KR100967084B1 - Crack Monitoring System, Crack Monitoring Method and Computer Readable Medium on which Crack Monitoring Program is Recorded - Google Patents

Abstract

The present invention relates to a computer-readable medium recording a crack monitoring system, a crack monitoring method, and a crack monitoring program. The crack monitoring system according to the present invention is a crack monitoring for monitoring cracks occurring in a test specimen under load. The system includes a plurality of acceleration sensing units, a plurality of noise sensing units, a crack position tracking unit, and a display unit. A plurality of acceleration detectors are installed in the test object to detect the acceleration. A plurality of noise detectors are installed around the test object to detect the noise. The crack position tracking unit detects the time when the crack occurred from the acceleration signal detected by the plurality of acceleration detectors, the time when the noise caused by the crack detected from the noise signal detected by the plurality of noise detectors, and the plurality of The location of the crack is tracked using the relative position from the test specimen of the noise detector. The display unit displays the crack position tracked in the crack position tracking unit in real time.

Crack, monitoring, load, noise

Description

Crack Monitoring System, Crack Monitoring Method and Computer Readable Medium on which Crack Monitoring Program is Recorded}

The present invention relates to a computer readable medium recording a crack monitoring system, a crack monitoring method and a crack monitoring program.

Structures such as aircraft, ships, and vehicles are made of metal materials such as iron and aluminum, composite materials, and the like. When loads are repeatedly applied to such structures, cracks may occur in stress concentration areas due to fatigue. If a crack occurs during operation of these structures and even damages of the structures, it leads to a large accident. Therefore, these structures are subjected to a structural test applying a load at the manufacturing stage to identify the position where cracks occur, and to design a feedback such as to further increase mechanical strength and the like.

Conventionally, various methods have been tried to grasp the position where a crack occurs. For example, in non-destructive testing, ultrasonic waves may be used to locate defects within a material. However, this method has a limitation that it can detect only local parts of the material. In addition, a method of inspecting a crack of a concrete structure includes visual inspection and ultrasonic exploration. In the case of visual inspection, there is an advantage in that it is possible to identify the externally generated cracks with certainty, but there is a disadvantage in that the internal cracks cannot be identified. In addition, there are not many technicians for exploring such cracks, and it is very cumbersome and labor intensive to perform visual inspection one by one. On the other hand, the ultrasonic detection method for detecting the internal crack is being carried out, but this has the disadvantage that the reliability is not great.

In addition, in the case of very large structures such as an aircraft, it is not easy to determine the location of the cracks by visual inspection or ultrasonic inspection described above at the time of their structural test, and it is impossible in terms of time and cost. Can also say.

In addition, in the above-mentioned method, it was impossible to grasp | ascertain the crack which arises at the time of a structural test in real time, and it was only possible to grasp | ascertain the position of a crack through the data analysis performed afterwards.

Therefore, it can be said that there is a need for a system that can easily grasp in real time the crack generated in the structural test for a large structure such as an aircraft.

The present invention is to solve the above problems, the problem to be solved by the present invention is a computer-readable medium recording a crack monitoring system, a crack monitoring method and a crack monitoring program that can monitor the crack of the structure. To provide.

Another object of the present invention is to provide a computer-readable medium recording a crack monitoring system, a crack monitoring method, and a crack monitoring program that can monitor cracks occurring in a structure in real time during structural testing. .

The problem to be solved by the present invention is not limited to the above-mentioned problem, another problem to be solved by the present invention not mentioned here is those skilled in the art from the following description. Will be clearly understood.

The crack monitoring system which is an invention of Claim 1 is a crack monitoring system which monitors the crack which generate | occur | produces to the test object to which load is applied, and includes a some acceleration detection part, a some noise detection part, a crack position tracking part, and a display part. . A plurality of acceleration detectors are installed in the test object to detect the acceleration. A plurality of noise detectors are installed around the test object to detect the noise. The crack position tracking unit detects the time when the crack occurred from the acceleration signal detected by the plurality of acceleration detectors, the time when the noise caused by the crack detected from the noise signal detected by the plurality of noise detectors, and the plurality of The location of the crack is tracked using the relative position from the test specimen of the noise detector. The display unit displays the crack position tracked in the crack position tracking unit in real time.

By such a configuration, the present invention, by accurately detecting the acceleration change due to the generation of the crack by the acceleration detection unit, it is possible to trigger only the noise due to the crack of the noise heard during the test, the triggered noise (that is, to the crack Noise), the location of the crack can be tracked by the time delay calculation of the crack and displayed in real time.

In the crack monitoring system of the inventor of Claim 2, a display part displays the tracked crack position in real time on the 2D drawing or 3D cad data of a test object.

