A steerable wheel set for walking on a circular surface

Abstract

The utility model relates to a variable direction wheel set for walking on a round curved surface, a machine body, side plates fixedly connected to the both sides of the bottom of the machine body, a wheel set fixed side plate connected to the other end of the connecting side plate, a driving motor arranged on one side of the driving wheel, a motor output shaft in transmission connection with the driving wheel axle, and an elastic track sleeved between the driving wheel and the driven wheel.

Description

Technical Field

[0001] This utility model belongs to the technical field of variable direction wheel sets, and relates to a variable direction wheel set for walking on curved surfaces. Background Technology

[0002] In fields such as building engineering inspection and shield tunnel construction, wall-climbing robots and infrastructure equipment often need to perform mobile operations on curved surfaces. As the core component in contact with the working surface, the wheel assembly's adaptability to curved surfaces directly determines the efficiency and safety of the operation. With the increasing diversity of building shapes, the demand for operations on complex curved surfaces such as small-radius arc surfaces and cylindrical surfaces is growing. Wheel assemblies with variable direction and surface adaptation functions have become a key technical support for related equipment. They need to achieve dynamic adaptation to curved surfaces with different curvatures to ensure smooth equipment movement and precise operation.

[0003] However, traditional wheel sets have significant technical drawbacks when traveling on curved surfaces. The driven wheels of traditional wheel sets are mostly fixed installations, unable to dynamically adjust their position and angle according to changes in the curvature of the curved surface. This leads to gaps and poor contact between the track and the surface. This problem not only causes slippage and deviation during movement, affecting stability and operational accuracy, but can also exacerbate track wear due to uneven stress, reducing the equipment's lifespan. This issue is even more pronounced in small-radius curved surface operations, potentially causing safety hazards such as equipment tipping over, severely limiting the application of such equipment in complex curved surface environments.

[0004] After reviewing relevant materials, several technical solutions have been found for improving wheel sets for curved surfaces. Among them, patent CN104564133A, titled "A Curved Surface Traveling Universal Wheel," describes a method that uses an open groove in the middle of a crossbeam. A first and second pin, perpendicular to each other, are installed at the top and bottom of a base within the groove. By utilizing the left-right swinging of the base and the construction equipment frame along the first pin and the back-and-forth swinging of the base and the crossbeam along the second pin, the force of the roller is ensured to always be perpendicular to the curved surface of the tunnel segment. The advantages of this patent are its simple structure, high reliability, and ability to allow equipment to operate on curved surfaces without the need for temporary tracks, thus shortening the construction cycle. However, its disadvantages include its limitation to individual universal wheels, making it difficult to form a coordinated wheel set, and the lack of a track-fitting structure, resulting in insufficient stability under large loads or on complex curved surfaces, and failing to solve the problem of loose track-to-surface contact. Another common approach is to use a combination of multiple independently suspended omnidirectional wheels. Each wheel adapts to the curved surface through independent oscillation. Its advantage is the ability to distribute load and adapt to surfaces with moderate curvature. However, its disadvantages include the difficulty in coordinating and controlling the wheel assembly, uneven stress between the track and the wheels, insufficient sensitivity to changes in the curvature of the curved surface, and persistent poor walking stability. Furthermore, some solutions improve fit by adding track tensioning devices, but this only adjusts track tension and cannot fundamentally solve the core problem of the mismatch between the driven wheel position and the surface curvature, resulting in limited improvement in adaptability. A comprehensive analysis of existing technologies reveals that the dynamic oscillation adaptation principle provides an important approach to curved surface contact; however, none of the existing solutions effectively integrates the active dynamic position adjustment of the driven wheels in the wheel assembly with the track structure. Therefore, this utility model draws on the core logic of dynamic adaptation and adopts a structure that combines an arc-shaped sliding groove with a rotation drive device to achieve active dynamic adjustment of the driven wheel position. Combined with an elastic track, it ensures a close fit with the curved surface, ultimately solving the adaptation and stability problems of traditional wheel sets when walking on curved surfaces. Utility Model Content

[0005] This invention provides a variable-direction wheel set for walking on curved surfaces, solving the technical problem that traditional wheel sets are difficult to dynamically adjust the position of the driven wheel to adapt to changes in the curvature of the curved surface when walking on curved surfaces, resulting in poor track fit and poor walking stability.

