Method and device for detecting culverts

Abstract

The application discloses a kind of detection method and device of culvert, belong to pipeline detection equipment technical field.The device includes a central main body case, multiple wheel arm assemblies arranged in the outer periphery of central main body case, screw drive mechanism arranged in the inside of central main body case and the synchronous connecting rod mechanism connected between screw drive mechanism and wheel arm assembly.Screw drive mechanism includes the central drive screw arranged along the central axis of central main body case and the driven slider moving along the axis.Synchronous connecting rod mechanism is used to convert the axial linear motion of driven slider into the swing of multiple wheel arm assemblies around its pivot end efficiently and synchronously, the application realizes the quick adaptation and stable support of different pipe diameter culvert by single driving source and precise mechanical linkage structure, the core transmission component is built-in in sealed machine case, improves the working reliability and service life of device in harsh environment, overall structure is compact, transmission efficiency is high.

Description

Technical Field

[0001] This invention relates to the field of pipeline inspection equipment technology, and in particular to a culvert inspection device for inspecting the internal structure of underground pipelines, tunnels and culverts. Background Technology

[0002] As important drainage facilities under highway and railway subgrades, the structural health of culverts directly affects the stability of the subgrade and traffic safety. Because culverts are typically buried at great depths, have varying pipe diameters, and suffer from harsh internal environments (such as water accumulation, silt, and harmful gases), traditional manual inspection methods pose significant safety risks, are inefficient, and are highly susceptible to subjective influences, making comprehensive and objective assessments difficult.

[0003] To address these issues, various pipeline inspection robots have emerged on the market. However, existing pipeline inspection robots still have many shortcomings when dealing with complex and ever-changing culvert environments.

[0004] One major pain point is its poor environmental adaptability. Many pipeline inspection robots employ a fixed wheelbase or track width design, limiting their applicability to pipe diameters with only specific or limited variations. When encountering culverts with pipe diameters much larger than the robot's wheelbase, the robot has few contact points with the pipe wall, resulting in unstable support and a tendency to skid and overturn, causing the drive wheels to slip and become suspended in the air, hindering effective movement. Conversely, the robot cannot enter culverts with excessively small pipe diameters. To inspect culverts of varying diameters, users often need to purchase multiple units of different specifications, significantly increasing procurement costs and the complexity of equipment management.

[0005] The second pain point lies in the complexity and reliability of the adjustment mechanisms. To address pipe diameter adaptability, some robots have designed adjustable support arms or wheel arms. However, these adjustment mechanisms are often quite complex. For example, some devices use pneumatic or hydraulic cylinders to drive the extension of the arms, requiring additional air sources or hydraulic pumps. This results in complex system piping, a susceptibility to leaks, and difficulty in guaranteeing reliability in harsh outdoor environments. Other devices equip each wheel arm with an independent drive motor, using a control system to coordinate the movements of multiple motors for synchronous extension and retraction. This approach not only has complex control logic and extremely high requirements for the synchronization performance of each motor, but also means that if any motor loses synchronization or malfunctions, the entire mechanism may jam or be damaged. Furthermore, the configuration of multiple motors increases the energy consumption and potential points of failure. These complex adjustment mechanisms make equipment maintenance difficult and also drive up manufacturing costs.

[0006] Therefore, how to design a detection device that is simple and reliable in structure, can quickly adapt to different pipe diameters, and can work stably in the harsh environment of culverts is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0007] In order to solve the technical problems mentioned in the background art, such as poor environmental adaptability, unstable support, complex adjustment mechanism and low reliability of existing culvert detection devices, the present invention proposes a culvert detection method and device to more accurately solve the problems mentioned in the background art.

[0008] This invention is achieved through the following technical solution: This invention proposes a method and apparatus for detecting culverts, including a central main housing and a wheel arm assembly disposed on the outer periphery of the central main housing, and further including: a screw drive mechanism disposed inside the central main housing; the screw drive mechanism includes a central drive screw arranged along the central axis of the central main housing, and a driven slider that moves along the central axis; and a synchronous linkage mechanism connecting the driven slider and the wheel arm assembly; one end of the wheel arm assembly is pivotally connected to the outer wall of the central main housing; the synchronous linkage mechanism is used to convert the axial linear motion of the driven slider into the swinging motion of the wheel arm assembly synchronously opening or closing around its pivot end.

