Aircraft surface fatigue crack inspection device based on unmanned aerial vehicle vision

Abstract

The invention relates to the technical field of fatigue monitoring, in particular to an unmanned aerial vehicle vision-based aircraft surface fatigue crack inspection device, which comprises an unmanned aerial vehicle, an image acquisition module, a clamping structure, an air bag, a flow guide box, an air pump and an air flow triggering assembly, and is characterized in that the image acquisition module is arranged on the unmanned aerial vehicle, and the clamping structure is arranged at the bottom of the unmanned aerial vehicle; the air bag is arranged on the side, attached to the fuselage, of the clamping structure. The flow guide box is arranged at the top of a fuselage of the unmanned aerial vehicle, and an airflow inlet and an airflow outlet are formed in the flow guide box; the air pump is arranged in the flow guide box, the output end of the air pump communicates with the air bag, and the airflow triggering assembly is used for triggering a power source of the unmanned aerial vehicle to be communicated with the air pump in the flow guide box under the airflow effect to inflate the air bag when the aircraft taxies and takes off. According to the method, the fatigue cracks of the fuselage of the aircraft are visually monitored in the taxiing stage before the aircraft takes off, the monitored unmanned aerial vehicle is ejected when the aircraft takes off, and flight of the aircraft is not affected.

Description

Technical Field

[0001] This invention relates to the field of fatigue monitoring technology, specifically to a device for inspecting fatigue cracks on aircraft surfaces based on UAV vision. Background Technology

[0002] During repeated takeoffs, landings, and flights, an aircraft's structure is continuously subjected to alternating loads. This can easily lead to fatigue cracks in stress concentration areas such as rivet holes and joints in critical components like the wings and fuselage. If these cracks are not detected in time, they may continue to propagate, ultimately endangering flight safety and causing serious consequences. Therefore, regular and effective fatigue crack inspections of aircraft surfaces, especially critical structural areas, are a crucial part of aviation maintenance and support.

[0003] Currently, fatigue crack detection on aircraft surfaces mainly relies on traditional methods. Firstly, there is manual visual inspection, where maintenance personnel use aerial work platforms, scaffolding, or other equipment to approach the aircraft surface, or directly observe the fuselage from the ground. This method is not only inefficient, but the inspection quality is also greatly affected by the experience and condition of the personnel. Furthermore, it poses significant challenges and safety hazards for areas located at high altitudes, such as the upper surface of the wing, which are difficult to access. Secondly, although existing technologies have developed solutions using ground robots or large, fixed automated equipment for scanning, these devices are often cumbersome to deploy, lack mobility, and cannot quickly adapt to the inspection needs of different aircraft models and locations. They are also difficult to complete rapid inspections during the downtime of daily aircraft operations.

[0004] In addition, there are technological concepts for using drones for inspection, typically involving remote control by a pilot or autonomous flight by the drone to collect images close to the aircraft surface. However, this method has significant limitations: First, operating drones in confined spaces such as hangars carries the risk of collision with the aircraft itself; second, the airflow generated by the drone's rotors may stir up debris on the ground, causing secondary damage to the aircraft surface; finally, the attitude stability of conventional drones is easily affected by the environment when conducting close-range inspections, resulting in blurry images and making it difficult to conduct stable and continuous observation of specific areas.

[0005] In summary, current fatigue crack detection mainly focuses on monitoring aircraft when they are stationary. This is because fatigue cracks are primarily caused by repeated takeoffs and landings. During the takeoff roll, the fuselage experiences gradually increasing aerodynamic loads. Therefore, how to detect fatigue cracks during this period is a crucial issue that needs to be addressed.

[0006] Therefore, there is a need to provide an aircraft surface fatigue crack inspection device based on UAV vision to solve the above problems. Summary of the Invention

[0007] This invention provides a device for inspecting fatigue cracks on aircraft surfaces based on UAV vision, in order to solve existing problems.

