Inspection device

Abstract

To provide an inspection device that can combine a plurality of coordinate information based on a feature point of the shape of an inspection object and continuously inspect wear of a rail.SOLUTION: An inspection device 10 comprises: a projection unit 11 that projects image light of a pattern image on a wear inspection object; an imaging unit 12 that picks up an image of the inspection object on which the image light is projected to create a first image, and picks up an image of an inspection object on which the image light of the pattern image is not projected to create a second image; a first noise removal unit 111 that removes noise from the first image; a phase conversion unit 112 that converts the first image into phase information; a second noise removal unit 113 that removes phase information other than phase information on the pattern image as noise; a change amount acquisition unit 114 that acquires the amount of change in phase based on the phase information; a coordinate conversion unit 115 that converts the change amount into coordinate information; a feature point specification unit 116 that specifies a feature point of the shape of the inspection object based on the coordinate information; and a combination unit 117 that combines the plurality of pieces of coordinate information based on the feature point.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an inspection apparatus.

Background Art

[0002] Conventionally, a technique for inspecting wear such as corrugation wear occurring on rails used for railway tracks has been known (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the corrugation wear inspection apparatus disclosed in Patent Document 1, although it is possible to inspect a part of the wear of the laid rails, it has been difficult to continuously inspect the wear of the rails.

Means for Solving the Problems

[0005] The inspection device for achieving the above object includes a projection unit that projects image light of a pattern image onto an inspection target of wear, an imaging unit that images the inspection target onto which the image light of the pattern image is projected to generate a first image, and images the inspection target onto which the image light of the pattern image is not projected to generate a second image, a first noise removal unit that removes noise from the first image based on the first image and the second image, a phase conversion unit that converts the first image from which noise has been removed by the first noise removal unit into phase information, a second noise removal unit that removes phase information other than the phase information of the pattern image as noise from the phase information, a change amount acquisition unit that acquires a change amount of the phase based on the phase information from which noise has been removed by the second noise removal unit, a coordinate conversion unit that converts the change amount into coordinate information with the imaging unit as the origin, a feature point identification unit that identifies feature points of the shape of the inspection target based on the coordinate information, and a synthesis unit that synthesizes a plurality of the coordinate information based on the feature points.

[0006] According to such a configuration, the inspection device can synthesize a plurality of pieces of coordinate information based on the feature points of the shape of the inspection target and continuously inspect the wear of the rail. In the above inspection device, it may further include a reception unit that receives a user's operation, and an output unit that outputs shape information indicating the shape of the wear existing in the range of the inspection target indicated by the user's operation.

[0007] According to such a configuration, the user can refer to the information of the designated inspection range among the information related to the wear of the continuously inspected rail. In the above inspection device, the shape information may be a statistical value indicating the shape of the wear.

[0008] According to such a configuration, the user can refer to the statistical value indicating the shape of the wear in the designated inspection range. In the above inspection device, the shape information may be three-dimensional data indicating the shape of the wear.

[0009] According to such a configuration, the user can refer to the three-dimensional data indicating the shape of wear in the specified inspection range. In the inspection apparatus, the pattern image may be a first pattern image showing a stripe pattern in a direction parallel to the stretching direction of the inspection target, or a second pattern image showing a stripe pattern in a direction orthogonal to the stretching direction.

[0010] According to such a configuration, the wear of the rail can be inspected more accurately. In the inspection apparatus, the imaging unit generates a plurality of the first images using a plurality of the first pattern images in which part or all of the widths of the stripe patterns are different from each other, or a plurality of the second pattern images in which the widths of the stripe patterns are different from each other. The first noise removal unit removes noise from the first image based on the second image having an angle of view that matches or substantially matches the angle of view shown in the first image. The coordinate conversion unit may convert the coordinate information for each of the plurality of phase information based on the plurality of the first images having matching or substantially matching angles of view.

[0011] According to such a configuration, the wear of the rail can be inspected efficiently.

Advantages of the Invention

[0012] According to the present invention, the inspection apparatus can synthesize a plurality of pieces of coordinate information based on the feature points of the shape of the inspection target and continuously inspect the wear of the rail.

Brief Description of the Drawings

[0013]

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Embodiments for Carrying Out the Invention

[0014] <Embodiment> [Overall Configuration] Hereinafter, with reference to the drawings, an embodiment in which the inspection device is embodied will be described. As shown in FIG. 1, the inspection system 1 includes an inspection device 10 for inspecting wear occurring on the rail L1, a driving bogie 20 for causing the inspection device 10 to travel on the rail L1, and a rail head trimming device (not shown). For example, an inspector U1 rides on the driving bogie 20. The inspector U1 operates the driving bogie 20 to cause the inspection system 1 to travel on the rail L1.

