KR20240055535A - Concrete structure inspection device using unmanned aerial vehicle - Google Patents

Abstract

The present invention relates to a concrete structure inspection device using an unmanned aerial vehicle that can inspect defects using a striking method while flying close to a concrete structure such as a bridge.
The concrete structure inspection device using an unmanned aerial vehicle according to the present invention includes a drone that can fly under control and move to an inspection location for the structure to be inspected, and is mounted on the drone to inspect the structure by striking, and strikes. It includes a striking unit that fires a ball and strikes the surface of the structure with the striking ball that flies in a free trajectory due to inertia.

Description

Concrete structure inspection device using unmanned aerial vehicle}

The present invention relates to a concrete structure inspection device using an unmanned aerial vehicle, and more specifically, to a concrete structure inspection device using an unmanned aerial vehicle that can inspect defects using a striking method while flying close to a concrete structure such as a bridge.

Large structures and facilities built in the process of developing into an industrial society suffer structural damage due to defects in the design and construction process or various factors that were not considered at the time of design, and as the period of use of these structures passes, they gradually deteriorate. Its safety is greatly threatened. For example, in the case of structures with severe structural damage, there are frequent cases where the service life is shortened to a level that falls far short of the design service life planned at the time of design.

Accordingly, efforts are urgently needed to ensure the long-term safety and operability of building structures. In particular, large structures such as buildings, bridges, dams, etc. are continuously exposed to various operating loads, shocks from external objects, earthquakes, wind loads, wave loads, corrosion, etc., so the problem of ensuring the safety of structures from these is an economic and social issue. It is becoming an issue of great interest. In order to accurately diagnose the safety of these large structures, monitoring of structural behavior through appropriate experimental measurements, technology to dynamically analyze structural damage, and diagnostic technology through analysis to model structural damage are required.

Technologies used to detect damage to these large structures include material non-destructive testing methods, positive displacement measurement methods, and vibration characteristic measurement methods. For example, among these, the method of estimating damage to a structure using positive displacement measurement and vibration characteristics is usually called System Identification (SID). This structural identification technique (SID) is a method of estimating structural characteristics by measuring the behavior of the structural system and modeling it through structural analysis.

As mentioned above, non-destructive testing technology for evaluating abnormal behavior of structures is a cutting-edge technology that is highly utilized across industries such as machinery, aviation, shipbuilding, and construction. In particular, in the case of large infrastructure facilities such as ultra-long bridges and high-rise buildings, abnormal behavior causes damage, which in turn causes enormous economic damage and serious human casualties, so the operation of flawless behavior evaluation is essential.

Accordingly, periodic safety inspections are being conducted on major social infrastructure facilities, but they are mainly limited to visual inspections of accessible points by inspectors. In addition, there is a lack of manpower and resources required for inspection and inspection of inaccessible facilities. The reality is that the inspection cycle is limited due to inspection difficulties. In addition, in order to complement the problems of the non-destructive diagnosis method according to the above-mentioned conventional technology, there is a need to develop an algorithm technology that can detect local damage to vulnerable members early through a local measurement system.

Meanwhile, in Korea, as the number of aging special bridges increases rapidly, the number of regular inspections is also increasing, and a significant portion of these inspections are carried out visually.

In addition, research is being actively conducted to replace visual inspection by using unmanned aerial vehicles (UAVs) and image processing techniques.

In particular, technology using drones for structural inspection using the striking method is disclosed in Japanese Patent Publication No. 2018-128278. In addition, related technologies are also disclosed in Korean Patent Registration Nos. 10-2170054, 10-2170055, and 10-2250490.

The striking unit described in these prior arts is mounted on a drone, and the striking unit includes an arm having a striking tip, and an arm driving mechanism coupled to the arm. According to the arm driving mechanism, the arm performs linear reciprocating motion or rotational motion, and the striking tip can strike the surface of the structure while being spaced apart from and then approaching the surface of the structure depending on the direction of movement.

In these prior technologies, when moving a drone to an inspection position for a structure and hitting the surface of the structure, the surface of the structure must be within the range of movement of the arm by the arm driving mechanism, and to satisfy this, the drone must be moved to the surface of the structure. Because the drone must be brought close to the surface of the structure, the drone may collide with the structure due to incorrect handling or unexpected variables during the process of approaching the structure, causing damage to the drone or strike unit, or causing the drone to lose its balance or control and fall. Furthermore, there is a possibility that a secondary accident may occur due to a drone crash.

