KR102221620B1 - Portable ultrasound scanner for defect detection of weldments - Google Patents

Abstract

According to an embodiment of the present invention, a mobile ultrasound scanner includes: a rotating shaft; first and second frames which are formed to extend from first and second points spaced apart from each other on the rotating shaft so that one side thereof is perpendicular to the rotating shaft, and allow a transducer to be provided on the other side thereof; a moving part having a hollow into which the rotating shaft is inserted so as to be rotatable about the rotating shaft, and including two pairs of wheels formed in a shape of a disk; and a control part which determines whether or not a defect has occurred in a welding part and the location of the defect based on an analysis result of an ultrasonic signal generated from the transducer. The two pairs of wheels are disposed by being spaced apart from the first and second points by a predetermined distance so that the first and second frames are positioned between the respective pairs of wheels. The moving part further includes a pair of pads formed in a form of being individually wrapped for each pair of wheels and a bearing provided between the rotating shaft and the hollow. In a state where the central portion of the rotating shaft is located above the welding part, as the mobile ultrasonic scanner is moved in the longitudinal direction of the welding part by the moving part, detection of a defect in the welding part may be performed.

Description

PORTABLE ULTRASOUND SCANNER FOR DEFECT DETECTION OF WELDMENTS {PORTABLE ULTRASOUND SCANNER FOR DEFECT DETECTION OF WELDMENTS}

The present invention relates to a mobile ultrasonic scanner for detecting defects of welds that are mutually coupled according to welding between metals to be welded. In more detail, it is possible to determine whether or not a defect has occurred in the weld due to welding for bonding between the target metals and the location of the defect according to the result of analyzing the ultrasonic signal using the ultrasonic transducer, and the shape of a pair of wheels. It relates to a movable ultrasound scanner formed to enable detection of defects in a weld while moving to.

It is obvious that the welded joint of a ship should support its own weight and the weight of the cargo during its lifetime, and have resistance to stress, corrosion, and fatigue cracking, so that it should be the basis for creating economical profits as a means of transportation without accidental breakage. The welding part must first have the strength required by the material, and it must be completed through the correct use of the welding material and the welding work by correct construction, and must satisfy the required quality by investigating and evaluating with a reliable inspection method.

Destructive inspection and non-destructive inspection are applied as inspection methods for welded joints. Destruction inspection is one of the common methods of inspecting whether there is an abnormality in the quality of the weld (whether there are defects such as bubbles or cracks in the welded area). It is possible to inspect the welding condition by sampling and destroying the sampled weld and confirming the welding quality of the fractured part. However, although the fracture test is highly reliable, the production cost increases when it is directly performed on the welded joint, and it is difficult to check the welding condition for the entire welded joint.

As an alternative method, non-destructive testing is widely applied during the production process because it is possible to determine pass or fail according to quality standards by measuring and detecting physical properties that change due to the presence of defects without damaging the weld. That is, if the quality of the welded part, such as the produced part, is used for non-destructive inspection using ultrasonic waves, the above-described problem due to the destructive inspection can be solved.

In the non-destructive inspection by such an ultrasonic flaw detection method, it is possible to simply and easily inspect whether there is an abnormality in welding of parts or the like. In a more detailed description of the welding quality inspection method using ultrasonic waves, after the ultrasonic inspection device is installed on a manufacturing line such as parts, ultrasonic waves are incident on an inspection object having a welded portion, for example, a manufactured part. Then, some ultrasonic waves are propagated into the object to be inspected, and if there is a welding abnormality due to bubbles or cracks in the welded portion, the radio wave signal is partially reflected and returned from that portion. That is, ultrasonic waves travel straight in the same medium, but non-destructive testing is performed using the property of reflecting or refracting due to the difference in physical state and properties (acoustic impedance) of each medium at an interface in contact with another medium. By analyzing the intensity of the reflected echo signal by the ultrasonic inspection device, it is possible to check in real time whether there is an abnormality in the welded part.

However, even if a non-destructive inspection by such an ultrasonic flaw detection method is used, it is not easy to inspect welding defects on parts that are difficult for an operator to access due to safety issues in inspecting a welded part of a large mechanical device such as a ship or a freight car. In other words, during the non-destructive inspection using ultrasonic flaw detection, the probe that generates the ultrasonic wave and the flaw detector to display the location of the defect or the degree of the defect by analyzing the generated ultrasonic wave are used separately. The non-destructive inspection work is carried out in a group by the first worker who performs the task and the second worker who reports the details of the defect and determines whether the work continues or not using a flaw detector that is connected to the probe and receives an ultrasonic signal. It is common.

However, due to safety issues, the inspection of the welding part is neglected because it is difficult for the first and second workers to access the narrow area, such as a ship, which is difficult for workers to approach, the upper area of the wall, and the area of the welding area above the chief. It is revealing the limitations of manual work that is not available.

In addition, even if the size or shape of the ultrasonic flaw detection device is changed in order to reduce the number of workers, a safety problem may occur when the scanning operation is performed by the worker.

Accordingly, development of a technology for detecting a defect in a welding part by a vehicle is continuously required even in an area where it is difficult for a worker to directly approach by using a vehicle for ultrasonic scanning.

Korean Registered Patent Publication No. 10-1915281 (Announcement date: 2018.10.30)

An object of the present invention is to solve the above-described problems, and to provide a movable ultrasound scanner that is formed in a roller shape and is easily movable in the longitudinal direction of the welding portion.

In addition, an object of the present invention is to provide a vehicle for ultrasonic scanning capable of detecting movable welding defects using a vehicle by using the rotation axis of the scanner to one of the front or rear wheels of the vehicle and providing driving force to the remaining wheels.

