Intelligent detection equipment for old pavement cracks and use method

Abstract

The invention provides intelligent detection equipment for old pavement cracks and a use method, and belongs to the technical field of intelligent detection equipment for pavement cracks. Comprising a road surface moving assembly, and laser radar scanning assemblies penetrate through the edges of the two sides of the center of the top surface of the road surface moving assembly correspondingly. According to the invention, a wireless remote control drive is arranged in the pavement moving assembly structure, so that the moving direction of the pavement moving assembly can be controlled through the wireless remote control drive by using a remote controller; the detection equipment can be moved by two methods of manually pushing or pulling the road surface moving assembly to adjust the moving direction by manually holding the handle assembly; in addition, by combining two technologies of laser radar scanning and ultrasonic crack depth detection, a modeling graph can be better generated in real time while cracks are detected, and convenience is brought to follow-up workers to use the modeling graph and depth data to adopt corresponding remedial measures in advance during maintenance.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent detection equipment for pavement cracks, and in particular to an intelligent detection equipment for cracks in old pavement and a method for using the same. Background Art

[0002] With the continuous improvement of highway infrastructure, the transportation efficiency and transportation capacity of highways are also constantly improving. The increase in highway mileage and highway transportation capacity has brought about an unavoidable problem: highway maintenance. Pavement crack identification is crucial to highway maintenance. Cracks are one of the earliest forms of pavement diseases. Only by maintaining them in the early stage of cracks can the service life of the highway be effectively improved. Therefore, the pavement crack detection and identification system is of great significance to improving highway quality. For this reason, when encountering cracks, it is necessary to check the size of the cracks to facilitate their repair and reduce the damage caused to them in the later stage.

[0003] In actual engineering application scenarios, due to the complexity of the road background (such as interference from shadows, stains, markings, repairs, etc.) and the diversity of crack types (such as light-colored cracks, fuzzy cracks, moist cracks, cracks, etc.), shallow convolutional neural networks have poor ability to express crack features under complex road backgrounds, and are often prone to missed detection of fuzzy cracks. Due to interference factors such as stains and markings, false detections may also occur.

[0004] Therefore, ultrasound and lidar are used to directly scan the ground, penetrate solids and air, and quickly calculate the depth of the cracks to determine whether it can affect the normal use of the road surface. The existing lidar scanning system can be used to quickly collect three-dimensional modeling of the road surface, which is convenient for subsequent maintenance and detection. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an intelligent detection device for cracks in old pavement and a method for use to solve the complexity of the existing pavement background and the diversity of crack types. Shallow convolutional neural networks have poor ability to express crack characteristics under complex pavement backgrounds, and are often prone to missed detection of fuzzy cracks. Due to interference factors such as stains and markings, misdetection problems may also occur.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] An intelligent detection device for cracks in old pavement, comprising a pavement moving component, wherein laser radar scanning components are respectively passed through the edges on both sides of the center of the top surface of the pavement moving component, ultrasonic crack detection components are respectively provided on both sides of the top surface of the pavement moving component near the front end edge, a handle assembly is provided at the rear end edge of the top surface of the pavement moving component, and the top surface of the pavement moving component is covered with a shell assembly, the number of the laser radar scanning components is two, the number of the ultrasonic crack detection components is two, one of the ultrasonic crack detection components is an ultrasonic transmitter, and the other of the ultrasonic crack detection components is an ultrasonic receiver.

[0008] Optionally, the road surface moving component includes a base plate, and instrument mounting holes are respectively opened at the center of the top surface of the base plate near the left and right edges, and radio remote control drives are respectively provided at the edges of the front and rear ends of the bottom surface of the base plate.

[0009] Optionally, the left and right ends of each of the radio remote-controlled drivable parts are respectively covered with wheel shock absorbers, and one end of each of the wheel shock absorbers is connected to a road wheel.

[0010] Optionally, the handle assembly includes a rotating drum mounting base, a damping shaft is provided on the top surface of the rotating drum mounting base, and a mounting screw hole is provided at the center of the top surface of the damping shaft.

