Vehicle vibration extraction system, vehicle vibration extraction device, and method for extracting vehicle vibration

Abstract

To precisely extract a vehicle vibration component from measurement data of vibrations measured by optical fiber sensing.SOLUTION: The vehicle vibration extraction system according to the present disclosure includes: an acquisition unit for acquiring measurement data of vibrations that happened on a road from a sensing device for measuring vibrations that happened on a road by using an optical fiber buried in the road; and an extraction unit for performing a frequency filtering on measurement data by using a band limit filter with a passage band which corresponds to the road and the road surface state of the road, thereby extracting a vehicle vibration component from the measurement data.SELECTED DRAWING: Figure 16

Description

[Technical field]

[0001] The present disclosure relates to a vehicle vibration extraction system, a vehicle vibration extraction device, and a vehicle vibration extraction method. [Background technology]

[0002] Optical fiber sensing uses optical fiber buried in the road as a line sensor, and a sensing device connected to the optical fiber can measure the vehicle vibration of a vehicle traveling on the road throughout the entire section where the optical fiber is buried. The sensing device can also visualize the vehicle's trajectory by generating measurement data that shows the intensity of the measured vehicle vibration as a graph of the distance of the optical fiber from the sensing device versus time. In addition, by using existing optical fiber for communication as the optical fiber, it is possible to introduce a vehicle monitoring system at low cost.

[0003] However, the vibrations measured by optical fiber sensing contain noise components in addition to the vehicle vibration components. Therefore, in order to monitor a vehicle, it is necessary to perform a process to extract the vehicle vibration components from the vibration measurement data measured by optical fiber sensing.

[0004] As a related technique, for example, Patent Document 1 discloses a technique for detecting the amplitude and frequency of a vibration source such as a vehicle by frequency filtering the return light from an optical fiber using a low-pass filter or the like. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 07-198471 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the noise components contained in the vibrations measured by optical fiber sensing have different characteristics for each road, and even for the same road, the characteristics differ depending on the road surface condition. Therefore, even if the measurement data is frequency-filtered using the same filter, it is not possible to extract vehicle vibration components with high accuracy, regardless of the road or road surface conditions.

[0007] In view of the above-mentioned problems, an object of the present disclosure is to provide a vehicle vibration extraction system, a vehicle vibration extraction device, and a vehicle vibration extraction method capable of extracting vehicle vibration components with high accuracy from vibration measurement data measured by optical fiber sensing. [Means for solving the problem]

[0008] According to one aspect, a vehicle vibration extraction system includes: an acquisition unit that acquires measurement data of vibrations occurring on a road from a sensing device that measures vibrations occurring on the road using optical fibers buried in the road; and an extraction unit that extracts vehicle vibration components from the measurement data by frequency filtering the measurement data using a band-limiting filter having a passband corresponding to the road and the road surface condition of the road.

[0009] According to one aspect, a vehicle vibration extraction device includes: an acquisition unit that acquires measurement data of vibrations occurring on a road from a sensing device that measures vibrations occurring on the road using optical fibers buried in the road; and an extraction unit that extracts vehicle vibration components from the measurement data by frequency filtering the measurement data using a band-limiting filter having a passband corresponding to the road and the road surface condition of the road.

[0010] A vehicle vibration extraction method according to one aspect includes the steps of: A vehicle vibration extraction method executed by a vehicle vibration extraction device, comprising: acquiring measurement data of vibrations occurring on the road from a sensing device that measures vibrations occurring on the road using optical fibers buried in the road; The measurement data is frequency-filtered using a band-limiting filter having a passband corresponding to the road and the surface condition of the road, thereby extracting vehicle vibration components from the measurement data. Effect of the Invention

[0011] According to the above-mentioned aspects, it is possible to provide a vehicle vibration extraction system, a vehicle vibration extraction device, and a vehicle vibration extraction method that are capable of extracting vehicle vibration components with high accuracy from vibration measurement data measured by optical fiber sensing. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram illustrating the basic principle of the present disclosure. [Diagram 2] 1 is a diagram illustrating a schematic configuration example of a vehicle vibration extraction system according to the present disclosure. [Diagram 3] 1 is a diagram illustrating a schematic operation example of a vehicle vibration extraction system according to the present disclosure. [Figure 4] 1 is a flowchart illustrating an example of a schematic operation flow of a vehicle vibration extraction system according to the present disclosure. [Diagram 5] 1 is a diagram illustrating a schematic configuration example of a vehicle vibration extraction system according to the present disclosure. [Figure 6] 1 is a diagram illustrating a schematic operation example of a vehicle vibration extraction system according to the present disclosure. [Figure 7] 1 is a flowchart illustrating an example of a schematic operation flow of a vehicle vibration extraction system according to the present disclosure. [Figure 8] 1 is a diagram illustrating a schematic configuration example of a vehicle vibration extraction system according to the present disclosure. [Figure 9] 1 is a diagram illustrating a schematic operation example of a vehicle vibration extraction system according to the present disclosure. [Figure 10] 1 is a diagram illustrating a schematic operation example of a vehicle vibration extraction system according to the present disclosure. [Figure 11] 1 is a diagram illustrating a schematic operation example of a vehicle vibration extraction system according to the present disclosure. [Figure 12] FIG. 2 is a diagram showing an example of an image obtained from measurement data in the vehicle vibration extraction system according to the present disclosure when the road is Expressway X. [Figure 13] 1 is a diagram illustrating a schematic configuration example of a vehicle vibration extraction system according to the present disclosure. [Figure 14] 1 is a diagram illustrating a schematic operation example of a vehicle vibration extraction system according to the present disclosure. [Figure 15] 1 is a diagram showing an example of a power difference in measurement data in the frequency domain when the vehicle is moving and when the vehicle is not moving in a vehicle vibration extraction system according to the present disclosure; FIG. [Figure 16] 1 is a diagram illustrating a schematic configuration example of a vehicle vibration extraction system according to the present disclosure. [Figure 17] FIG. 2 is a block diagram showing an example of a hardware configuration of a computer that realizes the vehicle vibration extraction device according to the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. Note that the following description and drawings are omitted and simplified as appropriate for clarity of explanation. In addition, in each of the following drawings, the same elements are given the same reference numerals, and duplicated explanations are omitted as necessary. In addition, the specific numerical values ​​shown below are merely examples for facilitating understanding of the present disclosure, and are not limited thereto.