As an embodiment of the present invention, a mobile ultrasound scanner for detecting defects of welds that are mutually coupled according to welding between metals to be welded may be provided.

The mobile ultrasound scanner according to an embodiment of the present invention is formed to extend from the first and second points spaced apart from each other such that the rotation axis and one side are perpendicular to the rotation axis, and the first and second transducers are provided on the other side. 2 Frame, a moving part including two pairs of wheels formed in the form of a disk, and a hollow into which the rotation shaft is inserted so as to be rotatable about the rotation shaft as an axis, and based on the result of analyzing the ultrasonic signal generated from the transducer, A control unit for determining whether or not a defect has occurred and the location of the defect is included, and the two pairs of wheels are provided by a predetermined distance from the first and second points so that the first and second frames are respectively positioned between each pair of wheels. The wheels are spaced apart, and the moving part further includes a pair of pads formed in the form of individually enclosing each pair of wheels and a bearing provided between the rotating shaft and the hollow, while the central part of the rotating shaft is located above the welding part. As the mobile ultrasound scanner moves in the longitudinal direction of the welding part by the moving part, defect detection of the welding part may be performed.

In the mobile ultrasound scanner according to an embodiment of the present invention, a first transducer for generating an ultrasonic signal is provided in a first frame, and a second transducer for receiving an ultrasonic signal generated from the first transducer is provided in the second frame. A transducer may be provided.

In the mobile ultrasound scanner according to an embodiment of the present invention, the control unit includes a first reference time and a first reference time when the ultrasonic signal generated from the first transducer is transmitted to the second transducer along the welding target metal and the upper surface of the welding part. The ultrasonic signal generated from the transducer is reflected or diffracted from the defect of the welding part based on the second reference time that is reflected from the lower surface of the welding target metal and transmitted to the second transducer. Accordingly, the location of the defect may be derived from the defect passage time transmitted to the first transducer or the second transducer.

In the mobile ultrasound scanner according to an embodiment of the present invention, one end is fixed to the center of the rotating shaft, and the other end is formed to be bent at a predetermined angle, so that a handle capable of being gripped by a user may be further included.

In the mobile ultrasound scanner according to an embodiment of the present invention, an alarm output unit for generating an alarm signal according to whether a defect occurs in the control unit may be further included.

In the mobile ultrasound scanner according to an embodiment of the present invention, a communication unit for transmitting a determination result of whether a defect has occurred and a location of the defect in the control unit to a user terminal may be further included.

As an embodiment of the present invention, a front-wheel drive vehicle for ultrasonic scanning for detecting a defect in a welding part may be provided.

A front-wheel drive vehicle for ultrasonic scanning according to an embodiment of the present invention includes a front wheel on which a pair of front wheels are mounted, a driving module for transmitting driving force to the front wheels, a rear wheel, and a control unit. It is formed to extend from the first and second points spaced apart from each other of the rotation shaft to form a right angle, and the other side is provided with a first and second frame provided with a transducer and a hollow into which the rotation shaft is inserted so as to be rotatable about the rotation shaft, A moving unit including two pairs of wheels formed in the form of a disk is included, and the two pairs of wheels are arranged at a predetermined distance from the first and second points so that the first and second frames are respectively positioned between each pair of wheels. The wheels are arranged spaced apart by a distance, and the moving part further includes a pair of pads formed in the form of individually enclosing each pair of wheels and a bearing provided between the rotating shaft and the hollow, and the control unit further includes an ultrasonic signal generated from the transducer. Based on the analysis result, whether or not a defect has occurred in the welding part and the location of the defect are determined, and detection of a defect in the welding part can proceed according to the movement of the welding part in the longitudinal direction of the vehicle while the central part of the rotation shaft is located above the welding part. .

In the front-wheel drive vehicle for ultrasonic scanning according to an embodiment of the present invention, a photographing unit for photographing a welding part may be further included.

According to the mobile ultrasound scanner for detecting defects of a welding part of the present invention, it is formed in a roller shape and can detect whether there is a defect in welding while moving in the longitudinal direction of the welding part. It has the effect of continuing work while moving the ultrasound scanner.

In addition, by using the rotation axis of the scanner to either the front wheel or the rear wheel of the vehicle and providing the driving force to the remaining wheels, it is possible to safely detect defects in the welding part using the vehicle even if the operator does not directly go to the site. I can.

1 is an exemplary view showing a state in which defect detection of a welding part is performed using a mobile ultrasound scanner according to an embodiment of the present invention.
2 is an exemplary diagram illustrating a process of transmitting an ultrasound signal between transducers in a mobile ultrasound scanner according to an embodiment of the present invention.
3 is an exemplary view showing a moving unit in a mobile ultrasound scanner according to an embodiment of the present invention.
4 is an exemplary diagram of defect information provided to a user terminal from a mobile ultrasound scanner according to an embodiment of the present invention.
5 is an exemplary view showing a front-wheel drive vehicle for ultrasonic scanning according to an embodiment of the present invention.
6 is an exemplary view showing a process of moving a front-wheel drive vehicle for ultrasonic scanning according to an embodiment of the present invention.
7 is an exemplary view showing a detection model in a mobile ultrasound scanner according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily implement the present invention. However, the present invention may be implemented in a number of different forms and is not limited to the embodiments described herein. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and similar reference numerals are attached to similar parts throughout the specification.

The terms used in the present specification will be briefly described, and the present invention will be described in detail.

