Title of the invention: Optical fiber sensing system, optical fiber sensing device, and piping deterioration detection method
Technical field
[0001]
This disclosure relates to an optical fiber sensing system, an optical fiber sensing device, and a piping deterioration detection method.
Background technology
[0002]
Conventionally, the inspection work of the piping laid in the plant etc. was often carried out manually by skilled workers. However, in the case of such inspection work, it is necessary to dispatch a skilled worker to the piping every time the inspection work is performed, which is costly. In addition, it was necessary to prepare the environment for the workers to perform the inspection work. As an environmental preparation, for example, if the pipes are placed on the ground, it is necessary to construct a scaffold, and if the pipes are placed underground, excavation is required. Preparing such an environment was not only costly but also time consuming.
[0003]
Therefore, recently, a technique for detecting the state of piping has been proposed regardless of the worker. For example, Patent Document 1 describes a plurality of locations on the surface of an external pipe in a high-temperature gas pipe composed of an internal pipe through which a high-temperature fluid flows, a heat insulating material layer covering the internal pipe, and an external pipe covering the heat insulating material layer. Disclosed is a technique for detecting an abnormal situation caused by damage to a heat insulating material from the measured temperature distribution data on the surface of an external pipe.
Prior art literature
Patent documents
[0004]
Patent Document 1: Japanese Patent Application Laid-Open No. 10-207534
Outline of the invention
Problems to be solved by the invention
[0005]
However, in the technique disclosed in Patent Document 1, since the temperature distribution on the surface of the external pipe covering the heat insulating material is used to detect an abnormal situation, the substance flowing through the pipe is hot and the pipe is heat-insulated. It can only be handled when materials are used.
In other words, the technique disclosed in Patent Document 1 has a problem that it cannot be used when the substance flowing through the pipe is not at a high temperature or when the pipe does not use a heat insulating material.
[0006]
Therefore, an object of the present disclosure is an optical fiber sensing system, an optical fiber sensing device, and a pipe deterioration capable of solving the above-mentioned problems and detecting the state of the pipe without depending on the substance flowing through the pipe or the structure of the pipe. The purpose is to provide a detection method.
Means to solve problems
[0007]
The optical fiber sensing system according to one aspect is
The optical fiber laid in the piping and
A receiving unit that receives an optical signal on which the vibration detected by the optical fiber is superimposed from the optical fiber.
A determination unit that extracts the vibration pattern of the vibration detected by the optical fiber from the optical signal and determines the deterioration state of the pipe based on the extracted vibration pattern.
Equipped with.
[0008]
The optical fiber sensing device according to one aspect is
A receiving unit that receives an optical signal on which vibration detected by the optical fiber is superimposed from an optical fiber laid in a pipe.
A determination unit that extracts the vibration pattern of the vibration detected by the optical fiber from the optical signal and determines the deterioration state of the pipe based on the extracted vibration pattern.
Equipped with.
[0009]
The piping deterioration detection method according to one aspect is
The step that the optical fiber laid in the piping detects vibration,
A reception step of receiving an optical signal on which the vibration detected by the optical fiber is superimposed from the optical fiber,
A determination step of extracting a vibration pattern of vibration detected by the optical fiber from the optical signal and determining a deterioration state of the pipe based on the extracted vibration pattern.
including.
The invention's effect
[0010]
According to the above-described aspect, it is possible to provide an optical fiber sensing system, an optical fiber sensing device, and a pipe deterioration detection method that can detect the state of the pipe without depending on the substance flowing through the pipe or the structure of the pipe. ..
A brief description of the drawing
[0011]
FIG. 1 is a diagram showing a configuration example of an optical fiber sensing system according to a first embodiment.
FIG. 2 is a diagram showing another configuration example of the optical fiber sensing system according to the first embodiment.
FIG. 3 is a diagram showing another configuration example of the optical fiber sensing system according to the first embodiment.
FIG. 4 is a diagram showing another configuration example of the optical fiber sensing system according to the first embodiment.
FIG. 5 is a flow chart showing an example of machine learning executed by the determination unit according to the first embodiment.
FIG. 6 is a diagram showing an example of teacher data used for machine learning executed by the determination unit according to the first embodiment.
FIG. 7 is a diagram showing an example of a vibration pattern extracted by the determination unit according to the first embodiment.
FIG. 8 is a diagram showing an example of a vibration pattern extracted by the determination unit according to the first embodiment.
FIG. 9 is a diagram showing an example of a vibration pattern extracted by the determination unit according to the first embodiment.
FIG. 10 is a diagram showing an example of a vibration pattern extracted by the determination unit according to the first embodiment.
FIG. 11 is a diagram showing an example of a vibration pattern extracted by the determination unit according to the first embodiment.
[Fig. 12] Fig. 12 is a diagram showing an example of a situation in which elastic waves are generated due to corrosion of pipes.
FIG. 13 is a diagram showing an example of a vibration pattern extracted by the determination unit according to the first embodiment.
FIG. 14 is a diagram showing an example of a vibration pattern extracted by the determination unit according to the first embodiment.
FIG. 15 is a diagram showing an example of a vibration pattern extracted by the determination unit according to the first embodiment.
FIG. 16 is a flow chart showing an operation example of the optical fiber sensing system according to the first embodiment.
FIG. 17 is a diagram showing an example of a correspondence table stored by the determination unit according to the second embodiment.
FIG. 18 is a diagram showing an example in which vibration patterns extracted by the determination unit according to the second embodiment are arranged in chronological order.
FIG. 19 is a flow chart showing an operation example of the optical fiber sensing system according to the second embodiment.
[Fig. 20] Fig. 20 is a diagram showing an example of a surplus of an optical fiber.
FIG. 21 is a diagram showing an example of a correspondence table stored by the determination unit according to the third embodiment.
FIG. 22 is a diagram showing an example of a method of specifying the length of an optical fiber from a receiving unit to a position where vibration is generated in the determination unit according to the third embodiment.
FIG. 23 is a flow chart showing an operation example of the optical fiber sensing system according to the third embodiment.
FIG. 24 is a flow chart showing another operation example of the optical fiber sensing system according to the third embodiment.
FIG. 25 is a diagram showing a modified example of the optical fiber sensing system according to the third embodiment.
FIG. 26 is a diagram showing a configuration example of an optical fiber sensing system according to a fourth embodiment.