[0006] To solve the above problems, the technical solution adopted by the utility model is as follows: A variable-direction wheel assembly for walking on curved surfaces includes a machine body. Connecting side plates are fixed to both sides of the bottom of the machine body. A wheel assembly fixing side plate is fixedly connected to the end of the connecting side plate away from the machine body. A driving wheel and a driven wheel are rotatably connected to the wheel assembly fixing side plate. An arc-shaped sliding groove is formed on the wheel assembly fixing side plate corresponding to the driven wheel. Sliding blocks are fixed to both ends of the driven wheel's axle, and the sliding blocks slide in engagement with the arc-shaped sliding groove. A rotation drive device is also fixed to the wheel assembly fixing side plate. A rotating rod is connected to the output end of the rotation drive device. The end of the rotating rod away from the rotation drive device is hinged to the driven wheel's axle. A drive motor is provided on one side of the driving wheel, and the output shaft of the drive motor is drively connected to the driving wheel's axle. An elastic track is fitted between the driving wheel and the driven wheel.

[0007] The principle and advantages of this scheme are as follows: The machine body is stably supported by connecting side plates and wheel assembly fixed side plates. The drive wheel, powered by a drive motor, provides the walking force, while the elastic track enables power transmission and surface contact between the drive and driven wheels. An arc-shaped sliding groove on the wheel assembly fixed side plate provides an arc-shaped movement trajectory for the driven wheel. Sliding blocks at both ends of the driven wheel axle engage with the arc-shaped sliding groove, limiting the driven wheel's movement path. Simultaneously, a rotation drive device is hinged to the driven wheel axle via a rotating rod. This rod can extend, retract, or rotate according to changes in the curvature of the curved surface, thereby causing the driven wheel to adjust its position and angle along the arc-shaped sliding groove in real time. This design allows the driven wheel to dynamically adapt to curved surfaces with different curvatures, ensuring the elastic track always remains in contact with the curved surface, avoiding gaps or uneven force, and providing stable support for the equipment's movement.

[0008] Compared to existing technologies, which can only achieve the oscillation adaptation of a single wheel and cannot achieve coordinated work between the wheel assembly and the track, resulting in insufficient stability under complex curvature surfaces or large loads, this solution addresses the challenges of complex coordination and poor track fit by using a combination of multiple independent suspension omnidirectional wheels. This solution, through the linkage design of an arc-shaped sliding groove and a rotation drive device, achieves active dynamic adjustment of the driven wheel position. Compared to the passive adaptation of existing technologies, it offers a faster response, higher adaptation accuracy, and can precisely handle complex scenarios such as small-radius circular surfaces and variable curvature surfaces. Furthermore, the combination of elastic tracks and dynamically adjustable driven wheels ensures a tight fit between the tracks and curved surfaces, completely solving the problems of slippage and deviation associated with traditional wheel sets. For example, in the scenario of inspecting cylindrical bridge supports, the equipment's travel deviation can be reduced to the millimeter level, significantly improving operational accuracy. The active dynamic adjustment structure reduces track wear and extends the equipment's service life. Compared to traditional fixed wheel sets, the track replacement cycle can be extended. Moreover, this solution does not require additional track laying or modification of the working surface, making it more widely applicable. It can adapt to different types of curved surfaces, such as convex and concave surfaces, and can also meet the installation requirements of various equipment, such as wall-climbing robots and infrastructure equipment, significantly reducing construction and inspection costs.

[0009] Furthermore, the sliding groove is an arc-shaped sliding groove, which is connected to the driven wheel. The geometric characteristics of the circular surface determine that the tangent direction at any point on its surface changes with the curvature. If a straight sliding groove is used, the driven wheel can only move along a fixed straight trajectory, which cannot match the arc contour of the surface, easily leading to gaps or excessive local compression between the track and the surface. The curvature design of the arc-shaped sliding groove can match the curvature range of the target conforming circular surface, guiding the driven wheel to adjust its position along an arc path that conforms to the surface contour, avoiding displacement or jamming of the driven wheel. At the same time, the cooperation between the arc-shaped sliding groove and the sliding blocks at both ends of the driven wheel axle restricts the driven wheel to move only within the preset arc trajectory, preventing lateral displacement or angular misalignment during the force process, ensuring the relative position between the driven wheel and the driving wheel is stable, and thus ensuring that the elastic track is always taut and in contact with the surface. For example, when a wall-climbing robot is inspecting a cylindrical support, the arc-shaped sliding groove can guide the driven wheel to adjust its height and angle in real time according to the curvature of the cylindrical surface, so that the track always fits completely against the cylindrical surface. This avoids the track from being partially suspended or experiencing increased wear due to improper trajectory constraints, and provides reliable structural support for the equipment to move smoothly on the curved surface.