Japanese Patent Publication No. 2018-128278 (2018.08.16) Republic of Korea Patent Publication No. 10-2170054 (2020.10.26)

The present invention was created to solve the above problems, and is a concrete structure inspection using an unmanned aerial vehicle that can safely inspect safety factors such as defects or cracks in the structure through a striking sound generation method while flying close to a concrete structure such as a bridge. The purpose is to provide a device.

The concrete structure inspection device using an unmanned aerial vehicle according to the present invention includes a drone that can fly under control and move to an inspection location for the structure to be inspected, and is mounted on the drone to inspect the structure by striking. It includes a striking unit that fires a ball and strikes the surface of the structure with the striking ball that flies in a free trajectory due to inertia.

The striking unit is provided with a launch guide pipe extending in the horizontal direction and having a first end at the front end and a second end at the rear end, a ball launch port communicating with the first end, and a small-diameter through hole communicating with the second end. The striking ball is compressed by a launch tube introduced into the launch guide conduit through the ball launch port, and the striking ball provided toward the second end of the launch guide conduit and introduced into the launch guide conduit, A coil spring that fires the introduced striking ball by a restoring force, a flexible connecting string passing through the through hole with one side connected to the hitting ball, and rotatably provided at the rear of the firing tube, the through A rotary drum in which the other side of the connecting string passing through the sphere is wound, a first mode for maintaining the rotary drum in a stationary state, and a second mode for maintaining the rotary drum in a free rotational manner for firing the introduced striking ball. mode and a third mode in which the rotating drum is rotated in a winding direction for introduction of the fired hitting ball, and when the hitting ball is introduced by the third mode and the coil spring is compressed, the first mode It is desirable to include a drum drive mechanism that switches to .

The concrete structure inspection device using an unmanned aerial vehicle according to the present invention fires a striking ball and strikes the surface of the structure with the striking ball to inspect the structure by striking, thereby generating the striking sound required for inspection, so that the drone on the structure There is an advantage in that structural inspection can be safely performed from a distance where the risk of collision is relatively low or virtually non-existent.

1 is a perspective view of a concrete structure inspection device using an unmanned aerial vehicle according to an embodiment of the present invention;
FIG. 2 is a cross-sectional view showing the configuration and operation of the striking unit of the concrete structure inspection device using the unmanned aerial vehicle of FIG. 1.
FIG. 3 is a plan view showing the operation of the rotation drive unit of the concrete structure inspection device using the unmanned aerial vehicle of FIG. 1.
Figure 4 is a side view showing the inspection process by a concrete structure inspection device using an unmanned aerial vehicle according to an embodiment of the present invention.

Hereinafter, a concrete structure inspection device using an unmanned aerial vehicle according to an embodiment of the present invention will be described in detail with reference to the attached drawings. Since the present invention can be subject to various changes and can have various forms, specific embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to a specific disclosed form, and should be understood to include all changes, equivalents, and substitutes included in the spirit and technical scope of the present invention. While describing each drawing, similar reference numerals are used for similar components. In the attached drawings, the dimensions of the structures are enlarged from the actual size for clarity of the present invention.

Terms such as first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, a first component may be named a second component without departing from the scope of the present invention, and similarly, the second component may also be named a first component.

The terms used in this application are only used to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this application, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the technical field to which the present invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted in an ideal or excessively formal sense unless explicitly defined in the present application. No.

The configuration and operation of a concrete structure inspection device using an unmanned aerial vehicle according to an embodiment of the present invention are shown in FIGS. 1 to 4.

Referring to the drawings, the structure inspection device according to an embodiment of the present invention includes a drone 10, a striking unit 20, a rotation drive unit 30, and a collection unit 40.

The drone 10 is configured to be able to fly and move to the inspection location for the structure 5 to be inspected.

The strike unit 20 is mounted on the drone 10 and moves together with the drone 10 when the drone 10 flies. The striking unit 20 fires the striking ball 25 laterally in order to inspect the structure 5 using the striking method, thereby creating a striking ball (25) that flies in a free trajectory on the surface of the structure 5 by inertia. 25), the impact can be generated at the level required for the test.

The rotation drive unit 30 may change the direction in which the hitting ball 25 is launched by rotating the hitting unit 20 about a vertical axis. The collecting unit 40 collects the striking sound generated by the striking unit 20 from the striking unit 20 side. The striking sounds collected by the collecting unit 40 may be analyzed (for example, compared and analyzed with previously stored striking sounds) by the striking sound analysis unit to determine whether there is an abnormality in the structure 5.

The structure inspection device according to an embodiment of the present invention may be configured to operate in a remote control or autonomous control manner, and may use pre-programming or artificial intelligence as an example for autonomous control.

