Non-destructive testing apparatus for implementing a close-up observation scan of a bridge

Abstract

The present application belongs to the technical field of bridge detection, and particularly relates to a nondestructive testing equipment for realizing close observation scanning of a bridge, comprising a UAV, wherein the UAV comprises a fuselage, a plurality of wings fixed on the UAV, and a propeller arranged on the wings, and characterized in that: a wall-adhering shooting assembly is arranged on the top of the fuselage, the wall-adhering shooting assembly comprises a support column, an overhead camera arranged on the top surface of the support column, and a plurality of fixing columns, the top end of the fixing column is higher than the overhead camera, and a universal ball is arranged on the top end of the fixing column; the bridge on the top of the UAV can be detected, when the universal ball on the top end of the fixing column is in contact with the top building, the distance between the UAV and the top building will not cause the shaking of the camera imaging system due to the reflection airflow of the UAV, and the detection result will be more accurate.

Description

Technical Field

[0001] This invention belongs to the field of bridge inspection technology, specifically relating to a non-destructive testing device for close-up observation and scanning of bridges. Background Technology

[0002] Bridges play a crucial role in road traffic, and their health directly affects the safety of people's lives and property. To address the limitations of existing bridge inspection vehicles, such as their unsuitability for various bridge types, severe traffic obstruction, and high operating costs, methods utilizing drone-borne equipment for bridge inspection have emerged. Drone technology can assess the health of bridges, helping transportation managers quickly grasp information on the repair or maintenance needs of major bridges in the city.

[0003] In the field of bridge defect identification and detection using unmanned aerial vehicles (UAVs), Xu Chao's team (Xu Chao. Experimental Study on Stable Imaging and Safe Flight Distance for Bridge Defect Identification Based on UAVs [D]. Hunan University of Science and Technology) modified the power and appearance design of the EHM-6V hexacopter UAV. They mounted a Sony lens on top of the UAV for detecting bridges above it, and a three-point laser rangefinder, triggered synchronously with the shutter, below the UAV for detecting the distance to objects on its sides. During close-range detection experiments on two models—a simply supported bridge and an arched bridge—built in a wind tunnel laboratory, the wind tunnel effectively simulated the wind field of the real external environment. However, several factors affected the detection results during UAV flight: First, the rotation of the propellers generates vertical airflow, which has an aerodynamic effect on the fuselage, causing vibrations in the imaging system and thus affecting the detection quality and preventing accurate data acquisition. Second, the wind field in the natural environment and the reflected airflow between the UAV and buildings during flight also cause vibrations in the fuselage, affecting the detection quality. Third, when inspecting the bottom of a bridge, the camera mounted on the top of the drone cannot maintain an effective safe distance from the bottom of the bridge, which can easily cause the lens to collide with the bottom of the bridge, resulting in damage to both the lens and the drone.

[0004] Currently, drones used for bridge inspection all face challenges during close-range inspections, including flight safety issues, aerodynamic effects caused by propeller rotation, and the inability of onboard imaging systems to safely and stably approach the object being inspected. These factors severely restrict the development of drone-based bridge inspection systems. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a non-destructive testing device for close-range observation and scanning of bridges. It can detect bridges on the top of a drone and reduce aerodynamic interference when the drone is close to the measurement site, making image acquisition more stable, detection more accurate and convenient. When the drone is close to the measurement site, the wall-mounted shooting component can effectively control the distance between the drone and the building on top, while avoiding damage to the upper-mounted camera lens.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A non-destructive testing device for close-range observation and scanning of bridges includes a drone. The drone includes a fuselage, several wings fixed to the drone, and propellers mounted on the wings. A wall-mounted imaging component is mounted on the top of the fuselage. The wall-mounted imaging component includes a support column, an upper-mounted camera mounted on the top surface of the support column, and several fixed columns. The top of each fixed column is higher than the upper-mounted camera, and a omnidirectional ball is mounted on the top of each fixed column. The omnidirectional ball moves along the bottom surface of the wall during measurement. The support column and fixed columns have a certain height to avoid reflected airflow from the drone and to avoid damage to the lens of the upper-mounted camera.