[0014] <Basic principles of this disclosure> Before describing each embodiment of the present disclosure, the basic principle of the present disclosure will be described with reference to FIG.

[0015] As described above, the sensing device can visualize the trajectory of the vehicle by generating measurement data that represents the intensity of the vehicle vibration measured by optical fiber sensing as a graph of the distance of the optical fiber from the sensing device and time. However, the vibration measured by optical fiber sensing includes not only the vehicle vibration component but also a noise component.

[0016] The left diagram in Fig. 1 shows three sets of measurement data, each divided into a low-frequency band, a mid-frequency band, and a high-frequency band, of vibration measurement data measured by optical fiber sensing using optical fiber buried in Expressway X, including a tunnel section. In addition, for each of these three sets of measurement data, the horizontal axis indicates the distance of the optical fiber from the sensing device, and the vertical axis indicates time (same for the center and right diagrams in Fig. 1).

[0017] The center diagram in Figure 1 shows three pieces of vibration measurement data, divided into bands similar to those shown in the left diagram, taken when the weather was fine (i.e., when the road surface of Expressway Y was dry) using optical fiber sensing with optical fiber buried under Expressway Y, which does not include the tunnel section.

[0018] The right side of Figure 1 shows three pieces of vibration measurement data measured by optical fiber sensing using optical fiber buried under highway Y, not including the tunnel section, when it was raining (i.e., when the road surface of highway Y was wet), divided into the same bands as in the left side.

[0019] Here, in each measurement data shown in Fig. 1, when a vehicle is traveling on a road, the vehicle is represented by a line. For example, one vehicle traveling on a road is represented by one diagonal line. The inclination of the diagonal line represents the traveling speed of the vehicle, and the smaller the inclination of the diagonal line, the faster the traveling speed of the vehicle.

[0020] For example, in the case of Expressway X, many diagonal lines are obtained in the low frequency band. In contrast, in the case of Expressway Y, when the weather is fine, many diagonal lines are obtained not only in the low frequency band but also in the mid and high frequency bands. However, when the weather is rainy, not many diagonal lines are obtained in the low frequency band, but many diagonal lines are obtained in the mid and high frequency bands.

[0021] In this way, it can be seen that the frequency at which the vehicle vibration component is dominant (in other words, the frequency at which the noise component is dominant) depends greatly on the road, and also depends greatly on the road surface conditions even for the same road.

[0022] Therefore, the present disclosure frequency-filters the measurement data using an optimal band-limiting filter according to the road and the surface conditions of that road, thereby separating the vehicle vibration components and noise components contained in the measurement data with high accuracy and extracting the vehicle vibration components from the measurement data with high accuracy. Each embodiment of the present disclosure will be described below.

[0023] <Embodiment 1> First, a schematic configuration example of the vehicle vibration extraction system 1 will be described with reference to FIG. The vehicle vibration extraction system 1 includes a vehicle vibration extraction device 10. The vehicle vibration extraction device 10 includes an acquisition unit 11 and an extraction unit 12.

[0024] The acquisition unit 11 acquires measurement data of vibrations occurring on a road from a sensing device (not shown). The sensing device is a device that performs optical fiber sensing to measure vibrations occurring on the road using optical fibers buried in the road, and is realized by, for example, a Distributed Fiber Optic Sensing (DFOS) device.

[0025] At this time, the acquisition unit 11 may input road information indicating a road and determine the road based on the input road information. Then, the acquisition unit 11 may acquire measurement data of vibrations occurring on the road determined above from a sensing device. Note that the road information may be input from an external device or may be input manually.

[0026] For example, the acquisition unit 11 acquires measurement data (time-series data) from the sensing device, which represents the intensity of vibrations occurring on the road as a graph of the distance of the optical fiber from the sensing device versus time. An example of this measurement data is the same as that shown in FIG.

[0027] In the following description, it is assumed that the acquiring unit 11 acquires, as measurement data, measurement data that represents the intensity of vibrations occurring on the road as a graph of the distance of the optical fiber from the sensing device versus time.

[0028] The extraction unit 12 performs frequency filtering on the measurement data acquired by the acquisition unit 11 using a band-limiting filter having a passband corresponding to the road and the road surface condition of the road, thereby extracting vehicle vibration components from the measurement data.

[0029] At this time, the extraction unit 12 may input road information indicating a road and road surface condition information indicating the road surface condition of the road, and may determine the road and the road surface condition of the road based on the input road information and road surface condition information. The extraction unit 12 may then perform frequency filtering using a band-limiting filter having a passband corresponding to the road and the road surface condition determined above. The road information and road surface condition information may be input from an external device or may be input manually. Alternatively, the extraction unit 12 may input weather information indicating the weather in the area including the road, instead of the road surface condition information, and determine the road surface condition of the road based on the input weather information.

[0030] The extraction unit 12 may also include a plurality of band-limiting filters having different pass bands. The extraction unit 12 may select and use a band-limiting filter having a pass band corresponding to the road and the road surface condition from the plurality of band-limiting filters. The band-limiting filter may be a band-pass filter or a low-pass filter, or may be any other filter capable of limiting the band of the measurement data to the pass band.

[0031] Next, a schematic operation example of the vehicle vibration extraction system 1 will be described with reference to Fig. 3. Here, it is assumed that the road indicated by the road information is road R1, and the road surface condition indicated by the road surface condition information or the weather information is road surface condition r1 (the same applies to Fig. 4 below).