The drone 10 includes a drone body 11 and at least one propeller 12 for generating thrust necessary for flight. A propeller 12 is provided on the drone body 11. For example, three or more propellers 12 may be arranged at intervals along the upper edge area of the drone body 11. When the propeller 12 operates, the drone 10 can fly by the generated thrust.

This drone 10 may further include a support 13 used for landing. The support 13 is provided at the lower edge area of the drone body 11 and may be provided singly or in plural.

The striking unit 20 includes a firing tube 100, a coil spring 200, a ball seat 300, a connecting string 400, a rotating drum 500, and a drum driving mechanism 600.

The launch tube body 100 has a launch guide tube 110. The launch guide conduit 110 extends in one horizontal direction and has a constant length. The launch guide conduit 110 is provided inside the launch tube 100 and has a first end 111 and a second end 112 located on both sides of the longitudinal direction. The launch pipe 100 has a ball launch port 120 in communication with the first end 111 of the launch guide pipe 110, and a through hole in communication with the second end 112 of the launch guide pipe 110 ( 130). The launch tube body 100 has the ball launch port 120 side as its front end, and the through hole 130 side as its rear end. This launch pipe 100 can introduce the striking ball 25 into the launch guide pipe 110 through the ball launch port 120, and can also introduce the introduced hitting ball 25 through the ball launch port 120. It is prepared for export. For example, the launch guide pipe 110 and the ball launch port 120 may be formed so that the minimum diameter is larger than the maximum diameter of the hitting ball 25, and the ball launch port 120 has a diameter from the rear end to the front end. It can be formed into a shape that gradually expands in one direction. The through hole 130 is provided as a small diameter hole whose diameter is smaller than that of the second end 112.

The coil spring 200 is provided in the firing guide pipe 110 and disposed toward the second end 112. Accordingly, when the striking ball 25 is introduced into the launch guide pipe 110 through the ball launch port 120, the coil spring 200 may be compressed by the introduced striking ball 25. When the compressive action of the hitting ball 25 on the coil spring 200 is released, the coil spring 200 can be restored to its original state. The introduced hitting ball 25 can be sent out through the ball launch port 120 by the restoring force of the compressed coil spring 200. That is, the coil spring 200 provides a thrust resulting from a restoring force to the introduced hitting ball 25, causing the hitting ball 25 to be launched laterally. The rear end portion of the coil spring 200 facing the second end 112 may be supported by the second end 112 . Furthermore, the rear end portion of the coil spring 200 may be coupled to the second end 112 to fix the position. According to the small diameter through hole 130 compared to the second end 112, a support or coupling area for the rear end portion of the coil spring 200 can be easily secured at the second end 112.

The ball seat 300 is accommodated in the launch guide conduit 110. The ball seat 300 is disposed in front of the coil spring 200 accommodated in the launch guide conduit 110, and when the striking ball 25 is introduced into the launch guide conduit 110, the striking ball 25 and the coil spring ( 200). This ball seat 300 is provided in the launch guide conduit 110 to be able to move back and forth along the launch guide conduit 110, so that it can be moved rearward by being pushed by the striking ball 25 introduced into the launch guide conduit 110. It can be moved forward by being pushed by the restored coil spring 200.

When the ball seat 300 is pushed backwards by the hitting ball 25, the coil spring 200 is compressed. When the ball seat 300 is pushed forward by the coil spring 200, the introduced striking ball 25 is fired. This configuration of compressing the coil spring 200 and firing the hitting ball 25 using the ball seat 300 can ensure more accurate operation. The ball seat 300 is provided with a curved groove-shaped seat portion 310 that supports the hitting ball 25 in the central area of the front, and a pass hole 320 in the shape of a front and rear penetrating portion toward the center of the seat portion 310. ) is formed, and a support portion 330 that supports the tip portion of the coil spring 200 may be provided around the passage hole 320 at the rear side. The support portion 330 may be coupled to the tip portion of the coil spring 200. For reference, the ball seat 300 may have guide protrusions 350 arranged along the circumference, and the launch guide conduit 110 is paired with the guide protrusions 350 to enable reciprocating movement of the ball seat 300. Guide grooves 150 may be provided along the length of the launch guide pipe 110.

The connecting string 400 is made of a flexible material such as synthetic fiber yarn. One side of the connecting line 400 is connected to the hitting ball 25. The connecting string 400 is connected to the hitting ball 25 in this way, and the other side sequentially passes through the through hole 310 of the ball seat 300 and the empty central portion of the coil spring 200 through the through hole 130. passes.