[0015] In the following description, one horizontal direction is referred to as X, the other direction as Y, and the vertical direction orthogonal to the X - Y horizontal direction as Z. The X - axis direction is, for example, the extending direction of the rail L1. The +X - axis direction is the forward direction of the inspection system 1, and the -X - axis direction is the backward direction of the inspection system 1. The Y - axis direction is, for example, the width direction of the rail L1. The +Y - axis direction is the right direction of the inspection system 1, and the -Y - axis direction is the left direction of the inspection system 1.

[0016] The rail head correction device has a grinding wheel that contacts the head of the rail L1. When the inspection system 1 travels on the rail L1, the grinding wheel corrects the wear generated on the head of the rail L1. Note that the rail head correction device may have a constant contact angle of the grinding wheel with respect to the head of the rail L1, or the contact angle of the grinding wheel with respect to the head of the rail L1 may be changeable and may have a structure (such as an adjustment bolt or a feed screw mechanism) for changing the contact angle. Further, the rail head correction device may be driven by an electric motor.

[0017] In the present embodiment, the inspection device 10 inspects the wear generated on the rail L1 before being corrected by the rail head correction device. That is, in the inspection system 1, the inspection device 10 is provided in front of the rail head correction device in the traveling direction. The inspection device 10 includes a projection unit 11 and an imaging unit 12. The inspection device 10 inspects the wear of the rail L1 based on the image generated when the imaging unit 12 images the rail L1 in a state where the projection unit 11 projects image light or in a state where the projection unit 11 does not project image light. The rail L1 is an example of an "inspection target". Hereinafter, the details of the inspection device 10 will be described.

[0018] [Configuration of Inspection Device 10] As shown in FIG. 2, the inspection device 10 includes a projection unit 11, an imaging unit 12, a reception unit 13, a display unit 14, a control unit 100, and a storage unit 200.

[0019] The projection unit 11 is realized by, for example, a projector that projects an image. The projection unit 11 projects the image light of the pattern image described later onto the rail L1. The imaging unit 12 is realized by, for example, a digital camera that uses a solid-state imaging device such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor).

[0020] The reception unit 13 receives the operations of the user of the inspection device 10. The reception unit 13 is realized by, for example, a touch panel, a keyboard, and a mouse. The display unit 14 is realized by, for example, a display or the like, and displays various images based on the control of the control unit 100. Note that the reception unit 13 and the display unit 14 may be integrally configured and realized by a display or the like having a touch panel function. The display unit 14 is an example of an "output unit".

[0021] The control unit 100 is realized, for example, when a hardware processor such as a CPU (Central Processing Unit) executes a program (software). Further, some or all of these components may be realized by hardware (including a circuit unit; circuitry) such as an LSI (Large Scale Integration), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a GPU (Graphics Processing Unit), or may be realized by the cooperation of software and hardware. The program may be stored in the storage unit 200 in advance.

[0022] The storage unit 200 is realized by an HDD (Hard Disk Drive), a flash memory, a ROM, a RAM (Random Access Memory), or the like. In the storage unit 200, for example, in addition to the above-described program, first pattern image information 201 including one or more first pattern images IM1 and second pattern image information 202 including one or more second pattern images IM2 are stored.

[0023] [Regarding the first pattern image IM1] FIG. 3 shows, as an example of the first pattern image IM1, a first pattern image IM1-1 and a first pattern image IM1-2. The first pattern image IM1 is an image showing a stripe pattern in a direction parallel to the X-axis direction, which is the extending direction of the rail L1. As shown in FIG. 3, the width of the stripe pattern of the first pattern image IM1-1 is wider than the width of the stripe pattern of the first pattern image IM1-2. In an example of the present embodiment, the first pattern image information 201 is information including two first pattern images IM1, namely, the first pattern image IM1-1 and the first pattern image IM1-2.

[0024] [Regarding the second pattern image IM2] FIG. 4 shows, as an example of the second pattern image IM2, a second pattern image IM2-1 and a second pattern image IM2-2. The second pattern image IM2 is an image showing a stripe pattern in the Y-axis direction orthogonal to the extending direction of the rail L1. As shown in FIG. 4, the width of the stripe pattern of the second pattern image IM2-1 is wider than the width of the stripe pattern of the second pattern image IM2-2. In an example of the present embodiment, the second pattern image information 202 is information including two second pattern images IM2, namely, the second pattern image IM2-1 and the second pattern image IM2-2.

[0025] [Regarding the first image P1 and the second image P2] The operations of the projection unit 11 and the imaging unit 12 are synchronized. The imaging unit 12 images the rail L1 in a state where the image light of the first pattern image IM1 or the second pattern image IM2 is projected by the projection unit 11, and generates a first image P1. Further, the imaging unit 12 images the rail L1 in a state where the image light of the pattern image is not projected by the projection unit 11, and generates a second image P2.