[0008] The present invention provides a device for inspecting aircraft surface fatigue cracks based on UAV vision, which adopts the following technical solution, including: Drones; An image acquisition module, installed on the drone, is used to acquire images of the aircraft's surface; A snap-fit ​​structure, located at the bottom of the drone, is used to snap onto the aircraft fuselage; The airbag is located on one side of the snap-fit ​​structure that fits into the body; The airflow deflector is located on the top of the drone's fuselage, and has an airflow inlet and an airflow outlet along the direction of the drone's fuselage. An air pump is installed inside the air guide box, and its output end is connected to the airbag; And an airflow triggering component, which is used to trigger the power supply of the drone and the air pump in the airflow box to inflate the airbag when the aircraft is taking off.

[0009] A further technical solution of the present invention is that the image acquisition module includes: The main camera is located at the head of the drone; It also includes multiple secondary cameras, which are connected to both sides of the drone's tail via a gimbal.

[0010] A further technical solution of the present invention is that air guide fans are symmetrically arranged on both sides of the fuselage of the drone, and the axis of the air guide fans is parallel to the axis of the fuselage of the drone.

[0011] A further technical solution of the present invention is that a drive motor is provided on the fuselage of the drone on both sides of the air guide fan, and the output shaft of the drive motor is connected to a propeller, wherein the axis of the propeller is perpendicular to the direction of the drone fuselage.

[0012] A further technical solution of the present invention is that the snap-fit ​​structure includes: an arc-shaped snap-fit ​​plate, the inner arc surface of the arc-shaped snap-fit ​​plate snapping with the fuselage of the aircraft, wherein the airbag is disposed on the inner arc surface of the arc-shaped snap-fit ​​plate.

[0013] A further technical solution of the present invention is that a connecting column is provided at the bottom of the fuselage of the drone, and the connecting column is connected to the outer arc surface of the arc-shaped card plate.

[0014] A further technical solution of the present invention is that the connecting column is a hollow structure, and the cavity of the connecting column is connected to the inner arc surface of the arc-shaped card plate. The output end of the air pump is connected to a connecting pipe, which passes through the fuselage of the drone and the cavity of the connecting column in sequence and then connects to the airbag.

[0015] A further technical solution of the present invention is that the airflow triggering component includes: The turntable rotates within a guide box located between the airflow inlet and the airflow outlet. The duct is positioned between the turntable and the airflow outlet, and a contact ring is installed inside it; A rope is wound around a turntable. One end of the rope is equipped with a limiting structure to restrict the movement distance of the rope. The other end passes through a guide tube and a contact ring inside the guide tube and is connected to a float. The float is slidably positioned at the airflow outlet. A trigger plate is positioned on the surface of the rope. And a limiting structure, which is set on the rope to limit the rope's movement distance; When the trigger plate and the contact ring come into contact, the trigger plate, the contact ring, the air pump, and the power supply of the UAV form a closed loop.

[0016] A further technical solution of the present invention is that the limiting structure includes a limiting block, which is disposed at the end of the rope to prevent the rope from coming out of the guide tube.

[0017] A further technical solution of the present invention is that both the main camera and the secondary camera are infrared night vision cameras.

[0018] The beneficial effects of this invention are: This invention utilizes a main camera and a secondary camera, along with a gimbal, to adjust the angle and direction of the secondary camera. This facilitates the monitoring of fatigue cracks on the aircraft fuselage. Combined with a machine vision system, the results can be displayed on a screen for analysis of the fatigue crack situation. The addition of shock-absorbing blocks further reduces vibration interference to the secondary camera, improving monitoring effectiveness. Adjusting the fastening screws allows for control of the propeller's direction after ejection, thus controlling the drone's flight path. Deflector fans guide airflow during the aircraft's taxiing phase, mitigating drag as the drone increases resistance. The airflow trigger component activates an air pump under airflow, inflating the airbag and detaching the drone from the aircraft fuselage, preventing it from interfering with the aircraft during flight. This invention allows for the direct monitoring of fatigue cracks in the aircraft fuselage during the pre-takeoff taxiing phase. The monitored drone is then ejected during takeoff without affecting the aircraft's flight. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of an aircraft surface fatigue crack inspection device based on UAV vision according to the present invention. Figure 2 This is a schematic diagram of the internal structure of the flow guide box of the present invention; Figure 3 for Figure 1 A bottom view; Figure 4 This is a schematic diagram of the float after it has been blown out according to the present invention; Figure 5 This is a schematic diagram of the limiting block and the rope of the present invention.