[0008] Furthermore, the fixed post surrounds the outer ring of the upper camera to prevent damage to the side of the upper camera.

[0009] Furthermore, the wall-mounted shooting assembly also includes a transition seat, a joint, and a two-axis gimbal disposed within the transition seat and the joint. The transition seat and the two-axis gimbal are fixed to the top surface of the fuselage. The support column is connected to the transition seat via the joint. The upper part of the two-axis gimbal is connected to the inner wall of the support column, allowing the support column to rotate horizontally and swing vertically relative to the transition seat. A control board is also provided inside the transition seat. The control board is equipped with a gyroscope module or can acquire the deflection angle of the drone and calculate the correction angle of the two-axis gimbal based on the deflection angle of the drone. The control board controls the movement of the two-axis gimbal to drive the support column to rotate by the corresponding correction angle, so that the support column always remains vertical.

[0010] Furthermore, the transition seat is higher than the drone propeller.

[0011] Furthermore, the two-axis gimbal includes a first bracket fixed to the top surface of the UAV, a first servo mounted on the first bracket, a second bracket fixedly connected to the output shaft of the first servo, a second servo fixed to the second bracket, a U-shaped bracket fixedly connected to the output shaft of the second servo, and a third bracket fixedly connected to the U-shaped bracket. The end of the U-shaped bracket away from the output shaft of the second servo is rotatably connected to the second bracket, and both sides of the third bracket are fixed to the inner wall of the support column. The output shaft directions of the first servo and the second servo are vertical and horizontal, respectively.

[0012] Furthermore, the support column includes an upper support column and a lower support column spaced apart, and a sponge support section connecting the upper support column and the lower support column.

[0013] Furthermore, the distance between the omnidirectional ball and the top surface of the fuselage is 18±2cm.

[0014] Furthermore, the support column is cylindrical in shape.

[0015] Furthermore, the ratio of the diameter of the support column to the length of the fuselage is 1:2.5.

[0016] Furthermore, the drone also includes a lower-mounted camera and support legs disposed below the fuselage, the support legs being arranged around the lower-mounted camera.

[0017] The beneficial effects of this invention are:

[0018] This invention can detect bridges on top of drones and reduces aerodynamic interference when drones approach for measurement, making the detection more accurate and convenient. Moreover, when drones approach for measurement, the fixed column structure can effectively control the distance between the drone and the top building, avoiding damage to the top-mounted camera lens.

[0019] Furthermore, when the omnidirectional ball at the top of the fixed column contacts the building, the distance between the drone and the building will not cause the camera imaging system to shake due to the reflected airflow from the drone, resulting in more accurate detection results. As the drone moves forward, the omnidirectional ball will also move along the building, maintaining a consistent shooting distance for the top-mounted camera. The gaps between the fixed columns also provide the camera lens with a wider field of view, improving the range and efficiency of camera imaging detection.

[0020] This invention can help transportation managers quickly grasp information on the need for repair or maintenance of major bridges in the city, and can also overcome the flight safety problems of ordinary drones in close-range inspection, the aerodynamic effects caused by propeller rotation, and the stability of the onboard imaging system. Attached Figure Description

[0021] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. Wherein:

[0022] Figure 1 This is a three-dimensional structural diagram of an embodiment of the present invention.

[0023] Figure 2 This is a schematic diagram of the main structure of an embodiment of the present invention.

[0024] Figure 3 This is a top view of the structure according to an embodiment of the present invention.

[0025] Figure 4 This is a schematic diagram of the structure of the drone when it is tilted forward according to an embodiment of the present invention.

[0026] Figure 5 This is a schematic diagram of the installation of a two-axis gimbal according to an embodiment of the present invention.

[0027] Figure 6 This is a schematic diagram showing the state of the sponge support section before and after being compressed, according to an embodiment of the present invention.