[0026] In an example shown in FIG. 5, the imaging unit 12 images the rail L1 onto which the image light of the first pattern image IM1-1 is projected by the projection unit 11, and generates the first image P1-1. The imaging unit 12 images the rail L1 onto which the image light of the first pattern image IM1-2 is projected by the projection unit 11, and generates the first image P1-2. The imaging unit 12 images the rail L1 onto which the image light of the second pattern image IM2-1 is projected by the projection unit 11, and generates the first image P1-3. The imaging unit 12 images the rail L1 onto which the image light of the second pattern image IM2-2 is projected by the projection unit 11, and generates the first image P1-4. Further, the imaging unit 12 images the rail L1 in a state where the image light of the pattern image is not projected by the projection unit 11, and generates the second images P2-1 and P2-2.

[0027] In the present embodiment, the projection unit 11 and the imaging unit 12 operate, and it is assumed that the images are generated in the order of the first images P1-1 and P1-2, the second image P2-1, the first images P1-3 and P1-4, and the second image P2-2. In FIG. 5, for convenience of explanation, the viewing angles shown in the first images P1-1 to P1-4 and the second images P2-1 to P2-2 are represented with an offset in the Y-axis direction. However, actually, although the viewing angles shown in the first images P1-1 to P1-4 and the second images P2-1 to P2-2 slightly deviate as the inspection system 1 travels along the rail L1, basically, they coincide or substantially coincide in the Y-axis direction. Further, the projection of the image light of the pattern image by the projection unit 11, the imaging of the rail L1 by the imaging unit 12, and the generation of the first image P1 and the second image P2 are performed simultaneously with the travel of the inspection system 1. For this reason, the viewing angles shown in the first images P1-1 to P1-4 and the second images P2-1 to P2-2 are offset in the X-axis direction. On the other hand, the projection of the image light of the pattern image by the projection unit 11, the imaging of the rail L1 by the imaging unit 12, and the generation of the first image P1 and the second image P2 are performed at a speed sufficiently faster than the travel speed of the inspection system 1. Therefore, in the present embodiment, the viewing angles shown in the first images P1-1 to P1-4 and the second images P2-1 to P2-2 coincide or substantially coincide in the X-axis direction.

[0028] Also, the projection of the image light of the pattern image by the projection unit 11, the imaging of the rail L1 by the imaging unit 12, and the generation of the first images P1-1 to P1-4 and the second images P2-1 to P2-2 are continuously or repeatedly executed at predetermined time intervals.

[0029] [Configuration of the control unit 100] Returning to FIG. 2, the control unit 100 includes, for example, a first noise removal unit 111, a phase conversion unit 112, a second noise removal unit 113, a change amount acquisition unit 114, a coordinate conversion unit 115, a feature point identification unit 116, a synthesis unit 117, and a display control unit 118.

[0030] The first noise removal unit 111 removes noise from the first image P1 based on the first image P1 and the second image P2 generated by the imaging unit 12. The first noise removal unit 111 executes, for example, background noise processing for removing the information of the second image P2 from the information of the first image P1 as noise. Specifically, the first noise removal unit 111 executes background noise processing using the second image P2 that shows an angle of view that matches or substantially matches the angle of view shown in the first image P1. In this example, the first noise removal unit 111 removes the information of the second image P2-1 as noise from the information of the first image P1-1 and the information of the first image P1-2, respectively. Also, the first noise removal unit 111 removes the information of the second image P2-2 as noise from the information of the first image P1-3 and the information of the first image P1-4, respectively.

[0031] The phase conversion unit 112 converts the first image P1 from which noise has been removed by the first noise removal unit 111 into phase information. The phase information is, for example, information indicating the result of Fourier-transforming the first image P1 on which background noise processing has been executed. When there are a plurality of first images P1, the phase conversion unit 112 converts each of the first images P1 into phase information. In this example, the phase conversion unit 112 performs conversion processing to generate phase information PH1 related to the first image P1-1, phase information PH2 related to the first image P1-2, phase information PH3 related to the first image P1-3, and phase information PH4 related to the first image P1-4.

[0032] The second noise removal unit 113 removes, as noise, phase information other than the phase information of the pattern image from the phase information PH. The phase information of the pattern image is, for example, information indicating the result of Fourier-transforming the pattern image. The phase information of the pattern image may be stored in the storage unit 200 in advance, or may be sequentially acquired by the second noise removal unit 113. Hereinafter, it is assumed that the phase information of the pattern image is stored in the storage unit 200 in advance. The second noise removal unit 113 removes, as noise, information in frequency regions other than the frequency region indicated by the phase information of the pattern image from the information in each frequency region indicated by the phase information PH.