[0032] First, the acquisition unit 11 acquires measurement data from the sensing device as measurement data of vibrations occurring on the road R1, the measurement data being a graph of the intensity of the vibrations occurring on the road R1 versus the distance of the optical fiber from the sensing device versus time (step X11).

[0033] Next, the extraction unit 12 performs frequency filtering on the measurement data using a band-limiting filter having a passband corresponding to the road R1 and the road surface condition r1 of the road R1, thereby extracting vehicle vibration components from the measurement data (step X12).

[0034] Thereafter, the extraction unit 12 outputs the data of the vehicle vibration components extracted from the measurement data as vehicle vibration extraction data (time-series data) (step X13).

[0035] For example, when the road R1 is the expressway X in Fig. 1, many diagonal lines are obtained in the low frequency band. Therefore, the extraction unit 12 extracts the vehicle vibration component by frequency filtering the measurement data using a band-limiting filter having a pass band for the low frequency band.

[0036] 1 and the road surface condition r1 is a road surface condition in fine weather (i.e., a dry state), many diagonal lines are obtained in the low frequency band, the medium frequency band, and the high frequency band. Therefore, the extraction unit 12 extracts the vehicle vibration component by frequency filtering the measurement data using a band limiting filter having a pass band that is a combination of the low frequency band, the medium frequency band, and the high frequency band.

[0037] 1 and the road surface condition r1 is a road surface condition in rainy weather (i.e., a wet state), many diagonal lines are obtained in the mid-frequency band and the high-frequency band. Therefore, the extraction unit 12 extracts the vehicle vibration component by frequency filtering the measurement data using a band-limiting filter having a pass band that is a combination of the mid-frequency band and the high-frequency band.

[0038] Next, an example of a schematic operation flow of the vehicle vibration extraction system 1 will be described with reference to FIG. First, the acquisition unit 11 acquires measurement data from the sensing device as measurement data of vibrations occurring on road R1, the measurement data being a graph of the intensity of vibrations occurring on road R1 versus time and the distance of the optical fiber from the sensing device (step S11).

[0039] Thereafter, the extraction unit 12 performs frequency filtering on the measurement data using a band-limiting filter having a passband corresponding to the road R1 and the road surface condition r1 of the road R1, thereby extracting vehicle vibration components from the measurement data (step S12).

[0040] As described above, according to the first embodiment, the acquisition unit 11 acquires measurement data of vibrations occurring on a road from a sensing device. The extraction unit 12 extracts vehicle vibration components from the measurement data by frequency filtering the measurement data using a band-limiting filter having a passband according to the road and the road surface condition of the road. This allows the measurement data to be frequency filtered using an optimal band-limiting filter according to the road and the road surface condition of the road, so that the vehicle vibration components can be extracted with high accuracy from the measurement data. As a result, vehicles traveling on the road can be detected with high accuracy.

[0041] For example, there are roads such as Expressway X in Fig. 1 that include many tunnels and the frequency at which the vehicle vibration components are dominant does not depend on the road surface condition. For such roads, the extraction unit 12 can frequency-filter the measurement data using a band-limiting filter having a passband corresponding to the road, regardless of the road surface condition of the road.

[0042] <Embodiment 2> First, with reference to FIG. 5, a schematic configuration example of a vehicle vibration extraction system 1A will be described. The vehicle vibration extraction system 1A includes a vehicle vibration extraction device 10A.

[0043] Compared with the vehicle vibration extraction device 10, the vehicle vibration extraction device 10A has a configuration in which a selection unit 13A is added. The selection unit 13A selects in advance, for each road and for each road surface condition of the road, a passband for when the road is in that road surface condition.

[0044] The extraction unit 12 performs frequency filtering on the measurement data using a band-limiting filter having a passband selected in advance by a selection unit 13A according to the road and the road surface condition.

[0045] Here, the selection unit 13A will be specifically described. For example, the selection unit 13A selects a passband for each road and for each road surface condition of the road, based on the vibration propagation characteristics of the road when the road is in that road surface condition. For example, when the road is road R1 and the road surface condition is road surface condition r1, the selection unit 13A may identify a band that is likely to propagate vehicle vibration on the road R1 when the road surface condition is r1. Then, the selection unit 13A may select the identified band as the passband when the road R1 is in the road surface condition r1.

[0046] Alternatively, the selection unit 13A selects a passband for each road and for each road surface condition of the road, based on the vibration propagation characteristics of the road and the vibration characteristics of the vehicle when the road is in that road surface condition. For example, when the road is road R1 and the road surface condition is road surface condition r1, the selection unit 13A may identify a band that easily propagates vehicle vibration on road R1 when the road surface condition is r1, and may also identify a band according to the vibration characteristics of the vehicle (e.g., suspension vibration, etc.). Then, the selection unit 13A may select the band identified by both as the passband when road R1 is in road surface condition r1.

[0047] Next, a schematic operation example of the vehicle vibration extraction system 1A will be described with reference to FIG. First, the operation of the pre-selection phase will be described. The selection unit 13A selects, for each road and for each road surface condition of the road, a passband when the road is in that road surface condition (step Y21).

[0048] For example, the selection unit 13A selects the passband when the road R1 is in the road surface condition r1 as follows. The selection unit 13A selects the passband based on the vibration propagation characteristics of the road R1 when the road R1 is in the road surface state r1. Alternatively, the selection unit 13A selects the passband based on the vibration propagation characteristics of the road R1 and the vibration characteristics of the vehicle when the road R1 is in the road surface state r1. The selection unit 13A performs the above-mentioned passband selection operation for each road and for each road surface condition of the road.

[0049] Next, the operation of the operation phase will be described. Here, it is assumed that the road indicated by the road information is road R1, and the road surface condition indicated by the road surface condition information or the weather information is road surface condition r1 (the same applies to the operation phase in FIG. 7 below).

