An automatic detection system and method for internal interface void of steel-concrete composite structure

Abstract

This invention provides an automatic detection system and method for detecting voids in the internal interfaces of reinforced concrete structures, solving the problem that existing reinforced concrete structure detection methods cannot meet the rapid detection needs of complex working curved surfaces. The invention includes a wall-climbing robot and a remote controller, which are wirelessly connected to the wall-climbing robot. The wall-climbing robot includes two hinged base plates, each with two spaced-ahead walking drive devices. Wheels are mounted on the output shafts of the walking drive devices. Electromagnetic adsorption components are fixed to the bottom of both base plates. A central control module and antenna are located on the top of one base plate, while a programmable controller, battery, and electronically controlled impact module are located on the top of the other base plate. In use, by freely changing the angle between the two base plates, the invention can fully cover and move across horizontal, vertical, and curved surfaces, making it suitable for real-time monitoring of large bridges and complex reinforced concrete structures.

Description

Technical Field

[0001] This invention relates to the field of steel-concrete structure testing technology, and in particular to an automatic detection system and method for detecting voids at the internal interfaces of steel-concrete composite structures. Background Technology

[0002] With the rapid development of bridges and large-scale construction projects, steel-tube arch bridges, steel-concrete composite columns, and other steel-concrete structures are widely used in terms of structural load-bearing capacity and durability. These structures, through the combination of steel tubes and concrete, improve overall strength and seismic performance. However, due to complex construction processes and material differences, defects such as voids, cavities, or incomplete interlayer compaction can easily form at the internal interfaces. Once these defects exist, they may lead to localized stress concentration, reducing the overall load-bearing capacity of the structure, and causing cracks, peeling, or even localized failure during long-term service, posing a significant threat to structural safety. Therefore, accurate and efficient detection of voids at the internal interfaces of steel-concrete structures is particularly important.

[0003] In existing testing methods, drilling or cutting sampling can directly obtain information about the internal structure, yielding accurate and reliable results. However, these methods are destructive testing methods and are generally not permitted on in-service structures, especially in critical areas such as bridges, transportation hubs, and high-rise buildings, where significant safety limitations exist. Therefore, in practical engineering, non-destructive testing (NDT) technology has become the preferred approach for detecting voids within reinforced concrete structures. NDT can assess internal defects without damaging the structure, ensuring structural safety and construction continuity.

[0004] Currently, the detection of internal voids in reinforced concrete structures mainly relies on manual handheld inspection equipment. Traditional methods include the tap-microphone method and ultrasonic testing. The ultrasonic method usually requires two opposing sides, and in actual testing, multiple people are needed to complete the inspection. Although the tap-microphone method can detect partial voids through sound vibration characteristics, its detection results are highly dependent on the operator's auditory experience, have limited quantitative capabilities, and signal interpretation still mainly depends on the experience of practitioners. The analysis process is mostly a post-event evaluation and cannot achieve real-time judgment.

[0005] Furthermore, the geometric complexity of reinforced concrete structures further increases the difficulty of inspection. These structures not only have horizontal planes and vertical elevations, but also commonly feature complex curved surfaces such as circular or curved columns and arched beams, making it difficult for handheld inspection equipment to completely cover all areas. During inspection, manual operation is not only time-consuming and labor-intensive, but also poses safety risks associated with working at heights and crossing beams and columns. Additionally, due to differences in subjective experience, the consistency and reliability of repeated inspections are poor. Moreover, existing wall-climbing robots, such as the curtain wall panel stability inspection system and method disclosed in patent application number 202410498908.3, are also ill-suited to the complex working surface environment of circular or curved columns and arched beams. These problems make it difficult for traditional inspection methods to meet the needs of real-time and accurate monitoring of structural health in practical engineering projects.

[0006] Therefore, existing technologies for detecting voids inside reinforced concrete structures still have significant shortcomings. The main problems include the difficulty of existing wall-climbing robots adapting to complex curved working surfaces, while manual handheld detection equipment suffers from low efficiency, high operational risks, reliance on human experience for signal interpretation, and a lack of real-time analysis and visualization capabilities. Particularly in large bridges and high-rise structures, the inability to obtain real-time detection results on-site limits the timeliness of construction quality control and structural safety management. Based on these issues, there is an urgent need to develop an automated, intelligent, real-time analysis, and visualization method and system for detecting voids inside reinforced concrete structures to improve detection accuracy, efficiency, and safety. Summary of the Invention

[0007] To address the problem that existing steel-concrete structure inspection methods cannot meet the rapid inspection requirements of complex working curved surfaces, this invention proposes an automatic inspection system and method for the delamination of internal interfaces in steel-concrete composite structures.