[0028] In the diagram, 1-fuselage, 2-support leg, 3-lower camera, 4-transition seat, 5-joint, 51-retaining ring, 6-support column, 61-upper support column, 62-lower support column, 7-fixed column, 8-omnidirectional ball, 9-upper camera, 10-first bracket, 11-first servo motor, 12-second bracket, 13-second servo motor, 14-U-shaped bracket, 15-third bracket, 16-sponge support section, 17-sponge mounting plate, 18-sponge mounting bracket, 19-top mounting bracket, 20-top plate. Detailed Implementation

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art are within the scope of protection of the present invention.

[0030] In the description of this invention, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and do not require the invention to be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. The terms "connected" and "linked" used in this invention should be interpreted broadly. For example, they can refer to a fixed connection or a detachable connection; they can refer to a direct connection or an indirect connection through intermediate components. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0031] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0032] like Figures 1 to 5 As shown, a non-destructive testing device for close-range observation and scanning of bridges includes a drone. The drone includes a fuselage 1, several wings fixed to the drone, and propellers mounted on the wings. In this embodiment, a quadcopter drone is used as an example. A wall-mounted imaging component is provided on the top of the fuselage 1. The wall-mounted imaging component includes a support column 6, an upper-mounted camera 9 mounted on the top surface of the support column 6, and several fixed columns 7. All fixed columns 7 are of the same height, and the top of each fixed column 7 is higher than the upper-mounted camera 9. The fixed columns 7 control the camera's position. The distance between the drone and the building improves the stability of the imaging system; the height difference between the upper camera 9 and the top of the fixed column 7 is 2cm-5cm, which is intended to provide a certain imaging distance, and the specific range is designed according to the focal length range of the upper camera 9; the top of the fixed column 7 is provided with a universal ball 8 for the fixed column 7 to move along the bottom surface of the bridge beam; the universal ball 8 includes a ball seat and smooth balls embedded in the ball seat. A universal ball 8 of a suitable specification in the prior art can be selected and installed on the top of the fixed column 7, such as by gluing, welding or threaded connection.

[0033] Furthermore, such as Figures 1 to 4 As shown, the supporting column 6 is cylindrical in shape, and the cross-sectional shape of the fixed column 7 is circular, triangular, or trapezoidal; as Figures 1 to 2 As shown, the cross-section of the fixed column 7 is trapezoidal, with the included angle between the extensions of the two legs of this trapezoid being 90°, and the base of this trapezoid being an arc shape matching the contour of the supporting column 6; as Figure 3 , Figure 5 , Figure 6As shown, the cross-section of the fixed column 7 is circular. The cylindrical fixed column 7 reduces wind resistance during flight, reduces shaking, meets the installation requirements of the omnidirectional ball 8, and at the same time, it obstructs the field of view of the upper camera 9 less.

[0034] Furthermore, such as Figures 1 to 4 As shown, the fixed posts 7 surround the outer ring of the upper camera 9, and there are 3 to 4 fixed posts 7. The upper camera 9 is equipped with a gimbal, and its lens can rotate within a 720° range. The lens of the upper camera 9 can image and detect the bridge through the gap between two adjacent fixed posts 7 and the gap at the top of the support column 6. Preferably, the upper camera 9 is installed at the center of the multiple fixed posts 7. In a specific embodiment, the diameter of the upper camera 9 is 5cm, the four fixed posts 7 are distributed in a square, the diameter of the cylindrical fixed posts 7 is 1.5cm, the center distance between adjacent fixed posts 7 is 10.5cm, and the horizontal clearance between the upper camera 9 and the fixed posts 7 is 2cm. The fixed posts 7 provide a wide field of view for the lens of the upper camera 9, improving the detection range and efficiency.

