A machine vision-based multi-pipe defect detection trolley

Abstract

The application provides a kind of multiple pipeline defect detection trolley based on machine vision, including detection structure, multiple mobile structures, spherical connectors, power structure and control device, multiple mobile structures are all arranged in the inner wall of pipeline, and are all in contact with the inner wall of pipeline, mobile structures are connected by spherical connectors, the front end of mobile structure located in the front end of advancing direction is connected with detection structure, so that detection structure detects the defects of inner wall of pipeline, the rear end of mobile structure located in the rear end of advancing direction is connected with power structure, so that power structure drives mobile structure to move along the inner wall of pipeline, control device is signal connected with power structure and detection structure, so that control device controls power structure to operate, solve the problem that when observing the defects in the pipeline in the prior art, the internal environment is not suitable for observation, and when checking by artificial through camera, it will be missed, and it will cause problems in artificial detection, leading to the difficulty of later maintenance.

Description

Technical Field

[0001] This invention belongs to the field of pipeline inspection technology, specifically relating to a multi-pipeline defect detection vehicle based on machine vision. Background Technology

[0002] Gas pipelines are a vital urban infrastructure, playing a crucial role in ensuring people's daily lives. Over time, pipelines develop various defects, necessitating regular inspections. However, some gas pipelines are not easily inspected manually.

[0003] In existing technologies, when observing defects inside pipelines, the internal environment of gas pipelines is not suitable for observation, and omissions may occur during manual inspection. Gas pipelines have more than one type of defect, such as cracks. Multiple defects can cause problems in manual inspection, leading to difficulties in later maintenance. Furthermore, the inspection device is not easy to turn and is prone to dead angles, making it unsuitable for pipelines of all diameters. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to provide a multi-pipe defect detection cart based on machine vision, which can solve the problems in the prior art when observing defects inside the pipe, such as the internal environment being difficult to observe, omissions during manual inspection, problems in manual inspection leading to difficulties in later maintenance, and the detection device being difficult to turn, prone to blind spots, and not applicable to pipes of all diameters.

[0005] To address the aforementioned issues, this invention provides a multi-pipe defect detection vehicle based on machine vision, comprising a detection structure, multiple moving structures, a spherical connector, a power structure, and a control device.

[0006] Multiple moving structures are installed on the inner wall of the pipe and are in contact with the inner wall of the pipe. The moving structures are connected to each other by ball connectors. The front end of the moving structure located at the front end in the forward direction is connected to the detection structure so that the detection structure can detect defects in the inner wall of the pipe. The rear end of the moving structure located at the rear end in the forward direction is connected to the power structure so that the power structure can drive the moving structure to move along the inner wall of the pipe. The control device is connected to both the power structure and the detection structure by signal so that the control device can control the operation of the power structure.

[0007] Optionally, the moving structure includes a herringbone bracket, a variable diameter structure, and guide wheels;

[0008] The outer surface of the herringbone bracket has three variable diameter structures evenly arranged along the circumferential direction. Each variable diameter structure is connected to a guide wheel. The middle of the herringbone brackets is connected by a spherical connector. The front end of the herringbone bracket located at the front of the forward direction is equipped with a detection structure, and the rear end of the herringbone bracket located at the rear of the forward direction is equipped with a power structure.

[0009] Optionally, the variable diameter structure includes an inner cylinder, multiple slide rails, an outer cylinder, and an adjusting spring;

[0010] The closed end of the outer cylinder is connected to the guide wheel. The adjusting spring is movably embedded in the inner cavity of the outer cylinder. Multiple slide rails are evenly arranged on the inner sidewall of the outer cylinder along the circumferential direction. The inner cylinder is movably embedded in the inner cavity of the outer cylinder and is slidably connected to the slide rails. One end of the inner cylinder located in the inner cavity of the outer cylinder is connected to one end of the adjusting spring, and the other end of the inner cylinder located on the outer side of the outer cylinder is connected to the herringbone bracket.

[0011] Optionally, the detection structure includes a first connecting flange, a fastener, and a monocular camera;

[0012] The first connecting flange is connected to the front wall of the herringbone bracket located at the front end in the forward direction, and the monocular camera is set at the center of the side wall of the first connecting flange.

