Steel truss girder simulation splicing method combining point cloud data and total station data

Abstract

The invention discloses a steel truss girder simulation assembly method combining point cloud data and total station data, and relates to the technical field of data simulation, and the method comprises the following steps: obtaining screw hole information of a plurality of assembly areas of a first steel truss girder assembly section and a second steel truss girder assembly section through a scanner; acquiring reference splicing coordinates of the first steel truss girder splicing section and the second steel truss girder splicing section through a total station; the screw hole information of the multiple splicing areas of the first steel truss girder splicing section and the second steel truss girder splicing section corresponds to the reference splicing coordinates of the first steel truss girder splicing section and the second steel truss girder splicing section; the splicing information of the first area of the splicing plate is registered with the splicing screw hole information of the first steel truss girder splicing section; and the splicing information of the second area of the splicing plate is registered with the splicing screw hole information of the second steel truss girder splicing section. Therefore, the digital splicing posture of the steel truss girder can be checked in advance, and construction adjustment measures can be guided.

Description

Technical Field

[0001] This application relates to the technical field of data simulation, and particularly to a method for simulating the assembly of a steel truss girder by combining point cloud data and total station data. Background Art

[0002] With the continuous development of modern bridge engineering, the steel truss girder structure is widely used in bridge construction due to its high strength, large span, and good mechanical properties. However, the assembly accuracy of the steel truss girder directly affects the overall quality and construction efficiency of the bridge. Traditional physical pre-assembly methods for steel truss girders have many limitations, such as requiring a large amount of temporary sites, long construction periods, high costs, and being unfriendly to the environment. Summary of the Invention

[0003] This application provides a method for simulating the assembly of a steel truss girder by combining point cloud data and total station data to provide a more efficient, low-carbon, and economical solution.

[0004] In a first aspect, this application provides a method for simulating the assembly of a steel truss girder by combining point cloud data and total station data, including the following steps:

[0005] Obtain the screw hole information of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section;

[0006] Obtain the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section;

[0007] Correspond the screw hole information of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section to the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section respectively;

[0008] Register the splicing information of the first area of the splicing plate with the assembled screw hole information of the first steel truss girder assembly section;

[0009] Register the splicing information of the second area of the splicing plate with the assembled screw hole information of the second steel truss girder assembly section.

[0010] During the splicing process of the steel truss girder, since one assembled sub-truss girder has two upper chord bars, and the two lower chord bars need to be spliced with the two upper chord bars and the two lower chord bars of the mother truss girder respectively, there are four separate splicing areas for both the assembled sub-truss girder and the mother truss girder. These four separate splicing areas are not in the same plane, so it is impossible to predict the splicing state of each splicing area during assembly in a unified coordinate system. Therefore, in this application, the screw hole information of multiple splicing areas of the first steel truss girder assembly section and the second steel truss girder assembly section is obtained, and at the same time, the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section are obtained. Then, the screw hole information of multiple splicing areas of the first steel truss girder assembly section and the second steel truss girder assembly section is respectively corresponding to the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section. The splicing information of the first area of the splicing plate is registered with the assembled screw hole information of the first steel truss girder assembly section, and the splicing information of the second area of the splicing plate is registered with the assembled screw hole information of the second steel truss girder assembly section. The four separate splicing areas can be transformed into the same coordinate system through the reference splicing coordinates, and then the registration situation can be fitted. Among them, through the reference splicing coordinates, the sub-truss girder and the mother truss girder can be unified into the same coordinate system respectively. Then, one part of the splicing plate is used to connect the sub-truss girder, and the other part is used to connect the mother truss girder, and the sub-truss girder and the mother truss girder are unified into the same coordinate system again, so that the splicing situation of the steel truss girder can be fitted in the same coordinate system. The fitting method can be used to more accurately and quickly judge the state during the splicing of the steel truss girder and guide the deformation situation of the steel truss girder.