[0011] Optionally, a threaded mounting rod is provided inside the mounting screw hole, a main fixing rod is provided on the top of the threaded mounting rod, a rotating shaft is provided on the top of the main fixing rod, and an elliptical handle runs through the inside of the rotating shaft.

[0012] Optionally, the outer shell assembly includes an outer protective shell, a peripheral surveillance camera is provided at the center of the top surface of the outer protective shell, and a plurality of tool plug-ins are provided in a matrix form on the left and right side surfaces of the outer protective shell.

[0013] Optionally, a front headlight is provided at the center of the front end surface of the outer protective shell, and a crash barrier is covered at the center of the front end surface of the outer protective shell near the bottom edge.

[0014] Optionally, the operating principle of the laser radar scanning component is to use a laser as an emitting light source and an active remote sensing device using photoelectric detection technology. The laser radar is an advanced detection method that combines laser technology with modern photoelectric detection technology. It is composed of a transmitting system, a receiving system, an information processing system, and the like. The transmitting system is composed of various forms of lasers, such as carbon dioxide lasers, neodymium-doped yttrium aluminum garnet lasers, semiconductor lasers, and wavelength-tunable solid lasers and optical beam expansion units; the receiving system uses a telescope and various forms of photoelectric detectors, such as photomultiplier tubes, semiconductor photodiodes, avalanche photodiodes, infrared and visible light multi-element detection devices, etc. The laser radar adopts a pulse or continuous wave working mode. The detection method can be divided into Mie scattering, Rayleigh scattering, Raman scattering, Brillouin scattering, fluorescence, Doppler and other laser radars according to different detection principles.

[0015] Optionally, the principle of using the ultrasonic wave to detect cracks is to first assume that the crack is an isosceles triangle. When the ultrasonic wave emitted by the transmitter propagates in the medium, there are both longitudinal waves and transverse waves. The speed of the longitudinal wave is greater than the speed of the transverse wave. The transmitter and the receiver are symmetrical. The angle of transmission of the elastic wave in the two media is determined by the wave speed. The route of ultrasonic wave propagation in the air is parallel to the horizontal direction. When the ultrasonic wave is emitted from the transmitter, the angle with the horizontal direction is θ, and the angle of the crack is 2θ. After this ultrasonic wave is transmitted into the air, the direction is parallel to the horizontal direction. The transmission law of one medium transmitting into another medium is obtained: V 气 is the speed of ultrasonic wave in dirty air, m / s, which can be solved as follows: V solid is in the range of 3000~5000m / s. Different solid media have different ultrasonic propagation speeds. Take an average value V 固 =4000m / s, the propagation speed of ultrasonic wave in gas V 气 is 340m / s. On this basis, the function graph of θ1 with respect to θ is given by The value range of θ is (0,4.876 0 ), it can be concluded that when the crack angle 2θ is greater than 9.752 0 When , there will be no θ1. The ultrasonic wave emitted by the transmitter cannot return to the receiver after entering the air between the cracks. Therefore, θ is a constant, so θ1 is uniquely determined. By taking different distances between the transmitter and the receiver, we can obtain different ultrasonic propagation paths. According to the ultrasonic path diagram, when L gradually increases to L%, the ultrasonic wave that enters the air and returns to the receiver has reached the maximum L. The propagation at this time is the same as the classical propagation path. Therefore, when actually measuring, the distance between the instruments should be set to When the ultrasonic wave is transmitted into the crack, it will return to the receiver, thus obtaining the depth of the crack.

[0016] A method for using an intelligent detection device for cracks in old pavement, comprising the following steps:

[0017] Step 1: First, place the whole device on the roadside. You can choose to use the remote control to remotely control the moving direction of the road moving component, or you can choose to manually hold the handle component to push or pull the road moving component to adjust the moving direction;

[0018] Step 2: While the pavement moving component is moving, the laser radar scanning component and the ultrasonic crack detection component can be started to scan the front and bottom ground to detect whether there are cracks on the pavement and the depth of the cracks. The ultrasonic crack detection component is placed at the front end to first scan the ground to detect the crack depth and whether there are cracks. Then, the laser radar scanning component at the rear is used to scan the ground and transmit the data to the background. Existing technology can be used to generate three-dimensional modeling diagrams in real time, which is convenient for subsequent staff to use.

