Intelligent spatial positioning method for curved steel structure roof based on GNSS (Global Navigation Satellite System)

Abstract

The invention belongs to the field of civil engineering intelligent construction, and relates to a curved steel structure roof intelligent space positioning method based on GNSS. According to the method, a three-dimensional laser scanning technology, a GNSS technology and a building information model (BIM) are combined, and accurate monitoring and dynamic adjustment of the curved steel structure roof space positioning process are achieved. According to the method, manual operation errors can be effectively reduced, the construction precision is improved, and the method has high adaptability and real-time performance and is suitable for space positioning of intelligent construction of a complex curved steel structure roof. Through the method, the spatial positioning precision of the steel member can be remarkably improved, and reference is provided for intelligent construction of similar projects.

Description

Technical Field

[0001] The invention belongs to the field of intelligent construction of civil engineering and relates to an intelligent spatial positioning method for a curved steel structure roof based on GNSS. Background Art

[0002] With the rapid development of modern construction technology, especially the widespread application of steel structures and space structures, steel structure roofs have gradually become an important structural form in architectural design; due to the diverse shapes and complex curves of steel structure roofs, especially in large-scale construction projects, the accurate positioning and construction accuracy of the roof structure are crucial to building quality and safety.

[0003] At present, the methods for positioning steel structure roofs are mostly concentrated on traditional manual measurement or ground control point systems. These methods usually have the following shortcomings: low measurement accuracy, large workload, low construction efficiency and susceptibility to interference from environmental factors. Therefore, a GNSS-based intelligent spatial positioning method for curved steel structure roofs is proposed. It can combine modern positioning technology with intelligent means to improve the positioning accuracy during roof construction, reduce human intervention, and effectively improve construction efficiency and safety. Summary of the invention

[0004] Aiming at the measurement and positioning difficulties in the installation process of a curved steel structure roof, the present invention provides a GNSS-based intelligent spatial positioning method for a curved steel structure roof.

[0005] The present invention is achieved through the following technical solutions:

[0006] S1, collecting 3D laser scanning point cloud field data: using the method of arranging base station scanners, using 3D laser scanning technology to collect 3D points of the processed curved steel structure roof in all directions, and obtaining the original point cloud model data of the curved steel structure roof;

[0007] S2, processing point cloud model data: removing invalid point clouds through point cloud stitching, point cloud overall registration, point cloud cutting, and point cloud denoising;

[0008] S3, fitting the curved surface of the curved steel structure roof and BIM modeling: according to the processed point cloud data, the third-order parametric equation is used to reconstruct the surface, the three-dimensional BIM model of the curved steel structure roof is established using Revit software, and the control points are calculated according to the node vector;

[0009] S31, the processed point cloud data set is recorded as R i，j (i=0,1,2,...,r;j=0,1,2,...,s), which are distributed on s+1 different sections, each section contains r+1 data points, and two parameter directions are specified: x and z, where the x direction is the plane direction of the site and the z direction is the elevation direction of the site;

[0010] S32, construct the surface equation group P(x, z), see formula (1):

[0011]

[0012] Where, d i，j is the feature point of the point cloud dataset, N i，l (x), N j，k (z) are plane curves in the x and z directions respectively;

[0013] S33, interpolate the surface equation group P(x, z) in the x direction to generate r cross-sectional interpolation curves with z as a parameter, and find the control vertices of the cross-sectional curves See formula (2):

[0014]

[0015] Where, d i，r is the interpolation point in the x direction, N(z r ) is the cross-section interpolation curve equation;

[0016] S34, Control Vertices of Section Curves That is, the points to be measured on the curved steel structure roof; a three-dimensional BIM model of the curved steel structure roof is established in the software, and the coordinates of the points to be measured are imported;

[0017] S4, GNSS control point layout and measurement error calculation: Use GNSS technology to measure the points to be measured in the BIM model to the construction site, deploy GNSS measuring instruments at the measurement reference points, monitor satellite data for no less than 45 minutes, and import the data into the data processing software to extract the baseline vector after monitoring. According to the extracted baseline vector, a GNSS baseline vector network is constructed to automatically derive the theoretical coordinates of the points to be measured; place the target prism at the point to be measured on the curved steel structure roof, use the ATR function of the measurement robot to automatically search for the target prism, and calculate the actual coordinates of the points to be measured according to formula (3):