[0050] First, the acquisition unit 11 acquires measurement data from the sensing device as measurement data of vibrations occurring on road R1, the measurement data being a graph of the intensity of vibrations occurring on road R1 versus time and the distance of the optical fiber from the sensing device (step X21).

[0051] Next, the extraction unit 12 performs frequency filtering on the measurement data using a band-limiting filter having a passband previously selected by the selection unit 13A according to the road R1 and the road surface condition r1 of the road R1, thereby extracting vehicle vibration components from the measurement data (step X22).

[0052] Thereafter, the extraction unit 12 outputs the data of the vehicle vibration component extracted from the measurement data as vehicle vibration extraction data (step X23).

[0053] Next, an example of a schematic operation flow of the vehicle vibration extraction system 1A will be described with reference to FIG. In the pre-selection phase, the selection unit 13A pre-selects, for each road and for each road surface condition, a passband for when the road is in that road surface condition (step S21). Specifically, the selection unit 13A selects a passband for each road and for each road surface condition based on the vibration propagation characteristics of the road when the road is in that road surface condition. Alternatively, the selection unit 13A selects a passband for each road and for each road surface condition based on the vibration propagation characteristics of the road and the vibration characteristics of the vehicle when the road is in that road surface condition.

[0054] In the subsequent operational phase, first, the acquisition unit 11 acquires from the sensing device measurement data of vibrations occurring on road R1, the measurement data being a graph of the intensity of vibrations occurring on road R1 versus the distance of the optical fiber from the sensing device versus time (step S22).

[0055] Thereafter, the extraction unit 12 extracts vehicle vibration components from the measurement data by frequency filtering the measurement data using a band-limiting filter having a passband previously selected by the selection unit 13A in accordance with the road R1 and the road surface condition r1 of the road R1 (step S23).

[0056] As described above, according to the second embodiment, the selection unit 13A selects in advance, for each road and for each road surface condition, a passband for when the road is in that road surface condition. Specifically, the selection unit 13A selects a passband for each road and for each road surface condition, based on the vibration propagation characteristics of the road when the road is in that road surface condition. Alternatively, the selection unit 13A selects a passband for each road and for each road surface condition, based on the vibration propagation characteristics of the road and the vibration characteristics of the vehicle when the road is in that road surface condition. This makes it possible to select in advance an optimal band-limiting filter according to the road and the road surface condition of the road. The other effects are the same as those of the first embodiment described above.

[0057] For example, there are roads such as the expressway X in Fig. 1 that include many tunnels and where the frequency at which the vehicle vibration components are dominant does not depend on the road surface condition. For such roads, the selection unit 13A only needs to select one passband for the road, regardless of the road surface condition of the road, and does not need to select a passband for each road surface condition of the road (the same applies to the following embodiments 3 and 4).

[0058] <Embodiment 3> First, with reference to FIG. 8, a schematic configuration example of a vehicle vibration extraction system 1B will be described. The vehicle vibration extraction system 1B includes a vehicle vibration extraction device 10B.

[0059] Compared to the vehicle vibration extraction device 10A, the vehicle vibration extraction device 10B has a configuration in which the selection unit 13A is replaced with a selection unit 13B. The selection unit 13B selects in advance, for each road and for each road surface condition of the road, a passband for when the road is in that road surface condition.

[0060] Here, the selection unit 13B will be specifically described. First, the acquisition unit 11 acquires, for each road and for each road surface condition, measurement data from the sensing device when the road is in that road surface condition. This measurement data is measurement data that represents the intensity of vibration generated when the road is in that road surface condition as a graph of the distance of the optical fiber from the sensing device and time.

[0061] Next, for each road and each road surface condition, the selection unit 13B divides the measurement data when the road is in that road surface condition into bands.The selection unit 13B then counts the number of diagonal lines representing a vehicle traveling on the road for the measurement data of each divided band.The selection unit 13B then selects a pass band when the road is in that road surface condition based on the counted number of diagonal lines.

[0062] In this case, in the measurement data, the inclination of the diagonal line corresponds to the traveling speed of the vehicle as described above. Therefore, the selection unit 13B may count the number of diagonal lines having the same inclination (i.e., the same traveling speed).

[0063] In addition, the selection unit 13B may tally up the number of diagonal lines in the measurement data for each divided band for each road and for each road surface condition, and select the band with the maximum number of diagonal lines as the pass band when the road is in that road surface condition.

[0064] Alternatively, when there is one band in which the number of diagonal lines is equal to or greater than a threshold as a result of tallying the number of diagonal lines for each band divided for each road and for each road surface condition, the selection unit 13B may select the band in which the number of diagonal lines is equal to or greater than a threshold as a pass band when the road is in that road surface condition. Also, when there are multiple bands in which the number of diagonal lines is equal to or greater than a threshold, the selection unit 13B may select a band that combines multiple bands in which the number of diagonal lines is equal to or greater than a threshold as a pass band when the road is in that road surface condition.

[0065] Next, a schematic operation example of the vehicle vibration extraction system 1B will be described with reference to Fig. 9 to Fig. 11. Fig. 10 shows an example of image transition of measurement data at each step of the pre-selection phase in Fig. 9. Fig. 11 shows an example of an enlarged view of the trajectory visualization image, the binarized image, and the histogram images of θ and ρ after the Hough transform in Fig. 10.

[0066] First, the operation of the pre-selection phase will be described. First, the acquisition unit 11 acquires, for each road and for each road surface condition, measurement data from the sensing device when the road is in that road surface condition (step Y31). Thereafter, the selection unit 13B selects, for each road and for each road surface condition of the road, a passband for when the road is in that road surface condition.

[0067] For example, the selection unit 13B selects the passband when the road R1 is in the road surface condition r1 as follows. First, the selection unit 13B divides the measurement data when the road R1 is in the road surface condition r1 into bands (step Y32). Here, the measurement data is subjected to frequency filtering to divide the data into bands of 0-2 Hz, 2-4 Hz, 4-8 Hz, .... As a result, the image of the measurement data in each divided band is converted into a trajectory visualization image in which the trajectory of the vehicle is visualized (step Y33).