[0019] Compared with the prior art, the present invention has at least the following beneficial effects:

[0020] In the above scheme, by setting up a wire-free remote control drive in the structure of the road surface moving component, the moving direction of the road surface moving component can be remotely controlled by a remote control or a radio remote control drive. You can also choose to manually hold the handle component to push or pull the road surface moving component to adjust the moving direction. These two methods are used to move the detection equipment. In addition, the combination of laser radar scanning and ultrasonic detection of crack depth can better generate modeling diagrams in real time while detecting cracks, which is convenient for subsequent staff to use modeling diagrams and depth data in advance to adopt corresponding remedial measures when performing maintenance. Finally, the advantages of using laser radar are: high resolution, good concealment, strong anti-active interference ability, good low-altitude detection performance, small size, and light weight, which can cooperate well with detection.

[0021] By installing surrounding surveillance cameras within the shell component structure, the surrounding situation can be monitored, allowing remote operators to view the surrounding environment in real time, and the front lights can illuminate the road ahead when working at night. The role of the anti-collision guardrail is to reduce the degree of impact in front if the remote operator causes a collision due to improper operation, and to protect the internal devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings, which are incorporated herein and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, further serve to explain the principles of the invention and to enable those skilled in the relevant art to make and use the invention.

[0023] Figure 1 This is a schematic diagram of the three-dimensional structure of the old road crack intelligent detection equipment;

[0024] Figure 2 This is a schematic diagram of the internal three-dimensional structure of the old road crack intelligent detection equipment;

[0025] Figure 3 This is a schematic diagram of the structure of the ultrasonic crack detection component;

[0026] Figure 4 This is a schematic diagram of the structure of the laser radar scanning component;

[0027] Figure 5 Schematic diagram of ultrasonic wave propagation path;

[0028] Figure 6 It is a schematic diagram of the function graph of θ1 with respect to θ;

[0029] Figure 7 is a schematic diagram of multiple ultrasonic wave propagation paths;

[0030] Figure 8 It is a schematic diagram of the structure of the housing component;

[0031] Fig. 9 It is a schematic diagram of the structure of the road surface moving component;

[0032] Fig.10 This is a schematic diagram of the handlebar assembly structure.

[0033] [reference numerals]

[0034] 1. Road moving assembly; 101. Bottom plate; 102. Instrument mounting hole; 103. Radio remote control drive; 104. Wheel shock absorption; 105. Road wheel; 2. LiDAR scanning assembly; 3. Ultrasonic crack detection assembly; 4. Handle assembly; 401. Drum mounting base; 402. Damping shaft; 403. Mounting screw hole; 404. Threaded mounting rod; 405. Main fixing rod; 406. Shaft; 407. Oval handle; 5. Shell assembly; 501. Outer protective shell; 502. Surrounding monitoring camera; 503. Tool plug plate; 504. Front headlight; 505. Anti-collision guardrail.

[0035] As shown in the figure, in order to clearly implement the structure of the embodiment of the present invention, specific structures and devices are marked in the figure, but this is only for illustrative purposes and is not intended to limit the present invention to the specific structure, device and environment. According to specific needs, ordinary technicians in this field can adjust or modify these devices and environments. DETAILED DESCRIPTION

[0036] The following is a detailed description of an old pavement crack intelligent detection device and a method of use provided by the present invention in conjunction with the accompanying drawings and specific embodiments. At the same time, it is explained here that in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments, and those skilled in the art may also adopt other alternative methods to implement some known technologies; and the accompanying drawings are only for a more specific description of the embodiments, and are not intended to specifically limit the present invention.