[0033] The second noise removal unit 113 performs a process of removing noise from the phase information PH using the phase information of the corresponding pattern image for each phase information PH. Specifically, the second noise removal unit 113 removes, as noise, phase information other than the phase information of the first pattern image IM1-1 from the phase information PH1 of the first image P1-1. The second noise removal unit 113 removes, as noise, phase information other than the phase information of the first pattern image IM1-2 from the phase information PH2 of the first image P1-2. The second noise removal unit 113 removes, as noise, phase information other than the phase information of the second pattern image IM2-1 from the phase information PH3 of the first image P1-3. The second noise removal unit 113 removes, as noise, phase information other than the phase information of the second pattern image IM2-2 from the phase information PH4 of the first image P1-4.

[0034] The change amount acquisition unit 114 acquires the amount of change in the phase based on the phase information PH from which noise has been removed by the second noise removal unit 113. Generally, as long as the projection unit 11 does not project image light by extremely distorting the phase characteristics of the pattern image, the phase of the phase information PH based on the first image P1 generated by the imaging unit 12 is linearly converted with respect to the distance on the image. Therefore, when the phase indicated by the phase information PH does not change linearly, it can be said that it represents the distortion due to the wear of the rail L1. The change amount acquisition unit 114 acquires a value deviated from the linear change of the phase characteristics as the amount of change in the phase. When there are a plurality of pieces of phase information PH, the change amount acquisition unit 114 acquires the change amount for each of the pieces of phase information PH. In this example, the change amount acquisition unit 114 acquires the amount of change in the phase for each of the phase information PH1 to phase information PH4.

[0035] The coordinate conversion unit 115 converts the change amount acquired by the change amount acquisition unit 114 into coordinate information with the imaging unit 12 as the origin. As described above, the viewing angles shown in the first images P1-1 to P1-4 and the second images P2-1 to P2-2 coincide or substantially coincide in the X-axis direction and the Y-axis direction. Therefore, at the timing when the rail L1 is imaged and the first images P1-1 to P1-4 and the second images P2-1 to P2-2 are generated, the positions of the imaging unit 12 coincide or substantially coincide. Here, the coordinates of the plane shown in the first image P1 can be represented in the X-Y coordinate system with the imaging unit 12 as the origin. Further, by referring to the change amount acquired by the change amount acquisition unit 114, the coordinate conversion unit 115 defines the coordinate where the amount of change in the phase is 0 as the origin of the Z-axis, and can add information in the Z-axis direction to the coordinates of the X-Y plane shown in the first image P1. Thereby, the coordinate conversion unit 115 can convert the change amount acquired by the change amount acquisition unit 114 into coordinate information. The coordinate information indicates the coordinates of each part of the surface of the rail L1. Therefore, the shape of the rail L1 is indicated by the coordinate information converted by the coordinate conversion unit 115.

[0036] The feature point specifying unit 116 specifies the feature points of the shape of the rail L1 based on the coordinate information. For example, the feature point specifying unit 116 specifies the range of the X-Y plane where the Z-axis coordinate shown in the coordinate information takes a positive value (that is, the range of the convex portion). Then, the feature point specifying unit 116 specifies the shape of the convex portion in the specified range of the X-Y plane as the feature points of the shape of the rail L1. Further, for example, the feature point specifying unit 116 specifies the range of the X-Y plane where the Z-axis coordinate shown in the coordinate information takes a negative value (that is, the range of the concave portion). Then, the feature point specifying unit 116 specifies the shape of the concave portion in the specified range of the X-Y plane as the feature points of the shape of the rail L1.

[0037] FIG. 6 shows three-dimensional data in which each coordinate indicated by the coordinate information is represented as three-dimensional point cloud data. That is, this three-dimensional data shows the shape of the rail. The three-dimensional data shown in FIG. 6 is based on the coordinate information DT1 converted by the coordinate conversion unit 115 based on the information corresponding to the first images P1-1 to P1-4 and the second images P2-1 to P2-2. In this example, the three-dimensional data is the shape of the rail L1 based on the coordinate information DT1, and represents the shape of the rail L1 shown from the left side. The feature point specifying unit 116 specifies the feature point PT1 of the shape of the rail L1 at the end in the +X axis direction among the shapes of the rail L1 shown in the coordinate information DT1 based on the coordinate information DT1.

[0038] The combining unit 117 combines a plurality of pieces of coordinate information based on the feature point PT. Specifically, the combining unit 117 combines a plurality of pieces of coordinate information by regarding the feature points PT with strong correlation among the feature points PT shown in the plurality of pieces of coordinate information as the same feature point PT.

[0039] In the following description, the coordinate information converted by the coordinate conversion unit 115 based on the first images P1-1 to P1-4 and the second images P2-1 to P2-2 generated at the first timing is defined as coordinate information DT1. Also, the coordinate information converted by the coordinate conversion unit 115 based on the first images P1-1 to P1-4 and the second images P2-1 to P2-2 generated at the second timing is defined as coordinate information DT2. Further, the coordinate information converted by the coordinate conversion unit 115 based on the first images P1-1 to P1-4 and the second images P2-1 to P2-2 generated at the third timing is defined as coordinate information DT3. The combining unit 117 combines a plurality of coordinate information DTs of the coordinate information DT1 to DT3.