[0011] In some embodiments, the obtaining of the screw hole information of multiple splicing areas of the first steel truss girder assembly section and the second steel truss girder assembly section includes:

[0012] Using a handheld scanner to scan the point clouds of multiple splicing areas of the first steel truss girder assembly section and the second steel truss girder assembly section respectively;

[0013] Preprocessing the point cloud data of multiple splicing areas of the first steel truss girder assembly section and the second steel truss girder assembly section respectively to obtain the assembled screw hole coordinates of multiple areas of the first steel truss girder assembly section and the assembled screw hole coordinates of multiple areas of the second steel truss girder assembly section.

[0014] Handheld scanners usually have high test accuracy. However, when the objects to be tested are not in the same plane, i.e., the same coordinate system, different test areas cannot be integrated, and only point cloud information of discrete areas can be obtained. During the splicing process of steel truss girders, the information of assembly screw holes is the most important information. The assembly process is the process of aligning the screw holes. By using a handheld scanner to scan the point clouds of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section respectively, and preprocessing the point cloud data of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section respectively, the assembly screw hole coordinates of multiple areas of the first steel truss girder assembly section and the assembly screw hole coordinates of multiple areas of the second steel truss girder assembly section can be obtained, and the screw hole coordinate information of each assembly area can be accurately known. It should be noted that the obtained assembly screw hole coordinates are the screw hole coordinate information in the independent coordinate system of each area at this time, and they have not been integrated in the unified coordinate system yet, and it is still impossible to know whether they are suitable for assembly.

[0015] In some embodiments, the accuracy of the handheld scanner is sub-millimeter level. The sub-millimeter level accuracy can make the deviation between the measured screw hole information and the actual situation smaller, thereby improving the accuracy of the fitting result.

[0016] In some embodiments, the preprocessing of the point cloud data includes at least one of point cloud cropping and outlier removal. The extraction method of the screw hole coordinate information can be point selection based on commercial software or processing based on intelligent algorithms to obtain the center coordinates and radius information of the screw hole docking surface. Point cloud cropping refers to removing the areas irrelevant to the assembly through digital means. Outlier removal refers to removing the noise points that appear during the scanning process by using point cloud filtering. Point cloud cropping and outlier removal can make the point cloud data used for fitting the screw hole coordinates more accurate. Specifically, a handheld three-dimensional laser scanner (accuracy of 0.025mm) from Ztek can be used to scan the eight ends of four chord members, with a focus on scanning the screw holes and the inner walls. The point cloud scanning results are used to obtain the coordinate information and diameter by using the circular hole fitting function in the commercial software Polyworks.

[0017] In some embodiments, the obtaining of the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section includes:

[0018] Using a total station to measure the characteristic screw hole coordinates of each assembly area of the first steel truss girder assembly section and the characteristic screw hole coordinates of each assembly area of the second steel truss girder assembly section respectively;

[0019] Establishing the reference splicing coordinates of the first steel truss girder assembly section according to the characteristic screw hole coordinates of each assembly area of the first steel truss girder assembly section;

[0020] Establishing the reference splicing coordinates of the second steel truss girder assembly section according to the characteristic screw hole coordinates of each assembly area of the second steel truss girder assembly section.

[0021] The data measured by the total station is in an overall coordinate system. Each time, only the single-point coordinates of one point can be measured. By measuring the key screw hole coordinates of each assembly area, it can be used for registration, unifying the four areas, that is, the four surfaces, to the same coordinate, that is, the same plane, for registration and fitting. In this way, the four discrete assembly areas can be brought together under the measurement of the total station to the same coordinate system and become a complete assembled area for splicing and fitting. At this time, the first steel truss beam assembly section has a reference splicing coordinate, and the second steel truss beam assembly section has a reference splicing coordinate. The first steel truss beam assembly and the second steel truss beam assembly section still have independent reference splicing coordinates at this time.

[0022] In some embodiments, the method of using the transfer station is adopted to establish the reference splicing coordinates for the characteristic screw hole coordinates of each assembly area. The method of the transfer station is to set up stations on the upstream and downstream of the steel truss beam for observation respectively, set 3 - 4 target points in the middle, and conduct synchronous observations at the two survey stations. Combining with the seven-parameter registration method, the coordinates of the upstream and downstream are unified to achieve the purpose of unifying the entire reference splicing coordinates of the steel truss beam section.