[0068] Next, the selection unit 13B binarizes the trajectory visualization image of the measurement data for each divided band, converts it into a binary image, performs a Hough transform on the converted binary image, and detects diagonal lines using a histogram image of θ and ρ after the Hough transform (step Y34).

[0069] Here, in the histogram image of θ and ρ after the Hough transform, θ corresponds to the inclination angle of the diagonal line. The vehicle trajectories are generally concentrated at the same θ (here, θ = around 2.7 to 2.9). On the other hand, the horizontal or vertical line components in the measurement data appear near θ = 0, π / 2 (≒ 1.57).

[0070] Therefore, the selection unit 13B counts up the number of diagonal lines in the vicinity of θ=2.7 to 2.9 (step Y35). Thereafter, the selection unit 13B selects a passband when the road R1 is in the road surface condition r1, based on the counted number of diagonal lines (step Y36).

[0071] Here, the upper diagram of Fig. 12 shows an example of a trajectory visualization image and a histogram image after Hough transform obtained without band division of the measurement data of the entire frequency band when road R1 is highway X. Also, the lower diagram of Fig. 12 shows an example of a trajectory visualization image and a histogram image after Hough transform obtained after dividing the measurement data into low frequency bands when road R1 is highway X. As such, it can be seen that many diagonal lines are obtained in the measurement data of the low frequency band. Therefore, in the example of FIG. 12, the selection unit 13B selects the low frequency band as the pass band when the road R1 is the expressway X, for example.

[0072] The selection unit 13B performs the above-mentioned passband selection operation for each road and for each road surface condition of the road.

[0073] Incidentally, the operation (steps X31 to X33) of the operation phase of FIG. 9 in the vehicle vibration extraction system 1B is similar to the operation (steps X21 to X23) of the operation phase of FIG. 6 in the above-described vehicle vibration extraction system 1A, and therefore the description thereof will be omitted.

[0074] Moreover, the flow of operations in the vehicle vibration extraction system 1B is similar to the flow of operations (steps S21 to S23) in the above-described vehicle vibration extraction system 1A shown in FIG. 7, and therefore a description thereof will be omitted.

[0075] As described above, according to the third embodiment, the selection unit 13B selects in advance a passband for each road and for each road surface condition of the road when the road is in that road surface condition. Specifically, the acquisition unit 11 acquires measurement data for each road and for each road surface condition of the road when the road is in that road surface condition. The selection unit 13B divides the measurement data for each road and for each road surface condition of the road into bands, counts the number of diagonal lines for the measurement data of each divided band, and selects a passband based on the counted number of diagonal lines. This makes it possible to select in advance an optimal band-limiting filter according to the road and the road surface condition of the road. The other effects are the same as those of the first embodiment described above.

[0076] <Fourth embodiment> First, with reference to FIG. 13, a schematic configuration example of a vehicle vibration extraction system 1C will be described. The vehicle vibration extraction system 1C includes a vehicle vibration extraction device 10C.

[0077] Compared to the vehicle vibration extraction device 10A, the vehicle vibration extraction device 10C has a configuration in which the selection unit 13A is replaced with a selection unit 13C. The selection unit 13C selects in advance, for each road and for each road surface condition of the road, a passband for when the road is in that road surface condition.

[0078] Here, the selection unit 13C will be specifically described. First, the acquisition unit 11 acquires, for each road and for each road surface condition, measurement data from the sensing device when the road is in that road surface condition. This measurement data is measurement data that represents the intensity of vibration generated when the road is in that road surface condition as a graph of the distance of the optical fiber from the sensing device and time.

[0079] Next, for each road and each road surface condition, the selection unit 13C extracts measurement data when a vehicle is traveling on the road and measurement data when a vehicle is not traveling on the road from the measurement data when the road is in that road surface condition.The selection unit 13C then calculates the power difference (i.e., the difference in vibration intensity) in the frequency domain between the two extracted measurement data, and selects a passband when the road is in that road surface condition based on the calculated power difference.

[0080] At this time, the selection unit 13C may use camera information from a camera that is installed on the road and synchronized with the vehicle vibration extraction system 1C to determine whether a vehicle is traveling on the road or not.

[0081] In addition, the selection unit 13C may calculate the power difference for each road and for each road surface condition of the road, and select the band in which the calculated power difference is maximum as the passband when the road is in that road surface condition.

[0082] Alternatively, when there is one band in which the power difference is equal to or greater than the threshold as a passband when the road is in that road surface condition as a result of calculating the power difference for each road and each road surface condition, the selection unit 13C may select the band in which the power difference is equal to or greater than the threshold as a passband when the road is in that road surface condition. Also, when there are multiple bands in which the power difference is equal to or greater than the threshold, the selection unit 13C may select a band that combines multiple bands in which the power difference is equal to or greater than the threshold as a passband when the road is in that road surface condition.

[0083] Next, a schematic operation example of the vehicle vibration extraction system 1C will be described with reference to FIG.

[0084] First, the operation of the pre-selection phase will be described. First, the acquisition unit 11 acquires, for each road and for each road surface condition, measurement data from the sensing device when the road is in that road surface condition (step Y41). Thereafter, the selection unit 13C selects, for each road and for each road surface condition of the road, a passband for when the road is in that road surface condition.

[0085] For example, the selection unit 13C selects the passband when the road R1 is in the road surface condition r1 as follows. First, the selection unit 13C extracts measurement data when a vehicle is traveling on road R1 from the measurement data when road R1 is in road surface condition r1 (step Y42), and also extracts measurement data when a vehicle is not traveling on road R1 (step Y44).

[0086] Next, the selection unit 13C performs FFT (Fast Fourier Transform) on the measurement data when the vehicle is traveling on the road R1 (step Y43), and also performs FFT on the measurement data when the vehicle is not traveling on the road R1 (step Y45).