[0018]

[0019] Among them, S is the straight-line distance between the reference point and the point to be measured, X P , Y P , Z P They are the coordinate components of the point to be measured in the x, y, and z directions respectively. M , Y M 、z M are the coordinate components of the reference point in the x, y, and z directions respectively, α is the horizontal angle between the reference point and the point to be measured, β is the vertical angle between the reference point and the point to be measured, and θ is the azimuth of the line connecting the reference point and the point to be measured;

[0020] Use formula (4) to calculate the error term of the coordinates of the measured point

[0021]

[0022] Among them, m Δα 、m αβ are the error values ​​of the points to be measured, ρ is the theoretical coordinate value of the points to be measured, m s To measure the robot's distance measurement accuracy;

[0023] S5, check the error value: check whether the error value of the measured point is within the allowable range.

[0024] Beneficial effects of the present invention: In view of the difficulty in spatial positioning of curved steel structure roof installation, the present invention proposes a GNSS-based intelligent spatial positioning method for curved steel structure roof. The method combines GNSS technology, three-dimensional laser scanning technology and building information model (BIM) to achieve precise monitoring and dynamic adjustment of the spatial positioning of curved steel structure roof, providing an advanced method for the installation positioning of curved steel structure roof. The method can significantly ensure the quality of the project, improve construction efficiency and shorten the construction period. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a flow chart of an embodiment of the present invention.

[0026] Figure 2 It is a schematic diagram of the site layout and the curved steel structure roof of an embodiment of the present invention; in the figure: 1 is a main beam of the curved steel structure roof, 2 is a secondary beam of the curved steel structure roof, 3 is a positioning prism, 4 is a GNSS measurement base station, and 5 is a measurement robot.

[0027] Figure 3 It is a measurement principle diagram of an embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0029] Example: Figure 2 The present invention provides a GNSS-based intelligent spatial positioning method process for a curved steel structure roof.

[0030] S1, S2: Use base station scanners to collect 3D points of the processed curved steel structure roof in all directions using 3D laser scanning technology to obtain the original point cloud model data of the curved steel structure roof; remove invalid point clouds through point cloud stitching, point cloud overall registration, point cloud cutting, and point cloud denoising; this embodiment takes 13 3D point data as an example, and the parameter information is listed in Table 1.

[0031] Table 1 Three-dimensional point coordinate parameters of the curved steel structure roof used in the embodiment

[0032]

[0033] S3: Fitting the curved surface of the curved steel structure roof and BIM modeling: Based on the above 10 valid point data, the third-order parametric equation is used to reconstruct the surface, and the three-dimensional BIM model of the curved steel structure roof is established using Revit software, and the control points are calculated based on the node vectors;

[0034] S31: The point set is R i，j (i=0, 1, 2, 3, 4; j=0, 1), which are distributed on 2 different sections, each section contains 5 data points, and two parameter directions are specified: x and z, where the x direction is the plane direction of the site and the z direction is the elevation direction of the site;

[0035] S32: Perform quadratic polynomial fitting on the above data points to obtain the plane curve equation

[0036] N(x)=2.885x 2 -0.176x+1.116

[0037] N(z)=1.932z 2 -2.262z+2.128

[0038] Then the surface equation system P(x, z) is:

[0039]

[0040] S33: Interpolate the x and z directions respectively, according to

[0041] Solve for control points

[0042]

[0043] S34: The above control vertices That is, the points to be measured on the curved steel structure roof; a three-dimensional BIM model of the curved steel structure roof is established in the software, and the coordinates of the points to be measured are imported;