Terms used in the present invention have selected general terms that are currently widely used as possible while taking functions of the present invention into consideration, but this may vary according to the intention or precedent of a technician working in the field, the emergence of new technologies, and the like. In addition, in certain cases, there are terms arbitrarily selected by the applicant, and in this case, the meaning of the terms will be described in detail in the description of the corresponding invention. Therefore, the terms used in the present invention should be defined based on the meaning of the term and the overall contents of the present invention, not a simple name of the term.

When a part of the specification is said to "include" a certain component, it means that other components may be further included rather than excluding other components unless specifically stated to the contrary. In addition, terms such as "... unit" and "module" described in the specification mean a unit that processes at least one function or operation, which may be implemented as hardware or software or a combination of hardware and software. . In addition, when a part is said to be "connected" with another part throughout the specification, this includes not only the case of being "directly connected", but also the case of being connected "with another element in the middle." In addition, the "length direction" refers to the x-axis direction based on FIG. 1, the "width direction" refers to the z-axis direction based on FIG. 1, and the "vertical direction" refers to the y-axis direction based on FIG. to be. In addition, "upper part" means an upward direction from a vertical direction, and "lower part" means a downward direction from a vertical direction.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

As an embodiment of the present invention, a mobile ultrasound scanner for detecting defects of the welded portions 30 that are mutually coupled according to welding between the metals to be welded 20 may be provided. In the present specification, the welding part 30 is a connection part in which the welding target metal 20 has been welded according to a predetermined welding method, and represents a part where the welding target metal 20 is connected to each other.

1 is an exemplary view showing a state in which defect detection of a welding part 30 is in progress using a mobile ultrasound scanner according to an embodiment of the present invention, and FIG. 2 is a mobile ultrasound scanner according to an embodiment of the present invention. , An exemplary view showing a process of transmitting an ultrasound signal between transducers, and FIG. 3 is an exemplary view showing a moving unit in a mobile ultrasound scanner according to an embodiment of the present invention.

1 to 3, the mobile ultrasound scanner according to an embodiment of the present invention includes a rotation shaft 100, a first and a second spaced apart of the rotation shaft 100 so that one side is at a right angle to the rotation shaft 100. Each of the first and second frames 210 and 220 provided with a transducer and a hollow in which the rotation shaft 100 is inserted so as to be rotatable about the rotation shaft 100 is formed on the other side. It is provided, based on the result of analyzing the ultrasonic signal generated from the moving part and the transducer including two pairs of wheels 600 formed in the form of a disk, the occurrence of a defect in the welding part 30 and the location of the defect are determined. A control unit is included, and the two pairs of wheels 600 include first and second points 101 and 102 so that the first and second frames 210 and 220 are respectively positioned between the pairs of wheels 600. ) Is spaced apart by a predetermined distance, and the wheels 600 are disposed, and in the moving part, a pair of pads 650 formed in the form of individually enclosing each pair of wheels 600 and between the rotation shaft 100 and the hollow The provided bearing 620 is further included, and the welding part 30 is moved by the moving part in the longitudinal direction of the welding part 30 while the central part of the rotating shaft 100 is located above the welding part 30. The defect detection of can proceed.

On the rotation shaft 100, as shown in FIGS. 2 to 3, a pair of frames (the first frame 210 and the second frame 220) are positioned at a predetermined position (the first point 101 and the second point (102) It is formed extending from each. That is, the rotation shaft 100 and the first and second frames may be integrally formed in a'ㅠ' shape.

The user (Ex. worker) applies a force to rotate the moving part while holding the rotation shaft 100 so that the mobile ultrasound scanner of the present invention moves in the longitudinal direction of the welding part 30 to detect a defect in the welding part 30. I can. That is, the rotation shaft 100 may be formed in a grippable size and shape. Here, the grippable size may mean a size that can be held around all or part of the body part 100 with one hand. In addition, the grippable shape may mean a shape configured to be wrapped around all or part of the rotation shaft 100 with one hand. The rotation shaft 100 may be formed in a bar or rod shape as shown in FIGS. 1 to 3, but this is only an example, and if it corresponds to an axis for rotation of the moving part, it may be formed in any shape. Can be formed.

In addition, in the mobile ultrasound scanner according to an embodiment of the present invention, one end is fixed to the center of the rotating shaft 100, the other end is formed to be bent at a predetermined angle, the handle portion 950 that can be gripped by the user. ) May be included. That is, as shown in FIG. 1, when the user moves the handle part 950 in a gripped state, the moving part of the mobile ultrasound scanner of the present invention rotates, and the welding part 30 moves in the longitudinal direction of the welding part 30. Defects can be detected.

As described above, a transducer may be provided on the other side of the first and second frames 210 and 220. That is, as shown in FIG. 2, the transducer may be provided with the first and second frames 210 and 220 to face the welding target metal in order to generate ultrasonic waves or receive the generated ultrasonic waves.

Here, the transducer may be an element or device that converts electrical energy into ultrasonic energy to generate ultrasonic waves based on a piezoelectric effect, or converts the generated ultrasonic waves back into electrical energy. That is, the transducer may be understood as a signal conversion device capable of transmitting and receiving ultrasonic signals. In addition, the transducer may be referred to as a transducer, a vibrator, an ultrasonic probe, or the like.

The transducer may include an ultrasonic insulator, a piezoelectric crystal, an electrode, a damping layer, and the like.

The transducer may be provided in a shape inclined toward the welding target metal 20 at a predetermined angle. The predetermined angle may be determined by various factors such as the type and size of the metal to be welded 20, and the size of the mobile ultrasound scanner.