[0010] Furthermore, the rotary drive device is positioned at the center of the sliding groove. This rotary drive device has a forward and reverse rotation structure. The center of the arc-shaped sliding groove is the reference point for the arc-shaped trajectory. When the rotary drive device is located at this position, the rotating rod connected to its output end can be considered as the radius extending from the center to the driven wheel axle. The forward and reverse rotation of the rotating rod can directly drive the driven wheel to move in a circular trajectory along the arc-shaped sliding groove. No additional guide correction structure is needed to ensure that the driven wheel always fits the sliding groove trajectory, avoiding adjustment jamming or trajectory deviation caused by the offset of the rotation center, and significantly improving adjustment accuracy. For example, when adapting to circular curved surfaces with different radii, if it is necessary to increase the distance between the driven wheel and the driving wheel to fit a large curvature convex surface, the forward rotation of the rotary drive device can drive the rotating rod to push the driven wheel to move outward along the arc-shaped groove; if it is necessary to decrease the distance to fit a concave surface, the reverse rotation can pull the driven wheel to move inward. The entire adjustment process does not require changing the relative position of the rotary drive device and the sliding groove, making operation convenient and responsive. In addition, the forward and reverse structure gives the driven wheel bidirectional adjustment capability, which can not only adapt to circular surfaces with fixed curvature, but also cope with the real-time changes of curved surfaces with variable curvature, such as elliptical surfaces and irregular arc surfaces. Compared with the unidirectional adjustment structure, it has a wider range of adaptability and stronger practicality. At the same time, the design of the coincidence of the rotation center and the center of the sliding groove can minimize the force loss of the rotating rod and reduce the noise of the device and the wear of the components.

[0011] Furthermore, a surface curvature sensor is installed on one side of the wheel assembly's fixed side plate. This surface curvature sensor is a four-core fiber optic curvature sensor, and its detection direction is consistent with the walking direction of the wheel assembly. Compared with traditional mechanical or single-core fiber optic sensors, the four-core fiber optic curvature sensor has higher detection accuracy and anti-interference capability. It accurately calculates the surface curvature through the light intensity changes of the multi-core fiber, which can effectively avoid the interference of construction environment factors such as dust and vibration on the detection results, ensuring the authenticity and stability of curvature data. By keeping the detection direction consistent with the walking direction, the sensor can perceive the curvature state of the surface that the equipment is about to contact in advance, rather than just detecting the current contact position. This allows sufficient response time for the driven wheel to adjust. For example, when the wall-climbing robot detects a variable curvature cylindrical surface, the sensor can detect the slight change in the curvature of the surface in front 0.5 to 1 second in advance and transmit the signal to the control system, so that the rotation drive device can promptly drive the driven wheel to adjust its position along the arc-shaped sliding groove, avoiding loose track contact due to adjustment lag. In addition, this design can achieve real-time quantitative feedback of curvature changes. The control system can automatically calculate the angle and displacement that the driven wheel needs to be adjusted based on the precise curvature parameters output by the sensor. Compared with the traditional adjustment method that relies on manual judgment or preset parameters, it not only greatly improves the adaptation accuracy, but also adapts to more circular surface scenarios with unknown curvature, without the need to readjust the equipment for different surfaces.