[0040] The first timing, the second timing, and the third timing occur over time in the order of description. Also, a part of the viewing angle of the first images P1-1 to P1-4 and the second images P2-1 to P2-2 generated at the first timing and a part of the viewing angle of the first images P1-1 to P1-4 and the second images P2-1 to P2-2 generated at the second timing overlap at least partially. Further, a part of the viewing angle of the first images P1-1 to P1-4 and the second images P2-1 to P2-2 generated at the second timing and a part of the viewing angle of the first images P1-1 to P1-4 and the second images P2-1 to P2-2 generated at the third timing overlap at least partially.

[0041] The combining unit 117 combines coordinate information DTs that are temporally continuous with each other among the plurality of coordinate information DTs. In this example, the combining unit 117 combines the coordinate information DT1 and the coordinate information DT2, and combines the coordinate information DT obtained by combining the coordinate information DT1 and the coordinate information DT2 with the coordinate information DT3. For example, for two pieces of coordinate information DT, the combining unit 117 moves or rotates the feature points PT indicating the shapes of the concave and convex portions shown in each coordinate information DT in the XYZ axis directions to identify the position where the correlation of the shapes is the strongest. At the identified position, the combining unit 117 adjusts the coordinates of the other coordinate information DT to match the coordinates of the reference coordinate information DT among the two pieces of coordinate information DT so that the feature points PT overlap, and combines the two pieces of coordinate information DT.

[0042] FIG. 7 shows three-dimensional data based on coordinate information DT1, coordinate information DT2, and coordinate information DT3. As described above, the feature point specifying unit 116 specifies a feature point PT1 at the end in the +X-axis direction of the rail L1 shown in the coordinate information DT1 based on the coordinate information DT1. Further, the feature point specifying unit 116 specifies a feature point PT2 at the end in the -X-axis direction of the shape of the rail L1 shown in the coordinate information DT2 and a feature point PT3 at the end in the +X-axis direction based on the coordinate information DT2. Further, the feature point specifying unit 116 specifies a feature point PT4 at the end in the -X direction of the shape of the rail L1 shown in the coordinate information DT3 based on the coordinate information DT3.

[0043] The combining unit 117 specifies that the feature point PT1 shown in the coordinate information DT1 and the feature point PT2 shown in the coordinate information DT2 are feature points PT with a strong correlation. Then, the combining unit 117 specifies the position where the correlation between the shape of the feature point PT1 and the shape of the feature point PT2 is the strongest. The combining unit 117 adjusts the coordinates shown in the coordinate information DT2 according to the coordinates shown in the coordinate information DT1 so that the feature points PT1 and PT2 overlap at the specified position, and combines the coordinate information DT1 and the coordinate information DT2. Further, the combining unit 117 specifies that the feature point PT3 shown in the coordinate information DT2 and the feature point PT4 shown in the coordinate information DT3 are feature points PT with a strong correlation. Then, the combining unit 117 specifies the position where the correlation between the shape of the feature point PT3 and the shape of the feature point PT4 is the strongest. The combining unit 117 adjusts the coordinates shown in the coordinate information DT3 according to the coordinates shown in the adjusted coordinate information DT2 so that the feature points PT3 and PT4 overlap at the specified position, and combines the coordinate information DT2 and the coordinate information DT3.

[0044] [Regarding the output of inspection results] The user of the inspection system 1 operates the reception unit 13 to refer to the inspection result of the wear of the rail L1 by the inspection device 10. The user designates, for example, the range for which the inspection result is to be referred to among the inspection target ranges where the wear of the rail L1 has been inspected by the inspection device 10. The designation of the range may be performed, for example, by designating the distance starting from the inspection start position, or by designating the business kilometers from the starting point.

[0045] Based on the user operation received by the reception unit 13, the display control unit 118 causes the display unit 14 to display the shape information indicating the shape of the wear existing in the designated inspection target range. The shape information is, for example, a statistical value indicating the shape of the wear. The statistical value indicating the shape of the wear is, for example, the maximum value, minimum value, and average value in the Z-axis direction of the convex portion or concave portion generated on the rail L1 due to the wear. In addition, the statistical value indicating the shape of the wear includes the repeating length of the repeatedly existing wear (that is, wavy wear).