[0009] Preferably, the lead screw drive mechanism further includes: an extension drive motor fixed at one end of the central main body housing for driving the central drive lead screw to rotate; and a guide rod arranged parallel to the central drive lead screw, the guide rod passing through the driven slider for guiding the linear motion of the driven slider and preventing it from rotating; the main arm is an L-shaped rod, the short end of which is hinged to the wheel arm mounting base, and the wheel fork is fixedly connected to the end of the long side of the main arm.

[0010] Preferably, the synchronous linkage mechanism includes: a main linkage with one end hinged to the driven slider; a secondary linkage with one end hinged to the wheel arm assembly; and a linkage center pivot that hinges the main linkage and the secondary linkage together at their middle parts; a linkage fixing fulcrum is provided on the outer wall of the central main body housing, and the linkage center pivot is pivotally mounted on the linkage fixing fulcrum.

[0011] Preferably, the boom assembly includes: a main boom, one end of which is hinged to a boom mounting base on the outer wall of the central main body chassis; a wheel fork fixed to the other end of the main boom; and a wheel rotatably mounted on the wheel fork, the wheel having a hub drive motor inside for driving its rotation.

[0012] Prior to this, the outer edge of the wheel is fitted with a high-friction tire, and the surface of the high-friction tire is provided with a tread pattern.

[0013] Preferably, the central main chassis is a hollow cylindrical structure, with its two ends sealed by a front flange and a rear flange, respectively; the two ends of the central drive screw are rotatably mounted on the front flange and the rear flange by bearings, respectively.

[0014] Preferably, the device also includes a mission payload module, which is mounted on the outside of the front flange.

[0015] Preferably, the mission payload module includes: a high-definition camera mounted at the center of the front flange; and an LED lighting array arranged around the high-definition camera.

[0016] Preferably, the two ends of the guide rod are fixedly connected to the inner side of the front flange and the inner side of the rear flange, respectively.

[0017] Alternatively, a detection method for a culvert detection device is also provided, comprising the following steps: S1. Place the culvert inspection device at the culvert entrance, ensuring that the hollow cylindrical structure of the central main unit is placed horizontally and sealed at both ends by the front and rear flanges; start the extension drive motor, drive the central drive screw to rotate, and drive the driven slider to move axially along the guide rod to the initial position, so that the synchronous linkage mechanism is in the retracted state. At this time, the main arm of the wheel arm assembly retracts inward around the wheel arm mounting base, and the wheels are close to the outer wall of the central main unit, making it easier for the device to enter the narrow culvert space. S2. Control the extension drive motor to rotate in the opposite direction. The central drive screw drives the driven slider to move along the guide rod away from the extension drive motor. The driven slider pulls the connecting rod center shaft to rotate around the connecting rod fixed fulcrum through the main connecting rod. At the same time, it drives the auxiliary connecting rod to push the main arm of the wheel arm assembly to swing outward around the wheel arm mounting base until the wheel contacts the inner wall of the culvert and forms a stable support. At this time, the short side and long side of the L-shaped main arm form a fixed angle to ensure that the high friction tire of the wheel is in close contact with the culvert wall. The tread surface enhances the grip and prevents the device from slipping. S3. Start the hub drive motor to drive the wheels to rotate and move the device along the culvert axis. During the movement, the high-definition camera collects real-time images of the culvert interior through the opening at the center of the front flange. An LED lighting array surrounds the high-definition camera to provide uniform illumination to eliminate shadows. The task load module transmits the image data to the external control terminal to simultaneously monitor defects such as cracks and water seepage on the inner wall of the culvert. The parallel arrangement of the guide rod and the central drive screw ensures smooth linear movement of the driven slider and avoids deviation when the wheel arm assembly is deployed. S4. When the cross-sectional dimensions of the culvert change or an obstacle is encountered, the movement distance of the driven slider is controlled by adjusting the speed of the extension drive motor, thereby fine-tuning the extension range of the wheel arm assembly. If it is necessary to reduce the volume to pass through a narrow section, the driven slider is driven to move back to the initial position, and the wheel arm assembly retracts. If it is necessary to increase the support force to cross a pit, the driven slider is driven to move further outward to widen the wheel spacing. The pivot design of the connecting rod center pivot and the connecting rod fixed fulcrum of the synchronous linkage mechanism ensures the synchronous movement of the wheel arm assembly and avoids unilateral jamming. S5. After the inspection task is completed, stop the hub drive motor, control the extension drive motor to drive the driven slider back to the initial position, and the wheel arm assembly is fully retracted to the outer periphery of the central main body; turn off the high-definition camera and LED lighting array, and disconnect the data transmission of the task load module; remove the device from the culvert, check the wear of the high-friction tires and the connection status of each component, clean the adhering substances on the wheel surface, and prepare for the next inspection; the entire process achieves efficient and stable culvert internal inspection through the coordinated work of the screw drive mechanism and the synchronous linkage mechanism.

