Method for installing a cable-membrane structure

Abstract

The application provides a cable membrane structure installation control method, which comprises the following steps: generating a digital model corresponding to a cable membrane structure, wherein the digital model comprises a BIM model and a corresponding design point cloud model; preliminarily installing the cable membrane structure according to the BIM model; performing three-dimensional laser scanning on the preliminarily installed cable membrane structure, and obtaining a measured point cloud model according to the scanning result; determining installation error data of the preliminarily installed cable membrane structure according to the design point cloud model and the measured point cloud model; and performing installation adjustment on the preliminarily installed cable membrane structure according to the installation error data. The application has the beneficial effect of realizing control of the precision of the cable membrane structure during installation, effectively improving the installation precision and installation efficiency of the cable membrane structure.

Description

Technical Field

[0001] This invention relates to the field of building information technology, and more specifically, to a method for controlling the installation of cable-membrane structures. Background Technology

[0002] Cable-membrane structures, such as prestressed cable-membrane structures, rely on the tensile stress of the membrane itself, along with support rods and cables, to form a structural system. They are particularly suitable for constructing roofs of buildings with curved surfaces, such as sports and entertainment venues, restaurants, and other public spaces with high population density. To ensure the safety of personnel, the installation precision of cable-membrane structures is crucial.

[0003] Traditional methods for controlling the installation accuracy of prestressed cable-membrane structures, such as leveling and triangulation, are time-consuming and labor-intensive, and difficult to measure data in narrow construction areas. In particular, for complex and large-scale layered cable-membrane structures, traditional testing methods are difficult to comprehensively and accurately measure the dimensional deviations of the installed cable-membrane structure, which makes it very difficult to adjust the components to be installed and makes it difficult to ensure the efficiency and accuracy of cable-membrane structure installation. Summary of the Invention

[0004] The problem addressed by this invention is how to improve the installation accuracy and efficiency of cable membrane structures.

[0005] To address the above problems, this invention provides a method for controlling the installation of a cable membrane structure, comprising the following steps:

[0006] Generate a digital model corresponding to the cable membrane structure, wherein the digital model includes a BIM model and a corresponding design point cloud model;

[0007] The cable-membrane structure is initially installed based on the BIM model;

[0008] A three-dimensional laser scan was performed on the initially installed cable-membrane structure, and a measured point cloud model was obtained based on the scan results;

[0009] The installation error data of the initially installed cable membrane structure are determined based on the design point cloud model and the measured point cloud model.

[0010] The cable membrane structure was initially installed and adjusted based on the installation error data.

[0011] Thus, a digital model of the cable membrane structure, i.e., a BIM model, is constructed by using the digital twinning technology, and a design point cloud model is generated based on the BIM model. Then, the cable membrane structure is preliminarily installed according to the digital model. The digital twinning has typical characteristics such as precise mapping, virtual-real interaction, and intelligent intervention, and can establish a digital model accurately reflecting the construction state, thereby providing an intelligent solution for the precision control of the structure installation. The point cloud data of the preliminarily installed cable membrane structure is acquired by using the three-dimensional laser scanning, and a measured point cloud model is constructed, so as to realize the intelligent collection of the position of the cable membrane structure during the installation process, save time and effort, and reduce the production cost. The measured point cloud model can be used to monitor whether the installed cable membrane structure is different from the design digital model, or whether the installation angle and position are accurate, so that the construction personnel can timely find and handle problems. The installation error data of the preliminarily installed cable membrane structure, such as distance error and torsion error, can be determined by comparing the design point cloud model with the measured point cloud model, so as to guide the construction personnel to adjust the preliminarily installed cable membrane structure, thereby improving the installation precision of the cable membrane structure. Meanwhile, the digital twinning and the three-dimensional scanning are combined to realize the intelligent installation and precision control of the cable membrane structure, and the installation efficiency and accuracy are improved.

[0012] Optionally, the preliminarily installing the cable membrane structure according to the BIM model comprises:

[0013] Acquiring three-dimensional coordinates corresponding to the members of the cable membrane structure in the BIM model.

[0014] Measuring and setting by using an infrared laser positioner, determining the spatial positions of the members of the cable membrane structure according to the measuring and setting results and the three-dimensional coordinates, and installing the cable membrane structure according to the spatial positions.

[0015] Thus, the spatial positions of the members of the cable membrane structure in the construction site are determined according to the three-dimensional coordinates in the BIM model and the measuring and setting results of the infrared laser positioner, and then the members are installed according to the determined spatial positions to obtain the preliminarily installed cable membrane structure, thereby improving the accuracy of the installation design of the cable membrane structure and helping to construct a standardized cable membrane structure. Meanwhile, the infrared laser positioner with high precision is used for measuring and setting, which can effectively improve the installation accuracy of the cable membrane structure and improve the installation efficiency.

