Plate size detection device for road and bridge construction based on laser measurement

Abstract

The invention discloses a laser measurement-based plate size detection device for road and bridge construction, relates to the technical field of road and bridge construction, and aims to solve the problems of strong manual dependence, insufficient intuition and poor collaboration with a construction system in traditional plate detection. The device comprises a mounting frame, a conveying mechanism, a positioning mechanism, a detection mechanism, a console, a laser detection assembly and an equipment control and data processing system, wherein the equipment control and data processing system is integrated with a 3D modeling adaptation module, a plate three-dimensional model can be constructed and optimized based on size parameters of laser measurement, visual interaction of the model is achieved through a console, and butt joint with external construction management software is supported. According to the device, through fusion of laser non-contact measurement, automatic positioning and synchronous conveying, 3D modeling and construction cooperation technologies, high-precision and high-efficiency detection of the plate size is achieved, meanwhile, the visual three-dimensional size display and construction system cooperation capability is provided, and full-process technical support is provided for road and bridge construction plate quality control.

Description

Technical Field

[0001] This invention relates to the field of road and bridge construction technology, and in particular to a laser-based device for detecting the dimensions of road and bridge construction materials. Background Technology

[0002] In road and bridge construction, slabs are crucial building materials, and their dimensional accuracy directly impacts the quality and progress of the project. Traditional methods for inspecting slab dimensions mostly rely on manual measurement, which is inefficient and lacks guaranteed accuracy, failing to meet the demands of modern large-scale road and bridge construction. With the development of laser measurement technology, laser-based non-contact inspection methods are gradually being applied to the field of slab dimension inspection, improving inspection efficiency and accuracy to a certain extent.

[0003] However, existing laser-based sheet metal dimension inspection devices still have many shortcomings. On the one hand, most of these devices can only output simple dimensional values, making it difficult for construction personnel to intuitively understand the overall shape and size distribution of the sheet metal, which is not conducive to pre-construction simulation and quality assessment. On the other hand, there is a lack of effective data interaction and collaboration between the inspection devices and the construction management system, which fails to provide strong support for material management, assembly simulation, and other aspects of the construction process.

[0004] Furthermore, in road and bridge construction, precise positioning and conveying of slabs are required to ensure the accuracy and consistency of inspection. However, existing positioning and conveying mechanisms lack stability and flexibility, and cannot adequately adapt to the inspection needs of slabs of different specifications. Therefore, it is necessary to provide a laser-based slab dimensional inspection device for road and bridge construction to solve the aforementioned technical problems. Summary of the Invention

[0005] To address the aforementioned issues, this invention aims to propose a laser-based device for detecting the dimensions of slabs used in road and bridge construction. This device can accurately detect the dimensions of slabs and visually display their shape and size information using 3D modeling technology. Furthermore, it can interface with road and bridge construction BIM software to provide strong support for construction simulation and quality analysis.

[0006] To achieve the above objectives, the technical solution of the present invention is implemented as follows: A laser-based device for detecting the dimensions of bridge and road construction materials includes a mounting frame, a first conveyor belt, a second conveyor belt, a positioning mechanism, a detection mechanism, a control panel, a laser displacement sensor, a laser emitter, and an equipment control and data processing system. A power motor is mounted on one side of the mounting frame. The positioning mechanism includes a positioning platform and a drive motor mounted on one end of the positioning platform. The control panel is mounted on one side of the mounting frame. The equipment control and data processing system operates within the control panel and is communicatively connected to the power motor, the drive motor, the distance detection component, and the position detection component in the positioning mechanism. It is used to control the equipment operation and collect and process detection data.

[0007] Furthermore, the conveying mechanism includes a first conveyor belt and a second conveyor belt installed at the front and rear ends of the mounting frame; both ends of the first and second conveyor belts are equipped with drive rollers and multiple support rollers located between the two drive rollers; drive wheels are installed on one side of the shaft of each drive roller at both ends, and belts are sleeved on the outer sides of the two drive wheels. The positioning mechanism is installed on the first conveyor belt and is used to position and center the plate. It includes a Z-shaped moving frame that is slidably installed on the positioning platform and a bidirectional lead screw connected to the output end of the drive motor through a coupling. The Z-shaped moving frame and the bidirectional lead screw are connected in a transmission connection. A guide rod is installed on the inner side of the moving frame. Multiple rollers are equidistantly rotatably installed on the guide rod. The laser emitter is installed on one side of the front end of the guide rod. The detection mechanism includes two mounting rods, one upper and one lower, installed on the inner side of the mounting frame. The laser displacement sensors are respectively installed on the mounting rods. The two sets of laser displacement sensors face each other and are located at the upper and lower ends of the gap between the first conveyor belt and the second conveyor belt, respectively. The output end of the power motor is equipped with an active transmission component, and driven transmission components are engaged on both sides of the active transmission component. The two driven transmission components are respectively connected to the transmission roller shafts at one end of the first conveyor belt and the second conveyor belt, and are used to drive the first conveyor belt and the second conveyor belt to operate synchronously.