[0013] Optionally, the center of the monocular camera and the center of the pipe are coaxial.

[0014] Optionally, the power structure includes an adjustment mechanism, a motor, and multiple drive wheels;

[0015] The adjustment structure is connected to the rear side wall of the herringbone bracket located at the rear end in the forward direction. The motor is mounted on the adjustment structure, and multiple transmission wheels are evenly and dynamically connected to both sides of the adjustment structure. The motor is also connected to the multiple transmission wheels.

[0016] Optionally, the adjustment structure includes a second connecting flange, a fixed shaft, a motor support, and a support spring;

[0017] One side wall of the second connecting flange is connected to the rear side wall of the herringbone bracket located at the rear end in the forward direction. The other side wall of the second connecting flange is provided with an inner groove. One end of the motor support is embedded in the inner groove, and a first through hole is provided on the motor support embedded in the inner groove. A second through hole is provided on the upper end face of the second connecting flange, and the second through hole is connected to the inner groove. One end of the fixed shaft passes through the second through hole, the inner groove and the first through hole in sequence, and the lower end of the fixed shaft is fixedly connected to the inside of the second connecting flange. The support spring is sleeved on the outer surface of the fixed shaft. One end of the support spring contacts the upper surface of the inner groove, and the other end of the support spring contacts the upper surface of the motor support.

[0018] The motor support has a mounting slot, in which the motor is installed. Multiple transmission wheels are evenly distributed on both sides of the motor support, and the output end of the motor is connected to the multiple transmission wheels.

[0019] Beneficial effects

[0020] The embodiments of this invention provide a machine vision-based pipeline defect detection cart. A power structure drives a transmission wheel, thereby enabling the movement of the moving structure. The position of the transmission wheel can be changed by adjusting the structure, and the position of the guide wheel can be changed by a variable-diameter structure. This allows the cart to be used with pipes of different inner diameters during inspection, while ensuring that the center of the monocular camera is always coaxial with the center of the pipe. This not only facilitates inspection but also improves inspection accuracy and precision. The cart travels through the pipe, transmitting images back to the display and control terminal. The display and control terminal processes the images returned by the cart using a machine vision-based method, marking the locations of defects. This machine vision-based processing and defect marking of the images returned by the inspection cart can replace manual screening of pipeline defects. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the three-dimensional structure of the detection cart according to an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of the herringbone bracket according to an embodiment of the present invention;

[0023] Figure 3 This is a schematic diagram of the detection structure according to an embodiment of the present invention;

[0024] Figure 4 This is a schematic diagram of the detection experiment according to an embodiment of the present invention;

[0025] Figure 5 This is a schematic diagram of the adjustment structure according to an embodiment of the present invention;

[0026] Figure 6 This is a schematic diagram of the variable diameter structure according to an embodiment of the present invention.

[0027] The reference numerals in the attached figures are as follows:

[0028] 1. First connecting flange; 2. Fastener; 3. A-frame bracket; 4. Guide wheel; 5. Spherical connector; 6. Second connecting flange; 7. Fixed shaft; 8. Motor support; 9. Motor; 10. Transmission wheel; 11. Monocular camera; 12. Support spring; 13. Inner cylinder; 14. Slide rail; 15. Outer cylinder; 16. Adjusting spring. Detailed Implementation

[0029] See also Figures 1 to 6 As shown in the figure, according to an embodiment of the present invention, a multi-pipe defect detection vehicle based on machine vision is described. Please refer to... Figure 1The invention includes a detection structure, multiple moving structures, a spherical connector 5, a power structure, and a control device. The multiple moving structures are all disposed on and in contact with the inner wall of the pipe. The moving structures are connected to each other via the spherical connector 5. The front end of the moving structure located at the forward direction is connected to the detection structure, enabling the detection structure to detect defects on the inner wall of the pipe. The rear end of the moving structure located at the rear direction is connected to the power structure, enabling the power structure to drive the moving structures along the inner wall of the pipe. The control device is signal-connected to the power structure, enabling the control device to control the operation of the power structure. This invention controls the movement of the power structure through the control device, driving the moving structures to move along the inner wall of the pipe. Multiple moving structures are interconnected via the spherical connector 5, and the detection structure feeds back the detected results to the control device. This facilitates detection and observation, avoiding omissions during manual inspection. It solves the problems in existing technologies where observing defects inside pipes is difficult due to the unfavorable internal environment, and omissions can occur during manual inspection using cameras, leading to problems in manual inspection and difficulties in later maintenance.