[0012] Furthermore, a curved surface contact pressure monitoring sensor is installed on the inner side of the track. This sensor is a thin-film pressure sensor, arranged at 20-30mm intervals along the track length. It can capture the contact pressure distribution between the track and the curved surface in real time and comprehensively, providing accurate closed-loop feedback for the dynamic adjustment of the driven wheel. This ensures that the track always contacts the curved surface with optimal pressure and provides timely warnings of abnormal stress risks. From the perspective of sensor characteristics, the thin-film pressure sensor has the advantages of thinness and high flexibility, which can closely fit the arc contour of the inner side of the track and synchronously sense pressure changes with track deformation. This avoids the impact of excessive sensor rigidity on normal track movement or pressure detection deviation. The 20-30mm interval arrangement ensures both the coverage density of pressure monitoring (this spacing is smaller than the contact width between the track and the curved surface in most curved surface operation scenarios, enabling pressure distribution monitoring without blind spots) and avoids cost waste and signal redundancy caused by overly dense sensors. When a certain area of ​​the track experiences excessively loose (low pressure) or excessively tight (high pressure) contact due to improper adjustment of the driven wheels, the corresponding sensor transmits pressure data to the control system in real time. If the pressure in a certain section of the track is detected to be below a threshold, the system can drive the rotating drive device to adjust the position of the driven wheels, increasing the track tension in that area to improve contact and prevent slippage. If the pressure in a certain section is above the threshold, the track can be appropriately loosened to prevent excessive compression that could lead to accelerated track wear or surface damage. For example, when a wall-climbing robot is detecting a small-radius cylindrical convex surface, uneven pressure can easily occur at the upper and lower ends of the track due to changes in curvature. Based on the pressure distribution data fed back by the sensors, the driven wheels can adjust their height accordingly.

[0013] Furthermore, pressure sensors are installed inside the drive and driven wheels. These pressure sensors are miniature piezoresistive pressure sensors, with 3 to 4 sensors evenly arranged along the circumference of the gears of the drive and driven wheels. Miniature piezoresistive pressure sensors are small in size and have a fast response speed, making them suitable for the compact space of the gears and avoiding interference with the meshing motion of the gear teeth. The design of 3 to 4 sensors evenly arranged along the circumference provides comprehensive coverage of the force on the circumference of the wheel body. The spacing between the 3 to 4 sensors ensures that there is always a sensor in an effective monitoring position during the wheel's rotation, eliminating blind spots. Furthermore, by comparing data from multiple sensors, it is possible to accurately determine whether there are localized issues such as excessive tightness, looseness, or misalignment in the meshing of the gear teeth and the track. In actual operation, when the drive wheel drives the track through the gears, if the meshing pressure between the gear teeth and the track in a certain area is too low, it may lead to slippage and power transmission loss; if the pressure is too high, it will exacerbate the wear of the gear teeth and the track, and may even cause deformation of the tooth surface. At this point, the pressure sensors at the corresponding locations can feed data back to the control system in real time. If uneven pressure is detected, the system can optimize the meshing state of the wheel teeth and tracks by fine-tuning the speed of the drive motor or the position of the driven wheel, ensuring stable power transmission. Simultaneously, by monitoring pressure data over a long period, the system can predict the wear trend of the wheel teeth or tracks. For example, if a sensor detects a persistently abnormal pressure value, it can provide an early warning of component wear, preventing sudden malfunctions. For instance, during the climbing process of a wall-climbing robot climbing a curved surface, the wheels may experience a sudden increase in local meshing pressure due to changes in surface curvature. The sensor can detect the pressure anomaly within 0.1 seconds and trigger adjustment. Compared to traditional wheel sets without monitoring, this reduces the wear rate of the wheel teeth and tracks, while preventing equipment stalling or deviation due to poor meshing, significantly improving the reliability and durability of the equipment.

[0014] Furthermore, the height displacement of the driven wheel sliding in the sliding groove is less than the diameter radius of the driven wheel. While the driven wheel can dynamically adapt to the curvature changes of the circular surface, it avoids problems such as decreased stability of the wheel assembly structure, loss of track tension, or shift of the equipment's center of gravity due to excessive displacement. The diameter radius of the driven wheel is a key benchmark for its own structural stability: if the height displacement exceeds the radius, the driven wheel may tilt excessively during sliding, resulting in an increased clearance between the wheel axle and the sliding groove, causing shaking or jamming, or even uneven force on the wheel assembly's fixed side plate. At the same time, excessive displacement will cause the center distance between the driving wheel and the driven wheel to change beyond the extension limit of the elastic track, either causing the track to become excessively loose and slip, or causing the track to become excessively tight, aggravating wear and destroying the stability of power transmission. When the displacement is controlled within the radius, the driven wheel can make a sufficient range of position adjustment along the arc-shaped sliding groove to adapt to the curvature change requirements in scenarios such as small-radius circular surfaces and variable curvature surfaces. For example, when the wall-climbing robot is inspecting a cylindrical component with a diameter of 1 meter, this displacement range is sufficient to allow the driven wheel to make real-time fine adjustments to the curvature of the cylindrical surface to ensure that the track makes gapless contact. At the same time, it can always maintain a reasonable meshing state between the wheel and the track, avoid the impact of sudden changes in center distance on track tension, and prevent the center of gravity of the equipment from shifting significantly due to excessive displacement of the driven wheel. Especially when operating on vertical or inclined circular surfaces, it can effectively reduce the risk of equipment tipping over.