[0016] Optionally, the infrared laser positioner comprises a base station and a remote receiver, and the measuring and setting by using the infrared laser positioner comprises:

[0017] The base station located at a calibration position emits two rotating scanning lasers and one synchronous pulse laser to the members of the cable membrane structure.

[0018] The rotating scanning laser and the synchronous pulse laser are received by the remote receiver located at the member of the cable membrane structure, and the relative angle and distance between the base station and the remote receiver are determined.

[0019] Thus, the base station transmits the scanning laser and the synchronous pulse laser, the remote receiver receives the scanning laser information and the synchronous pulse laser information, the relative angle and distance between the base station and the remote receiver are calculated and obtained, the surveying and setting of the cable membrane structure construction site are realized, the physical installation of the cable membrane structure is assisted, and the accuracy of the installation of the cable membrane structure is improved.

[0020] Optionally, the three-dimensional laser scanning of the preliminarily installed cable membrane structure and the obtaining of the measured point cloud model according to the scanning result include:

[0021] A three-dimensional laser scanning scheme is determined, wherein the cable membrane structure is scanned according to the three-dimensional laser scanning scheme, and the three-dimensional laser scanning scheme includes three-dimensional laser scanner site arrangement, scanning path selection, and target ball arrangement.

[0022] Based on the three-dimensional laser scanning scheme, the measured point cloud data corresponding to each member of the cable membrane structure is obtained.

[0023] The measured point cloud model is generated according to the measured point cloud data.

[0024] Thus, a corresponding three-dimensional laser scanning scheme is formulated according to the actual situation of the construction site, the three-dimensional laser scanner and the target ball are arranged according to the scheme, the initially installed cable membrane structure is scanned to obtain the measured point cloud model of each component, the digital collection of the installation position in the installation process of the cable membrane structure is effectively realized, and the intelligentization of the installation precision control of the cable membrane structure is improved.

[0025] Optionally, the determination process of the three-dimensional laser scanner site arrangement includes: determining an optimal scanning site according to a greedy algorithm with a weight value, taking the three-dimensional coordinates corresponding to the members of the cable membrane structure in the BIM model as a basis, searching for the current optimal scanning site within a preset threshold range through the optimal scanning site of the last station as a starting point until the scanning target is completely covered.

[0026] The determination process of the scanning path selection includes: taking the shortest scanning path as a target, optimizing the optimal scanning site set through a path planning A* algorithm, and determining the optimal scanning path.

[0027] The determination process of the target ball arrangement includes: discretely arranging the target balls in the intersection of the visible areas of adjacent scanning sites to ensure that the point cloud data of adjacent sites has at least three non-collinear target balls.

[0028] Therefore, the optimal scanning station is determined by using the weighted greedy algorithm, the target ball position is determined, and the most scanning path is obtained by using the path planning A* algorithm, so that the three-dimensional laser scanning scheme for different construction sites and cable membrane structures is effectively implemented, and the measured point cloud data of the cable membrane structure is accurately obtained.

[0029] Optionally, the installation error data of the preliminarily installed cable membrane structure is determined according to the design point cloud model and the measured point cloud model, and the installation error data of the preliminarily installed cable membrane structure includes:

[0030] The design point cloud model and the measured point cloud model are coarsely aligned by using principal component analysis.

[0031] The nearest neighbor points of the design point cloud model and the measured point cloud model after coarse alignment are obtained by using the iterative nearest neighbor algorithm, and the design point cloud model and the measured point cloud model are accurately aligned according to the nearest neighbor points.

[0032] Therefore, the complete measured point cloud model and the design point cloud model are coarsely aligned and accurately aligned by using the principal component analysis and the iterative nearest neighbor algorithm, respectively, so that the accuracy of the alignment of the measured point cloud model and the design point cloud model is improved, and a foundation is laid for subsequent detection and control of the precision of the cable membrane structure.

[0033] Optionally, the installation error data of the preliminarily installed cable membrane structure is determined according to the design point cloud model and the measured point cloud model, and the installation error data of the preliminarily installed cable membrane structure includes:

[0034] The cable head installation error, the membrane structure installation distance error and the membrane structure installation surface torsion error of the preliminarily installed cable membrane structure are determined according to the design point cloud model and the measured point cloud model after accurate alignment.

[0035] Therefore, when the cable membrane structure is installed, the installation of the cable head, the installation of the membrane structure and the membrane structure surface torsion degree are crucial to the stability of the cable membrane structure, so that the overall installation precision of the cable membrane structure is adjusted by detecting the errors of the cable head installation position, the membrane structure installation position and the membrane structure surface torsion degree.