[0035] Furthermore, such as Figures 1 to 5 As shown, the wall-mounted shooting assembly also includes a transition seat 4, a joint 5, and a two-axis gimbal disposed within the transition seat 4 and the joint 5. The transition seat 4 and the two-axis gimbal are fixed to the top surface of the body 1. Alternatively, a base plate can be provided at the bottom end of the transition seat 4, and the two-axis gimbal can be mounted on the base plate. The upper part of the transition seat 4 is open, and the joint 5 is fixedly connected or integrally connected to the lower end of the support column 6. The lower part of the joint 5 extends into the upper opening of the transition seat 4, and the joint 5 has a connection with the transition seat 4. The upper opening has a matching arc-shaped surface, and the lower end of the transition seat 4 is provided with a retaining ring 51 to limit the maximum rotation range of the support column 6; the upper part of the two-axis gimbal is connected to the inner wall of the support column 6, so that the support column 6 can rotate horizontally and swing up and down relative to the transition seat 4; for easy assembly, the top of the support column 6 is provided with a detachable top plate 20, and the fixed column 7 is fixed on the top plate 20. The top plate 20 is fixed by a top mounting bracket 19 or by a threaded mounting hole directly opened in the support column 6.

[0036] The transition seat 4 is also equipped with a control board, which is equipped with a gyroscope module or can acquire the deflection angle of the UAV and calculate the correction angle of the two-axis gimbal based on the deflection angle of the UAV. The control board controls the movement of the two-axis gimbal to drive the support column 6 to rotate the corresponding correction angle so that the support column 6 always remains vertical. The UAV battery or a battery set in the transition seat 4 can be used as the power source for the two-axis gimbal.

[0037] When the drone changes from hovering to forward motion, the different lift generated by the different rotation speeds of the four propellers will cause the fuselage 1 to tilt. At this time, the two-axis gimbal is controlled by the control board to correct the tilt and keep the support column 6 vertical. The conventional technique is to detect the tilt angle by the gyroscope and then control the tilt by the gimbal. In addition to protecting the upper camera 9, the fixed column 7 above the support column 6 has a omnidirectional ball 8 that allows the fixed column 7 and the omnidirectional ball 8 to move close to the top building when the drone is tilted and moving forward, so as to keep the imaging distance of the upper camera 9 consistent.

[0038] Furthermore, such as Figure 1 , Figure 2 , Figure 4 As shown, the height of the transition seat 4 is higher than that of the drone propeller, and the support column 6 will not interfere with the movement of the drone propeller no matter how it rotates.

[0039] Furthermore, such as Figure 5 As shown, the two-axis gimbal includes a first bracket 10 fixed to the top surface of the UAV, a first servo motor 11 mounted on the first bracket 10, a second bracket 12 fixedly connected to the output shaft of the first servo motor 11, a second servo motor 13 fixedly mounted on the second bracket 12, a U-shaped bracket 14 fixedly connected to the output shaft of the second servo motor 13, and a third bracket 15 fixedly connected to the U-shaped bracket 14. One end of the U-shaped bracket 14 away from the output shaft of the second servo motor 13 is rotatably connected to the second bracket 12. The two sides of the third bracket 15 are fixed to the inner wall of the support column 6. The output shaft of the first servo motor 11 is vertical, and the center of gravity of the UAV coincides with the axis of the output shaft of the first servo motor 11. The axis of the output shaft of the second servo motor 13 is horizontal. Thus, the two-axis gimbal can drive the support column 6 to rotate in both the horizontal and vertical directions, and correct the support column 6 according to the instructions of the control board to keep it always in a vertical state.

[0040] Furthermore, such as Figure 5 , Figure 6As shown, due to the rapid movements of the UAV during attitude adjustment, the control board's control of the two-axis gimbal for correction may be slow, especially at curves in the flight path. This causes the fixed column 7 to detach from the bridge bottom, resulting in fluctuations in the measurement distance of the upper-mounted camera 9 and affecting the imaging effect. In this embodiment, a sponge support section 16 is set inside the support column 6 to reduce the impact of the slowness of the support column 6 during active correction on the upper-mounted camera 9. The support column 6 includes an upper support column 61 and a lower support column 62 spaced apart, and a sponge support section 16 connecting the upper support column 61 and the lower support column 62. 6; The sponge support section 16 is made of elastic materials such as sponge, foam, rubber, and latex. The sponge support section 16 is annular, with an outer diameter consistent with the support column 6. The thickness of the sponge support section 16 is 6mm-20mm, and the height of the sponge support section 16 is 10mm-25mm. Sponge mounting plates 17 are attached to the upper and lower sides of the sponge support section 16. A sponge mounting frame 18 is provided at the relative position of the upper support column 61 and the lower support column 62. The sponge mounting plates 17 are attached, riveted, bolted, or welded to the sponge mounting frame 18.