[0008] The technical solution of the present invention is: an automatic detection system for the internal interface void of steel-concrete composite structure, including a wall-climbing robot and a remote controller. The remote controller is wirelessly connected to the wall-climbing robot. The wall-climbing robot includes two hinged base plates. Each base plate is provided with two walking drive devices arranged at intervals. Wheels are mounted on the output shaft of the walking drive devices. One of the base plates has a central control module and an antenna on its top, while the other base plate has a programmable controller, a battery, and an electronically controlled striking module on its top. The base plate has a first through hole that allows the lower end of the electronically controlled striking module to pass through, and the bottom of the base plate has a sound collection component for collecting the striking sound of the electronically controlled striking module. Electromagnetic adsorption components are fixedly installed at the bottom of both base plates. The electromagnetic adsorption components are used to adsorb onto the surface of the steel-concrete structure, and the electromagnetic adsorption components can slide on the surface of the steel-concrete structure as the wall-climbing robot moves. The battery is electrically connected to the controller, central control module, electric tapping module, electromagnetic adsorption component, walking drive device, and sound collection component. The controller is controllably connected to the electric tapping module, electromagnetic adsorption component, walking drive device, and sound collection component. The controller is communicatively connected to the central control module. The central control module is communicatively connected to the antenna. The central control module is wirelessly connected to the remote control via the antenna.

[0009] Preferably, the central control module has a built-in information analysis module and a deep learning discrimination module; The information analysis module is used to perform short-time Fourier transform on the signals collected by the sound collection component to convert the time-domain signals into frequency-domain feature map data; The deep learning discrimination module has a built-in pre-trained MobileNetV2 model. The deep learning discrimination module uses the MobileNetV2 model to classify the frequency domain feature map data in real time to determine whether there is interface void at the measurement point.

[0010] Preferably, the remote control is equipped with a display module, which is used to display the measurement point judgment information transmitted by the central control module.

[0011] Preferably, the electrically controlled striking module includes a first electrically controlled telescopic device, which is connected to the controller. The first electrically controlled telescopic device includes a piston rod, and an electrically controlled rotating assembly is provided at the lower end of the piston rod. The electrically controlled rotating assembly is connected to the controller. A first steel ball, a second steel ball, and a third steel ball for striking are provided at equal intervals on the rotating surface of the electrically controlled rotating assembly, and the diameters of the first steel ball, the second steel ball, and the third steel ball increase sequentially.

[0012] Preferably, the lower end of the piston rod has a mounting slot with a downward opening; The electrically controlled rotating assembly includes a first rotating shaft that is rotatably inserted into a mounting slot. One end of the first rotating shaft is connected to the output shaft of a first motor. The first motor is fixedly mounted on a piston rod. Three connecting rods are fixedly mounted on the side wall of the first rotating shaft and are equidistantly arranged around it. The connecting rods extend radially along the first rotating shaft. When any connecting rod rotates to directly below the first rotating shaft, the end of the connecting rod away from the first rotating shaft extends out of the lower opening of the mounting slot. The first steel ball, the second steel ball, and the third steel ball are each fixedly installed at the end of the three connecting rods away from the first rotating shaft; An electromagnetic brake is mounted on the first rotating shaft. The electromagnetic brake is fixed on the inner wall of the mounting slot and is connected to the controller.

[0013] Preferably, the piston rod has a hollow inner cavity, and a second through hole is opened at the bottom of the piston rod, with the inner cavity and the mounting groove communicating with each other through the second through hole; A second electrically controlled telescopic device is fixedly installed inside the inner cavity. The second electrically controlled telescopic device is connected to the controller. The movable end of the second electrically controlled telescopic device extends through the second through hole into the inner cavity. A positioning plate is fixedly installed on the movable end of the second electrically controlled telescopic device. When any one of the connecting rods rotates to the position directly below the first rotating shaft, the positioning plate can be pushed between the other two connecting rods by the second electrically controlled telescopic device and simultaneously come into contact with the other two connecting rods to restrict the rotation of the connecting rods. When the second electrically controlled telescopic device is in its initial state, the positioning plate is located outside the rotation trajectory of the first, second, and third steel balls.

[0014] Preferably, the electrically controlled rotating assembly is equipped with a rotary encoder for detecting its rotation angle, and the rotary encoder is communicatively connected to the controller.

[0015] Preferably, the electromagnetic adsorption assembly includes a second fixing plate fixedly connected to the bottom of the base plate, the bottom of the second fixing plate being fixedly connected to the upper end of a spring telescopic rod that can extend and retract vertically, the lower end of the spring telescopic rod being connected to the upper end of a ball joint connector, the lower end of the ball joint connector being fixedly connected to the top of the second electromagnet, the second electromagnet being controlled and connected to a controller, and a circular protective magnetic metal plate being fixedly provided at the bottom of the second electromagnet, the periphery of the protective magnetic metal plate being raised obliquely upward to form an annular raised edge.

[0016] Preferably, the bottom of the base plate is provided with an electrically controlled translation component that can move horizontally on its bottom. The electrically controlled translation component and the electrically controlled striking module are located on the same base plate. The electrically controlled translation component is connected to the controller. The bottom of the electrically controlled translation component is provided with a camera component. The camera assembly includes a third motor fixedly mounted at the bottom of the electronically controlled translation assembly. The third motor is connected to the controller. A turntable is fixedly mounted on the output shaft of the third motor. The bottom surface of the turntable is a conical surface that is smaller at the top and larger at the bottom. A camera is fixedly mounted on the conical surface. The camera is connected to the central control module.