In addition, a plurality of transducers may be provided in the first and second frames 210 and 220, and the plurality of transducers may be arranged in a predetermined shape.

The moving part may include a plurality of wheels 600 coupled to the rotation shaft 100 so as to be rotatable about the rotation shaft 100 as an axis. Referring to FIG. 3, two pairs of wheels 600 are provided in the form of a disk in the moving part, and a hollow into which the rotating shaft 100 is inserted is provided in the center of the wheel 600. In addition, a bearing 620 is provided between the rotation shaft 100 and the hollow in order to connect the rotation shaft 100 and the hollow.

The two pairs of wheels 600 may further include a pair of pads 650 formed to individually enclose each pair of wheels 600. That is, one pad 650 for each pair of wheels 600 may be formed to surround the circular outer circumferential surface of the wheel 600. The pad 650 may be formed of a rubber material. Alternatively, the pad 650 may be formed of a magnetic material.

In addition, the two pairs of wheels 600 are provided so that the first and second frames 210 and 220 are positioned between each pair of wheels 600, respectively, for this purpose, the rotation shaft 100 as shown in FIG. 3 The wheels 600 may be disposed so as to be spaced apart from the first and second points 101 and 102 by a predetermined distance.

That is, the movable unit includes any one frame of the first frame 210 and the second frame 220 inside the pair of wheels 600 and the pair of wheels 600 on one pad 650. In a form enclosed by, it can be provided in a pair.

In addition, a predetermined liquid may be accommodated in the inner space 670 sealed by the pads 650 and the wheels 600 of the moving part. That is, the inner space 670 may be formed by being sealed by the pad 650, the wheel 600, the bearing 620, and the rotating shaft 100, and the transducer by accommodating the liquid in the inner space 670 The ultrasonic wave generated from may be transmitted through the liquid. _{That is, using a liquid such as water (H 2} 0) as a contact medium for ultrasonic propagation instead of air, ultrasonic waves may be transmitted by immersion testing. In addition to the water, various types of contact media may be used for the liquid. As described above, by accommodating a liquid in the inner space 670 so that ultrasonic waves are transmitted, the efficiency of ultrasonic flaw detection can be improved.

The control unit may control the overall operation of the mobile ultrasound scanner of the present invention. In particular, the control unit analyzes the ultrasonic signal, and based on the analysis result, whether or not a defect has occurred in the welding part 30 and the location of the defect may be determined. That is, the control unit detects the degree of change or discontinuity due to the presence of the defect as the ultrasonic signal generated from the transducer passes through the welding part 30, so that the presence or absence of a defect in the welding part 30 and the location of the defect can be determined. have.

Hereinafter, when a defect occurs in the welding part 30 by the control unit, a process of deriving the location of the generated defect will be described in more detail. As described above, whether or not a defect has occurred may be determined by the controller according to the degree of change of the ultrasonic signal passing through the welding part 30 (eg, difference in acoustic impedance).

First, referring to FIG. 2, in the mobile ultrasound scanner according to an embodiment of the present invention, a first transducer for generating an ultrasound signal is provided in a first frame 210, and a first transducer is provided in the second frame 220. A second transducer for receiving an ultrasonic signal generated from the transducer may be provided.

In addition, in the mobile ultrasound scanner according to an embodiment of the present invention, the controller transmits the ultrasonic signal generated from the first transducer to the second transducer along the upper surface of the welding target metal 20 and the welding part 30. On the basis of the first reference time of which the ultrasonic signal generated from the first transducer is reflected from the lower surface of the metal to be welded 20 and transmitted to the second transducer, the generated from the first transducer is As the ultrasonic signal is reflected or diffracted from the defect of the welding part 30, the location of the defect may be derived from the defect passage time transmitted to the first or second transducer.

That is, _{the location of the defect (g t} ) is determined based on the propagation time of the ultrasonic wave, and as the propagation time of the ultrasonic wave as a reference, the ultrasonic wave is transmitted from the transmitting transducer along the upper surface of the welding target metal 20 to the receiving transformer. The time it takes to propagate to the transducer (first reference time) and the time it takes for the ultrasonic wave to propagate from the transmitting transducer to the receiving transducer after being reflected from the lower surface of the welding target metal 20 (the second reference time) It can be used as the propagation time of ultrasonic waves. Referring to FIG. 2, the propagation path according to the first reference time is the same as the first path 71, and the propagation path according to the second reference time is the same as the second path 73.

The defect passage time is a time transmitted/propagated to the first transducer or the second transducer as the _{ultrasonic signal generated from the first transducer is reflected or diffracted from the defect (g t) of the welding part 30, and the defect passing time} The time may be a time taken for the ultrasonic wave _{to pass through the defect (g t} ) in the welding part 30 and propagate to the receiving transducer. That is, if a defect (g _t ) exists in the welding part 30, the generated ultrasonic signal _{may be reflected or diffracted after being transmitted to the defect (g t} ), and thus, the generated ultrasonic signal may be reflected or diffracted again to the first transducer according to the reflection or diffraction. It may be propagated, or may be propagated to the second transducer according to reflection or diffraction. There are various types of defects caused by welding that may occur in the welding part 30, such as bubbles and cracks, and are not limited to the type of specific defects. In addition, referring to FIG. 2, the propagation path according to the defect passage time is the same as the defect propagation path 72.

When the defect passage time is measured, the position (first position) of the defect in the welding part 30 may be determined based on a trigonometric relationship between the first reference time and the second reference time of the defect passage time.