[0008] Furthermore, the equipment control and data processing system includes a conveyor belt synchronization control unit, a positioning drive unit, and a data acquisition and processing unit; The conveyor belt synchronization control unit is used to send control signals to the power motor and control the first and second conveyor belts to operate synchronously through the transmission parameters of the active and driven transmission components. The positioning drive unit is used to receive the position signal from the laser emitter and send a drive signal to the drive motor to control the rotation of the bidirectional lead screw, thereby achieving the centering positioning of the moving frame on the plate. The data acquisition and processing unit is used to acquire the thickness and length data of the plate and the width data of the laser emitter through the laser displacement sensor, and calculate the plate parameters after filtering and calibration. The plate parameters include the plate width, thickness and length. The plate parameters are compared with the preset plate standard parameters to determine whether the plate is qualified.

[0009] Furthermore, the device control and data processing system integrates a 3D modeling adaptation module, which includes: The 3D model generation unit is used to construct an initial three-dimensional model of the board based on the calibrated board parameters, using a parametric modeling algorithm. The model optimization unit is used to smooth the surface of the initial 3D model using the moving least squares method and adaptively complete the missing edge data. The model interaction and display unit is used to realize the visualization display and interactive operation of the three-dimensional model of the board material on the touch screen configured on the control panel.

[0010] Furthermore, based on the parametric modeling algorithm, an initial three-dimensional model of the board is constructed using the calibrated board parameters, specifically as follows: Coordinate system definition: A three-dimensional coordinate system is established with the starting point O of the plate entering the inspection area as the origin, the length direction as the X-axis, the width direction as the Y-axis, and the thickness direction as the Z-axis; In a three-dimensional coordinate system, the length L and width W of the plate are divided into discrete grid points according to a preset precision. ,in ; Its discrete grid points The formula for calculating the X-coordinate is as follows: The formula for calculating the Y-coordinate is: ,in, , ,in , The preset grid precision; If there are discrete grid points that are not directly measured Then, the thickness values ​​of the measurement points near the point are identified, and the discrete grid point that was not directly measured is solved by the least squares method using the coordinates and thickness values ​​of the nearby measurement points. calibrated plate thickness data Associated with corresponding grid points, forming 3D vertices. ; By connecting adjacent vertices using a triangulation algorithm, a three-dimensional mesh model of the plate surface is generated, referred to as the initial three-dimensional model. The model boundary lines and dimensioning references are also generated.

[0011] Furthermore, the moving least squares method is used to smooth the surface of the initial 3D model, and adaptive completion is performed on missing edge data. Specifically: The moving least squares method is used to smooth the discrete grid points on the surface of the initial 3D model, and the coordinates of any discrete grid point are identified as follows: Select k neighboring points within its neighborhood, denoted as . Construct a weighted least squares objective function: ,in, For the weight function, , , The fitting coefficients are used to obtain the smoothed thickness value after solving. ; Identify missing edge data by marking the coordinates of discrete grid points on the edge of the board that are not covered by the sensor as missing data points. Let its nearest valid point be denoted as Calculate the thickness gradient And complete the thickness, the formula is: .

[0012] Furthermore, the touchscreen on the control panel enables the visualization and interactive operation of the 3D model of the board material, specifically including: The optimized 3D model is rendered in real time using polygon rendering technology, supporting surface texture and dimension annotation; The user's touch commands are analyzed, and the pose of the 3D model of the board material in the screen coordinate system is updated through a transformation matrix. It also supports users clicking on any position of the model to locate the three-dimensional coordinates through the ray detection algorithm, and displays the thickness value of that point and its deviation from the standard value; Identify the thickness of the board at any point in the 3D model of the board, compare the board thickness with its preset normal range, and if the board thickness is not within its preset normal range, mark the point as an out-of-tolerance thickness point; connect adjacent out-of-tolerance thickness points to obtain the thickness out-of-tolerance region, and display and mark the deviation value of the thickness out-of-tolerance region and the average deviation value of the region with a preset highlight color.