[0087] Next, the selection unit 13C calculates the power difference in the frequency domain between the two pieces of measurement data subjected to FFT (that is, the difference in vibration intensity) (step Y46). Thereafter, the selection unit 13C selects a passband when the road R1 is in the road surface condition r1, based on the calculated power difference.

[0088] Here, Fig. 15 shows an example of the power difference (i.e., the difference in vibration intensity) of the measurement data in the frequency domain when the vehicle is moving and when the vehicle is not moving, when the road R1 is in road surface condition r1. In Fig. 15, the horizontal axis represents frequency, and the vertical axis represents power (vibration intensity). In the example of FIG. 15, it can be seen that the power difference is large in the band from f1 to f2. Therefore, in the example of FIG. 15, the selection unit 13C selects, for example, the band from f1 to f2 as the passband when the road R1 is in the road surface condition r1.

[0089] The selection unit 13C performs the above-mentioned passband selection operation for each road and for each road surface condition of the road.

[0090] Incidentally, the operation (steps X41 to X43) of the operation phase of FIG. 14 in the vehicle vibration extraction system 1C is similar to the operation (steps X21 to X23) of the operation phase of FIG. 6 in the above-described vehicle vibration extraction system 1A, and therefore the description thereof will be omitted.

[0091] Moreover, the flow of operations in the vehicle vibration extraction system 1C is similar to the flow of operations (steps S21 to S23) in the above-described vehicle vibration extraction system 1A shown in FIG. 7, and therefore a description thereof will be omitted.

[0092] As described above, according to the fourth embodiment, the selection unit 13C selects in advance, for each road and for each road surface condition, a passband when the road is in that road surface condition. Specifically, the acquisition unit 11 acquires, for each road and for each road surface condition, measurement data when the road is in that road surface condition. For each road and for each road surface condition, the selection unit 13C extracts measurement data when a vehicle is traveling on the road and measurement data when a vehicle is not traveling on the road from the measurement data when the road is in that road surface condition, calculates the power difference (difference in vibration intensity) between the two extracted measurement data in the frequency domain, and selects a passband based on the calculated power difference. This allows an optimal band-limiting filter to be selected in advance according to the road and the road surface condition of the road. The other effects are the same as those of the first embodiment described above.

[0093] <Other embodiments> In the above-mentioned first to fourth embodiments, the acquisition unit 11, the extraction unit 12, and the selection units 13A, 13B, and 13C are provided inside the vehicle vibration extraction devices 10, 10A, 10B, and 10C, but this is not limited thereto. The acquisition unit 11, the extraction unit 12, and the selection units 13A, 13B, and 13C may be provided in different devices or on the cloud. FIG. 16 shows a configuration example of a vehicle vibration extraction system 1D in which the acquisition unit 11 and the extraction unit 12 are provided in different devices or on the cloud. Note that the vehicle vibration extraction system 1D shown in FIG. 16 may additionally include the selection units 13A, 13B, and 13C in the above-mentioned vehicle vibration extraction devices 10A, 10B, and 10C.

[0094] <Hardware configuration of the vehicle vibration extraction device according to the embodiment> Next, with reference to FIG. 17, an example of the hardware configuration of a computer that realizes the above-described vehicle vibration extraction devices 10, 10A, 10B, and 10C will be described.

[0095] 17, a computer 90 includes a processor 91, a memory 92, a storage 93, an input / output interface (input / output I / F) 94, and a communication interface (communication I / F) 95. The processor 91, the memory 92, the storage 93, the input / output interface 94, and the communication interface 95 are connected by a data transmission path for transmitting and receiving data to and from each other.

[0096] The processor 91 is, for example, an arithmetic processing device such as a central processing unit (CPU) or a graphics processing unit (GPU). The memory 92 is, for example, a random access memory (RAM) or a read only memory (ROM). The storage 93 is, for example, a storage device such as a hard disk drive (HDD), a solid state drive (SSD), or a memory card. The storage 93 may also be a memory such as a RAM or a ROM.

[0097] A program is stored in the storage 93. When the program is loaded into the computer, it includes a set of instructions (or software code) for causing the computer 90 to perform one or more functions of the above-described vehicle vibration extraction devices 10, 10A, 10B, and 10C. The components of the above-described vehicle vibration extraction devices 10, 10A, 10B, and 10C may be realized by the processor 91 reading and executing the program stored in the storage 93. In addition, the storage function of the above-described vehicle vibration extraction devices 10, 10A, 10B, and 10C may be realized by the memory 92 or the storage 93.

[0098] The above-mentioned programs may also be stored on non-transitory computer-readable media or tangible storage media. By way of example and not limitation, computer-readable media or tangible storage media include RAM, ROM, flash memory, SSD or other memory technology, CD (Compact Disc)-ROM, DVD (Digital Versatile Disc), Blu-ray (registered trademark) disk or other optical disk storage, magnetic cassette, magnetic tape, magnetic disk storage or other magnetic storage device. The programs may also be transmitted on a transitory computer-readable medium or communication medium. By way of example and not limitation, transitory computer-readable media or communication media include electrical, optical, acoustic, or other forms of propagated signals.

[0099] The input / output interface 94 is connected to a display device 941, an input device 942, a sound output device 943, and the like. The display device 941 is a device that displays a screen corresponding to drawing data processed by the processor 91, such as an LCD (Liquid Crystal Display), a CRT (Cathode Ray Tube) display, or a monitor. The input device 942 is a device that accepts an operation input by an operator, and is, for example, a keyboard, a mouse, or a touch sensor. The display device 941 and the input device 942 may be integrated and realized as a touch panel. The sound output device 943 is a device that acoustically outputs a sound corresponding to the sound data processed by the processor 91, such as a speaker.

[0100] The communication interface 95 transmits and receives data to and from an external device. For example, the communication interface 95 communicates with the external device via a wired communication path or a wireless communication path.