The rotating drum 500 is rotatably provided at the rear of the launch tube 100 by a drum support structure 550. The rotary drum 500 is arranged to be rotatable about an axis in a direction perpendicular to the direction in which the launch guide pipe 110 of the launch pipe body 100 extends horizontally (i.e., the longitudinal direction of the launch guide pipe 110). It can be. The other side of the connecting string 400 that passes through the through hole 130 is wound around the rotating drum 500. The drum support structure 550 may be mounted on the rear end of the launch tube 100 while rotatably supporting the rotating drum 500. As an example, the drum support structure 550 may be provided in the form of a case.

The drum drive mechanism 600 operates in a first mode for maintaining the rotating drum 500 in a stationary state (for maintaining the coil spring 200 in a compressed state by the striking ball 25 introduced into the firing guide pipe 110). Operating mode, see (a) of FIG. 3), a second mode for maintaining the rotating drum 500 to be freely rotatable (operating mode for firing the introduced striking ball 25 with the restoring force of the coil spring 200) , and a third mode in which the rotating drum 500 is rotated in the winding direction (the launched striking ball 25 is introduced into the firing guide pipe 110, and the coil spring 200 is introduced by the introduced striking ball 25). It is configured to operate in any one mode selected from the operating mode for compression).

The drum driving mechanism 600 includes a motor 610 that provides rotational force to the rotating drum 500 to rotate the rotating drum 500 in the winding direction, a brake for stopping the rotating drum 500, And it may include a drive control means 620 that controls the operation of the motor 610 and the brake. According to this, the rotating drum 500 may be maintained in a stationary state by turning off the power of the motor 610 and activating the brake (first mode), or may be maintained in a stopped state by turning off the power of the motor 610 and activating the brake. The motor 610 may be maintained in a free rotation state (second mode) or may be maintained in a state of rotation in the winding direction by supplying power to the motor 610 and deactivating the brake (third mode). It can be directly connected to the rotating drum 500. The brake may be configured to physically restrain and release the axis of the rotating drum 500 or the motor 610. Alternatively, the brake may have a configuration that uses an inverter connected to the motor 610.

This drum driving mechanism 600 is configured to switch to the first mode or the third mode when the collecting unit 40 collects the striking sound generated by the striking ball 25 in the second mode. To this end, the drive control means 620 compares the sound collected by the collecting unit 40 in the second mode with the previously stored striking sound to determine whether the collected sound is struck by the striking ball 25, and , if the collected sound is determined to be a strike by the hitting ball 25, the motor 610 and the brake can be controlled to switch from the second mode to the first mode or the third mode.

In addition, the drum drive mechanism 600 is configured to switch to the first mode when the striking ball 25 is introduced into the launch guide pipe 110 and the coil spring 200 is compressed by the third mode. To this end, the drive control means 620 compares the value (measured value) of the load acting on the motor 610 in the third mode with the set value, and when the value of the load exceeds the set value, the hitting ball (25) ) is introduced into the firing guide pipe 110 and the coil spring 200 is determined to be compressed, and the motor 610 and the brake can be controlled to switch from the third mode to the first mode.

The rotation drive unit 30 is provided between the drone 10 and the striking unit 20, rotatably supports the striking unit 20 about a vertical axis, and provides rotational force to rotate the striking unit 20. It may include a motor that provides the striking unit 20. Specifically, the rotation drive unit 30 is provided in the lower central area of the drone body 11 and rotates the launch tube 100 or the drum support structure 550 of the striking unit 20 about a vertical axis. It is possible to support it.

The collecting unit 40 may be provided on the firing tube 100 or the drum support structure 550 of the striking unit 20. The collecting unit 40 may include a microphone. The percussion sound collected by the collection unit 40 may be separately stored for analysis by the percussion analysis unit, and a drive control means may be used to switch the drum drive mechanism 600 from the second mode to the first mode or the third mode. Can be provided at (620).

Referring to FIG. 4, the structure inspection device according to an embodiment of the present invention can inspect the structure 5 as follows.

The drone 10 is flown and the drone 10 is moved to the inspection position for the structure 5. Since the concrete structure inspection device using an unmanned aerial vehicle according to an embodiment of the present invention is configured to generate a striking sound by firing the striking ball 25, the inspection position for the structure 5 is not necessarily close to the surface of the structure 5. There is no reason it has to be location. Accordingly, a location where the risk of collision of the drone 10 with respect to the structure 5 is relatively low or virtually non-existent (however, within the effective range of the hitting ball 25) can be set as the inspection location.

Before the drone 10 arrives at the inspection location, the coil spring 200 is compressed by the striking ball 25 introduced into the launch guide pipe 110, and the rotating drum 500 is a drum drive mechanism in the first mode. It can be maintained in a stopped state by (600).