[0036] Optionally, the determination process of the cable head installation error includes:

[0037] The theoretical middle hole center coordinates of the cable head are determined according to the BIM model, and the actual middle hole center coordinates of the cable head are determined according to the measured point cloud model.

[0038] The distance deviation value between the actual middle hole center coordinates of the cable head and the theoretical middle hole center coordinates of the cable head is determined as the cable head installation error.

[0039] Thus, by acquiring the theoretical middle hole center coordinates and the actual middle hole center coordinates of the cable head in the BIM model and the measured point cloud model, the installation error of the cable head is calculated, the construction personnel can intuitively understand the error size, and the initial cable membrane structure is adjusted, and the control of the installation precision of the cable head is realized.

[0040] Optionally, the determination process of the membrane structure installation distance error comprises:

[0041] The K-neighbor searching algorithm is adopted to acquire the data point with the maximum distance error in the design point cloud model and the measured point cloud model as the feature point.

[0042] The distance error of the feature point and the corresponding data point in the design point cloud model is determined.

[0043] Thus, the point with the maximum distance error is acquired by adopting the K-neighbor searching algorithm, and then the membrane structure installation distance error in the design point cloud model and the measured point cloud model is acquired, the construction personnel can intuitively understand the error size, and the initial cable membrane structure is adjusted, and the control of the installation precision of the membrane structure is realized.

[0044] Optionally, the determination process of the membrane structure installation surface twist error comprises:

[0045] The least square method is used to fit the surface of each data point and the adjacent multiple data points in the design point cloud model, and the least square method is used to fit the surface of each data point and the adjacent multiple data points in the measured point cloud model, and the best fitting planes are determined respectively.

[0046] The surface twist error value is determined according to the included angle of the best fitting plane of the design point cloud model and the best fitting plane of the measured point cloud model.

[0047] Thus, the fitting planes and the included angles of multiple data points are acquired first, and then the surface twist error value in the design point cloud model and the measured point cloud model is acquired, the construction personnel can intuitively understand the error size, and the initial cable membrane structure is adjusted, and the control of the installation precision of the surface twist degree of the membrane structure is realized. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 It is a flowchart of the cable membrane structure installation control method of the embodiment of the present application. DETAILED DESCRIPTION

[0049] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings.

[0050] Referring to Figure 1 The cable membrane structure installation control method of the embodiment of the present application comprises:

[0051] Step S1, generating a digital model corresponding to the cable membrane structure, wherein the digital model comprises a BIM model and a corresponding design point cloud model.

[0052] Specifically, an initial BIM model is established according to collected cable membrane structure design materials, actual cable membrane engineering and initial data, and relevant materials and research data of the construction process of the cable membrane structure are collected, and finally a high-precision BIM model, i.e., a complete information building three-dimensional model, is established, so as to simulate and optimize the construction process of the building engineering. The BIM model is converted into a design point cloud model corresponding to the cable membrane structure by using a data processing software, so as to facilitate subsequent calculation and adjustment of the precision of the cable membrane structure.

[0053] Step S2, preliminarily installing the cable membrane structure according to the BIM model.

[0054] Specifically, the coordinate information of the BIM model is obtained, and a surveying and setting device is used to survey the construction site to determine the installation positions of the components of the cable membrane structure in the construction site, and the cable membrane structure is preliminarily installed.

[0055] Step S3, three-dimensional laser scanning is performed on the preliminarily installed cable membrane structure, and a measured point cloud model is obtained according to the scanning result.

[0056] Specifically, the best three-dimensional laser scanner arrangement position is selected, so that the scanning range can cover the target within the specified range, and the integrity of the target point cloud data is ensured. The three-dimensional laser scanner is installed according to the best arrangement position, three-dimensional laser scanning is performed on the components of the cable membrane structure, point cloud data of each component is obtained, and the measured point cloud model is obtained by splicing the corresponding measured point cloud data of each structure. The three-dimensional coordinates of the three-dimensional laser scanner station are taken as control points, the measured point cloud data obtained by multi-station scanning is registered into a unified coordinate system based on a target ball. In the splicing process, if a certain station is designated as a master station, the coordinate systems of other stations are rotated and translated by using the same point between stations to determine the constraint condition, and after splicing is completed, the complete measured point cloud model of the entire project is obtained, which is used for subsequent comparison with the complete design point cloud model.

[0057] Step S4, determining installation error data of the preliminarily installed cable membrane structure according to the design point cloud model and each measured point cloud model.