[0101] Although the present disclosure has been described above with reference to the embodiments, the present disclosure is not limited to the above-mentioned embodiments. Various modifications that can be understood by a person skilled in the art can be made to the configuration and details of the present disclosure within the scope of the present disclosure. Furthermore, each embodiment can be appropriately combined with other embodiments.

[0102] Moreover, each drawing is merely an example for describing one or more embodiments. Each drawing may relate not only to one particular embodiment, but to one or more other embodiments. As can be understood by those skilled in the art, various features or steps described with reference to any one drawing may be combined with features or steps shown in one or more other drawings to create an embodiment not explicitly shown or described, for example. Not all features or steps shown in any one drawing are necessarily required to describe an exemplary embodiment, and some features or steps may be omitted. The order of steps described in any drawing may be changed as appropriate.

[0103] Furthermore, some or all of the above-described embodiments can be described as, but are not limited to, the following supplementary notes. (Appendix 1) an acquisition unit that acquires measurement data of vibrations occurring on a road from a sensing device that measures vibrations occurring on the road using optical fibers buried in the road; an extraction unit that extracts a vehicle vibration component from the measurement data by frequency filtering the measurement data using a band-limiting filter having a passband corresponding to the road and a surface condition of the road; Vehicle vibration extraction system. (Appendix 2) a selection unit that selects in advance a passband for each of the roads and for each road surface condition of the road when the road is in the road surface condition; the extraction unit performs frequency filtering on the measurement data using a band-limiting filter having a passband selected in advance by the selection unit in accordance with the road and a surface condition of the road; 2. The vehicle vibration extraction system of claim 1. (Appendix 3) the selection unit selects the passband for each of the roads and for each road surface state of the road, based on vibration propagation characteristics of the road when the road is in the road surface state. 3. The vehicle vibration extraction system of claim 2. (Appendix 4) the selection unit selects the passband for each of the roads and for each road surface condition of the road, based on vibration propagation characteristics of the road and vibration characteristics of the vehicle when the road is in the road surface condition. 3. The vehicle vibration extraction system of claim 2. (Appendix 5) the acquisition unit acquires, for each of the roads and for each road surface condition of the road, measurement data representing an intensity of vibration occurring on the road as a graph of a distance of the optical fiber from the sensing device versus time, as the measurement data when the road is in the road surface condition; the selection unit divides, for each road and for each road surface condition of the road, the measurement data when the road is in the road surface condition into bands, counts the number of diagonal lines in the measurement data of each divided band, and selects the pass band based on the counted number of diagonal lines. 3. The vehicle vibration extraction system of claim 2. (Appendix 6) the selection unit counts the number of the diagonal lines for each of the roads and for each road surface condition of the road, and selects, as the passband, a band in which the number of the diagonal lines is maximum. 6. The vehicle vibration extraction system of claim 5. (Appendix 7) the selection unit, when there is one band in which the number of diagonal lines is equal to or greater than a threshold as a result of tallying up the number of diagonal lines for each road and for each road surface condition of the road, selects the band in which the number of diagonal lines is equal to or greater than a threshold as the passband, and when there are multiple bands in which the number of diagonal lines is equal to or greater than a threshold, selects a band that combines the multiple bands in which the number of diagonal lines is equal to or greater than a threshold as the passband. 6. The vehicle vibration extraction system of claim 5. (Appendix 8) the selection unit performs a Hough transform on the measurement data of each divided band for each road and for each road surface condition of the road, and counts the number of the diagonal lines using the Hough transformed image. 6. The vehicle vibration extraction system of claim 5. (Appendix 9) the acquisition unit acquires, for each of the roads and for each road surface condition of the road, measurement data representing an intensity of vibration occurring on the road as a graph of a distance of the optical fiber from the sensing device versus time, as the measurement data when the road is in the road surface condition; the selection unit extracts, for each road and for each road surface condition of the road, measurement data when a vehicle is traveling on the road and measurement data when a vehicle is not traveling on the road from the measurement data when the road is in the road surface condition, calculates a difference in vibration intensity in a frequency domain between the two extracted measurement data, and selects the passband based on the calculated difference in vibration intensity. 3. The vehicle vibration extraction system of claim 2. (Appendix 10) the selection unit calculates the difference in vibration intensity for each of the roads and for each road surface condition of the road, and selects, as the pass band, a band in which the calculated difference in vibration intensity is a maximum value. 10. The vehicle vibration extraction system of claim 9. (Appendix 11) the selection unit, when there is one band in which the difference in vibration strength is equal to or greater than a threshold as a result of calculating the difference in vibration strength for each road and for each road surface condition of the road, selects the band in which the difference in vibration strength is equal to or greater than a threshold as the pass band, and when there are multiple bands in which the difference in vibration strength is equal to or greater than a threshold, selects a band that is a combination of multiple bands in which the difference in vibration strength is equal to or greater than a threshold as the pass band. 10. The vehicle vibration extraction system of claim 9. (Appendix 12) the extraction unit inputs weather information for an area including the road, and determines a road surface condition of the road based on the input weather information; 2. The vehicle vibration extraction system of claim 1. (Appendix 13) the extraction unit includes a plurality of band-limiting filters having different pass bands, and selects and uses a band-limiting filter having a pass band corresponding to the road and a road surface condition of the road from among the plurality of band-limiting filters. 2. The vehicle vibration extraction system of claim 1. (Appendix 14) an acquisition unit that acquires measurement data of vibrations occurring on a road from a sensing device that measures vibrations occurring on the road using optical fibers buried in the road; an extraction unit that extracts a vehicle vibration component from the measurement data by frequency filtering the measurement data using a band-limiting filter having a passband corresponding to the road and a surface condition of the road; Vehicle vibration extraction device. (Appendix 15) A vehicle vibration extraction method executed by a vehicle vibration extraction device, comprising: acquiring measurement data of vibrations occurring on the road from a sensing device that measures vibrations occurring on the road using optical fibers buried in the road; extracting a vehicle vibration component from the measurement data by frequency filtering the measurement data using a band-limiting filter having a passband corresponding to the road and a surface condition of the road; Vehicle vibration extraction method.