FIG. 27 is a diagram showing an example of a GUI screen used for notification by the notification unit according to the fourth embodiment.
FIG. 28 is a flow chart showing an operation example of the optical fiber sensing system according to the fourth embodiment.
FIG. 29 is a block diagram showing an example of a hardware configuration of a computer that realizes an optical fiber sensing device according to an embodiment.
Embodiment for carrying out the invention
[0012]
Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The following descriptions and drawings have been omitted or simplified as appropriate for the sake of clarification of the explanation. Further, in each of the following drawings, the same elements are designated by the same reference numerals, and duplicate explanations are omitted as necessary.
[0013]

First, a configuration example of the optical fiber sensing system according to the first embodiment will be described with reference to FIG. 1.
[0014]
As shown in FIG. 1, the optical fiber sensing system according to the first embodiment includes an optical fiber 10 and an optical fiber sensing device 20. Further, the optical fiber sensing device 20 includes a receiving unit 21 and a determining unit 22.
[0015]
The optical fiber 10 is laid in the pipe 30 and one end thereof is connected to the optical fiber sensing device 20. FIG. 1 shows an example in which the optical fiber 10 is passed through the inside of the pipe 30, but the method of laying the optical fiber 10 is not limited to this. For example, the optical fiber 10 may be wound around the pipe 30, or may crawl inside or outside the pipe 30 along the pipe 30. Further, a sheet in which the optical fiber 10 is woven may be wound around the pipe 30. Further, the optical fiber 10 may be housed together with other cables in a box arranged inside or outside the pipe 30 along the pipe 30.
[0016]
Further, the pipe 30 may be laid in any place such as above ground, underground, ceiling, floor, wall, etc. FIG. 2 shows an example of laying the pipe 30 on the ground. In the example of FIG. 2, the pipe 30 is supported by pillars 31A to 31C (hereinafter, referred to as pillars 31 when the pillars 31A to 31C are not specified) and is laid on the ground. Further, FIG. 3 shows an example of laying the pipe 30 underground.
[0017]
More specifically, the pipe 30 is a cable laid underground, a pipe for sewage, an air conditioning pipe laid on the ceiling, a pipe for a high-temperature fluid used in a plant, and the like. Applications are not limited to these applications.
[0018]
Further, the optical fiber 10 is not limited to one, and a plurality of optical fibers may be provided. FIG. 4 shows an example in which two optical fibers 10 are laid in the pipe 30. In the example of FIG. 4, one end of each of the two optical fibers 10 is connected to the optical fiber sensing device 20, and the two optical fibers 10 extend in opposite directions to each other.
[0019]
The receiving unit 21 incidents pulsed light on the optical fiber 10. Further, the receiving unit 21 receives the reflected light or scattered light generated when the pulsed light is transmitted through the optical fiber 10 as return light (optical signal) via the optical fiber 10.
[0020]
When vibration is generated in the pipe 30, the vibration is transmitted to the optical fiber 10 laid in the pipe 30 and superimposed on the return light transmitted by the optical fiber 10. Therefore, the optical fiber 10 can detect the vibration generated in the pipe 30.
[0021]
Therefore, when vibration is generated in the pipe 30, the optical fiber 10 detects the vibration and superimposes it on the return light for transmission, and the receiving unit 21 receives the return light on which the vibration detected by the optical fiber 10 is superimposed. Will be done.
[0022]
Here, the vibration generated in the pipe 30 has a unique vibration pattern in which the strength of the vibration, the vibration position, the transition of the fluctuation of the frequency, and the like differ depending on the deterioration state of the pipe 30. Therefore, it is possible to determine the deterioration state of the pipe 30 by analyzing the dynamic change of the vibration pattern of the vibration generated in the pipe 30.
[0023]
Therefore, the determination unit 22 extracts the vibration pattern of the vibration detected by the optical fiber 10 from the return light received by the reception unit 21 from the optical fiber 10, and determines the deterioration state of the pipe 30 based on the extracted vibration pattern. do. In other words, the determination unit 22 determines how much the pipe 30 has deteriorated.
[0024]
In the present specification, the breakage of the pipe 30 means a state in which a substance flowing through the pipe 30 leaks (for example, a crack or the like), and the deterioration of the pipe 30 means a state in the middle of the breakage (for example, for example). Corrosion, wear, etc.).
[0025]
Here, an example of a method of determining the deterioration state of the pipe 30 based on the vibration pattern of the vibration detected by the optical fiber 10 in the determination unit 22 will be described.
[0026]
(A1) Method A1
First, method A1 will be described.
In method A, the determination unit 22 uses pattern matching.
[0027]
For example, the determination unit 22 stores in advance the vibration pattern when vibration occurs in the pipe 30 with the degree of deterioration for each degree of deterioration of the pipe 30 as a matching pattern. The determination unit 22 compares the vibration pattern detected by the optical fiber 10 with the matching pattern stored in advance. When the vibration pattern detected by the optical fiber 10 matches any of the matching patterns stored in advance, the determination unit 22 determines that the pipe 30 has a degree of deterioration corresponding to the matched matching pattern.
[0028]
Further, the determination unit 22 may change the matching pattern according to the environment in which the pipe 30 is laid and the substance flowing through the pipe 30.
example For example, when the pipe 30 is laid outdoors, the determination unit 22 may use a vibration pattern of vibration generated by wind or rain as a matching pattern, or depending on a train or a car traveling on a surrounding road. The vibration pattern of the generated vibration may be used, or the vibration pattern of the vibration generated by the vibration of frequent construction work may be used.
[0029]
Further, the substance flowing through the pipe 30 is roughly classified into a liquid, a gas, or a solid. Therefore, the determination unit 22 may change the matching pattern depending on whether the substance flowing through the pipe 30 is a liquid, a gas, or a solid.
[0030]
(A2) Method A2
Next, method A2 will be described.
In the method A2, the determination unit 22 machine-learns (for example, deep learning) a vibration pattern according to the deterioration state of the pipe 30, and uses the learning result of the machine learning (initial learning model) to deteriorate the pipe 30. Judge the condition.
[0031]
Here, the machine learning method in the method A2 will be described with reference to FIG.