In the control unit, when the position of the defect in the welding part 30 is determined according to the above-described process, the functions of the first and second transducers may be controlled so that the functions of the first transducer and the second transducer are mutually changed.

Preferably, when the position (first position) of the defect in the welding part 30 is first determined in the control unit, an ultrasonic signal is generated from the second transducer, and the first transducer receives the generated ultrasonic signal. A first reference review time in which the ultrasonic signal generated from the second transducer is transmitted to the first transducer along the upper surface of the welding target metal 20 and the welding part 30; And the ultrasonic signal generated from the second transducer is reflected from the bottom surface of the metal to be welded 20 and transmitted to the first transducer based on the first reference review time. A review process in which the second position of the defect is derived from the defect passage time transmitted to the second transducer or the first transducer as it is reflected or diffracted from the defect of the welding part 30 may be performed.

That is, as the first transducer and the second transducer perform both the roles/functions of the ultrasonic transmitter and the receiver, respectively, the location of the defect may be derived twice. In other words, when the first transducer and the second transducer serve as an ultrasonic transmitter and a receiver, respectively, the first position derived as the location of the defect, and the first and second transducers are each of the ultrasonic receiver and the transmitter. When playing a role, the control unit may determine whether to determine the location of the defect again according to whether the second location derived as the location of the defect coincides.

More specifically, if the control unit determines that the separation distance between the first position and the second position is within the reference position (Ex. 1mm), the control unit can determine that the first position and the second position are identical. have. Contrary to this, if the control unit determines that the separation distance between the first and second positions is farther than the reference position, the control unit determines that the first and second positions do not coincide, and the position of the defect is re-established. It can be controlled by what needs to be determined.

As described above, as the process of determining the defect location is repeatedly performed according to the reversed role of the transducer, the location of the defect can be more accurately determined.

In the mobile ultrasound scanner according to an embodiment of the present invention, an alarm output unit for generating an alarm signal according to whether a defect occurs in the control unit may be further included.

That is, when the control unit determines that a defect has occurred, an alarm signal is generated by the control unit of the mobile ultrasound scanner of the present invention and may be output by an alarm output unit (not shown) provided in advance in the mobile ultrasound scanner of the present invention. The alarm signal may be output in various forms. For example, the alarm signal may include a voice signal, a vibration signal, a display signal, and the like, but these are only exemplary and may be output in any form to notify the user of the occurrence of a welding defect.

In the mobile ultrasound scanner according to an embodiment of the present invention, a communication unit for transmitting a determination result of whether a defect has occurred and a location of the defect in the control unit to a user terminal may be further included. The communication unit may perform communication between components in the mobile ultrasound scanner as well as communication with other devices such as a user terminal or other systems. The communication method of the communication unit may be various wired or wireless communication methods, and is not limited to a specific communication method.

The user terminal may be a supervisor (second user) terminal that reports or supervises a work status in one pair with an operator (first user) using another mobile ultrasound scanner according to an embodiment of the present invention. That is, during the non-destructive inspection using ultrasonic waves, the operator (first user) who scans the defect while holding the handle part 950 of the portable ultrasonic scanner of the present invention while moving in the longitudinal direction of the welding part 30 also performs the present invention in real time. The defect information (whether or not the defect has occurred and the location of the defect) can be checked through the display unit (not shown) provided in the mobile ultrasound scanner of, but the worker (first user) is separated by a predetermined distance from the worker (first user). Since the supervisor (the second user) who is supervising the current status of the work of the worker may also need to check the determined defect information using the mobile ultrasound scanner, the defect information may be provided to the supervisor terminal using the above-described communication unit.

That is, in the mobile ultrasound scanner of the present invention, a pair of two people usually enters the areas in a narrow area, such as a ship, which is difficult for an operator to approach, an upper area of the wall, and an area of the welding part 30 on the chief. In order to solve possible problems during the ongoing non-destructive inspection, only one of the two (the first user) enters the areas to perform the scanning operation, and the other one (the second user) is the communication unit of the mobile ultrasound scanner. The location of the defect can be identified in real time based on the information transmitted through. In other words, if the mobile ultrasound scanner of the present invention is used, even in the case of non-destructive inspection using ultrasound in a narrow area, the first user secures the work area while grasping the location of the defect in real time and scanning. 2 The user can also check the work result from the first user in real time using the device of the second user (supervisor terminal) in a safe place.

4 is an exemplary diagram of defect information provided to a user terminal from a mobile ultrasound scanner according to an embodiment of the present invention.

Referring to FIG. 4, defect information (whether or not a defect has occurred and the location of the defect) from a control unit may be provided to a user terminal through a communication unit of the mobile ultrasound scanner of the present invention. That is, as shown in (a) of FIG. 4, _{the extent of the defect spaced from the center 310 of the welding part 30 in the left (g l} ) or right (g _r ) direction with respect to the location of the defect and the welding part A state in which the depth d from the upper surface of 30 to the defect is displayed may be provided to the user terminal.

In more detail, the presence or absence of the defect and the location of the defect can be confirmed at a time when the central portion of the rotation shaft 100 of the mobile ultrasound scanner of the present invention is located above a specific point in the welding part 30.