[0037] It should be noted that the references to "one embodiment", "an embodiment", "an exemplary embodiment", "some embodiments" and the like in the specification indicate that the embodiments described may include specific features, structures or characteristics, but not every embodiment may include the specific features, structures or characteristics. In addition, when a specific feature, structure or characteristic is described in conjunction with an embodiment, it should be within the knowledge of a person skilled in the art to implement such feature, structure or characteristic in conjunction with other embodiments (whether or not explicitly described).

[0038] In general, a term can be understood, at least in part, from its use in context. For example, depending, at least in part, on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in the singular sense, or can be used to describe a combination of features, structures, or characteristics in the plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey an exclusive set of factors, but can instead, depending, at least in part, on the context, allow for the presence of other factors that are not necessarily explicitly described.

[0039] It will be understood that the meanings of “on,” “over,” and “above” in the present invention should be interpreted in the broadest manner, so that “on” not only means “directly on” something, but also includes the meaning of being “on” something with intervening features or layers therebetween, and “on” or “over” not only means “on” or “above” something, but also includes the meaning of being “on” or “above” something with no intervening features or layers therebetween.

[0040] Additionally, spatially relative terms such as "under," "beneath," "lower," "above," "upper," and the like may be used herein for descriptive convenience to describe the relationship of one element or feature to another element or features, as shown in the accompanying drawings. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the accompanying drawings. The device may be oriented in other ways, and the spatially relative descriptors used herein may be similarly interpreted accordingly.

[0041] like Figures 1 to 7As shown, an embodiment of the present invention provides an intelligent detection device for cracks in old pavement and a method for using the same, including a pavement moving component 1, a laser radar scanning component 2 is respectively passed through the edges on both sides of the center of the top surface of the pavement moving component 1, ultrasonic crack detection components 3 are respectively provided on both sides of the top surface of the pavement moving component 1 near the front end edge, a handle component 4 is provided at the rear end edge of the top surface of the pavement moving component 1, and the top surface of the pavement moving component 1 is covered with a shell component 5. There are two laser radar scanning components 2, and there are two ultrasonic crack detection components 3. One of the ultrasonic crack detection components 3 is an ultrasonic transmitter, and the other ultrasonic crack detection component 3 is an ultrasonic receiver. The use principle of the laser radar scanning component 2 is to use a laser as a transmitting light source and an active remote sensing device using photoelectric detection technology. Laser radar is an advanced detection method that combines laser technology with modern photoelectric detection technology. It is composed of a transmitting system, a receiving system, an information processing system, etc. The transmitting system is various The laser radar is composed of various forms of lasers, such as carbon dioxide lasers, neodymium-doped yttrium aluminum garnet lasers, semiconductor lasers and wavelength tunable solid lasers and optical beam expansion units; the receiving system adopts a telescope and various forms of photoelectric detectors, such as photomultiplier tubes, semiconductor photodiodes, avalanche photodiodes, infrared and visible light multi-element detection devices, etc. The laser radar adopts two working modes: pulse or continuous wave. The detection method can be divided into Mie scattering, Rayleigh scattering, Raman scattering, Brillouin scattering, fluorescence, Doppler and other laser radars according to the different detection principles. The laser scanning method is not only the main way for the military to obtain three-dimensional geographic information, but also the data obtained through this method has been widely used in resource exploration, urban planning, agricultural development, water conservancy projects, land use, environmental monitoring, transportation and communication, earthquake prevention and disaster reduction, and national key construction projects. It provides extremely important original data for national economic, social development and scientific research, and has achieved remarkable economic benefits, showing good application prospects. Compared with traditional measurement methods, the IDAR ground three-dimensional data acquisition method has the advantages of low field production cost and post-processing cost. Users are in urgent need of low-cost, high-density, fast and high-precision digital elevation data or digital surface data. Airborne L IDAR technology just meets this demand, so it has become a popular high-tech in various measurement applications.