[0058] Specifically, when the cable membrane structure is scanned in three dimensions, due to the influence of factors such as lens distortion, light during measurement, geographical environment, etc., the obtained measured point cloud data may have large errors, therefore, before obtaining the error data of the designed point cloud model and the measured point cloud model, the measured point cloud data is pre-processed, such as abnormal point processing, denoising processing and uniform sampling, to avoid impurities in the data reducing the accuracy of the error data, and to obtain accurate measured point cloud data to improve the accuracy of subsequent cable membrane structure installation precision control. Then, the point cloud design data and the measured point cloud data are converted and unified, and the complete measured point cloud model and the designed point cloud model are coarsely aligned and accurately aligned to realize the alignment of the measured point cloud model and the designed point cloud model. Based on the designed point cloud model, the measured point cloud model components such as cable head, membrane structure, etc. are compared and calculated to determine the installation error data of the preliminary installed cable membrane structure.

[0059] Step S5, according to the installation error data, the preliminary installed cable membrane structure is adjusted.

[0060] In this embodiment, the digital twin technology is applied to construct the digital model of the cable membrane structure, i.e. the BIM model and the designed point cloud model generated therefrom, and then the cable membrane structure is preliminarily installed according to the digital model. The digital twin has typical characteristics such as precise mapping, virtual-real interaction, intelligent intervention, etc., and can establish a digital model accurately reflecting the construction state, providing an intelligent solution for structure installation precision control. The three-dimensional laser scanning is used to obtain the point cloud data of the preliminarily installed cable membrane structure, and the measured point cloud model is constructed to realize intelligent collection of the position of the cable membrane structure during installation, saving time and effort, and reducing production cost. The measured point cloud model can be used to monitor whether the installed cable membrane structure is different from the designed digital model, or whether the installation angle and position are accurate, so that the construction personnel can timely find problems and handle them. By comparing the designed point cloud model with the measured point cloud model, the installation error data of the preliminarily installed cable membrane structure can be determined, such as distance error and torsion error, which can guide the construction personnel to adjust the preliminarily installed cable membrane structure, improve the installation precision of the cable membrane structure, and realize the intelligent installation and precision control of the cable membrane structure by combining the digital twin with three-dimensional scanning, improving the installation efficiency and accuracy.

[0061] Optionally, the preliminary installation of the cable membrane structure according to the BIM model comprises:

[0062] Obtaining the three-dimensional coordinates corresponding to the components of the cable membrane structure in the BIM model.

[0063] The components of the cable membrane structure are determined according to the measurement results and the three-dimensional coordinates by using an infrared laser positioner for measurement, and the cable membrane structure is installed according to the spatial position.

[0064] Specifically, the three-dimensional coordinates of each component in the cable-membrane structure BIM model are acquired, and the construction site is tested by using an infrared laser positioner to acquire the surveying and setting results of the cable-membrane structure construction site, the spatial positions of each component of the cable-membrane structure are determined in combination with the three-dimensional coordinates of each component in the BIM model and the surveying and setting results, and the construction personnel performs preliminary installation of the cable-membrane structure according to the determined spatial positions. In the embodiment, the infrared laser positioner has a millimeter-level precision, which helps to acquire more accurate spatial positions of the cable-membrane structure, so as to improve the accuracy of the cable-membrane structure installation.

[0065] In the embodiment, the spatial positions of each component of the cable-membrane structure in the construction site are determined according to the three-dimensional coordinates in the BIM model and the surveying and setting results of the infrared laser positioner, and then the installation is performed according to the determined spatial positions to acquire the preliminary installation of the cable-membrane structure, which improves the accuracy of the installation design of the cable-membrane structure, helps to construct a standardized cable-membrane structure, and effectively increases the accuracy of the cable-membrane structure installation and improves the installation efficiency by using the infrared laser positioner with high precision for surveying and setting.

[0066] Optionally, the infrared laser positioner comprises a base station and a remote receiver; and the surveying and setting by the infrared laser positioner comprises:

[0067] The base station located at the calibration position emits two rotating scanning lasers and a synchronous pulse laser to the components of the cable-membrane structure.

[0068] The remote receiver located at the components of the cable-membrane structure receives the rotating scanning lasers and the synchronous pulse laser, and determines the relative angle and distance between the base station and the remote receiver.

[0069] Specifically, the best calibration position of the infrared laser positioner base station is selected according to the actual situation of the construction site, the base station is installed according to the best calibration position, and the remote receiver is installed at the position of each component of the preliminary installation of the cable-membrane structure. The base station emits two rotating scanning lasers and a synchronous pulse laser to the components of the cable-membrane structure installed with the remote receiver to form laser scanning coverage of the cable-membrane structure. The remote receiver installed at the component position receives the rotating scanning lasers and the synchronous pulse laser emitted by the base station, identifies the signal source according to the photoelectric pulse interval and rotation speed matching relationship, calculates the scanning rotation angle of the base station through the synchronous light-scan light phase relationship, calculates the distance between the base station and the remote receiver through the time and speed of the laser received by the remote receiver, and acquires the actual three-dimensional coordinates of each component of the cable-membrane structure, so as to complete the surveying and setting of the cable-membrane structure construction site and acquire the surveying and setting results.