As shown in FIG. 5, the determination unit 22 inputs the teacher data indicating the degree of deterioration of the pipe 30 and the vibration pattern of the vibration generated in the pipe 30 with the degree of deterioration and detected by the optical fiber 10 (step). S11, S12). FIG. 6 shows an example of teacher data. FIG. 6 is an example of teacher data in the case of learning the three vibration patterns A, B, and C. In addition, in FIG. 6, in the normal pipe 30, the degree of deterioration is 0, and the larger the numerical value of the degree of deterioration is, the more the deterioration is progressing (the same applies to FIGS. 17 and 18 below).
[0032]
Subsequently, the determination unit 22 performs matching and classification of the two (step S13), and performs supervised learning (step S14). As a result, an initial learning model is obtained (step S15). This initial learning model is a model in which the degree of deterioration of the pipe 30 is output when the vibration pattern of the vibration detected by the optical fiber 10 is input.
[0033]
When determining the deterioration state of the pipe 30, the determination unit 22 inputs the vibration pattern of the vibration detected by the optical fiber 10 into the initial learning model. As a result, the determination unit 22 obtains the degree of deterioration of the pipe 30 as the output result of the initial learning model.
[0034]
Further, the determination unit 22 may change the initial learning model according to the environment in which the pipe 30 is laid and the substance flowing through the pipe 30. Examples of the environment in which the pipe 30 is laid and the substance flowing through the pipe 30 are as described in the above-mentioned method A1.
[0035]
(A3) Method A3
Next, method A3 will be described.
FIG. 7 shows a vibration pattern of the vibration detected at a certain position on the optical fiber 10 when an artificial vibration is generated in the pipe 30, where the horizontal axis represents time and the vertical axis represents vibration intensity. Shows.
8 and 9 schematically show a vibration pattern as shown in FIG. 7, and the horizontal axis and the vertical axis of FIGS. 8 and 9 are the same as those of FIG. 7.
[0036]
In the vibration patterns shown in FIGS. 8 and 9, when vibration occurs, the vibration is subsequently attenuated. This damping time varies depending on the deterioration state of the pipe 30. Specifically, when the pipe 30 is in a normal state, the damping time is short, but as the deterioration of the pipe 30 progresses, the damping time becomes longer.
[0037]
Therefore, in the method A3, the determination unit 22 determines the deterioration state of the pipe 30 based on the length of the damping time in the vibration pattern of the vibration detected by the optical fiber 10.
[0038]
(A4) Method A4
Next, the method A4 will be described.
FIGS. 10 and 11 schematically show a vibration pattern after FFT (Fast Fourier Transform) a vibration pattern as shown in FIG. 7 when an artificial vibration is generated in the pipe 30. The axis shows the frequency and the vertical axis shows the vibration intensity.
[0039]
In the vibration patterns shown in FIGS. 10 and 11, a frequency peak of vibration intensity occurs. The frequency at which this frequency peak occurs differs depending on the deterioration state of the pipe 30. Specifically, in the vibration pattern of the deteriorated pipe 30, the frequency at which the frequency peak occurs shifts to the higher frequency side than the vibration pattern of the normal pipe 30.
[0040]
Therefore, in the method A4, the determination unit 22 determines the deterioration state of the pipe 30 based on the frequency at which the frequency peak occurs in the vibration pattern of the vibration detected by the optical fiber 10.
[0041]
(A5) Method A5
Next, method A5 will be described.
FIG. 12 shows the situation when the pipe 30 is corroded. Further, FIG. 13 shows the same vibration pattern as in FIGS. 10 and 11 when the pipe 30 is corroded.
[0042]
As shown in FIG. 12, when corrosion occurs in the pipe 30, elastic waves are generated.
As shown in FIG. 13, the vibration caused by the elastic wave has different vibration characteristics from the vibration that is constantly generated due to the flow of a substance through the pipe 30 or the like. Specifically, the vibration that is constantly generated in the pipe 30 is generated in the low frequency band. On the other hand, the vibration caused by the elastic wave generated by the corrosion of the pipe 30 is generated in the high frequency band.
[0043]
Therefore, in the method A5, the determination unit 22 determines the deterioration state of the pipe 30 based on whether or not the vibration due to the elastic wave is generated in the high frequency band in the vibration pattern of the vibration detected by the optical fiber 10. ..
[0044]
(A6) Method A6
Next, method A6 will be described.
14 and 15 show the same vibration pattern as in FIGS. 8 and 9 when the pipe 30 is corroded.
[0045]
In the vibration patterns shown in FIGS. 14 and 15, vibration due to elastic waves generated by corrosion of the pipe 30 is generated. The interval at which this vibration occurs varies depending on the degree of corrosion of the pipe 30. Specifically, in the vibration pattern of the pipe 30 in which the progress of corrosion is slight, the frequency of vibration due to elastic waves per unit time is low. On the other hand, in the vibration pattern of the pipe 30 in which the progress of corrosion is severe, the frequency of vibration due to elastic waves per unit time is high.
[0046]
Therefore, in the method A6, the determination unit 22 determines the deterioration state of the pipe 30 based on the frequency of occurrence of vibration due to elastic waves in the vibration pattern of the vibration detected by the optical fiber 10.
[0047]
Subsequently, with reference to FIG. 16, an operation example of the optical fiber sensing system according to the first embodiment will be described.
As shown in FIG. 16, the optical fiber 10 detects the vibration generated in the pipe 30 (step S21). The vibration detected by the optical fiber 10 is superimposed on the return light transmitted through the optical fiber 10.
Subsequently, the receiving unit 21 receives from the optical fiber 10 the return light on which the vibration detected by the optical fiber 10 is superimposed (step S22).
[0048]
Subsequently, the determination unit 22 extracts the vibration pattern of the vibration detected by the optical fiber 10 from the return light received by the reception unit 21, and determines the deterioration state of the pipe 30 based on the extracted vibration pattern (step). S23). This determination may be performed, for example, by using any of the above-mentioned methods A1 to A5.
[0049]
As described above, according to the first embodiment, the receiving unit 21 receives the return light on which the vibration detected by the optical fiber 10 is superimposed from the optical fiber 10 laid in the pipe 30. The determination unit 22 extracts the vibration pattern of the vibration detected by the optical fiber 10 from the return light, and determines the deterioration state of the pipe 30 based on the extracted vibration pattern.
[0050]
At this time, it is sufficient that the optical fiber 10 is laid in the pipe 30, and the substance flowing through the pipe 30 does not need to be at a high temperature as in Patent Document 1, and the pipe 30 does not need to be covered with a heat insulating material. Therefore, the deterioration state of the pipe 30 can be detected without depending on the substance flowing through the pipe 30 or the structure of the pipe 30.