[0023] In some embodiments, the correspondence of the screw hole information of multiple assembly areas of the first steel truss beam assembly section and the second steel truss beam assembly section to the reference splicing coordinates of the first steel truss beam assembly section and the second steel truss beam assembly section includes:

[0024] The four-point consistency algorithm is used to register the screw hole information of multiple assembly areas of the first steel truss beam assembly section and the second steel truss beam assembly section to the reference splicing coordinates of the first steel truss beam assembly section and the second steel truss beam assembly section respectively.

[0025] By corresponding the screw hole information to the reference splicing coordinates respectively, each accurately measured screw hole information can be corresponding to the unified reference splicing coordinates obtained by fitting the corresponding steel truss beam assembly section, so that the discrete screw hole information of the four areas is visually presented within the unified reference splicing coordinates, which is convenient for registration. The four-point consistency algorithm refers to registering two point clouds through the consistency of four screw hole feature points.

[0026] In some embodiments, in the registration of the splicing information of the first area of the splicing plate and the splicing screw hole information of the first steel truss beam assembly section:

[0027] The splicing information of the first area and the second area of the splicing plate is the theoretical design value; and / or,

[0028] The rigid registration algorithm is used to register the splicing information of the first area of the splicing plate and the splicing screw hole information of the first steel truss beam assembly section.

[0029] The splicing plate is a component that spliced the first steel truss girder assembly section and the second steel truss girder assembly section together. Usually, it is laid along the length extension direction of the steel truss girder on the four sides of each steel truss girder assembly section. One part corresponds to the screw holes on the first steel truss girder assembly section, and the other part corresponds to the screw holes on the second steel truss girder assembly section. Through the fastening of the splicing plate, the first steel truss girder assembly section and the second steel truss girder assembly section are assembled. Since the splicing plate is a complete plane and its deformation can be ignored, generally, there is no need to measure the screw hole information or splicing information of the splicing plate, and the theoretical design value can be directly adopted. Rigid registration refers to the registration of the steel truss girder in its pure geometric form without considering the stress deformation state. When using rigid registration to register the splicing information of the first area of the splicing plate with the assembled screw hole information of the first steel truss girder assembly section, the geometric shape remains unchanged.

[0030] In some embodiments, in the registration of the splicing information of the second area of the splicing plate with the assembled screw hole information of the second steel truss girder assembly section:

[0031] The Procrustes analysis method is used to register the splicing information of the second area of the splicing plate with the assembled screw hole information of the second steel truss girder assembly section.

[0032] The Procrustes analysis method refers to finding an optimal translation, rotation, and scaling transformation to minimize the distance between two sets of point clouds. Using the Procrustes analysis method to register all the splicing information of the second area of the splicing plate with the assembled screw hole information of the second steel truss girder assembly section can unify the screw hole coordinates of the splicing plate and the steel truss girder section. Since the splicing plate is a flat plate and is itself in a unified coordinate system, its first area is registered with the first steel truss girder assembly section, and its second area is registered with the second steel truss girder assembly section. And since the assembled areas of the first steel truss girder assembly section and the second steel truss girder assembly section have respectively fitted a unified coordinate system, therefore, through the bridging effect of the splicing plate, the coordinate systems of the first steel truss girder assembly section and the second steel truss girder assembly section, which are two independent coordinate systems, are connected into a unified large coordinate system, and the registration situation of the steel truss girder can be fitted under this unified large coordinate system.

[0033] In some embodiments, after registering the splicing information of the second area of the splicing plate with the assembled screw hole information of the second steel truss girder assembly section, it further includes:

[0034] Determine the abnormal assembled screw holes according to the registration situation.

[0035] When registering, if it is found that the registration information of the splicing information on the splicing plate and the assembled screw hole information of the steel truss girder assembly section does not meet the requirements, usually this screw hole is an abnormal assembled screw hole and needs to be reported to the on-site assembly personnel for debugging before assembly to make the assembled screw holes meet the assembly requirements. Usually, the assembly requirements can be that the passing situation of the screw holes in the splicing information of the second area of the splicing plate and the assembled screw holes of the steel truss girder assembly section conforms to the specification requirements. Brief Description of the Drawings

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0037] Figure 1 It is a flowchart of a method for simulating the assembly of a steel truss girder by combining point cloud data and total station data according to an embodiment of the present application.