[0018] Compared with the prior art, the present invention provides a method and apparatus for detecting culverts, which has the following beneficial effects: 1. This invention, by setting a lead screw drive mechanism inside the central main body chassis and a synchronous linkage mechanism linked thereto, enables the synchronous and precise control of the opening and closing movements of all wheel arm assemblies through a single extension drive motor. This allows the device to quickly adjust its outer diameter to adapt to culverts of different diameters and ensures that the wheels are always in close contact with the pipe wall with uniform pressure. This achieves the effect of quickly adapting to culverts of different diameters and maintaining stable support, greatly improving the environmental adaptability and operational stability of the device.

[0019] 2. This invention achieves effective physical protection for these key moving mechanisms by completely integrating the core and precision transmission components, such as the lead screw drive mechanism and the driven slider, into a central main body housing sealed by front and rear flanges. This isolates them from the harsh working environment inside the culvert (such as mud, water, and corrosive substances), thereby avoiding wear and corrosion, significantly improving the reliability of the equipment, and extending the service life of the entire machine.

[0020] 3. This invention employs a synchronous linkage mechanism consisting of a main connecting rod, a secondary connecting rod, and a fixed connecting rod center pivot, which cleverly and efficiently converts the single axial linear motion of the driven slider into synchronous radial oscillation of multiple wheel arm assemblies around their respective pivot points. This mechanism has a simple and compact structure, a short transmission chain, reliable motion, and is easy to process and maintain, thereby achieving the effects of simplifying the overall mechanical structure, reducing manufacturing costs, and reducing potential failure points.

[0021] 4. By independently setting a hub drive motor in each wheel, the present invention provides a powerful and independent driving force for the device's movement. This not only realizes four-wheel or multi-wheel drive and enhances the ability to climb slopes and overcome obstacles, but also enables flexible differential steering by controlling the speed difference between the wheels on different sides. At the same time, this driving method highly integrates the drive unit inside the wheel, greatly optimizing the spatial layout, thereby improving the device's mobility and ability to pass through complex terrain. Attached Figure Description

[0022] Figure 1This is a three-dimensional first view of an embodiment of the present invention; Figure 2 This is a perspective sectional view of one embodiment of the present invention; Figure 3 This is a three-dimensional exploded view of an embodiment of the present invention; Figure 4 This is a top sectional view of an embodiment of the present invention; Figure 5 This is a perspective front view of an embodiment of the present invention; Figure 6 This is a two-dimensional second view of an embodiment of the present invention; Figure 7 This is a partial structural cross-sectional view of the central main chassis in one embodiment of the present invention; Figure 8 This is a schematic diagram of a partial connection structure of the wheel arm assembly in one embodiment of the present invention.