[0051]

The optical fiber sensing system according to the second embodiment has the same configuration as that of the first embodiment described above, but has an expanded function of the determination unit 22.
The determination unit 22 determines the deterioration state of the pipe 30 based on the vibration pattern of the vibration detected by the optical fiber 10, and further detects a sign of damage to the pipe 30 based on the determined deterioration state of the pipe 30. ..
[0052]
Here, an example of a method in which the determination unit 22 detects a sign of damage to the pipe 30 based on the deterioration state of the pipe 30 will be described.
[0053]
(B1) Method B1
First, method B1 will be described.
In the method B1, as shown in FIG. 17, the determination unit 22 indicates, for each degree of deterioration of the pipe 30, a corresponding table showing the damage time, which is the time when the pipe 30 with the degree of deterioration is predicted to be damaged in the future. Is memorized in advance.
[0054]
First, the determination unit 22 determines the deterioration state (here, the degree of deterioration) of the pipe 30 by using any one of the above-mentioned methods A1 to A5, and determines the degree of deterioration of the pipe 30 and the corresponding table shown in FIG. Based on the above, a sign of damage to the pipe 30 is detected. For example, the determination unit 22 determines that the pipe 30 having a deterioration degree of 2 has a sign of damage and the time of damage is two years later.
[0055]
(B2) Method B2
Next, method B2 will be described.
In the method B2, the determination unit 22 periodically (for example, every year) determines the deterioration state of the pipe 30 by using any of the above-mentioned methods A1 to A5, and periodically determines the pipe. 30 deterioration states are stored. Then, the determination unit 22 detects a sign of damage to the pipe 30 based on a change in the state of deterioration of the pipe 30 over time.
[0056]
FIG. 18 is a diagram for explaining method B2. Note that FIG. 18 is an example in which the determination unit 22 determines the deterioration state of the pipe 30 by using the above-mentioned method A5, and the same vibration patterns as those in FIGS. 10 and 11 are shown in time series. It is a thing.
[0057]
In the example of FIG. 18, the determination unit 22 periodically (here, every year) determines the deterioration state of the pipe 30. Here, the determination unit 22 determines that the pipe 30 was normal two years ago, but has a deterioration degree of 1 one year ago and a deterioration degree of two at present.
[0058]
The determination unit 22 determines the vibration pattern one year later, the frequency at which the frequency peak occurs in the vibration pattern, and the frequency at which the frequency peak occurs, based on the changes over time in the vibration patterns of the pipe 30 two years ago, one year ago, and the current pipe 30. Predict. In the example of FIG. 18, as a result of prediction, the frequency at which the frequency peak occurs in the vibration pattern one year later is located on the high frequency side of the threshold value. Therefore, the determination unit 22 determines that the pipe 30 will be damaged after one year.
[0059]
Subsequently, with reference to FIG. 19, an operation example of the optical fiber sensing system according to the second embodiment will be described.
As shown in FIG. 19, first, steps S31 to S33 similar to steps S21 to S23 shown in FIG. 16 are performed.
Subsequently, the determination unit 22 detects a sign of damage to the pipe 30 based on the deterioration state of the pipe 30 determined in step S33 (step S34). This detection may be performed, for example, by using any of the above-mentioned methods B1 and B2.
[0060]
As described above, according to the second embodiment, the determination unit 22 detects a sign of damage to the pipe 30 based on the deterioration state of the pipe 30.
As a result, before the pipe 30 is damaged and a problem such as leakage of a substance flowing through the pipe 30 occurs, a worker can be dispatched to repair the pipe 30.
Other effects are the same as those in the first embodiment described above.
[0061]

The optical fiber sensing system according to the third embodiment has the same configuration as that of the second embodiment described above, but further expands the function of the determination unit 22.
The determination unit 22 identifies the position where the sign of damage to the pipe 30 is detected based on the return light received by the reception unit 21.
[0062]
Here, an example of a method of specifying a position in the determination unit 22 where a sign of damage to the pipe 30 is detected based on the return light received by the reception unit 21 will be described.
[0063]
(C1) Law C1
First, method C1 will be described.
In the method C1, first, the determination unit 22 is based on the time difference between the time when the receiving unit 21 incidents the pulsed light on the optical fiber 10 and the time when the receiving unit 21 receives the return light on which the vibration is superimposed. , The length of the optical fiber 10 from the receiving unit 21 (optical fiber sensing device 20) to the position where the vibration is generated is specified. Let the length of the optical fiber 10 specified here be X [m].
[0064]
Further, when the optical fiber 10 is laid in the pipe 30, a surplus may be generated as shown in FIG. 20. Let the length of this surplus be Y [m]. It is assumed that the determination unit 22 has grasped the surplus length Y [m] in advance.
[0065]
Then, the determination unit 22 specifies the distance Z [m] from the reception unit 21 to the position where the vibration is generated by the following mathematical formula (1) using the above-mentioned X and Y.
Z [m] = X [m] -Y [m] ... (1)
[0066]
Further, the determination unit 22 stores in advance a correspondence table in which the distance from the reception unit 21 and the location corresponding to the distance are associated with each other. This makes it possible to specify the position (location) where the vibration occurs. Here, as shown in FIG. 2, FIG. 21 shows an example of a corresponding table in the case where the pipe 30 is supported by the pillar 31 and laid on the ground. In the example of FIG. 21, the distance from the receiving unit 21 and the identification information of the pillar 31 installed at the position corresponding to the distance are associated with each other. For example, when the distance Z [m] from the receiving unit 21 to the position where the vibration is generated is xx [m], the determination unit 22 determines that the place where the vibration is generated is the place where the pillar 31A is located. .. The correspondence table in FIG. 21 was a table in which the distance from the receiving unit 21 and the identification information of the pillar 31 were associated with each other, but the identification information associated with the distance is not limited to the pillar 31 and identifies the location. Any information may be used, and for example, information for identifying an area may be used.
[0067]
When the determination unit 22 specifies the position where the sign of damage to the pipe 30 is detected, the determination unit 22 specifies the position where the vibration of the vibration pattern used for detecting the sign of damage to the pipe 30 occurs as described above. Then, the determination unit 22 sets the specified position as a position where a sign of damage to the pipe 30 is detected.