[0046] The display control unit 118 associates, for example, the plurality of coordinate information DTs synthesized by the synthesis unit 117 with the inspection target range by the inspection device 10. The display control unit 118 may, for example, set the coordinates of the origin among the coordinates indicated by the synthesized coordinate information DT as the coordinates of the start position of the inspection target range, and the coordinate farthest in the X-axis direction from the origin as the coordinates of the end position of the inspection target range. The display control unit 118 identifies the feature points PT existing in the inspection target range designated by the user based on the synthesized coordinate information DT, the inspection target range designated by the user, and the identification result of the feature point identification unit 116. The display unit 14 refers to the coordinate information DT of the identified feature points PT and extracts the statistical values indicating the shape of the wear.

[0047] As shown in FIG. 8, the display control unit 118 causes the display unit 14 to display a result image RT1 showing a list of statistical values indicating the shape of the wear related to the inspection target range designated by the user. [Operation Flow] Hereinafter, with reference to FIG. 9, the operation of the inspection device 10 will be described. The flowchart shown in FIG. 9 is executed when the inspection device 10 inspects the wear occurring on the rail L1.

[0048] First, the projection unit 11 projects the image light of the pattern image onto the rail L1 (step S100). Next, the imaging unit 12 images the rail L1 onto which the pattern image is projected by the projection unit 11 and generates a first image P1 (step S102). Next, the projection unit 11 stops projecting the image light of the pattern image onto the rail L1 (step S104). Next, the imaging unit 12 images the rail L1 onto which the pattern image is not projected and generates a second image P2 (step S106).

[0049] Next, the first noise removal unit 111 removes noise from the first image P1 based on the first image P1 and the second image P2 generated by the imaging unit 12 (step S108). Specifically, the first noise removal unit 111 executes background noise processing for removing the information of the second image P2 from the information of the first image P1 as noise. When a plurality of first images P1 are generated using a plurality of pattern images, the first noise removal unit 111 executes background noise processing for each first image P1 using a second image P2 that shows an angle of view that matches or substantially matches the angle of view shown in the first image P1. Next, the phase conversion unit 112 converts the first image P1 from which noise has been removed by the first noise removal unit 111 into phase information PH (step S110). When a plurality of first images P1 are generated using a plurality of pattern images, the phase conversion unit 112 generates phase information PH for each of the plurality of first images P1, respectively.

[0050] Next, the second noise removal unit 113 removes, as noise, the phase information other than the phase information of the pattern image from the phase information PH (step S112). When a plurality of phase information PH is generated, the second noise removal unit 113 removes noise for each of the plurality of phase information PH by using the phase information of the corresponding pattern image. Next, the change amount acquisition unit 114 acquires the amount of change in the phase based on the phase information PH from which noise has been removed by the second noise removal unit 113 (step S114). When the phase indicated by the phase information PH does not change linearly with respect to the distance on the image, the change amount acquisition unit 114 acquires, as the amount of change in the phase, a value deviated from the linear change in the phase characteristics, assuming that it represents the distortion due to the wear of the rail L1. When a plurality of phase information PH is generated, the change amount acquisition unit 114 acquires the change amount for each of the plurality of phase information PH.

[0051] Next, the coordinate conversion unit 115 converts the change amount acquired by the change amount acquisition unit 114 into coordinate information with the imaging unit 12 as the origin (step S116). The coordinate conversion unit 115 represents the coordinates of the plane shown in the first image P1 with the imaging unit 12 as the origin in the X-Y coordinate system, defines the coordinates where the change amount of the phase is 0 as the origin of the Z axis, and converts the change amount into coordinate information. Next, the feature point identification unit 116 identifies the feature points PT of the shape of the rail L1 based on the coordinate information (step S118). The feature point identification unit 116 identifies the shape of the identified convex portion or concave portion as the feature point PT of the shape of the rail L1.

[0052] Next, the synthesizing unit 117 synthesizes a plurality of pieces of coordinate information based on the feature points PT (step S120). The synthesizing unit 117 synthesizes the coordinate information DT that is temporally continuous among the plurality of pieces of coordinate information DT. The synthesizing unit 117 synthesizes the plurality of pieces of coordinate information by treating the feature points PT with a strong phase difference among the feature points PT shown in the plurality of pieces of coordinate information as the same feature points PT. Next, based on the operation of the user received by the receiving unit 13, the display control unit 118 causes the display unit 14 to display a statistical value indicating the shape of wear existing in the designated inspection target range (step S122). The display control unit 118 causes the display unit 14 to display, for example, a result image RT1 showing a list of statistical values indicating the shape of wear related to the inspection target range designated by the user.

[0053] [Effects of the Embodiment] According to the above embodiment, the following effects can be obtained. (1) The synthesizing unit 117 synthesizes a plurality of pieces of coordinate information DT in which the shape of the rail L1 is shown. Thereby, the inspection device 10 can synthesize a plurality of pieces of coordinate information DT based on the feature points PT of the shape of the rail L1 and continuously inspect the wear of the rail L1.