[0017] An automatic detection method for the internal interface voids of reinforced concrete composite structures, according to the aforementioned automatic detection system for the internal interface voids of reinforced concrete composite structures, includes the following steps: Step S1, activate the electromagnetic adsorption component, place the wall-climbing robot on the surface of the reinforced concrete structure, and control the wall-climbing robot to move up, down, left, and right using a remote control. When the wall-climbing robot moves on the curved surface of the reinforced concrete structure, the two hinged base plates automatically form an appropriate angle state, realizing normal movement on the curved surface of the reinforced concrete structure in the detection area. During the movement, the voltage of the electromagnetic adsorption component can be controlled by the remote control so that the adsorption force of the wall-climbing robot can be adjusted according to the thickness of the reinforced concrete structure. Step S2: When the wall-climbing robot moves to the measurement point, the electric control knocking module on the wall-climbing robot is controlled by the remote controller to knock on the measurement point, which will stimulate the vibration of the steel-concrete structure. The knocking echo signal is collected in real time by the sound collection component and transmitted to the central control module. When the electronically controlled striking module strikes the measurement point, the operator can switch between the first, second, and third steel balls struck by the electronically controlled striking module on the wall-climbing robot arbitrarily, depending on the thickness of the reinforced concrete structure being measured; or, at the same measurement point, the operator can switch between the first, second, and third steel balls struck by the electronically controlled striking module on the wall-climbing robot in sequence, performing multiple striking measurements. Step S3: The information analysis module in the central control module performs a short-time Fourier transform on the signal collected by the sound collection component to convert the time-domain signal into frequency-domain feature map data. In step S4, the deep learning discrimination module in the central control module performs real-time classification of the frequency domain feature map data using a pre-trained lightweight convolutional neural network MobileNetV2 model to determine whether there is interface void at the measurement point. The detection results of the measurement points are saved in sequence to form a complete detection record. The detection structure is then transmitted to the remote controller in real time via the antenna and displayed on the display component of the remote controller in real time.

[0018] Advantages of the present invention: (1) The present invention can quickly identify and locate the voids in the internal interface of the steel-concrete structure, with high detection efficiency. It can fully cover and move on the horizontal plane, vertical plane and curved surface, and is suitable for real-time monitoring of large bridges and complex steel-concrete structures.

[0019] (2) The present invention can convert the collected time-domain signal of the impact echo into frequency domain feature map data by combining the signal analysis module with the short-time Fourier transform (STFT). Then, the pre-trained MobileNetV2 model built into the deep learning discrimination module is used for fast and intelligent real-time discrimination, which weakens the subjectivity of the inspection personnel in judging the results and their dependence on engineering experience, and achieves strong objectivity of the inspection results. The discrimination results can be wirelessly transmitted to the remote control (mobile phone) for visualization display, so that the health status of the steel-concrete structure can be grasped on site in real time, and the timeliness of construction management and maintenance decisions can be improved. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a top-view structural diagram of the wall-climbing robot in Example 1; Figure 2 This is a top-down view of the wall-climbing robot in Example 1 (cables have been removed). Figure 3 for Figure 2 A schematic diagram of the three-dimensional structure viewed from below; Figure 4 for Figure 2 A schematic diagram of the electronically controlled striking module in the middle; Figure 5 for Figure 4 A schematic diagram of the cross-sectional structure at point AA of the electronically controlled striking module; Figure 6 for Figure 4 Enlarged view of the structure at point B in the image; Figure 7 for Figure 3 A three-dimensional structural diagram of the sound collection component in the image; Figure 8 for Figure 3 A schematic diagram of the planar structure of the electronically controlled translation component and the camera component on it; Figure 9 for Figure 8 A three-dimensional structural diagram of the slider and the camera component on it; Figure 10 for Figure 3 A schematic diagram of the planar structure of the electromagnetic adsorption component in the image; Figure 11 for Figure 10 A three-dimensional structural diagram of the electromagnetic adsorption component in the image; Figure 12 This is a flowchart of the automatic detection method for interface voids in steel-concrete structures in Example 1; Figure 13 A schematic diagram illustrating the use of the wall-climbing robot during a detachment test on the first steel-concrete interface. Figure 14 This is a schematic diagram illustrating the use of the wall-climbing robot in a detachment test at a second steel-concrete interface. Figure 15 A schematic diagram illustrating the use of the wall-climbing robot in a detachment test on a third steel-concrete interface. Figure 16 The spectrum of the interface detachment signal obtained during the detachment experiment of the wall-climbing robot on the steel-concrete interface; Figure 17 The spectrum of interface density signal obtained when the wall-climbing robot was tested in a void-free test on a steel-concrete interface. Figure 18 The graph shows the prediction results of the laboratory test model; In the diagram, 1. Antenna, 2. Cable, 3. Controller, 4. Battery, 5. Central control module, 6. Electric impact module, 7. Electromagnetic adsorption component, 8. Hinge, 9. Base plate, 901. First through hole, 10. Threading slot, 11. Walking drive device, 12. Wheel. 13. Fixing bracket; 14. Sleeve; 1401. First mounting slot; 1402. Limiting slot; 1403. Limiting block; 1404. Second mounting slot; 15. Piston rod; 1501. Mounting slot; 1502. Inner cavity; 16. Permanent magnet; 17. First electromagnet; 18. First rotating shaft; 19. First motor; 20. First motor mounting bracket; 21. Anti-detachment cap; 22. Rotary encoder; 23. Electromagnetic brake; 24. Connecting rod; 25. First steel ball; 26. Second steel ball; 27. Third steel ball; 28. First fixing plate; 29. ​​Second electrically controlled telescopic device; 30. Positioning plate; 31. Fixing ring; 32. Microphone; 33. Slide rail; 34. Slider; 35. Second motor mounting bracket; 36. Second motor; 37. Drive wheel; 38. Third motor; 39. Turntable; 3901. Conical surface; 40. Camera. 41. Second fixed plate; 42. Spring telescopic rod; 43. Ball joint connector; 44. Second electromagnet; 45. Protective magnetic metal plate; 46. Annular warped edge. Detailed Implementation

[0022] 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.