[0068]
Note that the determination unit 22 may specify the position where the sign of damage is detected when the sign of damage to the pipe 30 is detected. Alternatively, the determination unit 22 specifies in advance the position where the vibration is generated when the receiving unit 21 receives the return light on which the vibration is superimposed, and then uses the vibration pattern of the vibration. When a sign of damage to the pipe 30 is detected, the position specified in advance may be set as the position where the sign of damage to the pipe 30 is detected.
[0069]
(C2) Method C2
Next, method C2 will be described. The method C2 is different from the method C1 in the method of specifying the length X [m] of the optical fiber 10 from the receiving unit 21 to the position where the vibration is generated, but is the same as the method C1 except for the method C1.
[0070]
In the method C2, the determination unit 22 compares the intensity of the vibration detected at the position corresponding to the length of each length of the optical fiber 10 from the reception unit 21, and receives based on the comparison result. The length X [m] of the optical fiber 10 from the portion 21 to the position where the vibration is generated is specified.
[0071]
For example, as shown in FIG. 22, it is assumed that vibration is detected for each length of the optical fiber 10 from the receiving unit 21. In the example of FIG. 22, the intensity of vibration is indicated by the size of a circle, and the larger the size of the circle, the greater the intensity of vibration. In this case, the determination unit 22 identifies the position where the vibration is generated according to the distribution of the vibration intensity. In the example of FIG. 22, since the vibration intensity is large in the vicinity of the pillar 31A, the determination unit 22 specifies the length X [m] of the optical fiber 10 from the receiving unit 21 to the vicinity of the pillar 31A. ..
[0072]
Subsequently, with reference to FIG. 23, an operation example of the optical fiber sensing system according to the third embodiment will be described. FIG. 23 is an example of specifying the position where the sign of breakage is detected at the time when the sign of breakage of the pipe 30 is detected.
[0073]
As shown in FIG. 23, first, steps S41 to S44 similar to steps S31 to S34 shown in FIG. 19 are performed.
When a sign of damage to the pipe 30 is detected in step S44 (Yes in step S45), the determination unit 22 subsequently detects a position where the sign of damage to the pipe 30 is detected based on the return light received by the receiving unit 21. (Step S46). This specification may be performed by using, for example, either the above-mentioned method C1 or C2.
[0074]
Subsequently, with reference to FIG. 24, another operation example of the optical fiber sensing system according to the third embodiment will be described. In FIG. 24, when the receiving unit 21 receives the return light on which the vibration is superimposed, the position where the vibration is generated is specified in advance, and the position specified in advance is the position where the sign of damage to the pipe 30 is detected. This is an example of
[0075]
As shown in FIG. 24, first, steps S51 to S52 similar to steps S31 to S32 shown in FIG. 19 are performed.
Subsequently, the determination unit 22 identifies the position where the vibration superimposed on the return light is generated based on the return light received by the reception unit 21 (step S53). This specification may be performed by using, for example, either the above-mentioned method C1 or C2.
[0076]
Subsequently, steps S54 to S55 similar to steps S33 to S34 shown in FIG. 19 are performed.
When the sign of damage to the pipe 30 is detected in step S55 (Yes in step S56), the determination unit 22 subsequently identifies the position previously specified in step S53 as the position where the sign of damage to the pipe 30 is detected. (Step S57).
[0077]
As described above, according to the third embodiment, the determination unit 22 detects a sign of damage to the pipe 30 based on the deterioration state of the pipe 30, and also based on the return light received by the receiving unit 21. The position where the sign of the breakage of the pipe 30 is detected is specified.
[0078]
As a result, before the pipe 30 is damaged and a problem such as leakage of a substance flowing through the pipe 30 occurs, a worker can be dispatched to repair the pipe 30. Further, since the position where the sign of damage of the pipe 30 is detected can be specified, for example, even when the pipe 30 is laid over a wide area, the position where the sign of damage is detected can be accurately grasped and the worker Can be dispatched.
Other effects are the same as those in the first embodiment described above.
[0079]
Here, a modified example of the third embodiment will be described with reference to FIG. 25.
As shown in FIG. 25, in this modification, the determination unit 22 is detected at a plurality of points in the section on the optical fiber 10 in which the material of the pipe 30 is the same and the substance flowing through the pipe 30 is the same. Extract the vibration pattern of the vibration.
[0080] [0080]
Then, the determination unit 22 compares the vibration patterns detected at a plurality of points, and identifies the position where deterioration has occurred or the position where there is a sign of damage based on the comparison result.
For example, when the vibration pattern detected at some points is different from the vibration pattern detected at other points, the determination unit 22 deteriorates at some points where different vibration patterns are detected. It is judged that there is a sign of damage or there is a sign of damage.
At this time, the determination unit 22 may determine whether or not the vibration pattern detected at some points is different from the vibration pattern detected at other points, for example, as follows. First, the determination unit 22 identifies the range of the normal vibration pattern based on the distribution, average, or the like of the vibration patterns detected at a plurality of points. Then, the determination unit 22 determines that, among the vibration patterns detected at the plurality of points, the vibration pattern outside the range of the normal vibration pattern is different from the vibration pattern detected at the other points.
[0081]
For example, in the example of FIG. 25, the determination unit 22 extracts the vibration pattern as shown in FIGS. 10 and 11 as the vibration pattern of the vibration detected at a plurality of points, and the frequency peak is generated between the vibration patterns. The generated frequencies are compared. As a result, in the vibration pattern detected at the point X, the frequency at which the frequency peak occurs is shifted to the high frequency side as compared with the vibration pattern detected at the other points in the section Y. Therefore, the determination unit 22 determines that deterioration has occurred at the point X or that there is a sign of damage. The position of the point X may be specified by using, for example, either the above-mentioned method C1 or C2.
[0082]
In the example of FIG. 25, the vibration pattern as shown in FIGS. 10 and 11 was extracted, but the present invention is not limited to this, and other vibration patterns may be extracted.
[0083]

Subsequently, with reference to FIG. 26, a configuration example of the optical fiber sensing system according to the fourth embodiment will be described.
[0084]
As shown in FIG. 26, the optical fiber sensing system according to the fourth embodiment has an additional display unit 40 as compared with the configurations of the first to third embodiments described above, and the optical fiber sensing. The difference is that the notification unit 23 is added to the device 20.