[0054] (2) The display unit 14 displays a result image RT1 showing shape information indicating the shape of wear existing in the range of the rail L1 indicated by the operation of the user. The shape information is, for example, a statistical value indicating the shape of wear. Thereby, the user can refer to the statistical value of the designated inspection range among the information related to the wear of the continuously inspected rail L1.

[0055] (3) The pattern image is the first pattern image IM1 showing a stripe pattern in a direction parallel to the extending direction of the rail L1, or the second pattern image IM2 showing a stripe pattern in a direction orthogonal to the extending direction. Here, the change amount acquisition unit 114 can acquire the change amount more accurately by using the phase information PH based on the pattern images of stripe patterns in a plurality of directions than the phase information PH based on the pattern image of only the stripe pattern in one direction. The change amount acquisition unit 114 uses the phase information PH based on the first pattern image IM1 of the stripe pattern in the direction parallel to the extending direction of the rail L1 and the phase information PH based on the second pattern image IM2 of the stripe pattern in the direction parallel to the extending direction of the rail L1 of the rail L1, and can inspect the wear of the rail L1 more accurately.

[0056] (4) The imaging unit 12 generates a plurality of first images P1 by using a plurality of first pattern images IM1 with different stripe widths respectively, or a plurality of second pattern images IM2 with different stripe widths respectively. The first noise removal unit 111 removes noise from the first image P1 based on the first image P1 with an angle of view that coincides with or substantially coincides with the angle of view shown in the first image P1. The coordinate conversion unit 115 converts the coordinate information for each of the plurality of phase information PH based on the plurality of first images P1 with coinciding or substantially coinciding angles of view.

[0057] Here, when the change amount acquisition unit 114 acquires the displacement amount using a pattern image with a uniform stripe pattern, it is required to use a plurality of first images P1. This is because the phase conversion unit 112 needs to comprehensively acquire the phase information PH of the inspection object shown in the first image P1 by Fourier transform. Therefore, it is necessary to capture images while slightly changing the projection position of the pattern image and use the plurality of generated first images P1. On the other hand, when using pattern images with different widths of a part or all of the stripe patterns, compared with the case of using a pattern image with a uniform stripe pattern, the phase information PH of the inspection object can be comprehensively acquired with a smaller number of first images P1. This is because when the phase conversion unit 112 comprehensively acquires the phase information PH of the inspection object shown in the first image P1, by using pattern images with different widths, Fourier transform can be performed efficiently. When using a smaller number of first images P1, the number of times of the conversion process of the phase information PH by the phase conversion unit 112, the noise removal process of the second noise removal unit 113, and the change amount acquisition process of the change amount acquisition unit 114 can be reduced. According to such a configuration, the inspection device 10 can efficiently inspect the wear of the rail L1 compared with the case of using a pattern image with a uniform stripe pattern.

[0058] The above embodiments may be modified as follows. Note that the above embodiments and the following separate examples may be combined with each other as long as they do not conflict technically. 〇 As shown in FIG. 10, the display control unit 118 may cause the display unit 14 to display a result image RT2 that combines the second image P2 indicating the range of the rail L1 instructed by the user's operation and the result image RT1. According to such a configuration, the user can confirm the statistical value indicating the shape of the wear and the state of the second image P2 of the range of the rail L1 instructed by the user's operation together.

[0059] Although the inspection system 1 has been described as performing correction and inspection simultaneously during a single run, it is not limited to this. The inspection system 1 may perform correction and inspection separately. For example, the inspection system 1 performs the run related to correction and the run related to inspection separately. Further, the inspection device 10 may inspect the wear occurring on the rail L1 after being corrected by the rail head correction device.

[0060] Although the pattern images projected by the projection unit 11 onto the rail L1 have been described as being two each of the first pattern images IM1-1, IM1-2 and the second pattern images IM2-1, IM2-2, it is not limited to this. The pattern image projected by the projection unit 11 onto the rail L1 may be one, or may be a number more than two. Further, the pattern image is not limited to the stripe pattern in the direction parallel to the X-axis direction which is the extending direction of the rail L1 and the stripe pattern in the Y-axis direction orthogonal to the extending direction of the rail L1, and may show stripe patterns in other directions. Also, the width of the stripe pattern shown in the pattern image may be uniform, or may be partially different. In this case, the width of the stripe pattern may be suitably changed in part so that the efficiency of the Fourier transform by the phase conversion unit 112 is good.

[0061] When the viewing angles of the first images P1-1 to P1-4 and the second images P2-1 to P2-2 do not match depending on the running speed of the inspection system 1, the imaging unit 12 may generate a second image P2 with a viewing angle corresponding to the first image P1 for each first image P1. Thereby, the first noise removal unit 111 can appropriately perform the process of removing the background noise of the first image P1.

[0062] When the first image P1 does not contain background noise or contains little background noise depending on the environment in which the inspection system 1 runs, the imaging unit 12 may not image and generate the second image P2. In this case, the control unit 100 may not include the first noise removal unit 111.