Preferably, in the defect information that can be identified in the user terminal, a plurality of points are displayed in a coordinate form in which a plurality of points are uniformly arranged, and at the points, center points (1, 2, 3) indicated only by numbers to indicate the center of the welding part 30. , 4), separation points (L1, LL2, R3) by combining letters (L, R) and numbers to indicate the degree of separation from the center of the weld 30 to the left (g _l ) or right (g _{r ).} , RR4, etc.), and the number for indicating the center point and the separation point is for indicating the depth from the upper surface to the lower bottom surface of the welding part 30, and the greater the number, the deeper the depth. , The letters (L, R) for indicating the separation point may be displayed so that the number of the letters increases as the degree of separation from the center increases. For example, as in (a) of FIG. 4, the center point (1) is closer to the upper surface of the weld 30 than the center point (4), and the separation point (RR1) is compared to the separation point (R1). It is spaced apart from the center of the weld 30 to the right (g _{r ).}

In addition, a point corresponding to the location of the defect among the center point and the separation point may be displayed in a different color from other points or may be displayed to be flickering. For example, when the separation point RR4 is displayed in a color different from other points or blinks in (a) of FIG. 4, the separation point RR4 point (the rightmost and deepest point from the center of the weld 30) It can be determined that there is a defect in the welding part 30 in ).

That is, in the mobile ultrasound scanner of the present invention as shown in FIG. 4A, the location of the defect of the welding part 30 is provided to the user terminal using a combination of numbers and letters, so that the user can intuitively determine the location of the defect in real time. There is an effect that can be grasped.

In addition, in the mobile ultrasound scanner of the present invention, the ultrasound signal itself received by the transducer at the receiving side can be provided to the user terminal by passing through the point where the defect has occurred (including reflection or diffraction) as shown in FIG. 4B. .

In addition, the mobile ultrasound scanner according to an embodiment of the present invention may further include a data storage unit for storing information on whether a defect has occurred, including an ultrasound signal, and a location of the defect. The data storage unit may be a database management system (DBMS) for interworking with a database and accessing data in the database.

In addition, the control unit may additionally determine the degree of occurrence of a defect in the welding part 30 by using the detection model 700.

Preferably, the control unit can determine the degree of defect occurrence from the image data using the detection model 700 learned in advance according to the deep learning algorithm, and the image data is acquired as the image is converted from the ultrasonic signal through the frequency conversion technique. Can be. The ultrasonic signal may be data of various types, but hereinafter, the ultrasonic signal will be described on the assumption that the ultrasonic signal is time-series data.

More specifically, the ultrasonic signal may be filtered by a filter unit (not shown) before being converted into image data by the control unit. The filter unit may include at least one of a high-pass filter, a low-pass filter, a band-pass filter, a matching filter, or the filters, and filtering may be performed by a combined filter. In addition, the control unit may additionally perform sampling. That is, the ultrasonic signal may be sampled in units of a predetermined time interval, and the time interval may be set to 10 [ms] as a time for the control unit to appropriately convert the image data. However, since this is only an example, the time interval may be set to various values according to actual implementation.

The controller may generate image data for the ultrasonic signal according to an image conversion process. That is, the image data may be an image obtained using a frequency conversion technique. Various methods may be used for the frequency transformation of the ultrasonic signal, but it is preferable to use a Fast Fourier Transform (FFT) method for the frequency transformation. That is, as the ultrasonic signal is frequency-converted according to the FFT method, the intensity of each frequency component can be expressed as a frequency spectrum, and the image data can be generated by converting it into an image form. Hereinafter, a description will be made based on image data generated according to the result of the FFT transformation.

Next, the control unit may determine the degree of occurrence of a defect in the welding part 30 by using the detection model 700. The degree of occurrence of the defect may be classified into a plurality of classes, and a classified result may be derived. For example, the degree of defect occurrence can be classified into five classes (Class 1-5).

The detection model 700 is generated according to a result of pre-learning the relationship between image data and the degree of defect occurrence according to a deep learning algorithm, and the deep learning algorithm may include a convolutional neural network (CNN). In addition, the detection model 700 may be generated according to a learned result by combining with a recurrent neural network (RNN) in addition to the CNN. Hereinafter, a description will be made based on the detection model 700 formed according to the CNN-based learning result. The degree of defect occurrence relates to the degree of progression of defects generated according to the corresponding welding obtained in advance with respect to the image data, and can be classified into five classes for each image data.

First, briefly describing CNN, CNN is a type of artificial neural network used to analyze input data (mainly, visual images). Features are extracted from the input data and input data based on the extracted features. Can be classified as to which class is applicable. The CNN may include at least one or more convolutional layers, a pooling layer, and a fully connected layer.

The convolution layer may correspond to a filter that generates a feature map representing features of an object through a convolution operation. That is, the CNN can detect the characteristics of the image data by detecting in what form a local pattern forming the image data exists with respect to the image data input to the convolutional layer. The pattern may correspond to a feature existing between adjacent pixels, such as a shape, wave height, period, etc. of a waveform in the image data. A stride may be performed to find a feature in the image data, and a stride size used in the convolution layer may be variously set.

In the pooling layer, a pooling operation may be performed to reduce the size of the output data of the convolution layer or to emphasize specific data. The pooling layer may include a max pooling layer and an average pooling layer.

The fully connected layer may correspond to a classfier for classifying input data based on the extracted feature information.

The detection model 700 is preferably a first neural network 710 for extracting a first feature from image data, and a second neural network 720 for extracting a second feature from image data, as shown in FIG. 7. , The classification layer 740 for determining whether a defect occurs based on the extracted first feature and the second feature, and the outputs of the first neural network 710 and the second neural network 720 are fused to the classification layer 740. A fusion layer 730 formed to be input may be further included.

The first neural network 710 may correspond to a neural network formed based on a convolutional neural network (CNN) including a single convolutional layer. That is, the first neural network 710 is formed in a shallow structure with only the first convolution layer and the first pooling layer as shown in FIG. 6, so that the first feature can be extracted from the input image data. have.