[0085]
The notification unit 23 notifies an alert when the determination unit 22 detects a sign of damage to the pipe 30. At this time, the notification unit 23 may notify the position where the sign of damage to the pipe 30 is detected. The notification destination may be, for example, a monitoring system for monitoring the pipe 30, a monitoring terminal in a monitoring room for monitoring the pipe 30, or a user terminal. Further, the notification method may be, for example, a method of displaying a GUI (Graphical User Interface) screen on a display unit 40 such as a display or a monitor of a notification destination. Further, the notification method may be a method of outputting a message by voice from a speaker (not shown) of the notification destination.
[0086]
Further, the notification unit 23 may store the information indicating the position where the optical fiber 10 laid in the pipe 30 is laid and the map information in association with each other. Then, when the determination unit 22 detects a sign of damage to the pipe 30, the notification unit 23 may map and display the position where the sign of damage to the pipe 30 is detected on the map displayed by the display unit 40. good. FIG. 27 shows an example of a GUI screen that maps and displays a position where a sign of damage to the pipe 30 is detected on a map. In the example of FIG. 27, the position where the optical fiber 10 is laid is mapped and displayed on the map, and the position X where the sign of the breakage of the pipe 30 is detected is mapped and displayed. At this time, the notification unit 23 may display the current deterioration state at the position where the sign of damage to the pipe 30 is detected. The map shown in FIG. 27 can be enlarged or reduced as needed.
[0087]
Subsequently, with reference to FIG. 28, an operation example of the optical fiber sensing system according to the fourth embodiment will be described.
As shown in FIG. 28, first, steps S61 to S66 similar to steps S41 to S46 in FIG. 23 are performed.
[0088]
When the determination unit 22 detects a sign of damage to the pipe 30 in step S64 (Yes in step S65) and identifies a position where the sign of damage to the pipe 30 is detected (step S66), the notification unit 23 subsequently detects the sign of damage to the pipe 30. , Notify an alert (step S67). This notification may be performed, for example, by using the GUI screen shown in FIG. 27 described above.
[0089]
Note that the operation example shown in FIG. 28 is an example, and is not limited to this. The operation example shown in FIG. 28 may be modified, for example, by adding step S67 shown in FIG. 28 to the operation example as shown in FIG. 24.
[0090]
Further, in the example of FIG. 28, the notification unit 23 notifies the alert only when it detects a sign of damage to the pipe 30, but the present invention is not limited to this. For example, the notification unit 23 may notify an alert when the deterioration degree is equal to or higher than the threshold value as a result of determining the deterioration state of the pipe 30, and determines the deterioration state of the pipe 30 regardless of the deterioration degree. You may notify. Further, in the notification unit 23, the display unit 40 is the same as in FIG. 27.On the map to be displayed, a position where the degree of deterioration of the pipe 30 is equal to or higher than the threshold value or a position where the deterioration state of the pipe 30 is determined may be mapped and displayed.
[0091]
As described above, according to the fourth embodiment, when the determination unit 22 detects a sign of damage to the pipe 30, the notification unit 23 notifies the alert. As a result, it is possible to notify the monitoring system, the monitoring room, or the like that monitors the pipe 30 that a sign of damage to the pipe 30 has been detected.
Other effects are the same as those in the first embodiment described above.
[0092]

In the above-described embodiment, the determination unit 22 determines the deterioration state of the pipe 30 based on the vibration pattern of the vibration detected by the optical fiber 10. The determination unit 22 may determine the deterioration state of the pipe 30 by further adding the pipe information stored in advance for the pipe 30. The piping information includes, for example, the material and thickness of the piping 30, the type of substance flowing through the piping 30, the flow rate of the substance flowing through the piping 30, and the like. As a result, the determination accuracy can be improved. In order to take into account the piping information, for example, when the above-mentioned method A1 is used for determining the deterioration state of the piping 30, it is conceivable to change the matching pattern according to the piping information. Further, when the above-mentioned method A2 is used for determining the deterioration state of the pipe 30, it is conceivable to change the learning model according to the pipe information.
[0093]
Further, the determination unit 22 may determine the type and flow rate of the substance flowing through the piping 30 in the above-mentioned piping information based on the vibration pattern of the vibration detected by the optical fiber 10. As the determination method, a method of using pattern matching as in the above-mentioned method A1 and a method of using a learning model as in the above-mentioned method A2 can be considered. Further, the optical fiber 10 can detect not only vibration but also sound and temperature. Therefore, the determination unit 22 may determine the type of the substance flowing through the pipe 30 by using at least one of the vibration, the sound, and the temperature detected by the optical fiber 10.
[0094]
Further, in the above-described embodiment, the optical fiber sensing device 20 is provided with a plurality of components (reception unit 21, determination unit 22, and notification unit 23), but the present invention is not limited to this. The components provided in the optical fiber sensing device 20 are not limited to being provided in one device, and may be distributed in a plurality of devices.
[0095]

Subsequently, with reference to FIG. 29, the hardware configuration of the computer 50 that realizes the optical fiber sensing device 20 will be described.
[0096]
As shown in FIG. 29, the computer 50 includes a processor 501, a memory 502, a storage 503, an input / output interface (input / output I / F) 504, a communication interface (communication I / F) 505, and the like. The processor 501, the memory 502, the storage 503, the input / output interface 504, and the communication interface 505 are connected by a data transmission line for transmitting and receiving data to and from each other.
[0097]
The processor 501 is, for example, an arithmetic processing unit such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit). The memory 502 is, for example, a memory such as a RAM (Random Access Memory) or a ROM (Read Only Memory). The storage 503 is, for example, a storage device such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), or a memory card. Further, the storage 503 may be a memory such as RAM or ROM.
[0098]
The storage 503 stores a program that realizes the functions of the components (reception unit 21, determination unit 22, and notification unit 23) included in the optical fiber sensing device 20. By executing each of these programs, the processor 501 realizes the functions of the components included in the optical fiber sensing device 20. Here, when executing each of the above programs, the processor 501 may read these programs on the memory 502 and then execute the programs, or may execute the programs without reading them onto the memory 502. Further, the memory 502 and the storage 503 also play a role of storing information and data held by the components included in the optical fiber sensing device 20.