[0013] Furthermore, the equipment control and data processing system also includes a construction simulation interface unit, which is used to achieve compatible integration between the 3D model of the slab and external road and bridge construction BIM software.

[0014] Furthermore, the construction simulation interface unit includes: Format conversion: The optimized 3D model data of the board material is encoded and converted according to the STL or OBJ format specifications. STL format: Stores the normal vector and coordinates of the three vertices of a triangle facet; OBJ format: Stores 3D vertex coordinates, texture coordinates, and patch indexes, and supports additional thickness attribute information; Precision configuration: Provides options for simplifying the 3D model of the sheet material; Data encapsulation: The model file is associated with the unique identifier of the board material and standard dimensional parameters to generate a data package containing complete information, which is then transmitted to the BIM software through a standardized interface.

[0015] Beneficial effects: 1. This device achieves synchronous operation of the conveyor belt through a power transmission component, combined with the screw drive of the positioning mechanism and laser position detection, to realize automatic centering and stable conveying of the sheet metal. The equipment control and data processing system automatically completes data acquisition, filtering calibration, and dimensional calculation, replacing manual operation, reducing errors caused by human intervention, and adapting to the continuous inspection needs in large-scale road and bridge construction.

[0016] 2. The calibrated dimensional parameters are converted into a 3D model through a 3D modeling adaptation module. After optimization using the moving least squares method and edge completion, the model can be viewed interactively on a touch screen, and out-of-tolerance areas can be marked. It also supports exporting to BIM software, providing visualized data for pre-construction simulation assembly and quality assessment, strengthening the supporting role of inspection data in construction decisions, and solving the problem that traditional inspection only outputs numerical values ​​and is difficult to intuitively perceive the shape of the board.

[0017] 3. This device employs a bidirectional screw-driven movable positioning component, adaptable to the positioning needs of different sized plates; laser non-contact detection combined with filtering algorithms reduces the impact of environmental interference. The equipment control and data processing system integrates anomaly monitoring and alarm functions, providing real-time feedback on equipment status and dimensional deviation information, ensuring a stable and reliable detection process, improving the equipment's applicability in complex construction environments, and solving the problems of insufficient positioning flexibility and weak environmental adaptability of existing equipment.

[0018] In summary, this device integrates laser measurement, intelligent control, and 3D modeling technologies to improve detection accuracy and efficiency while enabling visualized display of dimensional data and collaboration with construction systems. It solves the problems of manual dependence, insufficient intuitiveness, and poor adaptability of traditional detection methods, providing full-process technical support for the quality control of road and bridge construction materials. Attached Figure Description

[0019] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 A perspective view of Embodiment 1 of the laser-based plate size detection device for road and bridge construction provided by the present invention; Figure 2 This is a schematic diagram of the internal structure of the device proposed in this invention; Figure 3 This is a schematic diagram of the detection mechanism proposed in this invention; Figure 4 This is a schematic diagram of the structure of the power motor proposed in this invention. Figure 5 This is a schematic diagram of the positioning mechanism proposed in this invention; Figure 6 This is a schematic diagram of the equipment control and data processing system of Embodiment 2 of the laser-based plate size detection device for road and bridge construction provided by the present invention.