[0042] The working principle of obtaining three-dimensional stereo images through lidar is as follows: the working principle of lidar is very similar to that of radar. It uses laser as the signal source. The pulsed laser emitted by the laser hits the trees, roads, bridges and buildings on the ground, causing scattering. Part of the light wave will be reflected to the lidar receiver. According to the laser ranging principle, the distance from the lidar to the target point is calculated. The pulsed laser continuously scans the target object, and the data of all target points on the target object can be obtained. After imaging processing with this data, an accurate three-dimensional stereo image can be obtained.

[0043] The principle of using ultrasonic wave to detect cracks is to first assume that the crack is an isosceles triangle. When the ultrasonic wave emitted by the transmitter propagates in the medium, there are both longitudinal waves and transverse waves. The speed of the longitudinal wave is greater than that of the transverse wave. The positions of the transmitter and the receiver are symmetrical. The angle of elastic wave transmission in the two media is determined by the wave speed. The route of ultrasonic wave propagation in the air is parallel to the horizontal direction. When the ultrasonic wave is emitted from the transmitter, the angle with the horizontal direction is set as θ, and the angle of the crack is set as 2θ. After this ultrasonic wave is transmitted into the air, the direction is parallel to the horizontal direction. The transmission law of one medium transmitting into another medium is obtained: V 气 is the speed of ultrasonic wave in dirty air, m / s, which can be solved as follows: V solid is in the range of 3000~5000m / s. Different solid media have different ultrasonic propagation speeds. Take an average value V 固 =4000m / s, the propagation speed of ultrasonic wave in gas V 气 is 340m / s. On this basis, the function graph of θ1 with respect to θ is given by The value range of θ is (0,4.876 0 ), it can be concluded that when the crack angle 2θ is greater than 9.752 0 When , there will be no θ1. The ultrasonic wave emitted by the transmitter cannot return to the receiver after entering the air between the cracks. Therefore, θ is a constant, so θ1 is uniquely determined. By taking different distances between the transmitter and the receiver, we can obtain different ultrasonic propagation paths. According to the ultrasonic path diagram, when L gradually increases to L%, the ultrasonic wave that enters the air and returns to the receiver has reached the maximum L. The propagation at this time is the same as the classical propagation path. Therefore, when actually measuring, the distance between the instruments should be set to When the ultrasonic wave is transmitted into the crack, it will return to the receiver, thus obtaining the depth of the crack.

[0044] like Figures 8 to 10As shown, the road moving component 1 includes a bottom plate 101, and an instrument mounting hole 102 is respectively opened at the center of the top surface of the bottom plate 101 near the left and right edges, and a radio remote control drive 103 is respectively provided at the edges of the front end and the rear end of the bottom surface of the bottom plate 101, and the left and right ends of each radio remote control drive 103 are respectively covered with a wheel shock absorber 104, and one end of each wheel shock absorber 104 is connected to a road wheel 105, and the handlebar component 4 includes a rotating drum mounting base 401, and the top surface of the rotating drum mounting base 401 is provided with a damping shaft 402, and the center of the top surface of the damping shaft 402 is provided with a mounting screw hole 403, and the mounting A threaded mounting rod 404 is provided inside the screw hole 403, a main fixing rod 405 is provided on the top of the threaded mounting rod 404, a rotating shaft 406 is provided on the top of the main fixing rod 405, an elliptical handle 407 passes through the rotating shaft 406, the outer shell assembly 5 includes an outer protective shell 501, a surrounding surveillance camera 502 is provided at the center of the top surface of the outer protective shell 501, a plurality of tool plug-in plates 503 are provided on the left and right side surfaces of the outer protective shell 501 in a matrix form, a front headlight 504 is provided at the center of the front end surface of the outer protective shell 501, and a crash barrier 505 is covered at the bottom edge at the center of the front end surface of the outer protective shell 501.