[0099]
Further, the above-mentioned program can be stored by using various types of non-transitory computer readable medium and supplied to a computer (including a computer 50). Non-temporary computer-readable media include various types of tangible storage media. Examples of non-temporary computer-readable media include magnetic recording media (eg, flexible disks, magnetic tapes, hard disk drives), optomagnetic recording media (eg, optomagnetic disks), CD-ROMs (Compact Disc-ROMs), CDs. -R (CD-Recordable), CD-R / W (CD-ReWritable), semiconductor memory (for example, mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM. , May be supplied to the computer by various types of transient computer readable media. Examples of transient computer readable media include electrical signals, optical signals, and electromagnetic waves. The computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.
[0100]
The input / output interface 504 is connected to a display device 5041, an input device 5042, a sound output device 5043, and the like. The display device 5041 is a device that displays a screen corresponding to drawing data processed by the processor 501, such as an LCD (Liquid Crystal Display), a CRT (Cathode Ray Tube) display, and a monitor. The input device 5042 is a device that receives an operator's operation input, and is, for example, a keyboard, a mouse, a touch sensor, and the like. The display device 5041 and the input device 5042 may be integrated and realized as a touch panel. The sound output device 5043 is a device such as a speaker that acoustically outputs sound corresponding to acoustic data processed by the processor 501.
[0101]
The communication interface 505 sends and receives data to and from an external device. For example, the communication interface 505 communicates with an external device via a wired communication path or a wireless communication path.
[0102]
Although the present disclosure has been described above with reference to the embodiments, the present disclosure is not limited to the above-described embodiments. Various changes that can be understood by those skilled in the art can be made to the structure and details of the present disclosure within the scope of the present disclosure.
For example, the above-described embodiment may be used in combination in part or in whole.
[0103]
Further, a part or all of the above embodiments may be described as in the following appendix, but the present invention is not limited to the following.
(Appendix 1)
The optical fiber laid in the piping and
A receiving unit that receives an optical signal on which the vibration detected by the optical fiber is superimposed from the optical fiber.
A determination unit that extracts the vibration pattern of the vibration detected by the optical fiber from the optical signal and determines the deterioration state of the pipe based on the extracted vibration pattern.
An optical fiber sensing system equipped with.
(Appendix 2)
The determination unit detects a sign of damage to the pipe based on the deterioration state.
The optical fiber sensing system described in Appendix 1.
(Appendix 3)
The determination unit identifies a position where a sign of damage to the pipe is detected based on the optical signal.
The optical fiber sensing system described in Appendix 2.
(Appendix 4)
The determination unit extracts vibration patterns at a plurality of points of the pipe from the optical signal, and obtains vibration patterns.
Based on the vibration patterns at the plurality of points of the pipe, the deterioration state of at least one of the plurality of points is determined.
The optical fiber sensing system according to any one of Supplementary note 1 to 3.
(Appendix 5)
The determination unit compares the vibration pattern of the vibration detected by the optical fiber with the matching pattern, and determines the deterioration state of the pipe based on the comparison result.
The optical fiber sensing system according to any one of Supplementary note 1 to 4.
(Appendix 6)
The determination unit changes the matching pattern according to the substance flowing through the pipe.
The optical fiber sensing system described in Appendix 5.
(Appendix 7)
Further provided with a notification unit for notifying an alert when the determination unit detects a sign of damage to the piping.
The optical fiber sensing system described in Appendix 3.
(Appendix 8)
Further equipped with a display unit
When the determination unit detects a sign of damage to the pipe, the notification unit maps the position where the sign of damage to the pipe is detected and displays it on the display unit.
The optical fiber sensing system described in Appendix 7.
(Appendix 9)
A receiving unit that receives an optical signal on which vibration detected by the optical fiber is superimposed from an optical fiber laid in a pipe.
A determination unit that extracts the vibration pattern of the vibration detected by the optical fiber from the optical signal and determines the deterioration state of the pipe based on the extracted vibration pattern.
An optical fiber sensing device equipped with.
(Appendix 10)
The determination unit detects a sign of damage to the pipe based on the deterioration state.
The optical fiber sensing device described in Appendix 9.
(Appendix 11)
The determination unit identifies a position where a sign of damage to the pipe is detected based on the optical signal.
The optical fiber sensing device according to Appendix 10.
(Appendix 12)
The determination unit extracts vibration patterns at a plurality of points of the pipe from the optical signal, and obtains vibration patterns.
Based on the vibration patterns at the plurality of points of the pipe, the deterioration state of at least one of the plurality of points is determined.
The optical fiber sensing device according to any one of Supplementary note 9 to 11.
(Appendix 13)
The determination unit compares the vibration pattern of the vibration detected by the optical fiber with the matching pattern, and determines the deterioration state of the pipe based on the comparison result.
The optical fiber sensing device according to any one of Supplementary note 9 to 12.
(Appendix 14)
The determination unit changes the matching pattern according to the substance flowing through the pipe.
The optical fiber sensing device described in Appendix 13.
(Appendix 15)
Further provided with a notification unit for notifying an alert when the determination unit detects a sign of damage to the piping.
The optical fiber sensing device according to Appendix 11.
(Appendix 16)
When the determination unit detects a sign of damage to the pipe, the notification unit maps the position where the sign of damage to the pipe is detected and displays it on the display unit.
The optical fiber sensing device according to Appendix 15.
(Appendix 17)
It is a piping deterioration detection method using an optical fiber sensing system.
The step that the optical fiber laid in the piping detects vibration,
A reception step of receiving an optical signal on which the vibration detected by the optical fiber is superimposed from the optical fiber,
A determination step of extracting a vibration pattern of vibration detected by the optical fiber from the optical signal and determining a deterioration state of the pipe based on the extracted vibration pattern.
Piping deterioration detection method including.
(Appendix 18)
In the determination step, a sign of damage to the pipe is detected based on the deterioration state.
The piping deterioration detection method described in Appendix 17.
(Appendix 19)
In the judgment step, Based on the optical signal, the position where the sign of the breakage of the pipe is detected is specified.
The piping deterioration detection method described in Appendix 18.
(Appendix 20)
In the judgment step,
The vibration patterns at multiple points of the piping were extracted from the optical signal,
Based on the vibration patterns at the plurality of points of the pipe, the deterioration state of at least one of the plurality of points is determined.
The piping deterioration detection method according to any one of Supplementary note 17 to 19.