[0020] The following are the labels in the diagram: 1. Mounting frame; 2. First conveyor belt; 3. Second conveyor belt; 4. Control panel; 5. Power motor; 6. Active transmission component; 7. Driven transmission component; 8. Transmission roller; 9. Support roller; 10. Belt; 11. Drive motor; 12. Positioning table; 13. Bidirectional lead screw; 14. Moving frame; 15. Guide rod; 16. Roller; 17. Laser emitter; 18. Laser displacement sensor. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. The singular forms “group,” “class,” and “the” as used in this disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0023] It should be understood that although the terms first, second, third, etc., may be used in this disclosure to describe various information, such information should not be limited to these terms. These terms are used only to distinguish information of the same type from one another. For example, without departing from the scope of this disclosure, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0024] Example 1 Please refer to the following: Figure 1-5A laser-based plate size detection device for road and bridge construction includes a mounting frame 1, a first conveyor belt 2, a second conveyor belt 3, a positioning mechanism, a detection mechanism, a control panel 4, a laser displacement sensor 18, a laser emitter 17, and an equipment control and data processing system. The conveying mechanism includes a first conveyor belt 2 and a second conveyor belt 3 installed at the front and rear ends of the mounting frame 1; both ends of the first conveyor belt 2 and the second conveyor belt 3 are equipped with drive rollers 8 and multiple support rollers 9 located between the two drive rollers 8; drive wheels are installed on one side of the shaft of the drive rollers 8 at both ends, and belts 10 are sleeved on the outside of the two drive wheels. The positioning mechanism is installed on the first conveyor belt 2 and is used to position and center the plate. It includes a positioning table 12, a Z-shaped moving frame 14 slidably installed on the positioning table 12, a drive motor 11 installed at one end of the positioning table 12, and a bidirectional lead screw 13 connected to the output end of the drive motor 11 through a coupling. The Z-shaped moving frame 14 is connected to the bidirectional lead screw 13 in a transmission connection. A guide rod 15 is installed on the inner side of the moving frame 14, and multiple rollers 16 are equidistantly rotatably installed on the guide rod 15. A laser emitter 17 is installed on one side of the front end of the guide rod 15. The detection mechanism includes two mounting rods installed on the inner side of the mounting frame 1, and laser displacement sensors 18 are respectively installed on the mounting rods; the two sets of laser displacement sensors 18 are oriented opposite each other, and the two sets of laser displacement sensors 18 are respectively located at the upper and lower ends of the gap between the first conveyor belt 2 and the second conveyor belt 3. A power motor 5 is installed on one side of the mounting frame 1. An active transmission component 6 is installed at the output end of the power motor 5. Driven transmission components 7 are engaged on both sides of the active transmission component 6. The two driven transmission components 7 are respectively connected to the shaft of the transmission roller 8 at one end of the first conveyor belt 2 and the second conveyor belt 3, and are used to drive the first conveyor belt 2 and the second conveyor belt 3 to operate synchronously.

[0025] Example 2 Please refer to the following: Figure 6 As shown, based on the laser-based measurement device for detecting the dimensions of road and bridge construction materials provided in Embodiment 1 of this embodiment, Embodiment 2 of this embodiment proposes another laser-based measurement device for detecting the dimensions of road and bridge construction materials. Embodiment 2 is merely a preferred embodiment of Embodiment 1, and the implementation of Embodiment 2 will not affect the individual implementation of Embodiment 1.

[0026] Specifically, the difference between the laser-based measurement-based dimensional detection device for road and bridge construction materials provided in Embodiment 2 of this example and the following is that: The equipment control and data processing system operates in the control panel 4 and is connected to the power motor 5, drive motor 11, distance detection component and position detection component in the positioning mechanism. It is used to control the operation of the equipment and collect and process detection data. The equipment control and data processing system also includes a 3D modeling adaptation module, which includes: The 3D model generation unit is used to construct an initial three-dimensional model of the board based on the calibrated board parameters, using a parametric modeling algorithm. The model optimization unit is used to smooth the surface of the initial 3D model using the moving least squares method and adaptively complete the missing edge data. The smoothed and completed initial 3D model is denoted as the plate 3D model. The model interaction and display unit is used to realize the visualization display and interactive operation of the three-dimensional model of the board material on the touch screen configured on the control panel.

[0027] In this embodiment, the equipment control and data processing system includes a conveyor belt synchronization control unit, a positioning drive unit, and a data acquisition and processing unit; The conveyor belt synchronization control unit is used to send control signals to the power motor 5, and control the synchronous operation of the first conveyor belt 2 and the second conveyor belt 3 through the transmission parameters of the active transmission component 6 and the driven transmission component 7, specifically: The transmission ratio is calculated based on the tooth count parameters of the driving transmission component 6 and the driven transmission component 7. The tooth count parameters include the preset tooth counts of the driving transmission component 6 and the driven transmission component 7, denoted as follows: , Its calculated transmission ratio The formula is ; The output speed of motor 5 is set according to the preset task and recorded as follows: If the diameter D of the drive roller 8 is given, then the rotational speed of the drive roller is given. Conveyor belt linear speed ; It adopts closed-loop control logic, collects motor speed feedback signals in real time, and compensates for speed deviation by dynamically adjusting the output pulse frequency, ensuring that the two conveyor belts transport the board synchronously and avoiding board deviation during the transport process.