[0070] In the embodiment, the base station transmits scanning laser and synchronous pulse laser, the remote receiver receives scanning laser information and synchronous pulse laser information, and the relative angle and distance between the base station and the remote receiver are calculated to realize the measurement and setting of the cable-membrane structure construction site, assist the physical installation of the cable-membrane structure, and improve the installation accuracy of the cable-membrane structure.

[0071] Optionally, the three-dimensional laser scanning of the preliminarily installed cable-membrane structure includes:

[0072] A three-dimensional laser scanning scheme is determined, wherein the cable-membrane structure is scanned according to the three-dimensional laser scanning scheme, and the three-dimensional laser scanning scheme includes three-dimensional laser scanner station arrangement, scanning path selection, and target ball arrangement.

[0073] Based on the three-dimensional laser scanning scheme, the measured point cloud data corresponding to each component of the cable-membrane structure is obtained.

[0074] The measured point cloud model is generated according to the measured point cloud data.

[0075] Specifically, when the initially installed cable-membrane structure is scanned, because of the complex structure, a three-dimensional laser scanning scheme conforming to the structure should be first formulated to make the scanning range cover the cable-membrane structure in the preset range, so that a relatively complete measured point cloud model can be obtained. The three-dimensional laser scanning scheme includes three-dimensional laser scanner station arrangement, scanning path selection, and target ball arrangement. The three-dimensional laser scanner and the target ball are arranged according to the three-dimensional laser scanning scheme, the cable-membrane structure is scanned by three-dimensional laser scanning, the measured point cloud data of each component of the cable-membrane structure is obtained, and the measured point cloud model corresponding to each component is generated.

[0076] In the embodiment, a corresponding three-dimensional laser scanning scheme is formulated according to the actual situation of the construction site, the three-dimensional laser scanner and the target ball are arranged according to the scheme, the initially installed cable-membrane structure is scanned to obtain the measured point cloud model of each component, the digital collection of the installation position in the installation process of the cable-membrane structure is effectively realized, and the intelligentization of the installation precision control of the cable-membrane structure is improved.

[0077] Optionally, the determination process of the three-dimensional laser scanner station arrangement includes: determining an optimal scanning station according to a greedy algorithm with a weight value, taking the three-dimensional coordinates corresponding to the components of the cable-membrane structure in the BIM model as the basis, searching for the current optimal scanning station within a preset threshold range from the optimal scanning station of the last station as the starting point, and until the scanning target is completely covered.

[0078] The determination process of the scanning path selection includes: taking the shortest scanning path as the target, optimizing the optimal scanning station set through the path planning A* algorithm, and determining the optimal scanning path.

[0079] The determination process of the target ball arrangement includes: by discretely arranging the target ball in the intersection of the adjacent scanning station visible areas, to ensure that the point cloud data of the adjacent stations has at least 3 non-collinear target balls.

[0080] Specifically, for the three-dimensional laser scanner station arrangement, three-dimensional coordinates of the BIM model are acquired, and based on the three-dimensional coordinates, the current optimal scanning station is searched within a preset threshold range starting from the optimal scanning point of the previous station until the scanning target within the specified range is completely covered, and the optimal scanning station is solved by using the greedy algorithm, and the three-dimensional laser scanner station is arranged at the optimal scanning station. In order to consider the integrity of the target point cloud data and the scanning time, it is set that 95% of the targets within the specified range are scanned as the termination condition of the scanning scheme optimization. For the arrangement of the target ball, 1.5 times of the scanning distance is taken when three-dimensional laser scanning is performed, so as to ensure that the target ball has sufficient arrangement space, and the target ball is discretely arranged in the intersection of the adjacent scanning station visible areas as much as possible, to ensure that the point cloud data of the adjacent stations has at least a certain number of non-collinear target balls, for example, 3. The shortest scanning path is taken as the target, and the path planning A* algorithm is used to optimize the path of the optimal scanning station set to determine the optimal scanning path.

[0081] In the embodiment, the weighted greedy algorithm is used to determine the optimal scanning station, and the target ball position is determined, and the path planning A* algorithm is further used to obtain the optimal scanning path, so as to effectively realize the formulation of the three-dimensional laser scanning scheme for different construction sites and cable membrane structures, and accurately obtain the measured point cloud data of the cable membrane structure.