[0030] Furthermore, the detection structure is used to detect various defects on the inner wall of the pipe and feeds back the detected defects to the control device. The control device can obtain various defects in the pipe and the number of defects, which is convenient and error-free.

[0031] Furthermore, the number of movable structures is multiple, and the specific number can be selected according to actual use. The movable structures are interconnected by spherical connectors 5, which are also connected to the middle of the movable structures. This allows the movable structures to smoothly pass through bends in the inner wall of the pipe, improving the overall strength and stability of the movable structures. It also increases the overall flexibility of the trolley.

[0032] Furthermore, the spherical connector 5 has a wide rotation range with no dead angles, which can prevent the trolley from jamming due to a single rotation direction or damage to the trolley due to excessive rotation speed when the trolley is turning.

[0033] Furthermore, the power structure provides the overall trolley with the power to move forward, and the control device controls the power structure to provide the overall trolley with the power to move. The power structure can also be adjusted according to the diameter of the inner wall of the pipe to make the movement of the overall trolley more stable, while ensuring that the center of the detection structure and the center of the pipe are on the same center, thereby improving the detection accuracy and precision of the detection structure.

[0034] Furthermore, the structure enables the entire vehicle to move unimpeded along the entire pipeline network by relying on the motor 9 of the power structure, capturing images of the inner surface of the tested pipeline without blind spots. Moreover, the structure is relatively simple, the component connections are simple and stable, and the overall operation in the pipeline is relatively stable.

[0035] Please refer to Figure 2 The moving structure includes a herringbone bracket 3, a variable diameter structure, and guide wheels 4. Three variable diameter structures are evenly arranged circumferentially on the outer surface of the herringbone bracket 3, each connected to a guide wheel 4. The middle sections of the herringbone brackets 3 are connected by spherical connectors 5. A detection structure is installed at the front end of the herringbone bracket 3 in the forward direction, and a power structure is installed at the rear end of the herringbone bracket 3 in the forward direction. The guide wheels 4 move along the inner wall of the pipe, driving the herringbone bracket 3 to move as a whole. The variable diameter structure adjusts the distance between the guide wheels 4 and the herringbone brackets 3 according to the inner diameter of the pipe. This ensures that the moving structure can be used for pipes with different inner diameters, enabling defect detection on the inner walls of pipes with varying inner diameters.

[0036] Furthermore, protruding blocks are evenly distributed on the circumferential outer surface of the herringbone bracket 3, and left and right spherical connecting grooves are provided at the center of the herringbone bracket 3. The spherical connector 5 is movably embedded in the spherical connecting groove, so that the spherical connector 5 can rotate at multiple angles in the spherical connecting groove, thereby ensuring that the herringbone bracket 3 can turn on the inner wall of the pipe.

[0037] Furthermore, the guide wheel 4 is a passive, unpowered wheel. Power is supplied to the transmission wheel 10 through a power structure, meaning that when the transmission wheel 10 moves, the guide wheel 4 moves.

[0038] Please refer to Figure 6 The variable diameter structure includes an inner cylinder 13, multiple slide rails 14, an outer cylinder 15, and an adjusting spring 16. The closed end of the outer cylinder 15 is connected to a guide wheel 4. The adjusting spring 16 is movably embedded in the inner cavity of the outer cylinder 15. The multiple slide rails 14 are evenly arranged on the inner sidewall of the outer cylinder 15 along its circumferential direction. The inner cylinder 13 is movably embedded in the inner cavity of the outer cylinder 15 and is slidably connected to the slide rails 14. One end of the inner cylinder 13 located in the inner cavity of the outer cylinder 15 is connected to one end of the adjusting spring 16, and the other end of the inner cylinder 13 located on the outer side of the outer cylinder 15 is connected to a herringbone bracket 3. Under the action of the adjusting spring 16, the inner cylinder 13 can slide along the inner cavity of the outer cylinder 15, thus enabling the inspection of pipes with different diameters.