[0038] Figure 2 It is a flowchart of a method for simulating the assembly of a steel truss girder by combining point cloud data and total station data according to an embodiment of the present application.

[0039] Figure 3 It is a flowchart of a method for simulating the assembly of a steel truss girder by combining point cloud data and total station data according to an embodiment of the present application.

[0040] Figure 4 It is a flowchart of a method for simulating the assembly of a steel truss girder by combining point cloud data and total station data according to an embodiment of the present application.

[0041] Figure 5 It is a flowchart of a method for simulating the assembly of a steel truss girder by combining point cloud data and total station data according to an embodiment of the present application.

[0042] Figure 6 It is a flowchart of a method for simulating the assembly of a steel truss girder by combining point cloud data and total station data according to Embodiment 1 of the present application. Detailed Embodiments

[0043] To make the objectives, technical solutions, and advantages of the present application clearer, the following will clearly and completely describe the technical solutions of the present application in combination with the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts fall within the scope of protection of the present application.

[0044] With the continuous development of modern bridge engineering, due to its high strength, large span, and good mechanical properties, the steel truss girder structure is widely used in bridge construction. However, the assembly accuracy of the steel truss girder directly affects the overall quality and construction efficiency of the bridge. Traditional physical pre-assembly methods for steel truss girders have many limitations, such as requiring a large amount of temporary sites, long construction periods, high costs, and being unfriendly to the environment.

[0045] In recent years, the application of digital technologies in bridge construction has gradually increased. By using 3D laser scanning technology to obtain the 3D point cloud data of steel truss girders, high-precision digital modeling and pre-assembly can be achieved. This technology can not only significantly improve construction efficiency but also effectively reduce construction errors and costs. However, the measurement method of a single scanner will cause error accumulation. A common method is to integrate the data of each scanner using a large-scale base station scanner or a laser tracker for single-point high-precision measurement. Although the large-range scanner based on the base station scanner can obtain overall coordinates, the measurement accuracy is greatly lost for large-size and long-distance measurements. The method based on single-point measurement of the laser tracker is expensive, which limits its popularization and application.

[0046] In view of this, the present application provides a method for simulating the assembly of a steel truss girder by combining point cloud data and total station data to provide a more efficient, low-carbon and economical solution.

[0047] In the first aspect, as Figure 1 shown, the present application provides a method for simulating the assembly of a steel truss girder by combining point cloud data and total station data, including the following steps:

[0048] S100. Obtain the bolt hole information of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section;

[0049] S200. Obtain the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section;

[0050] S300. Corresponding the bolt hole information of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section to the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section respectively;

[0051] S400. Register the splicing information of the first area of the splicing plate with the bolt hole information of the first steel truss girder assembly section;

[0052] S500. Register the splicing information of the second area of the splicing plate with the bolt hole information of the second steel truss girder assembly section.

[0053] During the splicing process of the steel truss girder, since one assembled sub-truss girder has two upper chord bars, and the two lower chord bars need to be spliced with the two upper chord bars and the two lower chord bars of the mother truss girder respectively, there are four separate splicing areas in both the assembled sub-truss girder and the mother truss girder. These four separate splicing areas are not in the same plane, so it is impossible to predict the splicing state of each splicing area during assembly in a unified coordinate system. Therefore, in this application, the screw hole information of multiple splicing areas of the first steel truss girder assembly section and the second steel truss girder assembly section is obtained, and at the same time, the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section are obtained. Then, the screw hole information of multiple splicing areas of the first steel truss girder assembly section and the second steel truss girder assembly section is respectively corresponding to the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section. The splicing information of the first area of the splicing plate is registered with the assembled screw hole information of the first steel truss girder assembly section, and the splicing information of the second area of the splicing plate is registered with the assembled screw hole information of the second steel truss girder assembly section. The four separate splicing areas can be transformed into the same coordinate system through the reference splicing coordinates, and then the registration situation can be fitted. Among them, through the reference splicing coordinates, the sub-truss girder and the mother truss girder can be unified into the same coordinate system respectively. Then, one part of the splicing plate is used to connect the sub-truss girder, and the other part is used to connect the mother truss girder, and the sub-truss girder and the mother truss girder are unified into the same coordinate system again, so that the splicing situation of the steel truss girder can be fitted in the same coordinate system. The fitting method can be used to more accurately and quickly judge the state of the steel truss girder during splicing and guide the deformation of the steel truss girder.