[0028] The positioning drive unit receives the position signal from the laser emitter 17 and sends a drive signal to the drive motor 11 to control the rotation of the bidirectional lead screw 13, thereby achieving the centering positioning of the moving frame 14 on the plate. Specifically: Receive the laser reflection signal from laser emitter 17 and analyze the edge position information of the board, including the position of the left edge. Right edge position The preset detection path center position is The offset between the actual center position of the board and the center position of the preset detection path is calculated based on the edge position information of the board. The calculation formula is Offset Calculation formula ; Obtain the pitch of the bidirectional lead screw 13 as P. To eliminate the offset , the two moving frames need to be adjusted in the center direction by a total displacement of 2 , then the rotation angle required for the drive motor 11 ; The data acquisition and processing unit is used to collect the thickness, length data of the sheet material and the width data of the laser emitter 17 through the laser displacement sensor 18, and calculate the sheet material parameters after filtering and calibration. Specifically: Collect the original data of the laser emitter 17 and the laser displacement sensor 18 at a preset frequency through the communication interface. After filtering to eliminate environmental interference, calculate the size of the sheet material in combination with the laser propagation characteristics and the conveyor belt movement parameters, and calibrate and compensate for the sensor installation error: Obtain the time difference between the laser emission and reflection of the laser emitter 17 as , given that the speed of light is c, then the width of the sheet material ; Obtain the initial installation distance between the upper and lower groups of laser displacement sensors 18 as H. The upper sensor detects the distance from the upper surface of the sheet material as , and the lower sensor detects the distance from the lower surface of the sheet material as , then the thickness of the sheet material ; The duration of the detection area by the laser displacement sensor 18 is , then the length of the sheet material ; Record the calculated width, thickness, and length of the sheet material as the initial sheet material parameters; Filter the sheet material parameters sampled continuously for a set number of times; respectively set an error compensation value for any sheet material parameter (the error compensation value is obtained through a standard sheet material calibration experiment and stored in the system parameter library), and use the set error compensation value to calibrate the corresponding sheet material parameter to obtain the calibrated sheet material parameters, including the calibrated width of the sheet material , thickness , length ; Judge whether the sheet material is qualified according to the comparison between the sheet material parameters and the preset sheet material standard parameters: When the detected sheet material parameters meet , it is determined that the sheet material is qualified, otherwise it is determined to be unqualified; among them, , , are the preset standard width, thickness, and length of the sheet material respectively, , , These are the tolerances corresponding to the width, thickness, and length of the sheet material, respectively, and all are configurable parameters.

[0029] It should be noted that the conveyor belt synchronous control unit ensures stable conveying of the sheet material and avoids deviation through precise calculation of transmission parameters and closed-loop speed regulation, laying the foundation for detection accuracy. The positioning drive unit accurately calculates the offset based on laser edge detection and lead screw transmission to achieve centered positioning of the sheet material and ensure consistent detection benchmarks. The data acquisition and processing unit combines laser characteristics and filtering calibration algorithms to complete size calculations and achieves qualification judgment through standard comparison. The three work together to achieve fully automatic and high-precision detection of sheet material dimensions, providing reliable data support for subsequent 3D modeling and improving detection efficiency and quality control level.

[0030] In this embodiment, based on the parametric modeling algorithm, an initial three-dimensional model of the board is constructed based on the calibrated board parameters, specifically as follows: Coordinate system definition: A three-dimensional coordinate system is established with the starting point O of the plate entering the inspection area as the origin, the length direction as the X-axis, the width direction as the Y-axis, and the thickness direction as the Z-axis; In a three-dimensional coordinate system, the length L and width W of the plate are divided into discrete grid points according to a preset precision. ,in ; Its discrete grid points The formula for calculating the X-coordinate is as follows: The formula for calculating the Y-coordinate is: ,in, , ,in , The preset grid precision; If there are discrete grid points that are not directly measured Then, the thickness values ​​of the measurement points near the point are identified, and the discrete grid point that was not directly measured is solved by the least squares method using the coordinates and thickness values ​​of the nearby measurement points.

[0031] calibrated plate thickness data Associated with corresponding grid points, forming 3D vertices. ; By connecting adjacent vertices using a triangulation algorithm, a three-dimensional mesh model of the plate surface is generated, referred to as the initial three-dimensional model. The model boundary lines and dimensioning references are also generated.