[0021] In the diagram: 1. Main camera; 2. Fastening screw; 3. Drive motor; 4. Propeller; 5. Flow deflector; 6. Air inlet; 7. Flow deflector box; 8. Drone; 9. Shock absorber; 10. Secondary camera; 11. Universal rod; 12. Connecting column; 13. Mounting plate; 14. Clamping plate; 15. Airbag; 16. Trigger plate; 17. Conduit; 18. Rope; 19. Float; 20. Air pump. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] An embodiment of the aircraft surface fatigue crack inspection device based on UAV vision according to the present invention, such as... Figure 1As shown, the system includes: a drone 8, an image acquisition module, a snap-fit ​​structure, an airbag 15, a flow guide box 7, an air pump 20, and an airflow triggering component. The image acquisition module is mounted on the drone 8 and is used to acquire images of the drone's surface. The snap-fit ​​structure is located at the bottom of the drone 8 and is used to snap onto the drone's fuselage. The airbag 15 is located on the side of the snap-fit ​​structure that fits against the fuselage. The flow guide box 7 is located on the top of the drone 8's fuselage and has an airflow inlet 6 and an airflow outlet along the direction of the drone 8's fuselage. The air pump 20 is located inside the flow guide box 7, and the output end of the air pump 20 is connected to the airbag 15. Specifically, in this embodiment, a rubber hose is connected between the air outlet of the air pump 20 and the airbag 15 to facilitate inflation of the airbag 15. The airflow triggering component is used to trigger the drone's power supply and the air pump 20 inside the flow guide box 7 to inflate the airbag 15 when the drone is taking off.

[0024] For example, in one specific embodiment, the image acquisition module includes: a main camera 1 and multiple secondary cameras 10. The main camera 1 is located at the head of the drone 8; each secondary camera 10 is connected to both sides of the tail of the drone 8 via a universal joint 11; it should be noted that shock-absorbing blocks 9 are symmetrically installed on the side of the tail of the drone 8, and universal joints 11 are symmetrically installed on the shock-absorbing blocks 9. The secondary cameras 10 are installed at the ends of the universal joints 11. The shock-absorbing blocks 9 are made of carbon fiber composite material and have a long strip structure; the universal joints 11 are made of metal corrugated pipe.

[0025] For example, in one specific embodiment, air guide fans 5 are symmetrically arranged on both sides of the fuselage of the drone, and the axis of the air guide fan 5 is parallel to the axis of the fuselage of the drone 8.

[0026] For example, in one specific embodiment, drive motors 3 are provided on the fuselage of the drone 8 on both sides of the guide fan 5. The output shaft of the drive motor 3 is connected to a propeller 4, wherein the axis of the propeller 4 is perpendicular to the fuselage direction of the drone 8. It should be noted that, as Figure 1 As shown, a base is mounted on the drive motor 3. The base has screw holes corresponding to the fastening screws 2. By adjusting the base, the direction of the propeller 4 can be adjusted to assist the flight of the UAV 8. The flight direction of the UAV can be controlled by adjusting the base.