[0054] Combined with the first aspect, in some embodiments provided by the present application, as Figure 2 shown, the obtaining of the screw hole information of multiple splicing areas of the first steel truss girder assembly section and the second steel truss girder assembly section includes:

[0055] S101. Use a handheld scanner to scan the point clouds of multiple splicing areas of the first steel truss girder assembly section and the second steel truss girder assembly section respectively;

[0056] S102. Preprocess the point cloud data of multiple splicing areas of the first steel truss girder assembly section and the second steel truss girder assembly section respectively to obtain the assembled screw hole coordinates of multiple areas of the first steel truss girder assembly section and the assembled screw hole coordinates of multiple areas of the second steel truss girder assembly section.

[0057] Handheld scanners usually have high test accuracy. However, when the objects to be tested are not in the same plane, that is, in the same coordinate system, different test areas cannot be integrated, and only point cloud information of discrete areas can be obtained. During the splicing process of steel truss girders, the information of assembly screw holes is the most important information. The assembly process is the process of aligning the screw holes. By using a handheld scanner to scan the point clouds of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section respectively, and preprocessing the point cloud data of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section respectively, the assembly screw hole coordinates of multiple areas of the first steel truss girder assembly section and the assembly screw hole coordinates of multiple areas of the second steel truss girder assembly section can be obtained, and the screw hole coordinate information of each assembly area can be accurately known. It should be noted that the obtained assembly screw hole coordinates at this time are the screw hole coordinate information in the independent coordinate system of each area, and have not been integrated in the unified coordinate system, and it is still impossible to know whether they are suitable for assembly.

[0058] Combined with the first aspect, in some embodiments provided by the present application, the accuracy of the handheld scanner is sub-millimeter level. The sub-millimeter level accuracy can make the deviation between the measured screw hole information and the actual situation smaller, thereby improving the accuracy of the fitting result.

[0059] Combined with the first aspect, in some embodiments provided by the present application, the preprocessing of the point cloud data includes at least one of point cloud cropping and outlier removal. The extraction method of the screw hole coordinate information can be point selection based on commercial software or processing based on intelligent algorithms to obtain the center coordinates and radius information of the screw hole docking surface. Point cloud cropping refers to removing the areas irrelevant to the assembly through digital means. Outlier removal refers to removing the noise points that appear during the scanning process by using point cloud filtering. Point cloud cropping and outlier removal can make the point cloud data used for fitting the screw hole coordinates more accurate. Specifically, a handheld three-dimensional laser scanner (accuracy of 0.025 mm) from Ztek can be used to scan the eight ends of four chord members, with a focus on scanning the screw holes and the inner walls. The point cloud scanning results can be used to obtain the coordinate information and diameter by using the circular hole fitting function in the commercial software Polyworks.

[0060] Combined with the first aspect, in some embodiments provided by the present application, as Figure 3 shown, the obtaining of the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section includes:

[0061] S201. Use a total station to measure the characteristic screw hole coordinates of each assembly area of the first steel truss girder assembly section and the characteristic screw hole coordinates of each assembly area of the second steel truss girder assembly section respectively;

[0062] S202. Establish the reference splicing coordinates of the first steel truss girder assembly section according to the characteristic screw hole coordinates of each assembly area of the first steel truss girder assembly section;

[0063] S203. Establish the reference splicing coordinates of the second steel truss girder assembly section according to the characteristic screw hole coordinates of each assembly area of the second steel truss girder assembly section.

[0064] The data measured by the total station is in an overall coordinate system. Each time, only the single-point coordinates of one point can be measured. By measuring the key screw hole coordinates of each assembly area, it can be used for registration. The four areas, that is, the four surfaces, can be unified to the same coordinate, that is, the same plane, for registration fitting. In this way, the discrete four assembly areas can be converged to the same coordinate system under the measurement of the total station and become a fitted complete splicing area, which can be used for splicing fitting. At this time, the first steel truss girder assembly section has a reference splicing coordinate, and the second steel truss girder assembly section has a reference splicing coordinate. The first steel truss girder assembly and the second steel truss girder assembly section still have independent reference splicing coordinates at this time.