[0023] Component numbering list in the diagram: 1. Central main chassis; 11. Front flange; 12. Rear flange; 13. Wheel arm mounting base; 2. Screw drive mechanism; 21. Extension drive motor; 22. Coupling; 23. Central drive screw; 24. Driven slider; 25. Guide rod; 3. Synchronous linkage mechanism; 31. Main connecting rod; 32. Secondary connecting rod; 33. Connecting rod center shaft; 34. Connecting rod fixed support point; 4. Wheel arm assembly; 41. Main arm; 42. Wheel fork; 43. Wheel hub drive motor; 44. Wheel; 45. High-friction tire; 5. Task load module; 51. High-definition camera; 52. LED lighting array. Detailed Implementation

[0024] Next, we will focus on the lead screw drive mechanism 2 located inside the central main chassis 1. Please refer to... Figure 2 , Figure 4 and Figure 7The lead screw drive mechanism 2 is the core power source and transmission mechanism for realizing the opening and closing movements of the wheel arm. It includes an extension drive motor 21, which is fixed to the inside of the rear flange 12 by a mounting bracket. The extension drive motor 21 is preferably a servo motor or stepper motor with an encoder to achieve precise control of the rotation angle and position. The output shaft of the motor is connected to one end of the central drive lead screw 23 via a coupling 22. The central drive lead screw 23 is a key component of the transmission system and is preferably a high-efficiency ball screw, which is arranged along the geometric center axis of the central main body housing 1. The two ends of the lead screw are precisely mounted in the center holes of the front flange 11 and the rear flange 12 by deep groove ball bearings, respectively, to ensure smooth and low-resistance rotation. A driven slider 24 engages with the thread of the central drive lead screw 23. The driven slider 24 has an internal thread structure that matches the lead screw, usually a ball screw nut. Therefore, when the extension drive motor 21 drives the central drive screw 23 to rotate, the driven slider 24 will reciprocate linearly along the axial direction under the guidance of the screw. To prevent the driven slider 24 from rotating with the screw and failing to generate axial displacement, and to ensure the smoothness and accuracy of its linear motion, the device is also equipped with at least one guide rod 25. The guide rod 25 is a precision cylindrical rod with a smooth surface, and its two ends are fixed to the inner walls of the front flange 11 and the rear flange 12 respectively, and kept strictly parallel to the central drive screw 23. The driven slider 24 is machined with a through hole that precisely matches the guide rod 25, and the guide rod 25 passes through the through hole. In this way, the guide rod 25 provides the driven slider 24 with anti-torsional constraint and precise motion guide.

[0025] The device is deployed at the culvert entrance, in its initial state as follows: Figure 6As shown, all wheel arm assemblies 4 are in the retracted state. The operator starts the extension drive motor 21 through the control system. Assuming the motor rotates in the forward direction, it drives the central drive screw 23 to rotate through the coupling 22. Driven by the screw and constrained by the guide rod 25, the driven slider 24 moves smoothly in a straight line towards the front flange 11. The movement of the driven slider 24 pulls the lower ends of all the main connecting rods 31 that are hinged to it. Since the middle part of the main connecting rod 31 is fixed to the connecting rod fixed fulcrum 34 by the connecting rod central pivot 33, the main connecting rod 31 will rotate around the fulcrum. The movement of the upper end of the main connecting rod 31 is transmitted to the main arm 41 through the secondary connecting rod 32, pushing the main arm 41 to swing outward around its pivot point on the wheel arm mounting base 13. This process continues, and all wheel arm assemblies 4 open synchronously and smoothly until the high-friction tires 45 on the wheels 44 at their ends are tightly pressed against the inner wall of the culvert. At this time, the contact pressure can be determined by monitoring the current value of the extension drive motor 21. Once the preset value is reached, the motor stops, thereby achieving firm and stable multi-point support for the inner wall of the culvert. Conversely, when the extension drive motor 21 rotates in the opposite direction, the driven slider 24 moves backward, and the wheel arm assembly 4 is synchronously retracted through the linkage mechanism.