[0015] Furthermore, the diameter of the driving wheel is twice that of the driven wheel. The larger diameter of the driving wheel results in better linear velocity and driving torque during rotation. With the same output power of the drive motor, the larger diameter driving wheel can transmit power to the track more smoothly through a larger contact area, reducing the force per unit area and reducing local wear on the track and wheel. At the same time, the larger torque of the driving wheel can better overcome the resistance when walking on curved surfaces and avoid motor overload. For example, when a wall-climbing robot climbs a cylindrical convex surface, the large diameter driving wheel can provide stronger traction to prevent the equipment from sliding down. From the perspective of surface adaptation and walking stability, the smaller diameter driven wheels are easier to adjust flexibly. Combined with the previous arc-shaped sliding groove design, the smaller diameter driven wheels require less adjustment space when sliding along the groove, and can more accurately adapt to the curvature changes of the circular surface, ensuring that the track always fits the surface. The larger diameter drive wheel has a more stable contact point with the surface and can serve as a support reference for the wheel assembly, reducing the overall shaking of the equipment caused by the fine adjustment of the driven wheels. For example, when walking on a circular surface with varying curvature, the large diameter drive wheel can maintain the stability of the equipment's direction of travel, while the small diameter driven wheel can quickly adapt to the curvature changes. The two work together to achieve a synergistic effect of stable guidance and flexible adaptation. In addition, the diameter ratio design of the drive wheel and driven wheel can also optimize the overall layout of the wheel assembly: the large drive wheel can increase the height of the equipment chassis and avoid being stuck by surface protrusions or obstacles during walking, while the small driven wheel reduces the overall weight and space occupied by the wheel assembly, which is especially suitable for weight- and volume-sensitive equipment such as wall-climbing robots.

[0016] Furthermore, the microprocessor is electrically connected to the curved surface contact pressure monitoring sensor, the pressure sensor, and the rotation drive device. It controls the rotation of the rotation drive device based on sensor data, thereby controlling the position of the driven wheel within the sliding groove. The microprocessor can collect monitoring data from two types of sensors in real time: the pressure distribution across the entire track and curved surface fed back by the curved surface contact pressure monitoring sensor, reflecting the overall contact state of the track and preventing localized suspension or excessive compression; and the tooth meshing pressure fed back by the pressure sensors on the inner sides of the drive and driven wheels, which can determine whether the power transmission is balanced, preventing slippage or component wear. The microprocessor quickly analyzes this data using a preset algorithm. For example, when the pressure in a certain area of ​​the track is detected to be below a threshold, it can determine that the contact in that area is too loose, then calculate the displacement that the driven wheel needs to adjust along the arc-shaped sliding groove, and then send a precise control signal to the rotation drive device, driving the rotating rod to move the driven wheel to the target position until the sensor-feedback pressure returns to a reasonable range. Compared to traditional solutions, this closed-loop control not only has a faster response speed but also achieves adaptive adjustment, handling complex scenarios such as variable curvature circular surfaces and curved obstacles without manual intervention. For example, when a wall-climbing robot is inspecting cylindrical components, if a tiny protrusion on the surface of the component causes a sudden increase in local pressure on the track, the microprocessor can identify the anomaly within 0.5 seconds and drive the driven wheel to make fine adjustments to avoid excessive wear of the track or equipment misalignment. At the same time, the microprocessor can also store historical data and optimize adjustment parameters through data analysis to further improve the adaptation accuracy. For example, it can automatically match the optimal adjustment strategy for curved surfaces with different curvatures without the need for repeated equipment debugging. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of this utility model.

[0018] Figure 2 This is a schematic diagram of the structure of this utility model.