[0065] Combined with the first aspect, in some embodiments provided by the present application, the reference splicing coordinates of the characteristic screw hole coordinates of each assembly area are established by means of a transfer station. The method of the transfer station is to set up stations for observation on the upstream and downstream of the steel truss girder respectively, and 3-4 target points are set in the middle. Observation is carried out synchronously at the two survey stations. Combining the seven-parameter registration method, the coordinates of the upstream and downstream are unified to achieve the purpose of unifying the entire reference splicing coordinates of the steel truss girder section.

[0066] Combined with the first aspect, in some embodiments provided by the present application, as Figure 4 shown, the corresponding the screw hole information of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section to the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section respectively includes:

[0067] S301. Use the four-point consistency algorithm to respectively correspond the screw hole information of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section to the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section.

[0068] By corresponding the screw hole information to the reference splicing coordinates respectively, each accurately measured screw hole information can be corresponded to the unified reference splicing coordinates obtained by fitting the corresponding steel truss girder assembly section, so that the discrete screw hole information of the four areas is visually presented within the unified reference splicing coordinates, which is convenient for registration. The four-point consistency algorithm refers to registering two point clouds through the consistency of four screw hole feature points.

[0069] Combined with the first aspect, in some embodiments provided by the present application, in the registration of the splicing information of the first area of the splicing plate and the splicing screw hole information of the first steel truss girder assembly section: the splicing information of the first area and the second area of the splicing plate is the theoretical design value.

[0070] In combination with the first aspect, in some embodiments provided by the present application, in the process of registering the splicing information of the first region of the splicing plate with the assembly screw hole information of the first steel truss girder assembly section: a rigid registration algorithm is used to register the splicing information of the first region of the splicing plate with the assembly screw hole information of the first steel truss girder assembly section.

[0071] The splicing plate is a component that joins the first steel truss girder assembly section and the second steel truss girder assembly section. Usually, it is laid along the length extension direction of the steel truss girder on the four side surfaces of each steel truss girder assembly section. One part corresponds to the screw holes on the first steel truss girder assembly section, and the other part corresponds to the screw holes on the second steel truss girder assembly section. By fastening the splicing plate, the first steel truss girder assembly section and the second steel truss girder assembly section are assembled. Since the splicing plate is a complete plane and its deformation can be ignored, generally, there is no need to measure the screw hole information or splicing information of the splicing plate, and the theoretical design values can be directly used. Rigid registration refers to the registration of the steel truss girder in the pure geometric form without considering the stress deformation state. Using rigid registration to register the splicing information of the first region of the splicing plate with the assembly screw hole information of the first steel truss girder assembly section can keep the geometric shape unchanged.

[0072] In combination with the first aspect, in some embodiments provided by the present application, in the process of registering the splicing information of the second region of the splicing plate with the assembly screw hole information of the second steel truss girder assembly section: a Procrustes analysis method is used to register the splicing information of the second region of the splicing plate with the assembly screw hole information of the second steel truss girder assembly section.

[0073] The Procrustes analysis method means finding an optimal translation, rotation, and scaling transformation to minimize the distance between two sets of point clouds. Using the Procrustes analysis method to register the splicing information of the second region of the splicing plate with the assembly screw hole information of the second steel truss girder assembly section can unify the screw hole coordinates of the splicing plate and the steel truss girder section. Since the splicing plate is a flat plate and is itself in a unified coordinate system, its first region is registered with the first steel truss girder assembly section, and its second region is registered with the second steel truss girder assembly section. And since the assembly regions of the first steel truss girder assembly section and the second steel truss girder assembly section have respectively fitted out a unified coordinate system, therefore, through the bridging effect of the splicing plate, the coordinate systems of the first steel truss girder assembly section and the second steel truss girder assembly section, which are two independent coordinate systems, are connected into a unified large coordinate system, and the registration situation of the steel truss girder can be fitted under this unified large coordinate system.