(Appendix 21)
In the determination step, the vibration pattern of the vibration detected by the optical fiber is compared with the matching pattern, and the deterioration state of the pipe is determined based on the comparison result.
The piping deterioration detection method according to any one of Appendix 17 to 20.
(Appendix 22)
In the determination step, the matching pattern is changed according to the substance flowing through the pipe.
The piping deterioration detection method described in Appendix 21.
(Appendix 23)
If a sign of damage to the pipe is detected in the determination step, a notification step for notifying an alert is further included.
The piping deterioration detection method described in Appendix 19.
(Appendix 24)
In the notification step, when a sign of damage to the pipe is detected in the determination step, the position where the sign of damage to the pipe is detected is mapped and displayed on the display unit.
The piping deterioration detection method described in Appendix 23.
[0104]
This application claims priority based on Japanese application Japanese Patent Application No. 2019-131495 filed on July 16, 2019, and incorporates all of its disclosures herein.
Code description
[0105]
10 Optical fiber
20 Optical fiber sensing equipment
21 Receiver
22 Judgment unit
23 Notification unit
30 piping
31A-31C pillars
40 display unit
50 computers
501 processor
502 memory
503 storage
504 I / O interface
5041 Display device
5042 input device
5043 sound output device
505 communication interface
The scope of the claims
[Claim 1]
The optical fiber laid in the piping and
A receiving unit that receives an optical signal on which the vibration detected by the optical fiber is superimposed from the optical fiber.
A determination unit that extracts the vibration pattern of the vibration detected by the optical fiber from the optical signal and determines the deterioration state of the pipe based on the extracted vibration pattern.
An optical fiber sensing system equipped with.
[Claim 2]
The determination unit detects a sign of damage to the pipe based on the deterioration state.
The optical fiber sensing system according to claim 1.
[Claim 3]
The determination unit identifies a position where a sign of damage to the pipe is detected based on the optical signal.
The optical fiber sensing system according to claim 2.
[Claim 4]
The determination unit extracts vibration patterns at a plurality of points of the pipe from the optical signal, and obtains vibration patterns.
Based on the vibration patterns at the plurality of points of the pipe, the deterioration state of at least one of the plurality of points is determined.
The optical fiber sensing system according to any one of claims 1 to 3.
[Claim 5]
The determination unit compares the vibration pattern of the vibration detected by the optical fiber with the matching pattern, and determines the deterioration state of the pipe based on the comparison result.
The optical fiber sensing system according to any one of claims 1 to 4.
[Claim 6]
The determination unit changes the matching pattern according to the substance flowing through the pipe.
The optical fiber sensing system according to claim 5.
[Claim 7]
Further provided with a notification unit for notifying an alert when the determination unit detects a sign of damage to the piping.
The optical fiber sensing system according to claim 3.
[Claim 8]
Further equipped with a display unit
When the determination unit detects a sign of damage to the pipe, the notification unit maps the position where the sign of damage to the pipe is detected and displays it on the display unit.
The optical fiber sensing system according to claim 7.
[Claim 9]
A receiving unit that receives an optical signal on which vibration detected by the optical fiber is superimposed from an optical fiber laid in a pipe.
A determination unit that extracts the vibration pattern of the vibration detected by the optical fiber from the optical signal and determines the deterioration state of the pipe based on the extracted vibration pattern.
An optical fiber sensing device equipped with.
[Claim 10]
The determination unit detects a sign of damage to the pipe based on the deterioration state.
The optical fiber sensing device according to claim 9.
[Claim 11]
The determination unit identifies a position where a sign of damage to the pipe is detected based on the optical signal.
The optical fiber sensing device according to claim 10.
[Claim 12]
The determination unit extracts vibration patterns at a plurality of points of the pipe from the optical signal, and obtains vibration patterns.
Based on the vibration patterns at the plurality of points of the pipe, the deterioration state of at least one of the plurality of points is determined.
The optical fiber sensing device according to any one of claims 9 to 11.
[Claim 13]
The determination unit compares the vibration pattern of the vibration detected by the optical fiber with the matching pattern, and determines the deterioration state of the pipe based on the comparison result.
The optical fiber sensing device according to any one of claims 9 to 12.
[Claim 14]
The determination unit changes the matching pattern according to the substance flowing through the pipe.
The optical fiber sensing device according to claim 13.
[Claim 15]
Further provided with a notification unit for notifying an alert when the determination unit detects a sign of damage to the piping.
The optical fiber sensing device according to claim 11.
[Claim 16]
When the determination unit detects a sign of damage to the pipe, the notification unit maps the position where the sign of damage to the pipe is detected and displays it on the display unit.
The optical fiber sensing device according to claim 15.
[Claim 17]
It is a piping deterioration detection method using an optical fiber sensing system.
The step that the optical fiber laid in the piping detects vibration,
A reception step of receiving an optical signal on which the vibration detected by the optical fiber is superimposed from the optical fiber,
A determination step of extracting a vibration pattern of vibration detected by the optical fiber from the optical signal and determining a deterioration state of the pipe based on the extracted vibration pattern.
Piping deterioration detection method including.
[Claim 18]
In the determination step, a sign of damage to the pipe is detected based on the deterioration state.
The piping deterioration detection method according to claim 17.
[Claim 19]
In the determination step, the position where the sign of damage to the pipe is detected is specified based on the optical signal.
The piping deterioration detection method according to claim 18.
[Claim 20]
In the judgment step,
The vibration patterns at multiple points of the piping were extracted from the optical signal,
Based on the vibration patterns at the plurality of points of the pipe, the deterioration state of at least one of the plurality of points is determined.
The piping deterioration detection method according to any one of claims 17 to 19.
[Claim 21]
In the determination step, the vibration pattern of the vibration detected by the optical fiber is compared with the matching pattern, and the deterioration state of the pipe is determined based on the comparison result.
The piping deterioration detection method according to any one of claims 17 to 20.
[Claim 22]
In the determination step, the matching pattern is changed according to the substance flowing through the pipe.
The piping deterioration detection method according to claim 21.
[Claim 23]
If a sign of damage to the pipe is detected in the determination step, a notification step for notifying an alert is further included.
The piping deterioration detection method according to claim 19.
[Claim 24]
In the notification step, when a sign of damage to the pipe is detected in the determination step, the position where the sign of damage to the pipe is detected is mapped and displayed on the display unit.
The piping deterioration detection method according to claim 23.