[0032] This section establishes a three-dimensional coordinate system and meshes to transform the calibrated board parameters into structured three-dimensional data. Unmeasured mesh points are filled using least squares interpolation to ensure model integrity. An initial three-dimensional model with boundary lines and dimension annotations is constructed by combining triangulation, achieving accurate digital restoration of the board's morphology. This lays the data foundation for subsequent model optimization and visualization, solves the problem of insufficient intuitiveness of traditional two-dimensional inspection data, and enhances the ability to perceive and analyze the overall morphology of the board.

[0033] In this embodiment, the moving least squares method is used to smooth the surface of the initial 3D model, and adaptive completion is performed on the missing edge data. Specifically: The moving least squares method is used to smooth the discrete grid points on the surface of the initial 3D model, and the coordinates of any discrete grid point are identified as follows: Select k neighboring points within its neighborhood, denoted as . Construct a weighted least squares objective function: ,in, For measuring neighboring points For discrete grid points The weighting function for smoothing , , These are the fitting coefficients (specifically obtained through the least squares method, used to construct the fitting function for smoothing thickness calculation), and solving them yields the smoothed thickness value. ;in, express The selected neighboring points within the neighborhood range, including coordinates and thickness value

[0034] Identify missing edge data by marking the coordinates of discrete grid points on the edge of the board that are not covered by the sensor as missing data points. Let its nearest valid point be denoted as Calculate the thickness gradient This is used to reflect the thickness variation trend in the x and y directions; and to complete the thickness, the formula is: ; Indicates missing data points The thickness value after adaptive completion.

[0035] It should be noted that a weighted fitting function is constructed using the moving least squares method, and the mesh point thickness h'(x,y) is optimized using the neighborhood point weights and fitting coefficients to eliminate burrs caused by measurement noise in the initial model; for edge missing points... Based on the thickness gradient of nearby effective points Extrapolation completion This ensures that the model surface is smooth and continuous with complete boundaries, providing high-precision 3D data support for subsequent model interaction and construction simulation.

[0036] In this embodiment, a touch screen configured on the control panel enables the visualization and interactive operation of the 3D model of the board material, specifically including: The optimized 3D model is rendered in real time using polygon rendering technology, supporting surface texture and dimension annotation; The user's touch commands are analyzed, and the pose of the 3D model of the board material in the screen coordinate system is updated through a transformation matrix. It also supports users clicking on any location on the model to locate the 3D coordinates using a ray-mapping algorithm. and display the thickness value at that point. and deviation from the standard value ; This indicates the preset standard thickness value of the sheet material; Identify the thickness of the board at any point in the 3D model of the board, compare the board thickness with its preset normal range, and if the board thickness is not within its preset normal range, mark the point as an out-of-tolerance thickness point; connect adjacent out-of-tolerance thickness points to obtain the thickness out-of-tolerance region, and display and mark the deviation value of the thickness out-of-tolerance region and the average deviation value of the region with a preset highlight color.

[0037] It should be noted that this section uses polygon rendering technology to visualize the 3D model, supporting surface texture and dimension annotation, making the shape of the board material intuitively presented; by using a transformation matrix to respond to touch commands, the model's posture can be flexibly adjusted (rotation, scaling, etc.), improving the convenience of interaction; by using ray detection algorithms to accurately locate point coordinates, combined with thickness deviation calculation and out-of-tolerance area identification, quality defects can be quickly marked and highlighted, which not only meets the needs of construction personnel to view the detailed 3D shape of the board material, but also efficiently assists in quality inspection. By quantifying deviations and regional out-of-tolerance marking, it provides intuitive basis for construction quality analysis, problem tracing and repair decisions, strengthens the precise control of board material quality, shortens the conversion link from inspection data to construction application, and improves the level of intelligent management of board material in road and bridge construction.

[0038] In this embodiment, the equipment control and data processing system also includes a construction simulation interface unit, used to achieve compatible interoperability between the 3D model of the slab and external road and bridge construction BIM software, including: The construction simulation interface unit is used to achieve compatible integration between the 3D model of the slab and external road and bridge construction BIM software, including: Format conversion: The optimized 3D model data of the sheet metal (3D vertex coordinates, triangle patch indexes, thickness attributes) is encoded and converted according to the STL or OBJ format specifications. STL format: Stores the normal vector and coordinates of the three vertices of a triangle facet; OBJ format: Stores vertex coordinates, texture coordinates, and patch indexes, and supports additional thickness attribute information; Accuracy Configuration: Provides model simplification options (such as reducing the number of triangular faces), and the export accuracy can be adjusted according to the performance requirements of the BIM software; Data encapsulation: The model file is associated with the unique identifier of the board material (such as the inspection number) and standard dimensional parameters to generate a data package containing complete information. This data package is then transmitted to BIM software through standardized interfaces (such as API and file export) for virtual assembly and collision detection in the construction scenario.