[0023] Example 1: An automatic detection system for the delamination of internal interfaces in steel-concrete composite structures, such as... Figure 1 and Figure 2 As shown, the system includes a wall-climbing robot and a remote control. The remote control and the wall-climbing robot can be wirelessly connected via Bluetooth, Wi-Fi, or 5G signals. In this embodiment, the remote control is a mobile phone with a display. The mobile phone controls the wall-climbing robot through its built-in software. The built-in software of the mobile phone can display the measurement point judgment information transmitted by the central control module 5.

[0024] The wall-climbing robot includes two base plates 9 that are hinged to each other by hinges 8. In this embodiment, the base plates 9 are made of aluminum alloy plates. The base plates 9 have through slots 10 for wires and cables 2 to pass through.

[0025] Each base plate 9 is provided with two walking drive devices 11 arranged at intervals. The output shaft of the walking drive device 11 is fitted with a wheel 12. The walking drive device 11 in this embodiment uses conventional components such as motors for driving wheel rotation. These are existing technologies and not the focus of this invention. Therefore, its structure will not be described in detail in this embodiment.

[0026] like Figure 1 and Figure 2 As shown, a central control module 5 and an antenna 1 are located on the top of one of the base plates 9.

[0027] In this embodiment, the central control module 5 has a built-in information analysis module and a deep learning discrimination module to realize real-time processing of the measured data. Specifically: The information analysis module is used to perform short-time Fourier transform on the signals collected by the sound collection component to convert the time-domain signals into frequency-domain feature map data. In this embodiment, the parameters for performing short-time Fourier transform on the collected signals are set as follows: sampling rate Fs = 44100 Hz, window length nperseg = 512, window overlap rate noverlap = 95%, and fast Fourier transform points nfft = 2048. The deep learning discrimination module incorporates a pre-trained lightweight convolutional neural network model, MobileNetV2. This module uses the MobileNetV2 model to classify frequency domain feature map data in real time to determine if interface gaps exist at measurement points. For a similar pre-training method for the MobileNetV2 model, please refer to the paper "Real-time Crack Classification of Wall-Climbing Robots Based on MobileNetV2," published on October 13, 2023, in Volume 1911 of *Computer and Information Science Communications*. This pre-training method is existing technology, and its details will not be elaborated further.

[0028] like Figure 2 and Figure 3 As shown, the top of another base plate 9 is provided with a programmable controller 3, a battery 4 and an electronically controlled striking module 6. In this embodiment, the controller 3 is a programmable PLC controller.

[0029] like Figure 3 As shown, the base plate 9 has a first through hole 901 through which the lower end of the electronically controlled striking module 6 can pass. In this embodiment, as... Figure 4 and Figure 5 As shown, the electrically controlled striking module 6 includes a fixed frame 13 fixed on the base plate 9. A first electrically controlled telescopic device is mounted on the fixed frame 13. In this embodiment, the first electrically controlled telescopic device is an electromagnetically controlled telescopic rod structure. In other embodiments, it can be replaced by an electric push rod, a cylinder, or other telescopic device. In this embodiment, as... Figure 5 As shown, the first electrically controlled telescopic device includes a sleeve 14 passing through a fixed frame 13. The sleeve 14 has a second mounting slot 1404 and a first mounting slot 1401 spaced apart vertically. The bottom of the second mounting slot 1404 has a connecting hole that communicates with the first mounting slot 1401. A first electromagnet 17 is fixedly installed in the second mounting slot 1404. The first electromagnet 17 is connected to a controller 3, which can adjust the voltage and current direction of the electromagnet 17 to adjust its magnetic force and pole direction. A piston rod 15 is movably inserted into the first mounting slot 1401. A permanent magnet 16 is fixedly installed on the top of the piston rod 15, and the top of the permanent magnet 16 can pass through the connecting hole and contact the electromagnet 17.

[0030] A limiting groove 1402 extending in the vertical direction is provided on the side wall of the first mounting slot 1401. A limiting block 1403 that can slide back and forth along its length direction is provided in the limiting groove 1402. The limiting block 1403 is fixedly provided on the side wall of the piston rod 15. The limiting block 1403 and the limiting groove 1402 cooperate to limit the stroke length of the piston rod 15 and prevent the piston rod 15 from coming out of the sleeve 14.