[0027] For example, in one specific embodiment, the snap-fit ​​structure includes: an arc-shaped snap-fit ​​plate, the inner arc surface of which snaps into the fuselage of the aircraft, wherein the airbag 15 is disposed on the inner arc surface of the arc-shaped snap-fit ​​plate, and a connecting post is disposed at the bottom of the fuselage of the UAV 8, the connecting post being connected to the outer arc surface of the arc-shaped snap-fit ​​plate; it should be noted that an mounting plate 13 is fixedly installed at the lower end of the connecting post 12 at the bottom of the UAV 8, and a snap-fit ​​plate 14 is symmetrically installed on the bottom surface of the mounting plate 13, the mounting plate 13 and the two snap-fit ​​plates 14 forming an arc-shaped snap-fit ​​plate, and the airbag 15 is installed on the bottom surface of the mounting plate 13 of the arc-shaped snap-fit ​​plate.

[0028] For example, in one specific embodiment, the connecting column is a hollow structure, and the cavity of the connecting column is connected to the inner arc surface of the arc-shaped plate. The output end of the air pump is connected to a connecting pipe, which passes through the fuselage of the UAV 8 and the cavity of the connecting column in sequence and then connects to the airbag 15.

[0029] For example, in one specific embodiment, the airflow triggering assembly includes: a turntable, a conduit 17, a rope 18, a trigger plate 16, and a limiting structure. The turntable is rotatably disposed within a guide box 7 between the airflow inlet 6 and the airflow outlet; the conduit 17 is disposed between the turntable and the airflow outlet of the guide box 7, and a contact ring is disposed within the conduit 17; Figure 4 and Figure 5 As shown, a rope 18 is wound around a turntable. One end of the rope 18 is provided with a limiting structure, and the other end of the rope 18 passes through a conduit 17 and a contact ring inside the conduit 17 and is connected to a float 19. The float 19 is slidably disposed at the airflow outlet. A trigger plate 16 is disposed on the surface of the rope 18. When the trigger plate 16 and the contact ring are in contact, the trigger plate 16, the contact ring, the air pump 20, and the power supply of the drone form a closed circuit. In this embodiment, the limiting structure includes a limiting block disposed at the end of the rope 18 to prevent the rope from detaching from the conduit 17.

[0030] It should be noted that the rope 18 is wound around the float 19 to pull it, and the float 19 pulls the rope 18. The rope 18 is made of aramid fiber, which is a high-temperature resistant rope mainly used in the aerospace field. The limiting block on the rope 18 acts as a resistance to prevent the rope 18 from completely coming out of the guide box 7. The contact piece on the rope 18 is a copper contact piece. After the contact piece contacts the copper contact ring located in the guide tube 17, the contact piece, the contact ring, the air pump 20 and the power supply of the UAV form a closed circuit. By controlling the closed circuit, the air pump 20 can be controlled to inflate the airbag 15, causing the airbag 15 to expand. The expanded airbag 15 is placed between the snap-fit ​​structure and the fuselage of the aircraft so that the UAV 20 can detach from the aircraft.

[0031] In this embodiment, both the main camera 1 and the secondary camera 10 are infrared night vision cameras.

[0032] The operation steps of this invention are as follows: Step 1: First, install the device by attaching it to the fuselage of the aircraft using an arc-shaped clip and adjusting the universal joint 11 to adjust the direction and angle of the secondary camera 10 so that the main camera 1 and the secondary camera 10 can work together to illuminate the parts of the aircraft fuselage that need to be monitored in order to monitor the fatigue cracks of the aircraft. Step 2: Adjust the fastening screw 2 to adjust the direction and angle of the propeller 4, which can control the direction of the drone 8 during its initial flight after it is launched, thus improving the safety of the drone 8 during flight. Step 3: When the aircraft is in the taxiing phase, the UAV 8 will have some resistance, but the airflow on both sides can be accelerated by the guide fan 5, which will further reduce the resistance. Step 4: During the takeoff phase, airflow enters the airflow box 7 through the airflow inlet 6, blowing the float 19 inside the airflow box 7 out through the airflow outlet. As the wind force gradually increases, the airflow acts on the float 19, causing the rope 18 to pull outward. When the part of the rope 18 with the contact piece 16 slides into the guide tube 17, the contact piece 16 contacts the contact ring inside the guide tube 17, thereby triggering the air pump 20 to inflate the airbag 15. The expansion of the airbag 15 will push the drone 8 to detach from the aircraft. Before detachment, the inspection of fatigue cracks on the aircraft fuselage is completed. This is mainly achieved through the cooperation of the main camera 1 and the secondary camera 10, combined with machine vision, to detect fatigue cracks on the aircraft surface. By inflating the airbag 15, the drone 8 is ejected, thereby reducing the impact on the aircraft during flight.