[0044] S4: Use GNSS technology to measure the points to be measured in the BIM model to the construction site, deploy GNSS measuring instruments at the measuring reference points, monitor satellite data for no less than 45 minutes, import the data into the data processing software to extract the baseline vector after monitoring, build a GNSS baseline vector network based on the extracted baseline vector, and automatically derive the theoretical coordinates of the points to be measured; place the target prism at the point to be measured on the curved steel structure roof, and use the ATR function of the measuring robot to automatically search for the target prism. The straight-line distance S between the reference point M and the point to be measured P is 100m, the horizontal angle α between the accumulator point M and the point to be measured P is 37°, the vertical angle β between the reference point M and the point to be measured P is 20°, and the azimuth angle θ of the line connecting the reference point M and the point to be measured P is 53°. The ranging accuracy of the measuring robot is 0.8mm. The remaining parameters and error terms are listed in Table 2:

[0045] Table 2 Parameters of the test points

[0046]

[0047] S5: From the above error terms, it can be seen that the three-dimensional errors of the control points are within 0.02-0.12mm, which meets the engineering specifications.

[0048] Although the specific calculation method of the present invention is described above in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the present invention. Technical personnel in the relevant field should understand that various modifications or variations that can be made by technical personnel in the field without creative work on the basis of the design of the present invention are still within the scope of protection of the present invention.

Claims

1. A GNSS-based intelligent spatial positioning method for curved steel structure roof, characterized in that: include: S1, collecting 3D laser scanning point cloud field data: using the method of arranging base station scanners, using 3D laser scanning technology to collect 3D points of the processed curved steel structure roof in all directions, and obtaining the original point cloud model data of the curved steel structure roof; S2, processing point cloud model data: removing invalid point clouds through point cloud stitching, point cloud overall registration, point cloud cutting, and point cloud denoising; S3, fitting the curved surface of the curved steel structure roof and BIM modeling: according to the processed point cloud data, the third-order parametric equation is used to reconstruct the surface, the three-dimensional BIM model of the curved steel structure roof is established using Revit software, and the control points are calculated according to the node vector; S31, the processed point cloud data set is recorded as R i，j (i=0,1,2,...,r;j=0,1,2,...,s), which are distributed on s+1 different sections, each section contains r+1 data points, and two parameter directions are specified: x and z, where the x direction is the plane direction of the site and the z direction is the elevation direction of the site; S32, construct the surface equation group P(x, z), see formula (1): Where, d i，j is the feature point of the point cloud dataset, N i，l (x), N j，k (z) are plane curves in the x and z directions respectively; S33, interpolate the surface equation group P(x, z) in the x direction to generate r cross-sectional interpolation curves with z as a parameter, and find the control vertices of the cross-sectional curves See formula 2: Where, d i，r is the interpolation point in the x direction, N(z r ) is the cross-section interpolation curve equation; S34, Control Vertices of Section Curves That is, the points to be measured on the curved steel structure roof; a three-dimensional BIM model of the curved steel structure roof is established in the software, and the coordinates of the points to be measured are imported; S4, GNSS control point layout and measurement error calculation: Use GNSS technology to measure the points to be measured in the BIM model to the construction site, deploy GNSS measuring instruments at the measurement reference points, monitor satellite data for no less than 45 minutes, and import the data into the data processing software to extract the baseline vector after monitoring. According to the extracted baseline vector, a GNSS baseline vector network is constructed to automatically derive the theoretical coordinates of the points to be measured; place the target prism at the point to be measured on the curved steel structure roof, use the ATR function of the measurement robot to automatically search for the target prism, and calculate the actual coordinates of the points to be measured according to formula (3): Among them, S is the straight-line distance between the reference point and the point to be measured, X P , Y P , Z P They are the coordinate components of the point to be measured in the x, y, and z directions respectively. M , Y M , Z M are the coordinate components of the reference point in the x, y, and z directions respectively, α is the horizontal angle between the reference point and the point to be measured, β is the vertical angle between the reference point and the point to be measured, and θ is the azimuth of the line connecting the reference point and the point to be measured; Use formula (4) to calculate the error term of the coordinates of the measured point Among them, m Δα 、m Δβ are the error values ​​of the points to be measured, ρ is the theoretical coordinate value of the points to be measured, m s To measure the robot's distance measurement accuracy; S5, check the error value: check whether the error value of the measured point is within the allowable range.

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