[0031] The lower end of the piston rod 15 is equipped with an electrically controlled rotation assembly. Specifically, in this embodiment, as shown... Figure 6 As shown, the lower end of the piston rod 15 has a mounting slot 1501 with a lower opening. The electrically controlled rotating assembly includes a first rotating shaft 18 that rotatably passes through the mounting slot 1501. One end of the first rotating shaft 18 is connected to the output shaft of a first motor 19, and the first motor 19 is controlled by a controller 3. A first motor mounting bracket 20 is fixedly mounted on the piston rod 15, and the first motor 19 is fixedly mounted on the first motor mounting bracket 20. Three connecting rods 24 are fixedly mounted on the side wall of the first rotating shaft 18, equidistant from it. The connecting rods 24 extend radially along the first rotating shaft 18. When any connecting rod 24 rotates to directly below the first rotating shaft 18, the end of the connecting rod 24 away from the first rotating shaft 18 extends out of the lower opening of the mounting slot 1501. A first steel ball 25, a second steel ball 26, and a third steel ball 27 are fixedly mounted on the ends of the three connecting rods 24 away from the first rotating shaft 18, and the diameters of the first steel ball 25, the second steel ball 26, and the third steel ball 27 increase sequentially. By selecting steel balls of different diameters, steel-concrete structures of different thicknesses can be tested.

[0032] In this embodiment, the diameter of the first steel ball 25 is 3mm, and the depth of the structure that can be measured is about 70cm; the diameter of the second steel ball 26 is 6mm, and the depth that can be measured is about 100cm; and the diameter of the third steel ball 27 is 9mm, and the depth that can be measured is about 300cm. This data is cited from the paper "Ultrasonic Method and Impact Echo Method for Detecting Reinforced Concrete Beam-Column Joints" in the Journal of Beijing University of Science and Technology.

[0033] To prevent the connecting rod 24 from rotating during impact, which could cause the impact point of the steel ball to shift, such as... Figure 6 As shown, an electromagnetic brake 23 is mounted on the first rotating shaft 18. The electromagnetic brake 23 is fixed on the inner side wall of the mounting slot 1501 and is connected to the controller 3.

[0034] Furthermore, to enhance the anti-deviation effect of the connecting rod 24 during impact, in this embodiment, such as Figure 5 and Figure 6 As shown, the piston rod 15 has a hollow inner cavity 1502 inside. The bottom of the piston rod 15 has a second through hole that is open from top to bottom. The inner cavity 1502 and the mounting slot 1501 are connected to each other through the second through hole. A first fixing plate 28 is fixedly installed inside the inner cavity 1502. A second electrically controlled telescopic device 29 is fixedly installed at the bottom of the first fixing plate 28. In this embodiment, the second electrically controlled telescopic device 29 is an electric push rod. The second electrically controlled telescopic device 29 is connected to the controller 3. The movable end of the second electrically controlled telescopic device 29 moves through the second through hole and extends into the inner cavity 1502. A positioning plate 30 is fixedly installed on the movable end of the second electrically controlled telescopic device 29.

[0035] In use, when any one of the connecting rods 24 rotates to the position directly below the first rotating shaft 18, the positioning plate 30 can be pushed between the other two connecting rods 24 by the second electrically controlled telescopic device 29 and simultaneously come into contact with the other two connecting rods 24 to restrict the rotation of the connecting rods 24; when the second electrically controlled telescopic device 29 is in the initial state, the positioning plate 30 is located outside the rotation trajectory of the first steel ball 25, the second steel ball 26 and the third steel ball 27 to avoid affecting the rotation and replacement of the steel balls.

[0036] like Figure 6 As shown, a section of the first rotating shaft 18 away from the first motor 19 is fitted with an anti-detachment cap 21 to prevent it from falling off. A rotary encoder 22 is fixedly mounted on the side of the anti-detachment cap 21 away from the first rotating shaft 18. The rotary encoder 22 is communicatively connected to the controller 3. The rotary encoder 22 is used to detect the rotation angle of the first motor 19 and the first rotating shaft 18, so that the controller 3 can accurately control the rotation angle of the first motor 19, so that when the steel ball is replaced, the steel ball can be accurately rotated to be directly above the measured point.

[0037] The bottom of the base plate 9 is equipped with a sound collection component for collecting the sound of the electronically controlled striking module 6. In order to make the collected echo signal more accurate, in this embodiment, such as... Figure 3 and Figure 7 As shown, the sound collection assembly includes a fixing ring 31 that surrounds the piston rod 15 and is fixed to the bottom of the base plate 9. Three microphones 32 that are equidistantly spaced around the piston rod 15 are fixed to the bottom of the fixing ring 31.

[0038] Two electromagnetic adsorption components 7, spaced apart front to back, are fixedly installed on the bottom of each of the two base plates 9. These components are used to adhere to the surface of the reinforced concrete structure and can slide on the surface as the climbing robot moves. Specifically, in this embodiment, as... Figure 3 , Figure 10 and Figure 11 As shown, the electromagnetic adsorption assembly 7 includes a second fixing plate 41 fixedly connected to the bottom of the base plate 9. The bottom of the second fixing plate 41 is fixedly connected to the upper end of a spring telescopic rod 41 that can extend and retract vertically. The lower end of the spring telescopic rod 41 is connected to the upper end of a ball joint connector 43. The lower end of the ball joint connector 43 is fixedly connected to the top of a second electromagnet 44. The second electromagnet 44 is controlled and connected to the controller 3. A circular protective magnetic metal plate 45 is fixedly provided at the bottom of the second electromagnet 44. The periphery of the protective magnetic metal plate 45 is raised obliquely upward to form an annular raised edge 46.