Unlike this, the second neural network 720 may correspond to a neural network formed based on a convolutional neural network including a plurality of convolutional layers. That is, the second neural network 720 is formed in a deep structure with second to fourth convolution layers and a second pooling layer, as shown in FIG. 6, and has a second characteristic from the input image data. Can be extracted.

A neural network including only one convolutional layer may correspond to a shallow neural network as described above, and a neural network including a plurality of convolutional layers may correspond to a deep neural network. Accordingly, the first feature extracted from the shallow structure of the first neural network 710 may be a shallow feature, and the second feature extracted from the deep structure of the second neural network 720 may be a deep feature.

The fusion layer 730 may be a layer that combines the outputs of the first neural network 710 and the second neural network 720 and connects them to become an input of the classification layer 740. The fusion layer 730 may be formed of a pooling layer.

The classification layer 740 is a fully connected layer as described above, and the classification layer 740 includes at least one hidden layer and an output layer, as well as a platen layer for dimension change. (flatten layer) may be additionally included. The softmax activation function is used in the output layer, so that the degree of occurrence of defects due to welding can be determined.

In more detail, in the first neural network 710, a single first convolutional layer 711 and a first pooling layer 712 are formed together to form a shallow convolutional neural network. In contrast, the second neural network 720 includes three convolutional layers corresponding to the second convolutional layer 721, the third convolutional layer 722, and the fourth convolutional layer 723, and a second pooling layer. 724) may be connected to form a deep convolutional neural network. The number of filters and the filter size of the first to fourth convolution layers may be the same or may be set differently.

When the structure of the detection model 700 is determined based on the features extracted from the shallow and deep neural networks, respectively, as shown in FIG. 7, compared to the determination result according to the convolutional neural network of the general structure. You can get more accurate results. That is, after the feature extraction from the image data was separately performed through the two convolutional neural networks, a more accurate degree of defect occurrence was determined according to the result of fusion in the fusion layer 730.

In other words, by using the mobile ultrasound scanner of the present invention to determine not only the location of the defect, but also the degree of progression of the defect generated using the detection model 700 in detail, an efficient non-destructive inspection using ultrasonic waves can be performed. .

As an embodiment of the present invention, a front-wheel drive vehicle 950 for ultrasonic scanning for detecting defects of the welding part 30 may be provided. The above-described mobile ultrasound scanner may be applied to the front wheel driving vehicle 950 for ultrasound scanning, and the same content as the mobile ultrasound scanner will be omitted below.

The front-wheel drive vehicle 950 for ultrasonic scanning according to an embodiment of the present invention is a safety problem that may occur in a narrow area, such as a ship, that is difficult for an operator to approach, an upper area of the wall, and an area of the weld 30 on the chief In order to solve the problem, it may be provided in the form of a vehicle. That is, the user goes to the areas and moves the scanning device directly using a predetermined scanning device, and does not detect the defect of the welding part 30, but allows the ultrasonic scanning operation to be performed through the vehicle, thereby ensuring the safety of the operator. Can be secured.

5 is an exemplary view showing a front-wheel drive vehicle 950 for ultrasonic scanning according to an embodiment of the present invention.

5, the front wheel driving vehicle 950 for ultrasonic scanning according to an embodiment of the present invention includes a front wheel on which a pair of front wheels are mounted, a driving module for transmitting driving force to the front wheel, a rear wheel, and a control unit, The rear wheel is formed to extend from the first and second points spaced apart from each other such that the rotation shaft 100 is at a right angle to the rotation shaft 100, and the other side has the first and second transducers. A frame and a hollow into which the rotation shaft 100 is inserted so as to be rotatable about the rotation shaft 100 is provided, a moving part including two pairs of wheels 600 formed in a disk shape is included, and two pairs of wheels 600 The wheels 600 are spaced apart from the first and second points by a predetermined distance so that the first and second frames are respectively positioned between each pair of wheels 600, and each pair of A pair of pads 650 formed in the form of individually enclosing the wheel 600 and a bearing 620 provided between the rotating shaft 100 and the hollow are further included, and the control unit analyzes the ultrasonic signal generated from the transducer. Based on the result, whether or not a defect has occurred in the welding part 30 and the location of the defect is determined, and moving in the longitudinal direction of the welding part 30 of the vehicle while the central part of the rotating shaft 100 is located above the welding part 30 According to this, the defect detection of the welding part 30 may proceed.

In particular, the pad 650 may be formed to include not only a rubber material, but also a magnetic material or a power source for providing magnetic force to the pad 650. That is, even in an area that is difficult for a user to access (for example, an area with a steep slope), welding is generally performed on metal, so that the vehicle is operated in close contact with the metal by magnetic force, so that the welding part 30 is stably operated. Can detect defects.

6 is an exemplary view showing a process of moving the front-wheel drive vehicle 950 for ultrasonic scanning according to an embodiment of the present invention.

6, the front-wheel drive vehicle 950 for ultrasonic scanning of the present invention is provided with components (transducers, etc.) for ultrasonic flaw detection on the rear wheel, so that from the starting point 31 of the welding part 30 to the destination point Up to (32), there may be an area in which welding failure cannot be detected. That is, when the vehicle of the present invention moves from the starting point 31 to the destination point 32, the first area 34 corresponding to the point where the rear wheel is located is whether a defect occurs due to the rear wheel provided with the transducer, and It will be possible to determine the location of the defect. On the contrary, when the vehicle of the present invention moves to the destination point 32, the second area 33 from the point where the rear wheel is located to the destination point 32 may be difficult to discriminate such as occurrence of a defect due to the rear wheel. .