[0039] Furthermore, the guide wheel 4 is provided with four threaded holes. By screwing in the screws, the closed end of the outer cylinder 15 is fixedly connected to the guide wheel 4. The other end of the outer cylinder 15 is movably embedded with the adjusting spring 16 and the inner cylinder 13. One end of the adjusting spring 16 is fixedly connected to the inner cavity of the outer cylinder 15, and the other end of the adjusting spring 16 is fixedly connected to one end of the inner cylinder 13.

[0040] Furthermore, multiple slide rails 14 are threadedly fixed to the inner wall of the outer cylinder 15, and the outer surface of the inner cylinder 13 is slidably connected to the slide rails 14, thus guiding the inner cylinder 13 to move linearly along the outer cylinder 15. The outer diameter of the inner cylinder 13 is slightly smaller than the inner diameter of the outer cylinder 15, which not only ensures that the inner cylinder 13 can move along the inner cavity of the outer cylinder 15, but also makes the movement stable and smooth.

[0041] Furthermore, when the pipe radius is greater than the herringbone support 3, the adjusting spring 16 extends, and the inner cylinder 13 slides outward, increasing the distance between the inner cylinder 13 and the outer cylinder 15 until the guide wheel 4 contacts the pipe wall. When the pipe radius is smaller than the herringbone support 3, the adjusting spring 16 is compressed by the pipe wall, causing the inner cylinder 13 to slide inward, shortening the distance between the inner cylinder 13 and the outer cylinder 15 until it conforms to the pipe wall. The slide rail design ensures that excessive friction between the inner cylinder 13 and the outer cylinder 15 is reduced, thus minimizing the difficulty or inability to change the diameter.

[0042] Please refer to Figure 3 The detection structure includes a first connecting flange 1, a fastener 2, and a monocular camera 11. The first connecting flange 1 is connected to the front wall of a herringbone bracket 3 located at the front end in the forward direction, and the monocular camera 11 is positioned at the center of the side wall of the first connecting flange 1. The monocular camera 11, mounted on the first connecting flange 1, is used to detect defects on the inner wall of the pipe.

[0043] Furthermore, the first connecting flange 1 is a multi-functional flange, and a mounting hole is provided at the center of the first connecting flange 1. The monocular camera 11 is installed inside the mounting hole, and the center line of the monocular camera 11 is on the same straight line as the center line of the pipeline, that is, it is always located in the same axial position, which improves the accuracy of detection.

[0044] Furthermore, the monocular camera 11 is a fisheye monocular camera, and the focal point of the monocular camera 11 is parallel to the axis of the pipe.

[0045] Furthermore, the first connecting flange 1 has three threaded holes, and the monocular camera 11 can be fixed to the first connecting flange 1 using fixing screws. The first connecting flange 1 has three additional threaded holes on the outer side, which can be used to fix monocular cameras of different specifications. Since the center of the mounting hole of the monocular camera 11 in the middle of the first connecting flange 1 is always coaxial with the pipe being measured, this design can ensure that the focus of the monocular camera 11 is coaxial with the pipe axis and that the acquired image is free from offset and distortion.

[0046] Furthermore, the first connecting flange 1 is fixedly connected to the front end of the first herringbone bracket 3 located in the forward direction. The fastener 2 is a portal-type fastener, which fixes the first flange to the herringbone bracket 3 through the protruding groove on the first connecting flange 1.

[0047] The power structure includes an adjustment structure, a motor 9, and multiple drive wheels 10. The adjustment structure is connected to the rear side wall of the herringbone bracket 3 located at the rear end in the forward direction. The motor 9 is mounted on the adjustment structure, and the multiple drive wheels 10 are evenly and movably connected to both sides of the adjustment structure, with the motor 9 connected to the multiple drive wheels 10. The motor 9 provides power to the drive wheels 10, driving the entire moving structure to move along the inner side wall of the pipe. By adjusting the position of the motor 9 through the adjustment structure, the position of the drive wheels 10 is adjusted, making it suitable for detecting pipes with different inner diameters.