According to this configuration, the present invention marks and displays the crack position in real time on the two-dimensional drawing data or the three-dimensional cad data of the test specimen. Thus, the tester simultaneously monitors the position of the crack on the drawing data and the like during the test. can do.

The crack monitoring system according to claim 3 further includes an image photographing unit, the image photographing unit photographing the front surface, the plane, and the right side surface of the test object, and the display unit photographing the tracked crack position by the image photographing unit. Displays images, plane images and right side images in real time.

With this configuration, the present invention marks and displays the location of the cracks on the test image data of the test specimen in real time, thereby providing a more realistic visual effect to the tester, and the test image starts the cracking to the breakage. Because it includes an image of, it is possible to provide more realistic visual effects than to display in the drawing data.

In the crack monitoring system of the invention according to claim 4, the display unit displays the load applied to the test body in real time.

According to such a structure, this invention can grasp | ascertain the test result, such as a crack generate | occur | producing at some load, in real time.

The crack monitoring method which is an inventor of Claim 5 is a crack monitoring method which monitors the crack which generate | occur | produces in the test object under load, and includes an acceleration detection step, a noise detection step, a crack position tracking step, and a display step. In the acceleration detection step, the acceleration is detected by a plurality of acceleration detection units installed in the test object. The noise detection step detects noise by a plurality of noise detectors installed around the test object. The crack position tracking step may include a time at which a crack occurs from an acceleration signal detected by a plurality of acceleration detectors, a time at which noise by a crack detected from a noise signal detected by the plurality of noise detectors is detected, and a plurality of The location of the crack is tracked using the relative position from the test specimen of the noise detector. The marking step displays in real time the crack location tracked in the crack location tracking step.

By such a configuration, the present invention, by accurately detecting the acceleration change due to the generation of the crack by the acceleration detection unit, it is possible to trigger only the noise due to the crack of the noise heard during the test, the triggered noise (that is, to the crack Noise), the location of the crack can be tracked by the time delay calculation of the crack and displayed in real time.

The computer-readable medium which recorded the crack monitoring program which is the inventor of Claim 6 is a computer-readable medium which recorded the crack monitoring program which monitors the crack which generate | occur | produces to the test object under load, and this crack monitoring program is acceleration The detection phase, the noise detection phase, the tracking phase and the display phase are executed. In the acceleration detection step, the acceleration is detected by a plurality of acceleration detection units installed in the test object. The noise detection step detects noise by a plurality of noise detectors installed around the test object. The crack position tracking step may include a time at which a crack occurs from an acceleration signal detected by a plurality of acceleration detectors, a time at which noise by a crack detected from a noise signal detected by the plurality of noise detectors is detected, and a plurality of The location of the crack is tracked using the relative position from the test specimen of the noise detector. The marking step displays in real time the crack location tracked in the crack location tracking step.

By such a configuration, the present invention, by accurately detecting the acceleration change due to the generation of the crack by the acceleration detection unit, it is possible to trigger only the noise due to the crack of the noise heard during the test, the triggered noise (that is, to the crack Noise), the location of the crack can be tracked by the time delay calculation of the crack and displayed in real time.

As described above, the present invention, by accurately detecting the acceleration change due to the generation of the crack by the acceleration detection unit, it can only trigger the noise caused by the crack of the noise heard during the test, the triggered noise (that is, the noise caused by the crack ), The location of the crack can be tracked by the time delay calculation of the crack and displayed in real time, so that the location of the crack occurring in the test specimen during the structural examination can be monitored in real time.

Specific matters other than the problem to be solved, the problem solving means, and the effects of the present invention as described above are included in the following embodiments and the drawings. Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. Like reference numerals refer to like elements throughout.

Hereinafter, with reference to the accompanying drawings, a specific embodiment according to the present invention will be described.

1 is a view schematically showing a crack monitoring system according to an embodiment of the present invention.

As shown in FIG. 1, the crack monitoring system 100 according to an exemplary embodiment of the present invention may include an acceleration detector 110, a noise detector 120, an image photographing unit 130, and a crack position tracking unit 140. ) And the display unit 150.

When the plurality of acceleration detection unit 110 is installed in the test body (specifically attached to the test body) and cracks occur in any part of the test body during the structural test, the acceleration detection unit 110 detects an acceleration change due to the crack generation. The acceleration detector 110 may actually use an accelerometer. 2 is a photograph showing that the accelerometer is installed on the actual test body.

