grid points. Based on the parameter values ​​of the point cloud data and the local coordinate deviation, a smooth interpolation method is used to obtain the local deviation corresponding to the parameter values ​​of the grid points.

[0110] In this embodiment of the application, after fitting and segmenting the geometric model that best matches the shape of the plate in each intersection SR[i,j] based on the RANSAC (Random Sample Consensus) algorithm, point cloud data corresponding to the biline of multiple geometric models can be obtained.

[0111] For the geometric model G[i,j], its double line corresponds to the subset SR[i,j] of the original point cloud. For any point A in the subset, the orthogonal projection of A to the geometric model G[i,j] can obtain its parameter value u and local coordinate deviation d 局部 =(Δx 局部 ,Δy 局部 ), wherein the parameter value u is the parameter coordinate of the point of the orthogonal projection of A to the geometric model on the geometric model, u∈[0,1]; the local coordinate deviation d 局部 is the coordinate deviation value of the point A and the point of the orthogonal projection of A to the geometric model. For all points in the subset, the operation can obtain a series of parameter values U and local coordinate deviations D 局部 .

[0112] For any grid point M of the standard finite element model, it corresponds to the geometric model G[i,j] (single line model H[i,j]) and has a parameter value u M , the above U and D 局部 are used as the reference data for interpolation, and a smooth interpolation method (for example, SmoothBivariateSpline) is used to obtain the local deviation d M corresponding to the parameter u 局部,M .

[0113] The initial defect value of each grid point can be added to the standard finite element model in two ways:

[0114] 1) Directly superimposed with the node coordinates;

[0115] 2) Based on the initial displacement field element format of a specific software to provide an input text.

[0116] After the initial defect value is added to the standard finite element model, the finite element model of the building component is obtained, all grid node numbers and node coordinates of the building component finite element model are collected to form a text in the finite element input file format, that is, an analysis grid that can be used for finite element software can be exported.

[0117] Figure 2 It is a structural schematic view of a device for generating a building component finite element model based on point cloud data provided in Embodiment Two of the present application.

[0118] As shown in Figure 2 , the device for generating a building component finite element model based on point cloud data comprises:

[0119] The acquisition module 10 is configured to acquire original point cloud data of the building component, and obtain a plurality of area point cloud data and a plurality of cross-section point cloud data according to the original point cloud data, wherein the plurality of area point cloud data respectively belong to a plurality of different plates;

[0120] The geometric model acquisition module 20 is configured to obtain point cloud data of each plate area in each cross section according to the plurality of area point cloud data and the plurality of cross-section point cloud data, and fit and segment to obtain a geometric model matched with the shape of each plate in each cross section according to the point cloud data of each plate area in each cross section.

[0121] The standard finite element model acquisition module 30 is configured to obtain an average geometric model of the plurality of plates according to the geometric model matched with the shape of each plate in each cross section, and arrange grid points and stretch according to the average geometric model of the plurality of plates to obtain a standard finite element model.

[0122] The finite element model acquisition module 40 is configured to calculate an initial defect value of the building component according to the geometric model and the standard finite element model, and attach the initial defect value to the standard finite element model to obtain a finite element model of the building component.

[0123] The device for generating a finite element model of a building component based on point cloud data provided by the embodiment of the application comprises an acquisition module configured to acquire original point cloud data of the building component, and obtain a plurality of area point cloud data and a plurality of cross-section point cloud data according to the original point cloud data, wherein the plurality of area point cloud data respectively belong to a plurality of different plates; a geometric model acquisition module configured to obtain point cloud data of each plate area in each cross section according to the plurality of area point cloud data and the plurality of cross-section point cloud data, and fit and segment to obtain a geometric model matched with the shape of each plate in each cross section according to the point cloud data of each plate area in each cross section; a standard finite element model acquisition module configured to obtain an average geometric model of the plurality of plates according to the geometric model matched with the shape of each plate in each cross section, and arrange grid points and stretch according to the average geometric model of the plurality of plates to obtain a standard finite element model; and a finite element model acquisition module configured to calculate an initial defect value of the building component according to the geometric model and the standard finite element model, and attach the initial defect value to the standard finite element model to obtain a finite element model of the building component. Thus, the technical problem that the BIM model and the finite element model of the building component are incompatible can be solved, the finite element model of the building component is obtained by processing the original point cloud of the building component, and the compatibility of the building component is improved.

[0124] In order to implement the above-mentioned embodiments, the application further provides a non-transitory computer-readable storage medium having a computer program stored thereon, and the computer program is executed by a processor to implement the method for generating a finite element model of a building component based on point cloud data.