[0039] When in use, when encountering a low step-like structure on the surface of the reinforced concrete structure, the controller 3 can temporarily de-energize the electromagnetic adsorption component 7 at that location, and the spring telescopic rod 41 will automatically reset and pull up the second electromagnet 44 and the protective magnetic metal plate 45. The electromagnetic adsorption components 7 at other locations will continue to be energized so that the wall-climbing robot continues to adhere to the surface of the reinforced concrete structure. The annular raised edge 46 around the protective magnetic metal plate 45 makes it easier for the wall-climbing robot to smoothly cross the step.

[0040] In order to allow for a direct observation of the reinforced concrete structure surface traversed by the wall-climbing robot during its movement, in this embodiment, as follows: Figure 3 As shown, the bottom of the base plate 9 is provided with an electrically controlled translation component that can move horizontally on its bottom. The electrically controlled translation component and the electrically controlled striking module 6 are located on the same base plate 9. The electrically controlled translation component is connected to the controller 3. The bottom of the electrically controlled translation component is provided with a camera component.

[0041] Specifically, such as Figure 8 and Figure 9 As shown, the electrically controlled translation component includes a slide rail 33 fixedly mounted on the bottom of the base plate 9, a slider 34 slidably mounted on the slide rail 33, a second motor mounting bracket 35 fixedly mounted on one side of the slider 34, a second motor 36 fixedly mounted on the bottom of the second motor mounting bracket 35, the second motor 36 being controlled and connected to the controller 3, a drive wheel 37 fixedly mounted on the output shaft of the second motor 36, the peripheral side of the drive wheel 37 rolling contact with the surface of the slide rail 33, and the second motor 36 driving the drive wheel 37 to roll along the slide rail 33, thereby driving the slider 34 to reciprocate along the slide rail 33.

[0042] The camera assembly includes a third motor 38 fixedly mounted on the bottom of the slider 34. The third motor 38 is connected to the controller 3. A turntable 39 is fixedly mounted on the output shaft of the third motor 38. To allow the camera 40 to obtain a wider field of view, such as... Figure 9 As shown, the bottom surface of the turntable 39 is a conical surface 3901 with a smaller top and a larger bottom. A camera 40 is fixedly installed on the conical surface 3901, and the camera 40 is communicatively connected to the central control module 5.

[0043] Battery 4 is electrically connected to controller 3, central control module 5, electronically controlled knocking module 6, electromagnetic adsorption component 7, walking drive device 11, and sound collection component via wires.

[0044] The controller 3 is connected to the electric impact module 6, the electromagnetic adsorption component 7, the walking drive device 11, and the sound collection component through multiple cables 2 to achieve signal transmission and control. The controller 3 and the central control module 5 are also connected to achieve stable wired communication through a single cable 2.

[0045] The central control module 5 is connected to the antenna 1 for communication, and the central control module 5 is connected to the remote control (in this embodiment, a mobile phone) wirelessly via the antenna 1.

[0046] An automatic detection method for interface voids in steel-concrete composite structures, based on the aforementioned automatic detection system for interface voids in steel-concrete composite structures, such as... Figure 12 As shown, the procedure includes the following steps: Step S1, activate the electromagnetic adsorption component 7, place the wall-climbing robot on the surface of the reinforced concrete structure, and control the wall-climbing robot to move up, down, left, and right using a remote control. When the wall-climbing robot moves on the curved surface of the reinforced concrete structure, as... Figure 13 , Figure 14 , Figure 15 As shown, the two hinged base plates 9 automatically form an appropriate angle, enabling normal movement on the surface of the steel-concrete structure with a curved shape in the detection area. During the movement, the voltage of the electromagnetic adsorption component 7 can be controlled by a remote control so that the adsorption force of the wall-climbing robot can be adjusted according to the thickness of the steel-concrete structure.

[0047] Step S2: When the wall-climbing robot moves to the measurement point, the electric control knocking module 6 on the wall-climbing robot is controlled by the remote controller to knock on the measurement point, which will stimulate the vibration of the steel-concrete structure. The knocking echo signal is collected in real time by the sound collection component and transmitted to the central control module 5. When the electrically controlled striking module 6 strikes the measurement point, the operator can control the first steel ball 25, the second steel ball 26, and the third steel ball 27 on the electrically controlled striking module 6 on the wall-climbing robot to switch arbitrarily according to the thickness of the reinforced concrete structure being measured; or, at the same measurement point, the operator can control the first steel ball 25, the second steel ball 26, and the third steel ball 27 on the electrically controlled striking module 6 on the wall-climbing robot to switch sequentially via remote control, performing multiple striking measurements to meet different testing requirements. The specific switching methods for the first steel ball 25, the second steel ball 26, and the third steel ball 27 can be found in the structural description of the electrically controlled striking module 6 described above.

[0048] Step S3: The information analysis module in the central control module 5 performs a short-time Fourier transform on the signal acquired by the sound collection component. The parameters for performing the short-time Fourier transform on the acquired signal are set as follows: sampling rate Fs = 44100Hz, window length nperseg = 512, window overlap ratio nooverlap = 95%, and fast Fourier transform points nfft = 2048, in order to convert the time-domain signal into frequency-domain feature map data. The frequency-domain feature map data obtained in the experiment is as follows. Figure 16 As shown.