[0041] Due to the presence of the sponge support section 16, when the lower support column 62 has not had time to adjust to a vertical position under the action of the two-axis gimbal, the upper support column 61, thanks to the omnidirectional ball 8 located at its top, continues to move along the bottom surface of the bridge. Therefore, the upper support column 61 can still maintain a perpendicular state to the bottom surface of the bridge under the action of three to four omnidirectional balls 8 and the fixed column 7. That is, the sponge support section 16 acts as a buffer to reduce the position fluctuation of the upper camera 9 during the correction process of the support column 6. When the drone is in a forward state, depending on the tilt of the body 1, it can also rely solely on the small-angle buffering effect of the sponge support section 16 without relying on the adjustment action of the two-axis gimbal to keep all the omnidirectional balls 8 close to the bottom surface of the bridge, keeping the horizontal height of the upper camera unchanged. The two-axis gimbal is only used to maintain the position of the upper camera 9 when the tilt of the body 1 exceeds a certain angle. Moreover, the sponge support section 16 has a certain degree of support and will not cause the fixed column 7 and the upper camera to shake without the action of external force.

[0042] Furthermore, the distance between the omnidirectional ball 8 and the top surface of the body 1 is 18±2cm. When moving close to the bottom of the bridge at this distance, the aerodynamic interference will hardly affect the imaging system of the upper camera 9, thus improving the stability of the imaging system.

[0043] Furthermore, the support column 6 is cylindrical in shape to prevent the propeller from colliding with the support column 6.

[0044] Furthermore, the ratio of the diameter of the support column 6 to the length of the fuselage 1 is 1:2.5; the preferred design of the fuselage 1 / UAV size ratio overcomes the vibration of the fuselage 1 caused by the wind field of the natural environment and the reflected airflow between the UAV and the building during flight.

[0045] Furthermore, such as Figure 1 , Figure 2 , Figure 4 As shown, the drone also includes a lower camera 3 and support legs 2 located below the fuselage 1. The support legs 2 are arranged around the lower camera 3. The lower camera 3 is equipped with a gimbal and a lens that can rotate 720° to detect the buildings around the fuselage 1. There is a certain distance between the lower camera 3 and the support legs 2. This distance is to allow the camera to rotate 720° in the lower space to detect the buildings at the lower part of the drone fuselage 1. When the drone lands, the support legs 2 can cushion the impact on the upper camera 9 and the lower camera 3. Generally, there are 4 support legs 2. The lower ends of two opposite support legs 2 can be connected by a horizontal leg.

[0046] The main difference between the device of this invention and ordinary drones is that it is equipped with a controllable distance, stable imaging, and continuous observation wall-mounted shooting component on top of the drone. It can effectively control the distance between the drone and the building above, effectively reduce the interference of aerodynamic effects, and avoid the shaking of the imaging systems of the upper camera 9 and lower camera 3 when the drone approaches the building, thereby improving the safety of the drone when it approaches the building and the stability of the upper camera 9. The two-axis gimbal and the support column 6 equipped with the sponge support section 16 on the drone can also keep the support column 6 and the upper camera 9 in a vertical state at all times, improving the stability of the camera imaging system. Moreover, through the combination of the support column 6, the fixed column 7 and the omnidirectional ball 8, the device can move along the bottom surface of the bridge beam, enabling the drone to achieve stable identification and detection during its forward movement.