[0125] In the description of the application, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the application. The illustrative description of the above terms in the specification does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any suitable manner in one or more embodiments or examples. In addition, the skilled person can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples, without contradiction.

[0126] In addition, the terms "first", "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the application, the meaning of "multiple" is at least two, for example two, three, etc., unless otherwise specifically limited.

[0127] Any process or method descriptions in flow charts or described elsewhere herein can be understood as representing code modules, segments, or portions of code that include one or more executable instructions for implementing the specified logic functions or processes, and the preferred embodiments of the application include additional implementations in which the order of execution or the functions themselves can be changed, including according to the functionality involved, stored by the modules, segments, or portions of code, and the skilled person in the art of the embodiments of the application should be understood.

[0128] The logic and / or steps represented in the flowcharts and / or described herein, for example, can be considered as a sequence of executable instructions stored in a computer readable medium, which can be executed by an instruction execution system, apparatus or device, such as a computer-based system, processor- based system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions, or a combination thereof. For the purposes of this specification, a "computer readable medium" can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The computer readable medium can specifically include the following, which are non-exhaustive list: electrical connection (electrical device having one or more wires), portable computer diskette (magnetic device), random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or Flash memory), optical fiber device, and portable compact disc read-only memory (CDROM). In addition, the computer readable medium can even be paper or other suitable medium upon which the program is printed, as the program can be electronically captured, for example, by optically scanning the paper or other suitable medium, then electronically converted into a form that can be edited, compiled, or interpreted, or otherwise processed in electronic form into an executable form suitable for use in the instruction execution system, apparatus or device.

[0129] It should be understood that parts of the present application can be implemented in hardware, software, firmware or a combination thereof. In the above embodiments, a plurality of steps or methods can be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. As in another embodiment, if implemented in hardware, any of the following technologies known in the art or their combination can be used: discrete logic circuit with logic gate circuit for implementing logic functions on data signals, application specific integrated circuit with suitable combination logic gate circuit, programmable gate array (PGA), field programmable gate array (FPGA), etc.

[0130] Those skilled in the art of the present technology can understand that all or part of the steps carried out by the above-mentioned embodiment method can be completed by a program instructing the relevant hardware, and the program can be stored in a computer readable storage medium. When the program is executed, it includes one of the steps of the method embodiment or a combination thereof.

[0131] In addition, each of the functional units in the various embodiments of the present application can be integrated in one processing module, or each of the units can be physically present separately, or two or more units can be integrated in one module. The integrated module can be implemented in the form of hardware or in the form of a software functional module. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer readable storage medium.

[0132] The storage medium mentioned above can be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. A method of generating a finite element model of a building component based on point cloud data, characterized by, The method comprises the following steps: obtaining original point cloud data of a building component, and obtaining a plurality of region point cloud data and a plurality of cross-section point cloud data according to the original point cloud data, wherein the plurality of region point cloud data respectively belong to a plurality of different plate members; obtaining point cloud data of each plate member region in each cross section according to the plurality of region point cloud data and the plurality of cross-section point cloud data, and fitting and segmenting a geometric model matched with the shape of each plate member in each cross section according to the point cloud data of each plate member region in each cross section, comprising: obtaining point cloud data respectively belonging to each plate member region in each cross section by taking the intersection of the plurality of region point cloud data and the plurality of cross-section point cloud data; fitting and segmenting a geometric model matched with the shape of each plate member in each cross section by a segmentation algorithm according to the point cloud data of each plate member region in each cross section, to obtain a geometric model corresponding to the point cloud data of each plate member region in each cross section; and when the point cloud data of each plate member region in each cross section only contains a single line, forming a double-line geometric model according to a preset thickness offset single line; obtaining an average geometric model of a plurality of plate members according to the geometric model matched with the shape of each plate member in each cross section, laying out grid points according to the average geometric model of the plurality of plate members, and stretching to obtain a standard finite element model; calculating an initial defect value of the building component according to the geometric model and the standard finite element model, and adding the initial defect value to the standard finite element model to obtain a finite element model of the building component.

2. The method of claim 1, wherein, The method of obtaining a plurality of region point cloud data and a plurality of cross-section point cloud data according to the original point cloud data comprises: selecting an initial end cross section plane of the original point cloud data, wherein the initial end cross section plane comprises a first cross section plane and a second cross section plane; taking point cloud data between the first cross section plane and the second cross section plane as sub-point cloud data, and obtaining a plurality of region point cloud data according to the sub-point cloud data; obtaining a plurality of cross sections between the first cross section plane and the second cross section plane, and obtaining a plurality of cross-section point cloud data according to the sub-point cloud data.