[0049] In step S4, the deep learning discrimination module in the central control module 5 performs real-time classification of the frequency domain feature map data using a pre-trained lightweight convolutional neural network MobileNetV2 model to determine whether there is interface void at the measurement point. The detection results of the measurement points are saved in sequence to form a complete detection record. The detection structure is then transmitted to the remote controller in real time through antenna 1 and displayed in real time on the display component of the remote controller, realizing fast, intelligent and visualized detection result output.

[0050] During the testing experiment, 225 signals were collected at the pre-defined empty area of ​​the interface, and 322 signals were collected at the dense area of ​​the interface. A pre-trained lightweight convolutional neural network MobileNetV2 model was used to perform batch prediction of the echo signals. The spectrum diagram of the dense interface signal obtained in the experiment is shown below. Figure 17 As shown, the classification prediction results of the MobileNetV2 model on the frequency domain feature map data obtained in the experiment are as follows: Figure 18 As shown, the recognition accuracy for interface voids and interface solids reached 98.22% and 98.14% respectively, and the overall prediction accuracy of the MobileNetV2 model was 98.18%, indicating high test precision.

[0051] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims and not by the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. An automatic detection system for the internal interface voids of reinforced concrete composite structures, comprising a wall-climbing robot and a remote controller, wherein the remote controller is wirelessly connected to the wall-climbing robot for remote control, characterized in that: The wall-climbing robot includes two hinged base plates (9), each base plate (9) is provided with two walking drive devices (11) arranged in a front-to-back interval, and wheels (12) are mounted on the output shaft of the walking drive device (11). One of the base plates (9) has a central control module (5) and an antenna (1) on its top, and the other base plate (9) has a programmable controller (3), a battery (4) and an electronically controlled striking module (6) on its top. The base plate (9) has a first through hole (901) that allows the lower end of the electronically controlled striking module (6) to pass through. The bottom of the base plate (9) has a sound collection component for collecting the striking sound of the electronically controlled striking module (6). Electromagnetic adsorption components (7) are fixedly provided at the bottom of both base plates (9). The electromagnetic adsorption components (7) are used to adsorb onto the surface of the steel-concrete structure, and the electromagnetic adsorption components (7) can slide on the surface of the steel-concrete structure as the wall-climbing robot moves. The battery (4) is electrically connected to the controller (3), the central control module (5), the electric knocking module (6), the electromagnetic adsorption component (7), the walking drive device (11), and the sound collection component, respectively. The controller (3) is controlled to the electric knocking module (6), the electromagnetic adsorption component (7), the walking drive device (11), and the sound collection component, respectively. The controller (3) is communicatively connected to the central control module (5). The central control module (5) is communicatively connected to the antenna (1). The central control module (5) is wirelessly connected to the remote control signal through the antenna (1).

2. The automatic detection system for interface voids in reinforced concrete composite structures as described in claim 1, characterized in that: The central control module (5) has a built-in information analysis module and a deep learning discrimination module; The information analysis module is used to perform short-time Fourier transform on the signals collected by the sound collection component to convert the time-domain signals into frequency-domain feature map data; The deep learning discrimination module has a built-in pre-trained MobileNetV2 model. The deep learning discrimination module uses the MobileNetV2 model to classify the frequency domain feature map data in real time to determine whether there is interface void at the measurement point.

3. The automatic detection system for interface voids in reinforced concrete composite structures as described in claim 2, characterized in that: The remote control is equipped with a display module, which is used to display the measurement point judgment information transmitted by the central control module (5).

4. The automatic detection system for the internal interface voids of reinforced concrete composite structures as described in claim 1, characterized in that: The electrically controlled striking module (6) includes a first electrically controlled telescopic device, which is controlled and connected to the controller (3). The first electrically controlled telescopic device includes a piston rod (15), and an electrically controlled rotating assembly is provided at the lower end of the piston rod (15). The electrically controlled rotating assembly is controlled and connected to the controller (3). The rotating surface of the electrically controlled rotating assembly is provided with a first steel ball (25), a second steel ball (26), and a third steel ball (27) for striking at equal intervals. The diameters of the first steel ball (25), the second steel ball (26), and the third steel ball (27) increase sequentially.

5. The automatic detection system for interface voids in steel-concrete composite structures as described in claim 4, characterized in that: The lower end of the piston rod (15) is provided with a mounting slot (1501) with a lower opening. The electrically controlled rotating assembly includes a first rotating shaft (18) that is rotatably inserted into the mounting slot (1501). One end of the first rotating shaft (18) is connected to the output shaft of a first motor (19). The first motor (19) is fixedly mounted on a piston rod (15). Three connecting rods (24) are fixedly mounted on the side wall of the first rotating shaft (18) and are equidistant from it. The connecting rods (24) extend radially along the first rotating shaft (18). When any connecting rod (24) rotates to the position directly below the first rotating shaft (18), the end of the connecting rod (24) away from the first rotating shaft (18) extends out of the lower opening of the mounting slot (1501). The first steel ball (25), the second steel ball (26) and the third steel ball (27) are each fixedly mounted on one end of the three connecting rods (24) away from the first rotating shaft (18); An electromagnetic brake (23) is mounted on the first rotating shaft (18). The electromagnetic brake (23) is fixed on the inner side wall of the mounting slot (1501). The electromagnetic brake (23) is connected to the controller (3).