[0019] Figure 3 This is a schematic diagram of the working principle of this utility model on a cylindrical surface.

[0020] Figure 4 This is a schematic diagram of the operation of this utility model on a curved surface. Detailed Implementation

[0021] The reference numerals in the accompanying drawings include: machine body 1, connecting side plate 2, wheel set fixing side plate 3, drive wheel 4, track 5, driven wheel 6, sliding groove 7, rotation drive device 8, rotating rod 9, fixed frame 10, drive motor 11, groove 12, pressure sensor 13, curved surface fitting pressure monitoring sensor 14, curved surface curvature sensor 15, slider 16, microprocessor 17. Example 1 like Figure 1-4As shown, a variable-direction wheel assembly for walking on curved surfaces includes a machine body 1. Two connecting side plates 2 are symmetrically fixed to the left and right sides of the bottom of the machine body 1 by bolts. The connecting side plates 2 are vertical, and their ends away from the machine body 1 are fixedly connected to the top of the wheel assembly fixing side plate 3 by welding. The wheel assembly fixing side plate 3 is a rectangular steel plate with a thickness of 10mm. The two wheel assembly fixing side plates 3 are arranged in parallel opposite directions, with a spacing equal to the width of the drive wheel 4.

[0022] A driving wheel 4 and a driven wheel 6 are rotatably connected to the fixed side plate 3 of the wheelset via bearings. The diameter of the driving wheel 4 is 200mm, and the diameter of the driven wheel 6 is 100mm. The driving wheel 4 is located at the lower part of the fixed side plate 3, and the driven wheel 6 is located above the driving wheel 4. An arc-shaped sliding groove 7 is provided on the fixed side plate 3 corresponding to the position of the driven wheel 6. The curvature of the sliding groove 7 matches the curvature range of the adaptable circular surface, and its central angle is 60°. The two ends of the axle of the driven wheel 6 are fixed with sliders 16 by flat keys. The sliders 16 are cylindrical structures, and their diameter is clearance-fitted with the width of the sliding groove 7. The sliders 16 can slide smoothly along the sliding groove 7, and the maximum height displacement of the driven wheel 6 along the sliding groove 7 is 40mm, which is less than its diameter radius of 50mm.

[0023] A fixing bracket 10 is bolted to the outer side of the wheel assembly fixing side plate 3. A rotation drive device 8 is installed on the fixing bracket 10. The rotation drive device 8 is a forward and reverse servo motor, which is located at the center of the sliding groove 7. The output shaft of the rotation drive device 8 is fixedly connected to one end of the rotating rod 9 through a coupling. The end of the rotating rod 9 away from the rotation drive device 8 is hinged to the wheel axle of the driven wheel 6 through a spherical bearing. The rotating rod 9 is made of alloy steel with a diameter of 12mm. It can extend and swing with the forward and reverse rotation of the rotation drive device 8, thereby driving the driven wheel 6 to adjust its position along the arc-shaped sliding groove 7.

[0024] A drive motor 11 is located on one side of the drive wheel 4. The drive motor 11 is fixed to the outside of the wheel assembly fixing plate 3 via a motor mount. The output shaft of the drive motor 11 is connected to the axle of the drive wheel 4 via a gearbox, which can drive the drive wheel 4 to rotate clockwise or counterclockwise. An elastic track 5 is fitted between the drive wheel 4 and the driven wheel 6. The track 5 is made of rubber and has an internal steel wire skeleton to enhance its toughness. The inner side of the track 5 has tooth grooves that are adapted to the teeth of the drive wheel 4 and the driven wheel 6.

[0025] A curved surface curvature sensor 15 is fixed to the outer center of the wheel assembly fixed side plate 3 by screws. This curved surface curvature sensor 15 is a four-core fiber optic curvature sensor, and its detection direction is consistent with the walking direction of the wheel assembly. Its signal output terminal is connected to the microprocessor 17 through a wire. Curved surface contact pressure monitoring sensors 14 are arranged at 25mm intervals along the length of the inner side of the track 5. These curved surface contact pressure monitoring sensors 14 are thin-film pressure sensors, and there are 8 of them. The detection surface of the sensor is in close contact with the inner side of the track 5, and the signal output terminal is connected to the microprocessor 17 through a wire passing through a wiring hole inside the track 5.