[0045] When used, an intelligent detection device for cracks in old pavement includes the following steps:

[0046] Step 1: First, place the whole device on the roadside. You can choose to use the remote control to remotely control the radio remote control driver 103 to control the moving direction of the road moving component 1, or you can choose to manually hold the handle component 4 to push or pull the road moving component 1 to adjust the moving direction;

[0047] Step 2: While the pavement moving component 1 is moving, the laser radar scanning component 2 and the ultrasonic crack detection component 3 can be started to scan the front and bottom ground to detect whether there are cracks on the pavement and the depth of the cracks. The ultrasonic crack detection component 3 is placed at the front end to first scan the ground to detect the crack depth and whether there are cracks. Then, the laser radar scanning component 2 at the rear is used to scan the ground and transmit the data to the background. Existing technology can be used to generate three-dimensional modeling diagrams in real time, which is convenient for subsequent staff to use.

[0048] The working principle of the technical solution provided by the present invention is as follows:

[0049] First, by setting up the wireless remote control drive 103 in the structure of the road moving component 1, the moving direction of the road moving component can be remotely controlled by a remote control. The road moving component can also be moved by manually holding the handle component to push or pull the road moving component to adjust the moving direction. In addition, the combination of laser radar scanning and ultrasonic detection of crack depth can better generate modeling diagrams in real time while detecting cracks, which is convenient for subsequent staff to use modeling diagrams and depth data in advance to adopt corresponding remedial measures when performing maintenance. Then, by setting up the surrounding monitoring camera 502 in the shell component 5 structure, the surrounding situation can be monitored, which is convenient for remote control personnel to watch the surrounding environment in real time, and the front headlights 504 can illuminate the road ahead when working at night. The role of the anti-collision guardrail 505 is to reduce the degree of impact in front if the remote control personnel cause a collision due to improper operation, and to protect the internal devices.

[0050] The present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention. In order to make the public have a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention, but those skilled in the art can fully understand the present invention without the description of these details. In addition, in order to avoid unnecessary confusion about the essence of the present invention, well-known methods, processes, procedures, components and circuits are not described in detail.

[0051] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. An intelligent detection device for cracks in old pavement, characterized in that: It comprises a pavement moving component, wherein laser radar scanning components are respectively penetrated at both side edges at the center of the top surface of the pavement moving component, ultrasonic crack detection components are respectively arranged at both sides of the front end edge of the top surface of the pavement moving component, a handle component is arranged at the rear end edge of the top surface of the pavement moving component, and the top surface of the pavement moving component is covered with a shell component; The number of the laser radar scanning components is two, the number of the ultrasonic crack detection components is two, one of the ultrasonic crack detection components is an ultrasonic transmitter, and the other of the ultrasonic crack detection components is an ultrasonic receiver.

2. The intelligent detection device for cracks in old pavement according to claim 1 is characterized in that: The road surface moving component includes a base plate, and instrument installation holes are respectively opened at the center of the top surface of the base plate near the left and right edges, and radio remote control drives are respectively provided at the edges of the front end and the rear end of the bottom surface of the base plate.

3. The intelligent detection device for cracks in old pavement according to claim 2 is characterized in that: The left and right ends of each of the radio remote-controlled drivable parts are respectively covered with wheel shock absorbers, and one end of each of the wheel shock absorbers is connected to a road wheel.

4. The intelligent detection device for cracks in old pavement according to claim 1 is characterized in that: The handle assembly comprises a rotating drum mounting base, a damping rotating shaft is arranged on the top surface of the rotating drum mounting base, and a mounting screw hole is arranged at the center of the top surface of the damping rotating shaft.

5. The intelligent detection device for cracks in old pavement according to claim 4 is characterized in that: A threaded mounting rod is arranged inside the mounting screw hole, a main fixing rod is arranged on the top of the threaded mounting rod, a rotating shaft is arranged on the top of the main fixing rod, and an elliptical handle runs through the inside of the rotating shaft.

6. The intelligent detection device for cracks in old pavement according to claim 1 is characterized in that: The housing assembly comprises an outer protective shell, a surrounding monitoring camera is arranged at the center of the top surface of the outer protective shell, and a plurality of tool plug-ins are arranged in a matrix form on the left and right side surfaces of the outer protective shell.