[0074] In combination with the first aspect, in some embodiments provided by the present application, as Figure 5 shown, after registering the splicing information of the second region of the splicing plate with the assembly screw hole information of the second steel truss girder assembly section, it further includes:

[0075] S600. Determine the abnormal assembly screw holes according to the registration situation.

[0076] When registering, if it is found that the splicing information on the splicing plate does not meet the requirements for the registration information of the splicing screw holes of the steel truss girder assembly section, usually this screw hole is an abnormal assembly screw hole and needs to be reported to the on-site assembly personnel for debugging before assembly to make the assembly screw holes meet the assembly requirements. Usually, the assembly requirements can be that the overlapping area between the screw holes in the splicing information of the second area of the splicing plate and the assembly screw holes of the steel truss girder assembly section is greater than or equal to a threshold value, such as 99%.

[0077] The technical solutions provided by the present application will be described in detail below with reference to the embodiments.

[0078] Embodiment 1

[0079] A method for simulating the assembly of a steel truss girder by combining point cloud data and total station data, as Figure 6 shown, includes the following steps:

[0080] Use a handheld scanner to scan the end point clouds of the sub-section (the second steel truss girder assembly section) and the mother section (the first steel truss girder assembly section) of the steel truss girder respectively, preprocess the point cloud data of the sub-section and the mother section, and obtain the screw hole coordinate information. Based on the handheld three-dimensional laser scanner of Detek (with an accuracy of 0.025 mm), scan the eight ends of the four chord members, focus on scanning the screw holes and the inner walls, and use the circular hole fitting function in the commercial software Polyworks to obtain the coordinate information and diameter of the point cloud scan results;

[0081] Use a total station to obtain the global positioning screw hole coordinates of the sub-section and the mother section respectively. Set up stations at the upstream and downstream of the steel truss girder section respectively with a total station, set four visible points in the middle as transfer stations, and observe these four points simultaneously with two measuring stations. Use the seven-parameter method to register the upstream and downstream points;

[0082] Use the method of taking pictures to obtain the corresponding homologous points of the scanner and the total station, register the coordinates of the total station and the scanner based on the four-point consistency algorithm, and obtain the coordinates of the point clouds after registration of the chord member mother section and the sub-section according to the rotation and translation matrix used for registration;

[0083] Obtain the design values of the splicing plate, and then register the design coordinates of the splicing plate onto the mother section, and register the local coordinate system of the splicing plate onto the total station coordinate system of the mother section;

[0084] Register the screw holes at the other four ends of the mother section onto the mother section respectively, and obtain the screw hole information of the splicing plate after registration at the four ends;

[0085] Register the spliced sub-section of the splicing plate and the four steel truss girder ends of the sub-section. The registration method uses the Procrustes analysis method to ensure that the four ends reach the optimal registration position and attitude simultaneously;

[0086] Visualize the results after registering the four ends to show the deformation of the truss segments in various directions after digital assembly.

[0087] By jointly using a total station and a 3D laser scanner, the accuracy and efficiency of the pre-assembly of steel truss beams can be further improved, while reducing costs and facilitating on-site application, providing a more efficient, low-carbon and economical solution for bridge construction.

[0088] In the description of the embodiments of this application, the terms "including" and "having" and any variations thereof in the specification, claims and the above-mentioned drawings are intended to cover non-exclusive inclusion. For example, a process, method, device, product or equipment that includes a series of steps or units is not limited to the listed steps or units, but may optionally further include steps or units not listed, or may optionally further include other steps or units inherent to these processes, methods, products or equipment. Descriptions such as "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequential order, nor do they limit that "first", "second" and "third" are of different types.

[0089] In the description of the embodiments of this application, terms such as "exemplary", "for example" or "for instance" are used to present examples, illustrations or explanations. Any embodiment or design solution described as "exemplary", "for example" or "for instance" in the embodiments of this application should not be construed as being more preferred or having more advantages than other embodiments or design solutions. Rather, the use of words such as "exemplary", "for example" or "for instance" is intended to present related concepts in a specific manner.

[0090] In the description of the embodiments of this application, unless otherwise specified, " / " means "or". For example, A / B may mean A or B; "and / or" in the text is merely a description of the relationship between associated objects, indicating that there can be three relationships. For example, A and / or B may mean: A exists alone, A and B exist simultaneously, and B exists alone. Additionally, in the description of the embodiments of this application, "a plurality of" means two or more than two.