[0048] For further details, please refer to Figure 5 The adjustment structure includes a second connecting flange 6, a fixed shaft 7, a motor support 8, and a support spring 12. One side wall of the second connecting flange 6 is connected to the rear side wall of the herringbone bracket 3 located at the rear end in the forward direction. The other side wall of the second connecting flange 6 is provided with an inner groove. One end of the motor support 8 is embedded in the inner groove, and a first through hole is provided on the motor support 8 embedded in the inner groove. A second through hole is provided on the upper end face of the second connecting flange 6, and the second through hole is connected to the inner groove. One end of the fixed shaft 7 passes through the second through hole, the inner groove, and the first through hole in sequence, and the lower end of the fixed shaft 7 is fixedly connected to the interior of the second connecting flange 6. The support spring 12 is sleeved on the outer surface of the fixed shaft 7. One end of the support spring 12 contacts the upper surface of the inner groove, and the other end of the support spring 12 contacts the upper surface of the motor support 8. The motor support 8 is provided with a mounting groove, and the motor 9 is installed in the mounting groove. Multiple transmission wheels 10 are evenly arranged on both sides of the motor support 8, and the output end of the motor 9 is connected to multiple transmission wheels 10.

[0049] Furthermore, the motor 9 is installed in the motor support 8, and finally the motor 9 is directly fixed to the mounting groove in the motor support 8 by threads. The other side wall of the second connecting flange 6 is provided with an inner groove. The front end of the motor support 8 is placed into the inner groove for fitting. The fixing shaft 7 is inserted into the first through hole of the motor support 8 from the second through hole at the upper part of the second connecting flange 6, and is fixedly connected to the lower end of the second connecting flange 6 by threads. A support spring 12 is provided at the inner groove. The support spring 12 is sleeved on the outer surface of the fixing shaft 7 and its purpose is to adjust the position of the motor support 8.

[0050] Furthermore, when the fixed shaft 7 is installed, the motor support 8 is inserted into the support spring 12 to form a spring-damped sliding pair, so that the motor support 8 and the second connecting flange 6 are in a relative movable relationship, and the motor support 8 can move up and down along the fixed shaft 7 within the inner groove of the second connecting flange 6.

[0051] Furthermore, when the pipe radius is large, the support spring 12 extends, causing the motor support 8 to move downwards and contact the pipe wall; when the pipe radius is small, the support spring 12 shortens, causing the motor support 8 to move upwards. This ensures that the motor support 8 can change with the A-frame bracket 3 as the pipe radius changes, keeping the monocular camera 11 axially aligned. This prevents the trolley from tilting upwards or downwards only when the A-frame bracket 3 changes, and also gives the drive wheel 10 installed therethe the ability to change diameter.

[0052] Furthermore, the motor 9 is connected to the transmission wheel 10 via a coupling, and the transmission wheel 10 is connected to the transmission shaft. As shown in the figure, a corresponding transmission shaft hole is opened at the rear end of the motor support 8, through which the transmission shaft connected to the motor 9 passes, and the transmission shaft is then connected to the transmission wheel 10.

[0053] Furthermore, related circuitry is installed on the motor support component 8. This circuitry consists of two modules: a communication module and a drive module. The communication module is connected to the drive module, and control signals are received from the communication module and sent to the drive module via serial port transmission to ultimately control the actions of the image acquisition vehicle. The Arduino Nano V3.0 development board selected in this paper uses the Atmega328P-AU control chip, which includes 12 digital input / output ports and 8 analog input / output ports. The program and communication protocol can be modified arbitrarily to connect the motor power supply to the circuit interface. This completes the assembly of the pipeline vehicle.

[0054] The control device includes a control terminal and a display terminal. The control terminal and display terminal control the forward and backward movement of the vehicle. When the remote sensor sends a signal, it acts on... Figure 1 The control circuit is installed on the motor support 8. The control circuit controls the forward and backward movement of the motor 9. The motor 9 drives the entire trolley to move by acting on the transmission wheel 10. The image transmitted by the monocular camera 11 is displayed on the display end, and the relevant parameters mentioned are also displayed in the corresponding positions.