3. The method of claim 1, wherein, Before obtaining an average geometric model of a plurality of plate members according to the geometric model matched with the shape of each plate member in each cross section, the method comprises: connecting the centroid of the geometric model of the first cross section plane and the centroid of the corresponding geometric model of the second cross section plane; if the included angle between the centroid connecting line and the axis is greater than a first preset threshold, taking the centroid connecting line as a new axis, reselecting the first cross section plane and the second cross section plane, and repeating the above steps until the iteration number is greater than a second preset threshold and / or the included angle between the centroid connecting line and the axis is less than or equal to the first preset threshold.

4. The method of claim 1, wherein, The method of obtaining an average geometric model of a plurality of plate members according to the geometric model matched with the shape of each plate member in each cross section comprises: obtaining an average geometric model of a plurality of plate members according to a plurality of plate member regions corresponding geometric models; wherein a plurality of mathematical expressions of the same plate member region are obtained by extracting mathematical expressions from a plurality of geometric models respectively belonging to the same plate member region, and an average geometric model of the plate member is obtained by taking the average value of the parameters of the plurality of mathematical expressions.

5. The method of claim 1, wherein, The grid points are arranged and stretched according to the average geometric model of the plurality of plate members, and a standard finite element model is obtained, comprising: selecting a middle parallel line of the average geometric model of the plurality of plate members to obtain a plurality of average single-line models; calculating an actual arrangement grid size according to a preset arrangement grid size and a length of the line in the plurality of average single-line models, and arranging grid points according to the actual arrangement size; calculating the intersection points of the plurality of average single-line models in pairs, and adjusting the grid points according to the intersection point positions; calculating a stretching size according to the preset arrangement grid size and the axis length, and stretching the adjusted grid points along the axis direction according to the stretching size to obtain a standard finite element model.

6. The method of claim 1, wherein, The initial defect value of the building component is calculated according to the geometric model and the standard finite element model, comprising: selecting a middle parallel line of the plurality of geometric models to obtain a plurality of single-line models; calculating the local deviation of the grid points of the standard finite element model from the plurality of single-line models; calculating the coordinate difference between the plurality of single-line models and the average single-line model of each plate member as the overall deviation; obtaining the initial defect value of the grid points of the building component according to the local deviation and the overall deviation.

7. The method of claim 6, wherein, The local deviation of the grid points of the standard finite element model from the plurality of single-line models is calculated, comprising: obtaining point cloud data corresponding to a double line of the plurality of geometric models; orthogonal projecting the point cloud data onto the corresponding geometric model to obtain the parameter value and the local coordinate deviation of the point cloud data; orthogonal projecting the grid points of the standard finite element model onto the plurality of single-line models to obtain the parameter value of the grid points, and using a smoothing interpolation method to obtain the local deviation corresponding to the parameter value of the grid points according to the parameter value and the local coordinate deviation of the point cloud data.

8. A device for generating finite element models of building components based on point cloud data, characterized in that, comprising: an acquisition module configured to acquire original point cloud data of a building component, and obtain a plurality of regional point cloud data and a plurality of cross-sectional point cloud data according to the original point cloud data, wherein the plurality of regional point cloud data respectively belong to a plurality of different plate members; a geometric model acquisition module configured to obtain point cloud data of each plate member region in each cross section according to the plurality of regional point cloud data and the plurality of cross-sectional point cloud data, and fit and segment a geometric model matched with the shape of each plate member in each cross section according to the point cloud data of each plate member region in each cross section, comprising: obtaining point cloud data belonging to each plate member region in each cross section by taking the intersection of the plurality of regional point cloud data and the plurality of cross-sectional point cloud data; fitting and segmenting a geometric model matched with the shape of each plate member in each cross section by a segmentation algorithm according to the point cloud data of each plate member region in each cross section to obtain a geometric model corresponding to the point cloud data of each plate member region in each cross section; wherein when the point cloud data of each plate member region in each cross section only contains a single line, a double-line geometric model is formed according to a preset thickness offset single line; a standard finite element model obtaining module, configured to obtain an average geometric model of the plurality of plates according to the geometric model matched with the shape of each plate in each section, and obtain a standard finite element model by arranging grid points and stretching according to the average geometric model of the plurality of plates; a finite element model obtaining module, configured to calculate an initial defect value of the building component according to the geometric model and the standard finite element model, and obtain a finite element model of the building component by adding the initial defect value to the standard finite element model.

9. A non-transitory computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program, when executed by a processor, implements the method of any one of claims 1-7.

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