[0091] In some processes described in the embodiments of this application, there are multiple operations or steps that appear in a specific order. However, it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of this application or may be executed in parallel. The serial numbers of the operations are only used to distinguish different operations, and the serial numbers themselves do not represent any order of execution. Additionally, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0092] The above are only the preferred embodiments of the present application, and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall be similarly included in the patent protection scope of the present application.

Claims

1. A method for simulating the assembly of a steel truss beam by combining point cloud data and total station data, characterized in that It includes the following steps: Obtain the screw hole information of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section; Obtain the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section; Correspond the screw hole information of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section to the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section respectively; Register the splicing information of the first area of the splicing plate with the assembled screw hole information of the first steel truss girder assembly section; Register the splicing information of the second area of the splicing plate with the assembled screw hole information of the second steel truss girder assembly section.

2. The method for simulating the assembly of a steel truss girder by combining point cloud data and total station data as described in claim 1, wherein The obtaining the screw hole information of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section includes: Use a handheld scanner to scan the point clouds of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section respectively; Preprocess the point cloud data of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section respectively to obtain the assembled screw hole coordinates of multiple areas of the first steel truss girder assembly section and the assembled screw hole coordinates of multiple areas of the second steel truss girder assembly section.

3. The method for simulating the assembly of a steel truss girder by combining point cloud data and total station data according to claim 2, wherein, The accuracy of the handheld scanner is sub-millimeter level.

4. The method for simulating the assembly of a steel truss girder by combining point cloud data and total station data according to claim 2, wherein The preprocessing of the point cloud data includes at least one of point cloud cropping and outlier removal.

5. The method for simulating the assembly of a steel truss girder by combining point cloud data and total station data according to claim 1, characterized in that, The obtaining the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section includes: Use a total station to measure the characteristic screw hole coordinates of each assembly area of the first steel truss girder assembly section and the characteristic screw hole coordinates of each assembly area of the second steel truss girder assembly section respectively; Establish the reference splicing coordinates of the first steel truss girder assembly section according to the characteristic screw hole coordinates of each assembly area of the first steel truss girder assembly section; Establish the reference splicing coordinates of the second steel truss girder assembly section according to the characteristic screw hole coordinates of each assembly area of the second steel truss girder assembly section.

6. The method for simulating the assembly of a steel truss girder by combining point cloud data and total station data according to claim 5, wherein Use the method of transfer station points to establish the reference splicing coordinates based on the characteristic screw hole coordinates of each assembly area.

7. The method for simulating the assembly of a steel truss girder by combining point cloud data and total station data according to claim 1, wherein The corresponding the screw hole information of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section to the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section respectively includes: Use the four-point consistency algorithm to correspond the screw hole information of multiple assembly areas of the first steel truss girder assembly section and the second steel truss girder assembly section to the reference splicing coordinates of the first steel truss girder assembly section and the second steel truss girder assembly section respectively.

8. The method for simulating the assembly of a steel truss girder by combining point cloud data and total station data according to claim 1, wherein In the registering the splicing information of the first area of the splicing plate with the assembled screw hole information of the first steel truss girder assembly section: The splicing information of the first area and the second area of the splicing plate is the theoretical design value; and / or, Use a rigid registration algorithm to register the splicing information of the first area of the splicing plate with the assembled screw hole information of the first steel truss girder assembly section.

9. The method for simulating the assembly of a steel truss girder by combining point cloud data and total station data according to claim 1, characterized in that, In the registering the splicing information of the second area of the splicing plate with the assembled screw hole information of the second steel truss girder assembly section: Use the Procrustes analysis method to register the splicing information of the second area of the splicing plate with the assembled screw hole information of the second steel truss girder assembly section.

10. The method for simulating the assembly of a steel truss girder by combining point cloud data and total station data as described in claim 1, wherein, After the registering the splicing information of the second area of the splicing plate with the assembled screw hole information of the second steel truss girder assembly section, it further includes: Determine the abnormal assembled screw holes according to the registration situation.

Images