[0104] Some or all of the elements (e.g., configurations and functions) described in Supplementary Notes 2 to 13 that are dependent on Supplementary Note 1 may also be dependent on Supplementary Notes 14 and 15 in the same dependent relationship as Supplementary Notes 2 to 13. Some or all of the elements described in any Supplementary Note may be applied to various hardware, software, recording means for recording software, systems, and methods. [Explanation of symbols]

[0105] 1,1A,1B,1C,1D Vehicle vibration extraction system 10, 10A, 10B, 10C Vehicle vibration extraction device 11 Acquisition Department 12 Extraction part 13A, 13B, 13C selection section 90 Computer 91 Processor 92 Memory 93 Storage 94 Input / Output Interface 941 Display device 942 Input Device 943 Sound output device 95 Communication Interface

Claims

1. an acquisition unit that acquires measurement data of vibrations occurring on a road from a sensing device that measures vibrations occurring on the road using optical fibers buried in the road; an extraction unit that extracts a vehicle vibration component from the measurement data by frequency filtering the measurement data using a band-limiting filter having a passband corresponding to the road and a surface condition of the road; Vehicle vibration extraction system.

2. a selection unit that selects in advance a passband for each of the roads and for each road surface condition of the road when the road is in the road surface condition; the extraction unit performs frequency filtering on the measurement data using a band-limiting filter having a passband selected in advance by the selection unit in accordance with the road and a surface condition of the road; The vehicle vibration extraction system of claim 1 .

3. the selection unit selects the passband for each of the roads and for each road surface state of the road, based on vibration propagation characteristics of the road when the road is in the road surface state. The vehicle vibration extraction system of claim 2 .

4. the selection unit selects the passband for each of the roads and for each road surface condition of the road, based on vibration propagation characteristics of the road and vibration characteristics of the vehicle when the road is in the road surface condition. The vehicle vibration extraction system of claim 2 .

5. the acquisition unit acquires, for each of the roads and for each road surface condition of the road, measurement data representing an intensity of vibration occurring on the road as a graph of a distance of the optical fiber from the sensing device versus time, as the measurement data when the road is in the road surface condition; the selection unit divides, for each road and for each road surface condition of the road, the measurement data when the road is in the road surface condition into bands, counts the number of diagonal lines in the measurement data of each divided band, and selects the pass band based on the counted number of diagonal lines. The vehicle vibration extraction system of claim 2 .

6. the selection unit counts the number of the diagonal lines for each of the roads and for each road surface condition of the road, and selects, as the passband, a band in which the number of the diagonal lines is maximum. The vehicle vibration extraction system of claim 5 .

7. the selection unit, when there is one band in which the number of diagonal lines is equal to or greater than a threshold as a result of tallying up the numbers of the diagonal lines for each road and for each road surface condition of the road, selects the band in which the number of the diagonal lines is equal to or greater than a threshold as the passband, and when there are multiple bands in which the number of the diagonal lines is equal to or greater than a threshold, selects a band that combines the multiple bands in which the number of the diagonal lines is equal to or greater than a threshold as the passband. The vehicle vibration extraction system of claim 5 .

8. the selection unit performs a Hough transform on the measurement data of each divided band for each road and for each road surface condition of the road, and counts the number of the diagonal lines using the Hough transformed image. The vehicle vibration extraction system of claim 5 .

9. the acquisition unit acquires, for each of the roads and for each road surface condition of the road, measurement data representing an intensity of vibration occurring on the road as a graph of a distance of the optical fiber from the sensing device versus time, as the measurement data when the road is in the road surface condition; the selection unit extracts, for each road and for each road surface condition of the road, measurement data when a vehicle is traveling on the road and measurement data when a vehicle is not traveling on the road from the measurement data when the road is in the road surface condition, calculates a difference in vibration intensity in a frequency domain between the two extracted measurement data, and selects the passband based on the calculated difference in vibration intensity. The vehicle vibration extraction system of claim 2 .

10. the selection unit calculates the difference in vibration intensity for each of the roads and for each road surface condition of the road, and selects, as the pass band, a band in which the calculated difference in vibration intensity is a maximum value. The vehicle vibration extraction system of claim 9.

11. the selection unit, when there is one band in which the vibration strength difference is equal to or greater than a threshold value as a result of calculating the vibration strength difference for each road and each road surface condition of the road, selects the band in which the vibration strength difference is equal to or greater than a threshold value as the pass band, and when there are multiple bands in which the vibration strength difference is equal to or greater than a threshold value, selects a band that is a combination of multiple bands in which the vibration strength difference is equal to or greater than a threshold value as the pass band. The vehicle vibration extraction system of claim 9.

12. the extraction unit inputs weather information for an area including the road, and determines a road surface condition of the road based on the input weather information; The vehicle vibration extraction system of claim 1 .

13. the extraction unit includes a plurality of band-limiting filters having different pass bands, and selects and uses a band-limiting filter having a pass band corresponding to the road and a road surface condition of the road from among the plurality of band-limiting filters. The vehicle vibration extraction system of claim 1 .

14. an acquisition unit that acquires measurement data of vibrations occurring on a road from a sensing device that measures vibrations occurring on the road using optical fibers buried in the road; an extraction unit that extracts a vehicle vibration component from the measurement data by frequency filtering the measurement data using a band-limiting filter having a passband corresponding to the road and a surface condition of the road; Vehicle vibration extraction device.

15. A vehicle vibration extraction method executed by a vehicle vibration extraction device, comprising: acquiring measurement data of vibrations occurring on the road from a sensing device that measures vibrations occurring on the road using optical fibers buried in the road; extracting a vehicle vibration component from the measurement data by frequency filtering the measurement data using a band-limiting filter having a passband corresponding to the road and a surface condition of the road; Vehicle vibration extraction method.

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