[0033] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. 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. An unmanned aerial vehicle vision-based aircraft surface fatigue crack inspection device, comprising: The drone, characterized in that it further includes: An image acquisition module, installed on the drone, is used to acquire images of the aircraft's surface; A snap-fit ​​structure, located at the bottom of the drone, is used to snap onto the aircraft fuselage; The airbag is located on one side of the snap-fit ​​structure that fits into the body; The airflow deflector is located on the top of the drone's fuselage, and has an airflow inlet and an airflow outlet along the direction of the drone's fuselage. An air pump is installed inside the air guide box, and its output end is connected to the airbag; And an airflow triggering component, which is used to trigger the power supply of the drone and the air pump in the airflow box to inflate the airbag when the aircraft is taking off.

2. The apparatus for inspecting fatigue cracks on the surface of an aircraft based on the vision of a UAV according to claim 1, characterized in that, The image acquisition module includes: The main camera is located at the head of the drone; It also includes multiple secondary cameras, which are connected to both sides of the drone's tail via a gimbal.

3. The apparatus for inspecting fatigue cracks on the surface of an aircraft based on the vision of a UAV according to claim 1, characterized in that, The drone has symmetrical air deflectors on both sides of its fuselage, and the axis of the air deflectors is parallel to the axis of the drone's fuselage.

4. The aircraft surface fatigue crack inspection device based on UAV vision according to claim 3, characterized in that, Drive motors are installed on the fuselage of the drone on both sides of the air deflector. The output shaft of the drive motor is connected to a propeller, and the axis of the propeller is perpendicular to the direction of the drone fuselage.

5. The aircraft surface fatigue crack inspection device based on UAV vision according to claim 1, characterized in that, The snap-fit ​​structure includes: an arc-shaped snap-fit ​​plate, the inner arc surface of which snaps into the fuselage of the aircraft, wherein the airbag is located on the inner arc surface of the arc-shaped snap-fit ​​plate.

6. The aircraft surface fatigue crack inspection device based on UAV vision according to claim 5, characterized in that, The bottom of the drone's fuselage is equipped with a connecting column, which is connected to the outer arc surface of the arc-shaped card plate.

7. The aircraft surface fatigue crack inspection device based on UAV vision according to claim 6, characterized in that, The connecting column is a hollow structure, and the cavity of the connecting column is connected to the inner arc surface of the arc-shaped plate. The output end of the air pump is connected to a connecting pipe, which passes through the fuselage of the drone and the cavity of the connecting column in sequence before connecting to the airbag.

8. The aircraft surface fatigue crack inspection device based on UAV vision according to claim 1, characterized in that, The airflow triggering component includes: The turntable rotates within a guide box located between the airflow inlet and the airflow outlet. The duct is positioned between the turntable and the airflow outlet, and a contact ring is installed inside it; A rope is wound around a turntable. One end of the rope is equipped with a limiting structure to restrict the movement distance of the rope. The other end passes through a guide tube and a contact ring inside the guide tube and is connected to a float. The float is slidably positioned at the airflow outlet. And a trigger plate, which is set on the surface of the rope; When the trigger plate and the contact ring come into contact, the trigger plate, the contact ring, the air pump, and the power supply of the UAV form a closed loop.

9. The aircraft surface fatigue crack inspection device based on UAV vision according to claim 8, characterized in that, The limiting structure includes a limiting block, which is located at the end of the rope to prevent the rope from coming off the guide tube.

10. The aircraft surface fatigue crack inspection device based on UAV vision according to claim 2, characterized in that, Both the main camera and the secondary camera are infrared night vision cameras.

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