[0082] Optionally, the installation error data of the cable membrane structure preliminarily installed according to the design point cloud model and the measured point cloud model includes:

[0083] The design point cloud model and the measured point cloud model are coarsely aligned by using the principal component analysis method.

[0084] The nearest neighbor points of the design point cloud model and the measured point cloud model after coarse alignment are obtained by using the iterative nearest neighbor algorithm, and the design point cloud model and the measured point cloud model are finely aligned according to the nearest neighbor points.

[0085] Specifically, firstly, the principal component analysis method is used to perform initial alignment, i.e. coarse alignment, on the spliced measured point cloud model and the design point cloud model, so that the center and the main shaft of the measured point cloud model are aligned with the design point cloud model. Secondly, the measured point cloud model is compared with the design point cloud model, the iterative nearest neighbor algorithm is used to obtain the nearest neighbor data points of each data point in the measured point cloud model and the design point cloud model, the distance between the two nearest neighbor data points is obtained, and a distance preset value is set. When the distance between the two nearest neighbor data points is less than the distance preset value, it is determined that the data point is a corresponding point, and the two data points are aligned to realize fine alignment of the design point cloud model and the measured point cloud model.

[0086] In this embodiment, the principal component analysis method and the iterative nearest neighbor algorithm are used to perform coarse alignment and fine alignment on the complete measured point cloud model and the design point cloud model, respectively, thereby improving the accuracy of the alignment of the measured point cloud model and the design point cloud model and laying a foundation for subsequent detection and control of the precision of the cable membrane structure.

[0087] Optionally, the installation error data of the preliminarily installed cable membrane structure determined according to the design point cloud model and the measured point cloud model further includes:

[0088] The cable head installation error, the membrane structure installation distance error and the membrane structure installation surface torsion error of the preliminarily installed cable membrane structure are determined according to the fine-aligned design point cloud model and the fine-aligned measured point cloud model.

[0089] Specifically, after the alignment of the measured point cloud model and the design point cloud model, the corresponding point cloud data are compared. The installation of the cable head, the installation of the membrane structure and the membrane structure surface torsion degree play an important role in the installation of the cable membrane structure. Therefore, in this embodiment, the error detection is performed on the installation position of the cable head, the installation position of the membrane structure and the membrane structure surface torsion degree, the error information of the installation position of the cable head, the installation position of the membrane structure and the membrane structure surface torsion degree in the measured point cloud model and the installation position of the cable head, the installation position of the membrane structure and the membrane structure surface torsion degree in the design point cloud model is obtained, and the error information can be displayed in the form of a color-coded difference map.

[0090] In this embodiment, during the installation of the cable membrane structure, the installation of the cable head, the installation of the membrane structure and the membrane structure surface torsion degree are crucial to the stability of the cable membrane structure. Therefore, the error detection is performed on the installation position of the cable head, the installation position of the membrane structure and the membrane structure surface torsion degree to realize the adjustment of the overall installation precision of the cable membrane structure. Meanwhile, the error result is displayed in the form of a color-coded difference map, which can more intuitively display the error size and prompt the construction personnel to adjust the cable membrane structure.

[0091] Optionally, the determination process of the cable head installation error includes:

[0092] The theoretical middle hole center coordinates of the cable head are determined according to the BIM model, and the actual middle hole center coordinates of the cable head are determined according to the measured point cloud model.

[0093] The distance deviation value of the actual middle hole center coordinates of the cable head and the theoretical middle hole center coordinates is determined as the installation error of the cable head based on the design point cloud model.

[0094] Specifically, the installation error of the cable head seriously affects the installation precision of the cable membrane structure. In the embodiment, the point cloud data of the edge of the cable head in the BIM model is first obtained, the theoretical middle hole center coordinates (x m , y m , z m ) are calculated and obtained according to the point cloud data of the edge of the cable head, the point cloud data of the edge of the cable head is obtained through the measured point cloud model, and the actual middle hole center coordinates (x d , y d , z d ) are calculated and obtained. More specifically, since the point cloud data corresponds to an entity feature, the contour of the cable head can be first determined through the point cloud data, and then the position of the center point, that is, the center coordinates, can be calculated and obtained according to the contour. The distance deviation value of the theoretical middle hole center coordinates (x m , y m , z m ) and the actual middle hole center coordinates (x d , y d , z d ) is calculated as the installation error of the cable head based on the theoretical middle hole center coordinates, and is displayed in a color-coded difference map. In addition, the theoretical middle hole center coordinates and the actual middle hole center coordinates of the cable head can be obtained by determining the geometric center point of the cable head.