The noise detector 120 detects noise generated during a structural test by installing a plurality of pieces around the specimen (specifically, apart from the specimen around the specimen). By the way, the noise generated during this structural test may be due to cracks, and other noises may be included. Therefore, it is necessary to select only the noise due to the crack, which is the noise of the present invention, among the noises detected by the noise detector. This is done in the crack position tracking unit 130 described later. The noise detector 120 may actually use a microphone. 3 is a photograph showing that the microphone is installed around the actual test specimen.

The image capturing unit 130 is installed at the front, the upper, and the right side of the test body, and photographs the front, top, and right side of the test body while the test is in progress. Furthermore, other shavings besides these three sides can of course be taken.

The crack location tracking unit 140 tracks the crack location by using the acceleration data detected by the acceleration detector 110 and the noise data detected by the noise detector 120. The crack position tracking algorithm will be described below. In the present invention, it is possible to think of the sound source detection algorithm because it is performed by grasping the noise occurrence position due to the crack in tracking the crack position.

4 schematically illustrates a crack location tracking algorithm. If a crack occurs in any part of the specimen and an acceleration change occurs at that part, the acceleration change is detected by an accelerometer attached near the crack part. Thus, the acceleration data detected by the accelerometer is a graph denoted by Acc in FIG. 4.

In addition, when four microphones among the plurality of microphones detect noise due to cracking, the first microphone is Mic 1, the second microphone is Mic 2, the third microphone is Mic 3, and the fourth microphone is Mic. 4, each of these detected noise data is shown graphically. According to each graph, the first microphone detected noise after a time t1 had elapsed from the time the crack occurred, the second microphone detected noise after t2 time elapsed from the time the crack occurred, and the third microphone had a crack. The noise was detected after a time t3 had elapsed from this time point, and the fourth microphone detected the noise after a time t4 had elapsed from the time point at which the crack occurred.

Therefore, when a circle (actually a sphere) is drawn with a radius obtained by multiplying the sound speed (c) by t1 based on the position of the first microphone, a crack exists at any position on the circumference. When these operations are carried out on the second to fourth microphones in turn, a total of four circles (spheres) are drawn, and the position where all four circles (spheres) overlap is estimated as a position where a crack has occurred as a result. This position is indicated as the estimated source position in FIG. 4.

In the crack position tracking unit 140 for performing such a task, a computer may be used.

The display unit 150 displays the crack position tracked by the crack position tracking unit 140 in real time while the test is in progress. This display method may be various. The crack position may be marked and displayed on the two-dimensional drawing of the specimen, the front view, the plan view, and the right side view, or the fracture position may be marked and displayed on the three-dimensional cad data of the specimen. have. Furthermore, the crack position may be marked and displayed on the real image data photographed by the image capturing unit. In addition, the display unit 150 may display the load applied to the test body in real time while the test is in progress.

The contents of the simulation test will be described below. The simulation test was performed by applying five hits to each of the test specimens at random, two times for each of them. Each of these strikes is called an event. 5 is a diagram capturing a screen displayed on the display unit 150 during the simulation test. As shown in Fig. 5, the crack position is marked in red on the front view, the top view, and the right side view of the test body. 6 is a diagram capturing a screen displayed on the display unit 150 when the test is completed. As shown in FIG. 6, a total of 10 events occurred, all of which are marked in red on the front view, the top view, and the right side view of the test object.

In addition, the lower end of FIGS. 5 and 6 includes a table in which the measurement information on the event, the occurrence time, the corresponding load, the tracked crack position, the x, y, z coordinates, the noise level due to the crack, and the like are arranged in real time in a table form. Is shown. This is shown in FIG. 7 as a table separately. 7 is a crack information table displayed on the display unit 150. In Fig. 7, the loads are all represented by 0, because the simulation does not apply the load but only generates the cracking sound by the hitting, and the same color indicates the same hitting position and is applied to all five sites. Because of the blow, it consists of 5 pairs. As shown in FIG. 7, the test result of the two hits for the same position was possible to measure within the 100 mm error range.

8 is a signal processing flowchart according to the present invention. As shown in FIG. 8, the present invention performs acceleration triggering when an acceleration signal is detected by an acceleration detector, and performs microphone triggering when a sound signal is detected by the noise detector to crack. Choose only microphones that detect noise by The delay time is calculated based on the first triggered microphone, the crack initial position is set, the estimated crack position is estimated using the microphone coordinates, and the value obtained by subtracting the estimated crack position from the crack initial position is within the error range. When these values converge, the estimated crack positions are mapped and output on the drawing of the test object. In FIG. 8, the sound source position means a crack position.