6. The automatic detection system for the internal interface voids of a steel-concrete composite structure as described in claim 5, characterized in that: The piston rod (15) has a hollow inner cavity (1502) inside, and a second through hole is opened at the bottom of the piston rod (15). The inner cavity (1502) and the mounting slot (1501) are connected to each other through the second through hole. A second electrically controlled telescopic device (29) is fixedly provided inside the inner cavity (1502). The second electrically controlled telescopic device (29) is connected to the controller (3). The movable end of the second electrically controlled telescopic device (29) extends through the second through hole into the inner cavity (1502). The movable end of the second electrically controlled telescopic device (29) is fixedly provided with a positioning plate (30). When any one of the connecting rods (24) rotates to the position directly below the first rotating shaft (18), the positioning plate (30) can be pushed between the other two connecting rods (24) by the second electronically controlled telescopic device (29) and simultaneously abut against the other two connecting rods (24) to restrict the rotation of the connecting rods (24); When the second electrically controlled telescopic device (29) is in the initial state, the positioning plate (30) is located outside the rotation trajectory of the first steel ball (25), the second steel ball (26) and the third steel ball (27).

7. The automatic detection system for interface voids in steel-concrete composite structures as described in claim 4, characterized in that: The electrically controlled rotating assembly is equipped with a rotary encoder (22) for detecting its rotation angle, and the rotary encoder (22) is connected to the controller (3) for communication.

8. The automatic detection system for the internal interface voids of a steel-concrete composite structure as described in claim 1, characterized in that: The electromagnetic adsorption assembly (7) includes a second fixing plate (41) fixedly connected to the bottom of the base plate (9). The bottom of the second fixing plate (41) is fixedly connected to the upper end of a spring telescopic rod (41) that can extend and retract vertically. The lower end of the spring telescopic rod (41) is connected to the upper end of a ball joint connector (43). The lower end of the ball joint connector (43) is fixedly connected to the top of a second electromagnet (44). The second electromagnet (44) is controlled by a controller (3). A circular protective magnetic metal plate (45) is fixedly provided at the bottom of the second electromagnet (44). The periphery of the protective magnetic metal plate (45) is raised obliquely upward to form an annular raised edge (46).

9. The automatic detection system for interface voids in reinforced concrete composite structures as described in claim 1, characterized in that: The bottom of the base plate (9) is provided with an electrically controlled translation component that can move horizontally on its bottom. The electrically controlled translation component and the electrically controlled striking module (6) are located on the same base plate (9). The electrically controlled translation component is connected to the controller (3). The bottom of the electrically controlled translation component is provided with a camera component. The camera assembly includes a third motor (38) fixedly mounted on the bottom of the electronically controlled translation assembly. The third motor (38) is connected to the controller (3). A turntable (39) is fixedly mounted on the output shaft of the third motor (38). The bottom surface of the turntable (39) is a conical surface (3901) that is smaller at the top and larger at the bottom. A camera (40) is fixedly mounted on the conical surface (3901). The camera (40) is connected to the central control module (5) for communication.

10. An automatic detection method for interface voids in steel-concrete composite structures, and an automatic detection system for interface voids in steel-concrete composite structures according to claims 1-9, characterized in that, Includes the following steps: Step S1: Activate the electromagnetic adsorption component (7), place the wall-climbing robot on the surface of the steel-concrete structure, and control the wall-climbing robot to move up, down, left, and right using the remote control. When the wall-climbing robot moves on the curved surface of the steel-concrete structure, the two hinged base plates (9) automatically form an appropriate angle state, so as to realize normal movement on the surface of the steel-concrete structure with a curved shape in the detection area. During the movement, the voltage of the electromagnetic adsorption component (7) can be controlled by the remote control so that the adsorption force of the wall-climbing robot can be adjusted according to the thickness of the steel-concrete structure. Step S2: When the wall-climbing robot moves to the measurement point, the electric control knocking module (6) on the wall-climbing robot is controlled by the remote controller to knock on the measurement point, which excites the vibration of the steel-concrete structure. The knocking echo signal is collected in real time by the sound collection component and transmitted to the central control module (5). When the electronically controlled striking module (6) strikes the measurement point, the operator can switch between the first steel ball (25), the second steel ball (26), and the third steel ball (27) struck by the electronically controlled striking module (6) on the wall-climbing robot arbitrarily according to the thickness of the steel-concrete structure being measured; or, at the same measurement point, the operator can switch between the first steel ball (25), the second steel ball (26), and the third steel ball (27) struck by the electronically controlled striking module (6) on the wall-climbing robot in sequence by the remote control to perform multiple striking measurements; Step S3, the information analysis module in the central control module (5) performs a short-time Fourier transform on the signal collected by the sound collection component to convert the time domain signal into frequency domain feature map data; In step S4, the deep learning discrimination module in the central control module (5) performs real-time classification of the frequency domain feature map data through the pre-trained lightweight convolutional neural network MobileNetV2 model to determine whether there is interface void at the measurement point. The detection results of the measurement point are saved in sequence to form a complete detection record. The detection structure is transmitted to the remote controller in real time through the antenna (1) and displayed in real time on the display component of the remote controller.

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