[0039] It should be noted that the construction simulation interface unit enables the 3D model of the slab to be recognized by external BIM software through format conversion (STL / OBJ specifications); it can be configured to adapt to the performance of different BIM software to ensure smooth model import; data encapsulation associates slab identifiers and standard parameters, allowing BIM software to obtain complete information; ultimately, it realizes virtual assembly and collision detection, which helps the construction party to discover construction conflicts in advance, optimize construction plans, integrate slab inspection data into the entire construction process simulation, open up the link between inspection and construction collaboration, improve the digitalization and intelligence level of road and bridge construction, and reduce construction hazards.

[0040] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This embodiment is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the following claims. It should be understood that the present invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A laser-based device for detecting the dimensions of bridge and road construction materials, characterized in that, The device includes a mounting frame (1), a first conveyor belt (2), a second conveyor belt (3), a positioning mechanism, a detection mechanism, a control panel (4), a laser displacement sensor (18), a laser emitter (17), and a device control and data processing system. A power motor (5) is installed on one side of the mounting frame (1). The positioning mechanism is equipped with a positioning platform (12) and a drive motor (11) installed at one end of the positioning platform (12). The control panel (4) is installed on one side of the mounting frame (1). The device control and data processing system operates in the control panel (4) and is communicatively connected to the power motor (5), the drive motor (11), the distance detection component, and the position detection component in the positioning mechanism. It is used to control the operation of the device and collect and process detection data.

2. The laser-based plate size detection device for road and bridge construction as described in claim 1, characterized in that, The conveying mechanism includes a first conveyor belt (2) and a second conveyor belt (3) installed at the front and rear ends of the mounting frame (1); both ends of the first conveyor belt (2) and the second conveyor belt (3) are equipped with drive rollers (8) and multiple support rollers (9) located between the two drive rollers (8); both ends of the drive rollers (8) are equipped with drive wheels on one side of their rotating shafts, and belts (10) are sleeved on the outside of the two drive wheels. The positioning mechanism is installed on the first conveyor belt (2) and is used to position and center the plate. It includes a Z-shaped moving frame (14) that is slidably installed on the positioning table (12) and a bidirectional lead screw (13) connected to the output end of the drive motor (11) through a coupling. The Z-shaped moving frame (14) and the bidirectional lead screw (13) are connected in a transmission. A guide rod (15) is installed on the inner side of the moving frame (14). Multiple rollers (16) are equidistantly rotatably installed on the guide rod (15). The laser emitter (17) is installed on one side of the front end of the guide rod (15). The detection mechanism includes two mounting rods installed on the inner side of the mounting frame (1), and the laser displacement sensors (18) are respectively installed on the mounting rods; the two sets of laser displacement sensors (18) are oriented opposite each other, and the two sets of laser displacement sensors (18) are respectively located at the upper and lower ends of the gap between the first conveyor belt (2) and the second conveyor belt (3); The output end of the power motor (5) is equipped with an active transmission component (6), and driven transmission components (7) mesh on both sides of the active transmission component (6). The two driven transmission components (7) are respectively connected to the shaft of the transmission roller (8) at one end of the first conveyor belt (2) and the second conveyor belt (3) to drive the first conveyor belt (2) and the second conveyor belt (3) to operate synchronously.

3. The laser-based plate size detection device for road and bridge construction as described in claim 2, characterized in that, The equipment control and data processing system includes a conveyor belt synchronization control unit, a positioning drive unit, and a data acquisition and processing unit. The conveyor belt synchronization control unit is used to send control signals to the power motor (5) and control the first conveyor belt (2) and the second conveyor belt (3) to operate synchronously through the transmission parameters of the active transmission component (6) and the driven transmission component (7); The positioning drive unit is used to receive the position signal of the laser emitter (17) and send the drive signal to the drive motor (11) to control the rotation of the bidirectional lead screw (13) so as to realize the centering positioning of the moving frame (14) on the plate. The data acquisition and processing unit is used to acquire the thickness and length data of the plate and the width data of the laser emitter (17) through the laser displacement sensor (18), and calculate the plate parameters after filtering and calibration. The plate parameters include the plate width, thickness and length. The plate parameters are compared with the preset plate standard parameters to determine whether the plate is qualified.