When the drone 10 arrives at the inspection location, the ball launch port 120 is set to face the surface of the structure 5. To this end, the attitude of the drone 10 can be changed by attempting a rotational flight with respect to the drone 10 that is flying in place. If other structures exist close to the drone 10, the drone 10, which is difficult to control, may accidentally collide with other structures during the attitude change process. In this case, instead of significantly changing the flight state of the sensitive drone 10, the striking unit 20 is rotated about the vertical axis by the rotation drive unit 30 so that the ball launcher 120 is connected to the structure 5. It can be set to face the surface.

Next, the drum drive mechanism 600 is switched from the first mode to the second mode. Then, the rotating drum 500 is maintained in a free rotatable state and the coil spring 200 is restored, so that the ball seat 300 is rapidly advanced and the striking ball 25 is moved laterally toward the surface of the structure 5. (see (a) in FIG. 5)) the freely rotatable rotating drum 500 is rotated in the unwinding direction by the connecting string 400, and the launched hitting ball 25 is launched in a free trajectory. While flying, it strikes the surface of the structure 5 to generate striking noise, and the collecting unit 40 collects the generated striking noise.

When the hitting by the striking ball 25 is collected, the drum driving mechanism 600 switches from the second mode to the first mode or the third mode to prevent the connecting string 400 from continuing to be released from the rotating drum 500.

Next, if the drum driving mechanism 600 is in the first mode, it switches to the third mode, and if it is in the third mode, the third mode is maintained as is. Then, the rotating drum 500 is rotated in the winding direction so that the connecting string 400 is wound around the rotating drum 500, and the fired hitting ball 25 is introduced into the firing guide pipe 110, so that the ball seat 300 moves backward. And the coil spring 200 is compressed by the ball seat 300 moving backwards. When the compression of the coil spring 200 by the hitting ball 25 is completed, the drum driving mechanism 600 switches from the third mode to the first mode, and the connecting string 400 is broken or the drum driving mechanism 600 is damaged. Prevent damage from overload, etc.

Once the collection unit 40 collects the strike by the striking ball 25, the drone 10 can be moved to the next inspection location for the structure 5. The process of switching the drum drive mechanism 600 from the third mode to the first mode to retrieve the launched striking ball 25 will be performed during the process of moving the drone 10 to the next inspection position for the structure 5. It may be possible.

The description of the presented embodiments is provided to enable any person skilled in the art to use or practice the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the scope of the invention. Thus, the present invention is not limited to the embodiments presented herein, but is to be construed in the broadest scope consistent with the principles and novel features presented herein.

5: Structure 10: Drone
20: striking unit 25: striking ball
40: Collection unit
100: Launch pipe 110: Launch guide pipe
200: coil spring
300: Ball seat
400: connection line
500: rotating drum
600: Drum driving mechanism

Claims (3)

A drone that can fly under control and move to the inspection location for the structure to be inspected;
In order to inspect the structure by striking, it is mounted on the drone and includes a striking unit that fires a striking ball and strikes the surface of the structure with the striking ball flying in a free trajectory by inertia.
Concrete structure inspection device using an unmanned aerial vehicle. According to clause 1,
The striking unit is provided with a launch guide pipe extending in the horizontal direction and having a first end at the front end and a second end at the rear end, a ball launch port in communication with the first end, and a small-diameter through hole in communication with the second end. And a launch pipe body through which the hitting ball is introduced into the launch guide pipe through the ball launch port;
a coil spring provided to the second end in the launch guide conduit, compressed by the striking ball introduced into the launch guide conduit, and firing the introduced striking ball by a restoring force;
a flexible connecting string passing through the through hole with one end connected to the hitting ball;
a rotating drum rotatably provided at the rear of the firing tube and wound around the other side of the connecting string that has passed through the through hole;
A first mode of maintaining the rotating drum in a stationary state, a second mode of maintaining the rotating drum to be free to rotate for the launch of the introduced hitting balls, and winding the rotating drum for the introduction of the launched hitting balls. A drum drive mechanism operable in a third mode that rotates in a direction and switched to the first mode when the hitting ball is introduced and the coil spring is compressed by the third mode.
Concrete structure inspection device using an unmanned aerial vehicle. According to clause 1,
The structure inspection device further includes a collecting unit provided on the striking unit side,
The collection unit collects striking sound generated when the surface of the structure is struck with the striking ball,
The drum driving mechanism is switched to the first mode or the third mode when the collecting unit collects the hitting by the hitting ball launched in the second mode.
Concrete structure inspection device using an unmanned aerial vehicle.