[0047] This invention utilizes two cameras, one above and one below, to identify and detect bridge defects. Compared to conventional detection methods using a drone with a bottom-mounted gimbal camera, our invention can detect bridges on the top of the drone. It also reduces aerodynamic interference when the drone is close to the building for measurement, making the detection more accurate and convenient. Furthermore, when the drone is close to the building for measurement, the wall-mounted shooting component structure can effectively control the distance between the drone and the building, avoiding damage to the camera lens. It can also overcome the vibration of the drone caused by wind fields in the natural environment and the reflected airflow between the drone and the building during flight.

[0048] It is understood that the above description is merely exemplary and the embodiments of this application are not intended to limit the scope of the invention. The above description is only a preferred embodiment of the present invention and is not intended to limit the invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are within the scope of protection of the pending claims of the present invention.

Claims

1. A non-destructive testing device for close-range observation and scanning of bridges, comprising a drone, the drone comprising a fuselage (1) and a plurality of wings fixed to the drone and propellers disposed on the wings, characterized in that: The top of the body (1) is provided with a wall-mounted shooting component. The wall-mounted shooting component includes a support column (6), an upper-mounted camera (9) and several fixed columns (7) on the top surface of the support column (6). The top of the fixed column (7) is higher than the upper-mounted camera (9). The top of the fixed column (7) is provided with a omnidirectional ball (8). The wall-mounted shooting assembly also includes a transition seat (4), a joint (5), and a two-axis gimbal set in the transition seat (4) and the joint (5). The transition seat (4) and the two-axis gimbal are fixed on the top surface of the fuselage (1). The support column (6) is connected to the transition seat (4) through the joint (5). The upper part of the two-axis gimbal is connected to the inner wall of the support column (6), so that the support column (6) can rotate horizontally and swing up and down relative to the transition seat (4). A control board is also provided in the transition seat (4). The control board is equipped with a gyroscope module. The control board obtains the deflection angle of the UAV and calculates the correction angle of the two-axis gimbal based on the deflection angle of the UAV. It controls the movement of the two-axis gimbal to drive the support column (6) to rotate the corresponding correction angle so that the support column (6) always remains vertical. The support column (6) includes an upper support column (61) and a lower support column (62) spaced apart, and a sponge support section (16) connecting the upper support column (61) and the lower support column (62).

2. The non-destructive testing equipment for close-range observation and scanning of bridges according to claim 1, characterized in that: The fixed column (7) surrounds the outer ring of the upper camera (9).

3. The non-destructive testing equipment for close-range observation and scanning of bridges according to claim 1, characterized in that: The transition seat (4) is higher than the drone propeller.

4. The non-destructive testing equipment for close-range observation and scanning of bridges according to claim 1, characterized in that: The two-axis gimbal includes a first bracket (10) fixed on the top surface of the UAV, a first servo motor (11) mounted on the first bracket (10), a second bracket (12) fixedly connected to the output shaft of the first servo motor (11), a second servo motor (13) fixed on the second bracket (12), a U-shaped bracket (14) fixedly connected to the output shaft of the second servo motor (13), and a third bracket (15) fixedly connected to the U-shaped bracket (14). The end of the U-shaped bracket (14) away from the output shaft of the second servo motor (13) is rotatably connected to the second bracket (12), and the two sides of the third bracket (15) are fixed to the inner wall of the support column (6). The output shaft directions of the first servo motor (11) and the second servo motor (13) are vertical and horizontal, respectively.

5. The non-destructive testing equipment for close-range observation and scanning of bridges according to claim 1, characterized in that: The distance between the omnidirectional ball (8) and the top surface of the fuselage (1) is 18±2cm.

6. The non-destructive testing equipment for close-range observation and scanning of bridges according to claim 1, characterized in that: The support column (6) is cylindrical in shape.

7. The non-destructive testing equipment for close-range observation and scanning of bridges according to claim 5, characterized in that: The ratio of the diameter of the support column (6) to the length of the fuselage (1) is 1:2.

5.

8. The non-destructive testing equipment for close-range observation and scanning of bridges according to claim 1, characterized in that: The drone also includes a lower-mounted camera (3) located below the fuselage (1) and a support leg (2), the support leg (2) being arranged around the lower-mounted camera (3).

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