[0026] Once the device is stably supported inside the culvert, the operator activates each wheel hub drive motor 43. All motors rotate synchronously in the same direction, driving the wheels 44 to roll, thus propelling the entire device smoothly forward or backward within the culvert. During movement, the high-definition camera 51 at the front captures real-time video images of the culvert's interior and transmits them to the ground control console via cable or wirelessly, while the LED lighting array 52 provides continuous illumination. If steering is required, the control system can apply different speeds to the wheel hub drive motors 43 on the left and right sides of the device, utilizing differential speed principles to achieve flexible steering.

[0027] Finally, it should be noted that the basic concepts have been described above. Obviously, for those skilled in the art, the detailed disclosure above is merely illustrative and does not constitute a limitation of this specification. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this specification. Such modifications, improvements, and corrections are suggested in this specification, and therefore remain within the spirit and scope of the exemplary embodiments of this specification. Furthermore, this specification uses specific terms to describe embodiments of this specification. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a feature, structure, or characteristic associated with at least one embodiment of this specification. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of this specification can be appropriately combined. Moreover, unless expressly stated in the claims, the order of processing elements and sequences, the use of numbers and letters, or other names described in this specification are not intended to limit the order of the processes and methods of this specification.

[0028] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A culvert inspection device, comprising a central main housing (1) and a wheel arm assembly (4) disposed on the outer periphery of the central main housing (1), characterized in that, Also includes: A lead screw drive mechanism (2) is provided inside the central main body housing (1); the lead screw drive mechanism (2) includes a central drive lead screw (23) arranged along the central axis of the central main body housing (1) and a driven slider (24) that moves along the central axis. And, a synchronous linkage mechanism (3) connecting the driven slider (24) and the wheel arm assembly (4); One end of the wheel arm assembly (4) is pivotally connected to the outer wall of the central main body chassis (1); The synchronous linkage mechanism (3) is used to convert the axial linear motion of the driven slider (24) into the swinging motion of the wheel arm assembly (4) around its pivot end.

2. The culvert inspection device according to claim 1, characterized in that, The lead screw drive mechanism (2) also includes: An extension drive motor (21) fixed at one end of the central main body housing (1) is used to drive the central drive screw (23) to rotate. In addition, a guide rod (25) is arranged parallel to the central drive screw (23), the guide rod (25) passes through the driven slider (24), and is used to guide the linear motion of the driven slider (24) and prevent it from rotating.

3. The culvert inspection device according to claim 1, characterized in that, The synchronous linkage mechanism (3) includes: One end of the main connecting rod (31) is hinged to the driven slider (24); A secondary connecting rod (32) with one end hinged to the wheel arm assembly (4); And a connecting rod center pivot (33) that hinges the main connecting rod (31) and the secondary connecting rod (32) together at the middle. A connecting rod fixing point (34) is provided on the outer wall of the central main chassis (1), and the connecting rod center pivot (33) is pivotally mounted on the connecting rod fixing point (34).

4. The culvert inspection device according to claim 1, characterized in that, The wheel arm assembly (4) includes: Main arm (41), one end of which is hinged to the wheel arm mounting base (13) on the outer wall of the central main body chassis (1); The wheel fork (42) is fixed to the other end of the main arm (41); And, a wheel (44) mounted on the wheel fork (42) is rotatably mounted on the wheel fork (42), and a hub drive motor (43) for driving its rotation is provided inside the wheel (44). The main arm (41) is an L-shaped rod with its short end hinged to the wheel arm mounting base (13), and the wheel fork (42) is fixedly connected to the end of the long side of the main arm (41).

5. The culvert inspection device according to claim 4, characterized in that, The outer edge of the wheel (44) is fitted with a high-friction tire (45), and the surface of the high-friction tire (45) is provided with a tread pattern.

6. The culvert inspection device according to claim 1, characterized in that, The central main chassis (1) is a hollow cylindrical structure, and its two ends are sealed by the front flange (11) and the rear flange (12) respectively; the two ends of the central drive screw (23) are rotatably mounted on the front flange (11) and the rear flange (12) respectively by bearings.