[0095] In the embodiment, the installation error of the cable head is calculated by obtaining the theoretical middle hole center coordinates and the actual middle hole center coordinates of the cable head in the BIM model and the measured point cloud model, and the deviation value of the cable head is displayed in a color-coded difference map. Construction personnel can intuitively understand the error size, and adjust the initial cable membrane structure, thereby realizing the control of the installation precision of the cable head.

[0096] Optionally, the determination process of the membrane structure installation distance error comprises:

[0097] The data point with the maximum distance error in the design point cloud model and the measured point cloud model is obtained as a feature point by using a K-neighbor search algorithm.

[0098] The distance error of the feature point and the corresponding data point in the design point cloud model is determined.

[0099] Specifically, the K-neighbor search algorithm is used to determine the point with the maximum distance error between the aligned measured point cloud model and the design point cloud model, and the point is listed as a surface boundary feature point. The film structure installation distance error β is calculated according to the distance error formula, and the distance error formula is represented as:

[0100] ,

[0101] where ΔX, ΔY, ΔZ are the differences between the measured point cloud coordinates and the corresponding point cloud design coordinates of the point with the maximum distance error. In addition, the direction of the vector from the feature point to the nearest data point and the direction of the point cloud main axis need to be compared. If the directions are the same, the film structure installation distance error β is positive, and if the directions are different, the film structure installation distance error β is negative, and the difference is displayed in a color-coded difference map.

[0102] In this embodiment, the K-neighbor search algorithm is used to obtain the point with the maximum distance error, and then the film structure installation distance error between the design point cloud model and the measured point cloud model is obtained, and the film structure installation distance error is displayed in a color-coded difference map. Construction personnel can intuitively understand the error size and adjust the initial cable membrane structure to achieve control of the installation precision of the membrane structure.

[0103] Optionally, the process of determining the film structure installation curved surface torsion error comprises:

[0104] Each data point in the design point cloud model and a plurality of adjacent data points are fitted using the least squares method to determine the best fitting plane, and each data point in the measured point cloud model and a plurality of adjacent data points are fitted using the least squares method to determine the best fitting plane.

[0105] The angle between the best fitting plane of the design point cloud model and the best fitting plane of the measured point cloud model is used to determine the curved surface torsion error value.

[0106] Specifically, the data points in each measured point cloud model and, for example, k data points in the vicinity thereof are fitted using the least squares method, and the quadratic surface formula is:

[0107] ,

[0108] where z represents the data point, x represents the horizontal coordinate of the data point, y represents the vertical coordinate of the data point, and a, b, and c represent constants. The data points in each design point cloud model and, for example, k data points in the vicinity thereof are fitted using the least squares method to determine the best fitting plane of the design point cloud model. The curved surface torsion error value is calculated according to the angle between the best fitting plane of the design point cloud model and the best fitting plane of the measured point cloud data, and the curved surface torsion error value is displayed in a color-coded difference map.

[0109] In the embodiment, firstly, the fitting plane and the included angle of the plurality of data points are obtained, and then the surface twist error values in the design point cloud model and the measured point cloud model are obtained, and the surface twist error values are displayed in a color-coded difference map, so that the construction personnel can intuitively understand the error size, and adjust the initial cable membrane structure, thereby realizing the control of the installation precision of the membrane structure surface twist degree.

[0110] Optionally, the cable membrane structure installation control method further comprises:

[0111] The adjusted cable membrane structure is subjected to three-dimensional laser scanning to obtain a corresponding point cloud model, and is subjected to alignment processing and precision calculation processing with the design point cloud model, until the error is less than an error setting value.

[0112] Specifically, the cable membrane structure adjusted through the above steps is obtained, and steps S3 to S5 are repeated to re-perform three-dimensional laser scanning and error calculation processing on the adjusted cable membrane structure, and the cable membrane structure is further adjusted until the cable head installation error, the membrane structure distance error and the surface twist error value are all less than the corresponding setting error value, at this time, the obtained cable membrane structure is the cable membrane structure meeting the precision requirement.

[0113] In the embodiment, the three-dimensional laser scanning and error processing are repeatedly performed on the cable membrane structure, the error between the entity cable membrane structure and the design model is continuously obtained, and the adjustment is performed according to the error until the error is less than the error setting value, the cable membrane structure meeting the precision requirement is obtained, the control of the precision of the cable membrane structure is realized, the point cloud data of the cable membrane structure obtained by three-dimensional laser scanning is used for precision calculation, the intelligent cable membrane structure installation process data is obtained, and the installation efficiency of the cable membrane structure is effectively improved.

[0114] Although the present application is disclosed as above, the protection scope of the present application is not limited to this. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application, and these changes and modifications will fall within the protection scope of the present application.