[0055] Before placing the inspection trolley, make the necessary preparations, turn on the switch on the circuit of the motor support 8, turn on the monocular camera 11 on the front A-frame bracket 3 of the inspection trolley, and use both hands to send the inspection trolley to the pipe opening. Adjust the guide wheels 4 on the A-frame bracket 3 to allow the inspection trolley to enter the pipe. Since the monocular camera 11 is installed on the first connecting flange 1, the field of view of the monocular camera 11 is stabilized. Turn on the display and control system to complete the connection with the wireless trolley. The display end and the control end display two images, one of which shows the detection of defects, and the preparation work is completed.

[0056] In one implementation method, the operation of the detection trolley is monitored. When the straight pipe is running, the herringbone support 3 reaches a stable state. The display and control end is pushed forward, and the motor 9 drives the transmission wheel 10 to move. The detection trolley moves forward, and the number and type of defects detected are collected and recorded. After the detection is completed, the remote control of the display and control end is pushed backward, and the motor 9 drives the transmission wheel 10 to move backward. The trolley begins to exit, and the detection is completed.

[0057] In one implementation method, the operation of the detection trolley is monitored. When the trolley is running through a pipe that requires a turn, the display control terminal is pushed forward. The motor 9 drives the transmission wheel 10 to move, and the detection trolley moves forward. The herringbone bracket 3 changes angle accordingly in the curved pipe, allowing it to pass through the curved gas pipe. The spherical connector 5 is achieved through the cooperation of a spherical rod and a spherical connecting groove. During forward movement, the herringbone bracket 3 receives pressure from the curved pipe, causing the spherical rod to rotate within the spherical connecting groove, resulting in an angle change of 60-80 degrees, enabling the trolley to complete the turning function. The same detection is performed during forward movement. After the detection is completed, the remote control on the display terminal and control terminal is pushed backward. The motor 9 drives the transmission wheel 10 to move backward, and the trolley begins to exit, completing the detection.

[0058] The circuit on the trolley motor support 8 has the following functions:

[0059] 1. Control the forward and backward movement of the trolley and the lights on the monocular camera 11;

[0060] 2. The circuit has a transmission function, interconnecting with the display and control terminals;

[0061] Combination Figure 4 As shown, the display and control terminals demonstrate the detection effect of gas pipeline defects, capable of detecting different pipeline defects and marking the number of defects.

[0062] like Figure 4As shown, the interface of the display and control terminal can standardize the defects in the pipeline and display the number of detected defects in the table on the right. The image after machine vision processing is displayed on the right, and the image transmitted by the original camera is on the left. By comparing the left and right images, it can be seen that the image after machine vision processing will mark the defects with curves and display the number of corresponding types of defects on the far right. The upper part is the control terminal that connects the display and control terminal to the detection trolley and is responsible for the connection with the trolley. The lower part shows the number of corresponding defect types and some basic operations of the display and control terminal.

[0063] This invention, through kinematic software analysis and multiple practical tests, achieves stable vehicle movement, reduces the probability of sideslip, and ensures smooth operation of the inspection vehicle in the gas pipeline, guaranteeing that the images captured by the monocular camera 11 are free from offset and distortion. The defect display is integrated with the control unit in the control device for real-time pipeline defect detection. Remote sensing is installed in both the display and control units to control the inspection vehicle. The detection and control units are combined, and the display system screen is divided into two parts: the left part displays the real-time image transmitted from the monocular camera 11, and the right part displays the annotated image after machine vision processing. The system is configured to record the corresponding number of defects annotated in the upper right corner of both the display and control screens. This approach allows the inspection vehicle to provide a comparative effect during inspection, accurately identifying the type of defect and its location, facilitating subsequent defect handling and repair.

[0064] This invention designs a detection cart and a display and control terminal. The cart travels through a pipeline and transmits images back to the display and control terminal. The display and control terminal processes the images transmitted by the cart using a machine vision-based method, marking the locations of defects. In the design of the cart, a variable-diameter structure is designed to adapt to different pipeline sizes. The radius of the herringbone support 3 is changed to accommodate different sizes. In order to match the variable diameter of the herringbone support 3, the diameter of the rear drive wheel 10 is changed through the change of the motor support 8, so that the cart as a whole can adapt to pipelines with different radii and complete the task of transmitting images of the inside of the pipeline back to the display and control terminal.