[0026] Both the driving wheel 4 and the driven wheel 6 have mounting grooves 12 on the inner side of their teeth. Pressure sensors 13 are embedded in the grooves 12. These pressure sensors are miniature piezoresistive pressure sensors. Three of them are evenly arranged on each wheel body and spaced 120° apart along the circumference of the wheel body. The detection end of the pressure sensor is flush with the tooth surface of the wheel. The signal output end is connected to the conductive slip ring inside the wheel axle through a wire, and then led out to the microprocessor 17 through the conductive slip ring.

[0027] The machine body 1 is equipped with a microprocessor 17, which is an STM32 series microcontroller. It is electrically connected to the curved surface curvature sensor 15, the curved surface fitting pressure monitoring sensor 14, the pressure sensor 13, the rotation drive device 8, and the drive motor 11 through wires. It can receive the detection data of each sensor in real time and output control signals according to the data.

[0028] The working process of this embodiment is as follows: Initialization phase: After the equipment is started, the microprocessor 17 controls the self-test of each sensor, the rotation drive device 8 drives the driven wheel 6 back to the middle initial position of the sliding groove 7, the drive motor 11 is in standby state, and the elastic track 5 is kept at a moderate tension.

[0029] Curvature detection and adjustment stage: When the wheel assembly begins to travel on the curved surface, the surface curvature sensor 15 detects the curvature data of the surface in front and transmits the data to the microprocessor 17. The microprocessor 17 calculates the required adjustment position of the driven wheel 6 based on the curvature parameters. If the surface is detected to be convex, the microprocessor 17 controls the rotary drive device 8 to rotate forward, driving the rotating rod 9 to push the driven wheel 6 upward along the sliding groove 7, increasing the distance between the driving wheel 4 and the driven wheel 6, so that the track 5 fits the convex surface; if the surface is detected to be concave, the rotary drive device 8 is controlled to rotate in reverse, pulling the driven wheel 6 downward to reduce the distance to adapt to the concave surface.

[0030] Pressure monitoring and closed-loop control stage: The curved surface contact pressure monitoring sensor 14 detects the contact pressure distribution between the track 5 and the curved surface in real time. If the pressure in a certain area is lower than the preset threshold (0.3MPa), the microprocessor 17 determines that the contact in that area is too loose and controls the rotation drive device 8 to fine-tune the position of the driven wheel 6 to increase the tension of the track 5 in that area. If the pressure is higher than the preset threshold (1.0MPa), the track 5 is appropriately loosened to avoid excessive compression. At the same time, the pressure sensors 13 on the inner side of the drive wheel 4 and the driven wheel 6 monitor the meshing pressure between the wheel teeth and the track 5. If uneven pressure is detected, the microprocessor 17 fine-tunes the speed of the drive motor 11 or the position of the driven wheel 6 to optimize the meshing state and ensure stable power transmission.

[0031] During the walking phase: The drive motor 11 starts, driving the drive wheel 4 to rotate, and transmitting power to the driven wheel 6 through the track 5, enabling the wheel set to walk smoothly on the curved surface. During the walking process, the sensors continuously monitor data, and the microprocessor 17 adjusts the rotation drive device 8 in real time according to the changes in surface curvature and pressure feedback, so that the driven wheel 6 dynamically adapts to the curved surface, ensuring that the track 5 always closely fits the curved surface and avoids slippage or deviation.

[0032] Example 2 The difference between this embodiment and embodiment one is that the curved surface contact pressure monitoring sensors 14 on the inner side of the track 5 are spaced 20mm apart and number 10, resulting in denser detection coverage; 4 pressure sensors 13 are arranged on the inner side of the drive wheel 4 and the driven wheel 6, spaced 90° apart along the circumference of the wheel body, with no blind spots; the rotating rod 9 is made of carbon fiber, which is lighter and has a faster transmission response.