[0063] 〇The inspection device 10 may include a plurality of imaging units 12, where one imaging unit 12 images the rail L1 from above the right side surface, and the other imaging unit 12 images the rail L1 from above the left side surface. In this case, the control unit 100 synthesizes the image captured from above the right side surface and generated with the image captured from above the left side surface and generated, and executes subsequent processing using the synthesized image as the first image P1. As shown in FIG. 11, the inspection device 10 can inspect not only the shape of the wear generated on the surface of the rail L1 but also the shape of the wear generated on the side surface of the rail L1. Further, the inspection system 1 may include two inspection devices 10, namely, an inspection device 10 for inspecting the right rail and an inspection device 10 for inspecting the left rail.

[0064] 〇The display control unit 118 may cause the display unit 14 to display, as shape information, three-dimensional data indicating the shape of the wear existing within the specified inspection target range based on the operation of the user received by the reception unit 13. In this case, the display control unit 118 generates three-dimensional data representing the shape of the rail L1 within the inspection target range specified by the user based on the coordinate information DT and causes the display unit 14 to display it. According to such a configuration, the user can easily grasp the shape of the wear by referring to the three-dimensional data indicating the shape of the wear within the specified inspection range.

[0065] 〇The inspection device 10 may include, instead of (or in addition to) the display unit 14, a communication unit as an output unit. In this case, the communication unit transmits and receives information to and from a device connected to the inspection device 10 via a network. Further, when the inspection device 10 includes a communication unit, the control unit 100 includes a communication control unit that controls the communication of the communication unit. The communication control unit controls various communications of the communication unit. According to such a configuration, the user can refer to the inspection result of the inspection device 10 via a device connected to the inspection device 10 via a network.

Explanation of Reference Numerals

[0066] 1…Inspection system, 10…Inspection device, 11…Projection unit, 12…Imaging unit, 13…Reception unit, 14…Display unit, 20…Drive cart, 100…Control unit, 111…First noise removal unit, 112…Phase conversion unit, 113…Second noise removal unit, 114…Change amount acquisition unit, 115…Coordinate conversion unit, 116…Feature point identification unit, 117…Synthesis unit, 118…Display control unit, 200…Memory unit, 201…First pattern image information, 202…Second pattern image information, DT, DT1, DT2, DT3…Coordinate information, IM1, IM1-1, IM1-2…First pattern image, IM2, IM2-1, IM2-2…Second pattern image, L1…Rail, P1, P1-1, P1-2, P1-3, P1-4…First image, P2, P2-1, P2-2…Second image, PH, PH1, PH2, PH3, PH4…Phase information, PT, PT1, PT2, PT3, PT4…Feature point, RT1, RT2…Result image.

Claims

1. A projection unit that projects image light of a pattern image onto an inspection target for wear; An imaging unit that captures the inspection target onto which the image light of the pattern image is projected to generate a first image, and captures the inspection target onto which the image light of the pattern image is not projected to generate a second image; A first noise removal unit that removes noise from the first image based on the first image and the second image; A phase conversion unit that converts the first image from which noise has been removed by the first noise removal unit into phase information; A second noise removal unit that removes, as noise, phase information other than the phase information of the pattern image from the phase information; A change amount acquisition unit that acquires a change amount of the phase based on the phase information from which noise has been removed by the second noise removal unit; A coordinate conversion unit that converts the change amount into coordinate information with the imaging unit as the origin; A feature point specifying unit that specifies feature points of the shape of the inspection target based on the coordinate information; A synthesis unit that synthesizes a plurality of the coordinate information based on the feature points; An inspection apparatus, characterized by comprising the above.

2. A reception unit that receives a user's operation; The inspection apparatus according to claim 1, further comprising an output unit that outputs shape information indicating the shape of the wear existing in the range of the inspection target indicated by the user's operation. The inspection apparatus according to claim 1.

3. The shape information is a statistical value indicating the shape of the wear. The inspection apparatus according to claim 2.

4. The shape information is three-dimensional data indicating the shape of the wear. The inspection apparatus according to claim 2 or 3.

5. The pattern image is a first pattern image showing a stripe pattern in a direction parallel to the stretching direction of the inspection target, or a second pattern image showing a stripe pattern in a direction orthogonal to the stretching direction. The inspection apparatus according to any one of claims 1 to 4.

6. The imaging unit generates a plurality of the first images using a plurality of the first pattern images having different widths of the stripe patterns or a plurality of the second pattern images having different widths of the stripe patterns. The first noise removal unit removes noise from the first image based on the second image having an angle of view that matches or substantially matches the angle of view shown in the first image. The coordinate conversion unit converts the coordinate information for each of the plurality of phase information based on the plurality of the first images having matching or substantially matching angles of view. The inspection apparatus according to claim 5.

Images