4. The laser-based plate size detection device for road and bridge construction as described in claim 1, characterized in that, The equipment control and data processing system integrates a 3D modeling adaptation module, which includes: The 3D model generation unit is used to construct an initial three-dimensional model of the board based on the calibrated board parameters, using a parametric modeling algorithm. The model optimization unit is used to smooth the surface of the initial 3D model using the moving least squares method and adaptively complete the missing edge data. The model interaction and display unit is used to realize the visualization display and interactive operation of the three-dimensional model of the board material on the touch screen configured on the control panel.

5. The laser-based plate size detection device for road and bridge construction as described in claim 4, characterized in that, Based on the parametric modeling algorithm, an initial 3D model of the board is constructed using the calibrated board parameters, specifically: Coordinate system definition: A three-dimensional coordinate system is established with the starting point O of the plate entering the inspection area as the origin, the length direction as the X-axis, the width direction as the Y-axis, and the thickness direction as the Z-axis; In a three-dimensional coordinate system, the length L and width W of the plate are divided into discrete grid points according to a preset precision. ,in ; Its discrete grid points The formula for calculating the X-coordinate is as follows: The formula for calculating the Y-coordinate is: ,in, , ,in , The preset grid precision; If there are discrete grid points that are not directly measured Then, the thickness values ​​of the measurement points near the point are identified, and the discrete grid point that was not directly measured is solved by the least squares method using the coordinates and thickness values ​​of the nearby measurement points. calibrated plate thickness data Associated with the corresponding grid points, forming 3D vertices. ; By connecting adjacent vertices using a triangulation algorithm, a three-dimensional mesh model of the plate surface is generated, referred to as the initial three-dimensional model. The model boundary lines and dimensioning references are also generated.

6. The laser-based plate size detection device for road and bridge construction as described in claim 4, characterized in that, The surface of the initial 3D model is smoothed using the moving least squares method, and missing edge data is adaptively filled in, specifically as follows: The moving least squares method is used to smooth the discrete grid points on the surface of the initial 3D model, and the coordinates of any discrete grid point are identified as follows: Select k neighboring points within its neighborhood, denoted as . Construct a weighted least squares objective function: ,in, For the weight function, , , The fitting coefficients are used to obtain the smoothed thickness value after solving. ; Identify missing edge data by marking the coordinates of discrete grid points on the edge of the board that are not covered by the sensor as missing data points. Let its nearest valid point be denoted as Calculate the thickness gradient And complete the thickness, the formula is: .

7. The laser-based plate size detection device for road and bridge construction as described in claim 4, characterized in that, The touchscreen on the control panel enables the visualization and interactive operation of the 3D model of the board material, specifically including: The optimized 3D model is rendered in real time using polygon rendering technology, supporting surface texture and dimension annotation; The user's touch commands are analyzed, and the pose of the 3D model of the board material in the screen coordinate system is updated through a transformation matrix. It also supports users clicking on any position of the model to locate the three-dimensional coordinates through the ray detection algorithm, and displays the thickness value of that point and its deviation from the standard value; Identify the thickness of the board at any point in the 3D model of the board, compare the board thickness with its preset normal range, and if the board thickness is not within its preset normal range, mark the point as an out-of-tolerance thickness point; connect adjacent out-of-tolerance thickness points to obtain the thickness out-of-tolerance region, and display and mark the deviation value of the thickness out-of-tolerance region and the average deviation value of the region with a preset highlight color.

8. The laser-based plate size detection device for road and bridge construction as described in claim 4, characterized in that, The equipment control and data processing system also includes a construction simulation interface unit, which is used to achieve compatible integration between the 3D model of the slab and external road and bridge construction BIM software.

9. The laser-based plate size detection device for road and bridge construction as described in claim 8, characterized in that, The construction simulation interface unit includes: Format conversion: The optimized 3D model data of the board material is encoded and converted according to the STL or OBJ format specifications. STL format: Stores the normal vector and coordinates of the three vertices of a triangle facet; OBJ format: Stores 3D vertex coordinates, texture coordinates, and patch indexes, and supports additional thickness attribute information; Precision configuration: Provides options for simplifying the 3D model of the sheet material; Data encapsulation: The model file is associated with the unique identifier of the board material and standard dimensional parameters to generate a data package containing complete information, which is then transmitted to the BIM software through a standardized interface.

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