7. The culvert inspection device according to claim 6, characterized in that, The device also includes a mission payload module (5), which is mounted on the outside of the front flange (11).

8. The culvert inspection device according to claim 7, characterized in that, The mission payload module (5) includes: A high-definition camera (51) is installed at the center of the front flange (11); And an LED lighting array (52) arranged around the high-definition camera (51).

9. The culvert inspection device according to claims 2 and 6, characterized in that, The two ends of the guide rod (25) are fixedly connected to the inner side of the front flange (11) and the inner side of the rear flange (12), respectively.

10. The detection method of the culvert detection device according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Place the culvert detection device at the culvert entrance, ensuring that the hollow cylindrical structure of the central main body box (1) is placed horizontally and sealed at both ends by the front flange (11) and the rear flange (12); start the extension drive motor (21), drive the central drive screw (23) to rotate, and drive the driven slider (24) to move axially along the guide rod (25) to the initial position, so that the synchronous linkage mechanism (3) is in the retracted state. At this time, the main arm (41) of the wheel arm assembly (4) retracts inward around the wheel arm mounting base (13), and the wheel (44) is close to the outer wall of the central main body box (1), making it easier for the device to enter the narrow culvert space; S2. Control the extension drive motor (21) to rotate in the opposite direction, and the central drive screw (23) drives the driven slider (24) to move away from the extension drive motor (21) along the guide rod (25); the driven slider (24) pulls the connecting rod center shaft (33) to rotate around the connecting rod fixed fulcrum (34) through the main connecting rod (31), and simultaneously drives the auxiliary connecting rod (32) to push the main arm (41) of the wheel arm assembly (4) to swing outward around the wheel arm mounting base (13) until the wheel (44) contacts the inner wall of the culvert and forms a stable support; at this time, the short side and the long side of the L-shaped main arm (41) form a fixed angle to ensure that the high friction tire (45) of the wheel (44) is in close contact with the culvert wall, and the tread surface enhances the grip and prevents the device from sliding; S3. Start the hub drive motor (43) to drive the wheel (44) to rotate and drive the device to move along the culvert axis. During the movement, the high-definition camera (51) collects images of the inside of the culvert in real time through the opening at the center of the front flange (11). The LED lighting array (52) is arranged around the high-definition camera (51) to provide uniform lighting to eliminate shadows. The task load module (5) transmits the image data to the external control terminal and monitors defects such as cracks and seepage in the inner wall of the culvert in real time. The parallel arrangement of the guide rod (25) and the central drive screw (23) ensures that the driven slider (24) moves smoothly in a straight line and avoids the wheel arm assembly (4) from deflecting when it is deployed. S4. When the cross-sectional dimensions of the culvert change or an obstacle is encountered, the movement distance of the driven slider (24) is controlled by adjusting the speed of the extension drive motor (21), thereby finely adjusting the unfolding range of the wheel arm assembly (4). If it is necessary to reduce the volume to pass through the narrow section, the driven slider (24) is driven to move to the initial position and the wheel arm assembly (4) retracts. If it is necessary to increase the support force to cross the pit, the driven slider (24) is driven to move further outward to expand the wheel (44) spacing. The pivot design of the connecting rod center pivot (33) and the connecting rod fixed fulcrum (34) of the synchronous linkage mechanism (3) ensures that the wheel arm assembly (4) moves synchronously and avoids unilateral jamming. S5. After the inspection task is completed, stop the hub drive motor (43), control the extension drive motor (21) to drive the driven slider (24) back to the initial position, and the wheel arm assembly (4) is completely retracted to the outer periphery of the central main body box (1); turn off the high-definition camera (51) and LED lighting array (52), and disconnect the data transmission of the task load module (5); take the device out of the culvert, check the wear of the high friction tire (45) and the connection status of each component, clean the attachments on the surface of the wheel (44), and prepare for the next inspection; the whole process achieves efficient and stable culvert internal inspection through the coordinated work of the screw drive mechanism (2) and the synchronous linkage mechanism (3).

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