Claims

1. A method for controlling the installation of a cable-membrane structure, characterized in that, include: Generate a digital model corresponding to the cable membrane structure, wherein the digital model includes a BIM model and a corresponding design point cloud model; The cable-membrane structure is initially installed based on the BIM model; A three-dimensional laser scan was performed on the initially installed cable-membrane structure, and a measured point cloud model was obtained based on the scan results; The installation error data of the initially installed cable-membrane structure is determined based on the design point cloud model and the measured point cloud model. This determination includes: Principal component analysis was used to coarsely align the design point cloud model and the measured point cloud model. The nearest neighbor algorithm is used to obtain the nearest neighbor points of the coarsely aligned design point cloud model and the measured point cloud model, and the fine alignment of the design point cloud model and the measured point cloud model is performed based on the nearest neighbor points; The determination of the installation error data of the initially installed cable-membrane structure based on the design point cloud model and the measured point cloud model also includes: Based on the precisely aligned design point cloud model and the measured point cloud model, determine the cable head installation error, membrane structure installation distance error, and membrane structure installation surface torsion error of the initially installed cable-membrane structure; The cable membrane structure was initially installed and adjusted based on the installation error data.

2. The cable membrane structure installation control method according to claim 1, characterized in that, The preliminary installation of the cable-membrane structure based on the BIM model includes: Obtain the three-dimensional coordinates of the components corresponding to the cable-membrane structure in the BIM model; The spatial positions of the components of the cable-membrane structure are determined by measuring the results using an infrared laser positioning instrument and the three-dimensional coordinates, and the cable-membrane structure is installed according to the spatial positions.

3. The cable membrane structure installation control method according to claim 2, characterized in that, The infrared laser positioning device includes a base station and a remote receiver; the measurement and positioning via the infrared laser positioning device includes: Two rotating scanning laser beams and one synchronous pulse laser beam are emitted from the base station located at the calibrated position toward the components of the cable membrane structure. The rotating scanning laser and the synchronous pulsed laser are received by the remote receiver located at a component of the cable membrane structure, and the relative angle and distance between the base station and the remote receiver are determined.

4. The cable membrane structure installation control method according to claim 1, characterized in that, The step of performing a three-dimensional laser scan on the initially installed cable-membrane structure and obtaining a measured point cloud model based on the scan results includes: A three-dimensional laser scanning scheme is determined, wherein the cable membrane structure is scanned according to the three-dimensional laser scanning scheme, which includes the layout of three-dimensional laser scanner stations, the selection of scanning paths, and the layout of target spheres; Based on the three-dimensional laser scanning scheme, the measured point cloud data corresponding to each component of the cable membrane structure are obtained; The measured point cloud model is generated based on the measured point cloud data.

5. The cable-membrane structure installation control method according to claim 4, characterized in that, The process of determining the layout of the three-dimensional laser scanner sites includes: determining the optimal scanning site according to a weighted greedy algorithm, using the three-dimensional coordinates of the components corresponding to the cable membrane structure in the BIM model as the basis, and searching for the current optimal scanning site within a preset threshold range, starting from the optimal scanning site of the previous station, until the scanning target is completely covered. The process of determining the scanning path selection includes: optimizing the optimal scanning site set using the path planning A* algorithm with the goal of minimizing the scanning path; The process of determining the target ball arrangement includes: discretely arranging the target balls within the intersection of the visible areas of adjacent scanning stations to ensure that the point cloud data of adjacent stations have at least 3 non-collinear target balls.

6. The cable membrane structure installation control method according to claim 1, characterized in that, The process for determining the cable head installation error includes: The theoretical center coordinates of the intermediate hole of the cable head are determined based on the BIM model, and the actual center coordinates of the intermediate hole of the cable head are determined based on the measured point cloud model. Based on the design point cloud model, the distance deviation between the actual center coordinates of the intermediate hole and the theoretical center coordinates of the intermediate hole of the cable head is determined, and this deviation is taken as the installation error of the cable head.

7. The cable membrane structure installation control method according to claim 1, characterized in that, The process for determining the installation distance error of the membrane structure includes: The K-nearest neighbor search algorithm is used to obtain the data point with the largest distance error between the designed point cloud model and the measured point cloud model as the feature point; Determine the distance error between the feature point and the corresponding data point in the design point cloud model.

8. The cable membrane structure installation control method according to claim 1, characterized in that, The process for determining the torsional error of the membrane structure installation surface includes: The least squares method is used to fit each data point in the design point cloud model with multiple neighboring data points, and the least squares method is used to fit each data point in the measured point cloud model with multiple neighboring data points to determine the best fitting plane. The surface torsion error value is determined based on the angle between the best-fit plane of the designed point cloud model and the best-fit plane of the measured point cloud model.

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