7. The intelligent detection device for cracks in old pavement according to claim 6 is characterized in that: A front headlight is arranged at the center of the front end surface of the outer protective shell, and a crash barrier is covered at the bottom edge of the center of the front end surface of the outer protective shell.

8. The method for using the intelligent detection device for cracks in old pavement according to claim 1 is characterized in that: The operating principle of the laser radar scanning component is to use a laser as a transmitting light source and an active remote sensing device using photoelectric detection technology. The laser radar is an advanced detection method that combines laser technology with modern photoelectric detection technology. It is composed of a transmitting system, a receiving system, an information processing system, and the like. The transmitting system is composed of various forms of lasers, such as a carbon dioxide laser, a neodymium-doped yttrium aluminum garnet laser, a semiconductor laser, a wavelength-tunable solid laser, and an optical beam expansion unit; the receiving system uses a telescope and various forms of photoelectric detectors, such as a photomultiplier tube, a semiconductor photodiode, an avalanche photodiode, an infrared and visible light multi-element detection device, and the like. The laser radar uses a pulse or continuous wave working mode, and the detection method can be divided into Mie scattering, Rayleigh scattering, Raman scattering, Brillouin scattering, fluorescence, Doppler and other laser radars according to different detection principles.

9. The method for using the intelligent detection device for cracks on old pavement according to claim 1, characterized in that: The principle of using ultrasonic wave to detect cracks is to first assume that the crack is an isosceles triangle. When the ultrasonic wave emitted by the transmitter propagates in the medium, there are both longitudinal waves and transverse waves. The speed of the longitudinal wave is greater than that of the transverse wave. The positions of the transmitter and the receiver are symmetrical. The angle of transmission of the elastic wave in the two media is determined by the wave speed. The route of ultrasonic wave propagation in the air is parallel to the horizontal direction. When the ultrasonic wave is emitted from the transmitter, the angle with the horizontal direction is θ, and the angle of the crack is 2θ. After this ultrasonic wave is transmitted into the air, the direction is parallel to the horizontal direction. The transmission law of one medium transmitting into another medium is obtained: V 气 is the speed of ultrasonic wave in dirty air, m / s, which can be solved as follows: V solid is in the range of 3000~5000m / s. Different solid media have different ultrasonic propagation speeds. Take an average value V 固 =4000m / s, the propagation speed of ultrasonic wave in gas V 气 is 340m / s. On this basis, the function graph of θ1 with respect to θ is given by The value range of θ is (0,4.876 0 ), it can be concluded that when the crack angle 2θ is greater than 9.752 0 When , there will be no θ1. The ultrasonic wave emitted by the transmitter cannot return to the receiver after entering the air between the cracks. Therefore, θ is a constant, so θ1 is uniquely determined. By taking different distances between the transmitter and the receiver, we can obtain different ultrasonic propagation paths. According to the ultrasonic path diagram, when L gradually increases to L%, the ultrasonic wave that enters the air and returns to the receiver has reached the maximum L. The propagation at this time is the same as the classical propagation path. Therefore, when actually measuring, the distance between the instruments should be set to When the ultrasonic wave is transmitted into the crack, it will return to the receiver, thus obtaining the depth of the crack.

10. The method for using the intelligent detection device for cracks on old pavement according to claims 1-9 is characterized in that: The following steps are involved: Step 1: First, place the whole device on the roadside. You can choose to use the remote control to remotely control the moving direction of the road moving component, or you can choose to manually hold the handle component to push or pull the road moving component to adjust the moving direction; Step 2: While the pavement moving component is moving, the laser radar scanning component and the ultrasonic crack detection component can be started to scan the front and bottom ground to detect whether there are cracks on the pavement and the depth of the cracks. The ultrasonic crack detection component is placed at the front end to first scan the ground to detect the crack depth and whether there are cracks. Then, the laser radar scanning component at the rear is used to scan the ground and transmit the data to the background. Existing technology can be used to generate three-dimensional modeling diagrams in real time, which is convenient for subsequent staff to use.

Images