In order to solve the above problems, in the case where the vehicle of the present invention moves from the starting point 31 to the arrival point 32, the control unit rotates the vehicle so that the direction from the arrival point 32 to the starting point 31 By moving to, it is possible to control to determine whether or not a defect has occurred in the second area 33 and the location of the defect.

In addition, in the front-wheel drive vehicle 950 for ultrasonic scanning according to an embodiment of the present invention, a photographing unit (not shown) for photographing the welding part 30 may be further included. The photographing unit may be provided at a predetermined position in the vehicle to photograph the welding unit 30 provided under the vehicle. In addition, the control unit may perform additional defect detection on the welding image acquired by the photographing unit.

In addition, the control unit may use the welding image to determine whether the vehicle of the present invention is moving with the welding part 30 positioned at the center of the vehicle. That is, the control unit may control the moving speed and steering of the vehicle in order to position the vehicle in the center of the welding part 30 according to the result of analyzing the welding image.

The above description of the present invention is for illustrative purposes only, and those of ordinary skill in the art to which the present invention pertains will be able to understand that other specific forms can be easily modified without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative and non-limiting in all respects. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as being distributed may also be implemented in a combined form.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention defined in the following claims are also present. It belongs to the scope of rights of That is, the scope of the present invention is indicated by the claims to be described later rather than the detailed description, and all changes or modified forms derived from the meaning and scope of the claims and the concept of equivalents thereof should be interpreted as being included in the scope of the present invention. do.

20: welding target metal
30: weld
100: axis of rotation
200: frame
600: wheel
620: bearing
650: pad
700: detection model
900: handle
950: Front-wheel drive vehicle for ultrasonic scanning

Claims (8)

In the mobile ultrasonic scanner for detecting defects of welds that are mutually coupled according to welding between metals to be welded,
Rotating shaft;
First and second frames each extending from first and second points spaced apart from each other of the rotation shaft so that one side is perpendicular to the rotation shaft, and a transducer is provided on the other side;
A moving part including two pairs of wheels formed in a disk shape and provided with a hollow into which the rotation shaft is inserted so as to be rotatable about the rotation shaft as an axis; And
A control unit for determining whether a defect occurs in the welding part and a location of the defect based on the result of analyzing the ultrasonic signal generated from the transducer is included,
The two pairs of wheels are spaced apart from the first and second points by a predetermined distance so that the first and second frames are respectively positioned between each pair of wheels, and the wheels are disposed,
A pair of pads formed in the form of individually enclosing each pair of wheels on the moving part; And a bearing provided between the rotary shaft and the hollow,
In a state in which the central part of the rotation shaft is located above the welding part, as the mobile ultrasonic scanner is moved in the longitudinal direction of the welding part by the moving part, defect detection of the welding part proceeds,
In the control unit, the degree of defect occurrence can be determined from image data using a detection model, and the image data can be obtained by image conversion from the ultrasonic signal through a frequency conversion technique,
The detection model is generated according to a result of pre-learning about the relationship between image data and the degree of defect occurrence according to a deep learning algorithm,
The detection model includes a first neural network for extracting a first feature from the image data;
A second neural network for extracting a second feature from the image data;
A classification layer for determining a degree of defect occurrence based on the extracted first and second features; And
And a fusion layer formed such that outputs of the first neural network and the second neural network are fused to be input to the classification layer,
The first neural network is a shallow convolutional neural network including a single convolutional layer, and the second neural network is a deep convolutional neural network including a plurality of convolutional layers,
The first frame includes a first transducer generating a first ultrasonic signal,
The second frame includes a second transducer generating a second ultrasonic signal,
The first transducer receives the second ultrasonic signal, the second transducer receives the first ultrasonic signal,
The control unit,
The first position of the defect is derived based on the first ultrasonic signal, the second position of the defect is derived based on the second ultrasonic signal, and the defect is based on the first position and the second position. Derive whether or not to re-measure the position of,
The control unit,
When the separation distance between the first position and the second position is within a reference distance, it is determined that the first position and the second position coincide, and the position of the defect is displayed through a user terminal,
The control unit,
When the separation distance is farther than the reference distance, it is determined that the first position and the second position do not match, and the position of the defect is measured again. The method of claim 1,
Further comprising a communication unit for transmitting the determination result of the occurrence of the defect and the location of the defect in the control unit to the user terminal,
The communication unit,
Transmitting a plurality of points for displaying the location of the defect on the user terminal to the user terminal,
The plurality of points,
A center point indicating the center of the weld and
It includes a separation point indicating a degree of separation from the center of the weld to the left or right,
The location of the defect is,
A mobile ultrasound scanner that is displayed on the user terminal through the center point and the separation point. The method of claim 1,
In the control unit,
A first reference time during which the ultrasonic signal generated from the first transducer is transmitted to the second transducer along the upper surface of the welding target metal and the welding part; And a second reference time in which the ultrasonic signal generated from the first transducer is reflected from the lower surface of the metal to be welded and transmitted to the second transducer,
As the ultrasonic signal generated from the first transducer is reflected or diffracted from a defect in a welding part, the first position is derived from a defect passage time transmitted to the first or second transducer. The method of claim 1,
One end is fixed to the center of the rotation shaft, the other end is formed to be bent at a predetermined angle, the mobile ultrasound scanner further comprises a handle that can be gripped by a user. The method of claim 1,
An ultrasound scanner further comprising an alarm output unit that generates an alarm signal according to whether a defect occurs in the control unit. delete delete delete

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