[0065] It will be readily understood by those skilled in the art that the aforementioned advantageous methods can be freely combined and superimposed without conflict.

Claims

1. A machine vision-based multi-pipeline defect detection vehicle, characterized in that, Includes a detection structure, multiple moving structures, a spherical connector (5), a power structure, and a control device; Multiple moving structures are installed on the inner wall of the pipe and are in contact with the inner wall of the pipe. The moving structures are connected to each other by ball connectors (5). The front end of the moving structure located at the front end of the forward direction is connected to the detection structure so that the detection structure can detect defects in the inner wall of the pipe. The rear end of the moving structure located at the rear end of the forward direction is connected to the power structure so that the power structure can drive the moving structure to move along the inner wall of the pipe. The control device is connected to both the power structure and the detection structure so that the control device can control the operation of the power structure. The movable structure includes a herringbone bracket (3), a variable diameter structure, and guide wheels (4); The outer surface of the herringbone bracket (3) is uniformly provided with three variable diameter structures along the circumferential direction. Each variable diameter structure is connected to a guide wheel (4). The middle parts of the herringbone brackets (3) are connected by a ball connector (5). The front end of the herringbone bracket (3) located at the front end of the forward direction is equipped with a detection structure, and the rear end of the herringbone bracket (3) located at the rear end of the forward direction is equipped with a power structure. The detection structure includes a first connecting flange (1), a fastener (2), and a monocular camera (11); The first connecting flange (1) is connected to the front wall of the herringbone bracket (3) located at the front end in the forward direction by a fastener (2), and the monocular camera (11) is set at the center of the side wall of the first connecting flange (1); The center of the monocular camera (11) is coaxial with the center of the pipe; The power structure includes an adjustment structure, a motor (9) and multiple transmission wheels (10); The adjustment structure is connected to the rear side wall of the herringbone bracket (3) located at the rear end in the forward direction. The motor (9) is mounted on the adjustment structure. Multiple transmission wheels (10) are evenly and dynamically connected to both sides of the adjustment structure, and the motor (9) is connected to the multiple transmission wheels (10). The adjustment structure includes a second connecting flange (6), a fixed shaft (7), a motor support (8), and a support spring (12). One side wall of the second connecting flange (6) is connected to the rear side wall of the herringbone bracket (3) located at the rear end in the forward direction. The other side wall of the second connecting flange (6) is provided with an inner groove. One end of the motor support (8) is embedded in the inner groove, and a first through hole is provided on the motor support (8) embedded in the inner groove. A second through hole is provided on the upper end face of the second connecting flange (6), and the second through hole is connected to the inner groove. One end of the fixed shaft (7) passes through the second through hole, the inner groove and the first through hole in sequence, and the lower end of the fixed shaft (7) is fixedly connected to the interior of the second connecting flange (6). The support spring (12) is sleeved on the outer surface of the fixed shaft (7). One end of the support spring (12) contacts the upper surface of the inner groove, and the other end of the support spring (12) contacts the upper surface of the motor support (8).

2. The machine vision based multi-pipeline defect detection trolley as claimed in claim 1 wherein, The variable diameter structure includes an inner cylinder (13), multiple slide rails (14), an outer cylinder (15), and an adjusting spring (16). The closed end of the outer cylinder (15) is connected to the guide wheel (4), the adjusting spring (16) is movably embedded in the inner cavity of the outer cylinder (15), multiple slide rails (14) are evenly arranged on the inner side wall of the outer cylinder (15) along the circumferential direction of the inner side wall of the outer cylinder (15), the inner cylinder (13) is movably embedded in the inner cavity of the outer cylinder (15), and the inner cylinder (13) is slidably connected to the slide rail (14). One end of the inner cylinder (13) located in the inner cavity of the outer cylinder (15) is connected to one end of the adjusting spring (16), and one end of the inner cylinder (13) located on the outer side of the outer cylinder (15) is connected to the herringbone bracket (3).

3. The machine vision based multi-pipeline defect detection trolley as claimed in claim 1 wherein, The motor support (8) is provided with a mounting groove, the motor (9) is installed in the mounting groove, and multiple transmission wheels (10) are evenly arranged on both sides of the motor support (8). The output end of the motor (9) is connected to multiple transmission wheels (10).

Images