8 is a flowchart showing a crack monitoring method according to the present invention. As shown in FIG. 8, the crack monitoring method according to the present invention includes an acceleration detection step, a noise detection step, a crack position tracking step, and a display step. In the acceleration detection step, the acceleration is detected by a plurality of acceleration detection units installed in the test object. In the noise detection step, noise is detected by a plurality of noise detectors installed around the test object. In the crack position tracking step, the time when a crack occurs from the acceleration signal detected by the plurality of acceleration detectors, the time when the noise due to the crack detected from the noise signal detected by the plurality of noise detectors, and the plurality of noises are detected. The position of the crack is tracked using the relative position from the test body of the detector. In the display step, the crack position tracked by the crack position tracking unit is displayed in real time.

As such, the technical configuration of the present invention described above can be understood by those skilled in the art that the present invention can be implemented in other specific forms without changing the technical spirit or essential features of the present invention.

Therefore, the above-described embodiments are to be understood as illustrative and not restrictive in all respects, and the scope of the present invention is indicated by the following claims rather than the detailed description, and the meaning and scope of the claims and their All changes or modifications derived from equivalent concepts should be construed as being included in the scope of the present invention.

According to the computer-readable medium recording the crack monitoring system, the crack monitoring method, and the crack monitoring program according to the present invention, the crack position can be monitored in real time as the test proceeds, so that the bacteria can be easily and conveniently identified in real time. can do. Moreover, according to the computer-readable medium which recorded the crack monitoring system, the crack monitoring method, and the crack monitoring program which concerns on this invention, since only a simple measuring apparatus is needed, the cost input for crack location can be reduced.

1 is a view for explaining a crack monitoring system according to an embodiment of the present invention.

2 is a photograph showing that the accelerometer is installed on the actual test body.

3 is a photograph showing that the microphone is installed around the actual test specimen.

4 schematically illustrates a crack location tracking algorithm.

5 is a diagram capturing a screen displayed on the display unit 150 during the simulation test.

6 is a diagram capturing a screen displayed on the display unit 150 when the test is completed.

7 is a crack information table displayed on the display unit 150.

8 is a signal processing flowchart according to the present invention.

***** Explanation of symbols for main parts of drawing *****

100: printout map display device

110: detector

111: handle

120: recording unit

130: detection position recognition unit

140: factor map data generation unit

150: display unit

160: target unit

Claims (6)

It is a crack monitoring system that monitors cracks occurring in the test specimen under load, A plurality of acceleration sensing units installed in the test object to sense acceleration; A plurality of noise detectors installed around the test object to detect noise; The time at which the crack occurs as determined from the acceleration signals detected by the plurality of acceleration detectors, the time at which the noise due to the crack detected from the noise signals detected by the plurality of noise detectors is detected, and the plurality of noises A crack position tracking unit for tracking the position of the crack using a relative position from the test body of the sensing unit, and A display unit which displays the crack position tracked by the crack position tracking unit in real time; Crack monitoring system comprising a. The method of claim 1, The display unit displays the tracked crack location in real time on a two-dimensional drawing or 3D cad data of the test object, Crack monitoring system. The method of claim 1, The crack monitoring system further comprises an image photographing unit for photographing the front, plane, right side of the test body, The display unit displays the tracked crack position in real time on the front image, the planar image, and the right side image of the test object being photographed by the image photographing unit. Crack monitoring system. The method according to any one of claims 1 to 3, The display unit displays the load applied to the test body in real time, Crack monitoring system. It is a crack monitoring method for monitoring cracks occurring in the test specimen under load, An acceleration sensing step of sensing acceleration by a plurality of acceleration sensing units installed in the test body, Noise detection step of detecting the noise by a plurality of noise detection unit installed around the test body, The time at which the crack occurs as determined from the acceleration signals detected by the plurality of acceleration detectors, the time at which the noise due to the crack detected from the noise signals detected by the plurality of noise detectors is detected, and the plurality of noises A crack position tracking step of tracking the position of the crack using the relative position from the test body of the sensing unit, and A display step of displaying the crack location tracked in the crack location tracking step in real time; Crack monitoring method comprising a. A computer readable medium that records a crack monitoring program that monitors cracks occurring in a specimen under load. An acceleration sensing step of sensing acceleration by a plurality of acceleration sensing units installed in the test body, Noise detection step of detecting the noise by a plurality of noise detection unit installed around the test body, The time at which the crack occurs as determined from the acceleration signals detected by the plurality of acceleration detectors, the time at which the noise due to the crack detected from the noise signals detected by the plurality of noise detectors is detected, and the plurality of noises A crack position tracking step of tracking the position of the crack using the relative position from the test body of the sensing unit, and A display step of displaying the crack location tracked in the crack location tracking step in real time; A computer readable medium having recorded a crack monitoring program for executing the program.

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