[0033] The connection between the side plate 2 and the machine body 1 adopts a double positioning flange + quick-locking pin structure. Twelve evenly distributed positioning holes are opened on the flange. After the side plate 2 is initially fixed with four bolts, two quick-locking pins are inserted to complete precise positioning. Loosening the bolts and pins allows the side plate 2 to rotate 180° around the bottom axis of the machine body 1, enabling the entire wheel assembly to be switched between forward and reverse mounting. Before starting the operation, the operator inputs the target path information through the path planning terminal: if the object to be detected is a convex surface, such as the outer side of a bridge column or the outer wall of a storage tank, the radius of curvature is entered as 1m to 5m and the path length as 10m; if it is a concave surface, such as the inner side of a pipe or the curved inner wall of a tunnel, the radius of curvature is entered as 0.8m to 4m and the starting position of the path. At the same time, a high-definition camera is started to scan the work surface. The terminal automatically compares the scan results with the entered parameters. If the deviation is ≤3%, the path is confirmed to be valid; otherwise, the operator is prompted to re-enter the information. Select the installation direction according to the pre-planned path type: For convex curved surfaces, select upright installation, attach the connecting side plate 2 to the bottom of the machine body 1, align the positioning hole, screw in the bolt, and insert the quick-locking pin; for concave curved surfaces, select reverse installation, rotate the connecting side plate 2 180°, and repeat the above installation steps. After installation, rotate the adjustment knob of the curved surface curvature sensor 15 to make the detection direction consistent with the path direction.

[0034] The above are merely embodiments of this utility model. Commonly known structures and characteristics are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are aware of all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, based on the guidance provided in this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of this utility model. These should also be considered within the scope of protection of this utility model, and will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A variable-direction wheel assembly for traveling on curved surfaces, characterized in that, The system includes a machine body, with connecting side plates fixed to both sides of its bottom. A wheel assembly fixing side plate is fixedly connected to the end of each connecting side plate away from the machine body. A driving wheel and a driven wheel are rotatably connected to the wheel assembly fixing side plate. An arc-shaped sliding groove is provided on the wheel assembly fixing side plate corresponding to the driven wheel. Sliding blocks are fixed to both ends of the driven wheel's axle, and these sliding blocks are slidably engaged with the arc-shaped sliding groove. A rotation drive device is also fixed to the wheel assembly fixing side plate. A rotating rod is connected to the output end of the rotation drive device, and the end of the rotating rod away from the rotation drive device is hinged to the driven wheel's axle. A drive motor is located on one side of the driving wheel, and the output shaft of the drive motor is drively connected to the driving wheel's axle. An elastic track is fitted between the driving wheel and the driven wheel.

2. The variable-direction wheel assembly for traveling on curved surfaces according to claim 1, characterized in that, The sliding groove is an arc-shaped sliding groove, which is connected to the driven wheel.

3. The variable-direction wheel assembly for traveling on curved surfaces according to claim 1, characterized in that, The rotation drive device is located at the center of the sliding groove, and the rotation drive device has a structure that can rotate in both directions.

4. The variable-direction wheel assembly for traveling on curved surfaces according to claim 1, characterized in that, A curvature sensor is provided on one side of the fixed side plate of the wheel set. This curvature sensor is a four-core fiber optic curvature sensor, and its detection direction is consistent with the walking direction of the wheel set.

5. The variable-direction wheel assembly for traveling on curved surfaces according to claim 1, characterized in that, A curved surface contact pressure monitoring sensor is provided on the inner side of the track. The curved surface contact pressure monitoring sensor is a thin film pressure sensor and is arranged at intervals of 20-30mm along the length of the track.

6. The variable-direction wheel assembly for traveling on curved surfaces according to claim 1, characterized in that, Pressure sensors are provided on the inner sides of the driving wheel and the driven wheel. These pressure sensors are miniature piezoresistive pressure sensors, and 3 to 4 of them are evenly arranged along the circumference of the gears of the driving wheel and the driven wheel.

7. The variable-direction wheel assembly for traveling on curved surfaces according to claim 1, characterized in that, The height displacement of the driven wheel as it slides in the sliding groove is less than the diameter radius of the driven wheel.

8. The variable-direction wheel assembly for traveling on curved surfaces according to claim 1, characterized in that, The diameter of the driving wheel is twice the diameter of the driven wheel.

9. The variable-direction wheel assembly for traveling on curved surfaces according to claim 1, characterized in that, The machine body is equipped with a microprocessor, which is electrically connected to a surface curvature sensor, a surface fitting pressure monitoring sensor, a pressure sensor, and a rotation drive device. The microprocessor is used to control the rotation of the rotation drive device based on sensor data, thereby controlling the position of the driven wheel in the sliding groove.

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