Contact wire inspection device and contact wire inspection method

Abstract

A trolley wire inspection device and a trolley wire inspection method are provided that accurately detect worn areas of a trolley wire. [Solution] A line sensor image generating unit 30 generates a line sensor image from an image captured by a line sensor 22. A worn area extraction image generating unit 32 extracts a worn area of ​​a trolley wire by performing image processing according to a plurality of image processing execution procedures M registered in an image processing execution procedure storage unit 33, scans outward from the extracted worn area, and corrects the worn area by setting the position where the brightness value becomes equal to or less than a preset brightness value as the boundary of the worn area, thereby generating a plurality of worn area extraction images corresponding to each of the plurality of image processing execution procedures M. A worn area extraction image evaluating unit 34 selects the worn area extraction image with the highest evaluation value from the plurality of worn area extraction images. A trolley wire deviation calculating unit 35 and a trolley wire remaining diameter calculating unit 36 ​​calculate the deviation and remaining diameter of the trolley wire based on the selected worn area extraction image.

Description

[Technical field]

[0001] The present invention relates to a trolley wire inspection device and a trolley wire inspection method. [Background technology]

[0002] When an electric railway vehicle travels on a track, it obtains power by receiving electricity from a contact wire installed above the track through a current collector such as a pantograph. Each time an electric railway vehicle passes, the current collector slides against the underside of the contact wire. For this reason, if an electric railway vehicle is continuously operated, the contact wire gradually wears and eventually breaks. Therefore, a wear limit is set for the contact wire, and if the remaining diameter of the contact wire falls below a controlled value, the contact wire is replaced with a new one. Meanwhile, since the contact part of the current collector also wears, the contact wire is installed with a zigzag deviation perpendicular to the rail to prevent the contact part from concentrating in one place, and the amount of this deviation is also controlled. It is very time-consuming for workers to manually inspect and measure the contact wire.

[0003] For example, Patent Document 1 discloses an automatic inspection device that includes a light that illuminates a worn area located below a trolley wire above an electric railway vehicle, and a line sensor that captures an image of the worn area of ​​the trolley wire illuminated by the light (the sliding surface with which the pantograph contacts). More specifically, the line sensor is installed so that the scanning line faces upward and crosses the trolley wire, and the images captured by the line sensor are arranged in chronological order to generate a line sensor image. Then, image processing is applied to this line sensor image, and the deviation and remaining diameter of the trolley wire are calculated using known data on the specifications of the trolley wire, such as the height and thickness of the trolley wire. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5287177 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in devices such as those described above, there may be differences in the brightness of the worn area of ​​the trolley wire in the line sensor image due to lighting, the condition of the worn area of ​​the trolley wire, the shooting environment, etc., which results in the problem that the worn area cannot be accurately acquired.

[0006] Therefore, an object of the present invention is to provide a trolley wire inspection device and a trolley wire inspection method that are capable of accurately detecting worn areas of a trolley wire. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention employs the following means. That is, a trolley wire inspection device according to a first aspect of the present invention is a trolley wire inspection device that includes a line sensor that captures a trolley wire, and inspects the trolley wire based on an image captured by the line sensor as an input image, the trolley wire inspection device including a line sensor image generation unit that generates a line sensor image by arranging the input images in time series, an image processing execution procedure storage unit in which, when sequentially executing a plurality of image processing functions on the line sensor image, the execution orders of the image processing functions are registered as a plurality of image processing execution procedures, and the trolley wire inspection device executes the plurality of image processing functions using the line sensor image as an input according to each of the plurality of image processing execution procedures, thereby detecting the presence or absence of the trolley wire. the wear area extraction image generation unit extracts a worn area of ​​the trolley wire, corrects the worn area by scanning outward from the extracted wear area of ​​the trolley wire and setting the position where the brightness value becomes equal to or lower than a predetermined brightness value as the boundary of the wear area, and generates a plurality of wear area extraction images corresponding to each of the plurality of image processing execution procedures; a wear area extraction image evaluation unit calculates an evaluation value of each of the plurality of wear area extraction images and selects the wear area extraction image with the highest evaluation value; and a trolley wire inspection unit calculates either or both of the remaining diameter and deviation of the trolley wire based on the selected wear area extraction image with the highest evaluation value.

[0008] In addition, the trolley wire inspection device of the second invention is characterized in that each of the plurality of image processing execution procedures is registered to be executed in this order: zero or more contrast adjustment processes, zero or more background / noise removal processes, one or more binarization processes, and zero or more interpolation processes.

[0009] In addition, the trolley wire inspection device of the third invention is characterized in that each of the multiple image processing execution procedures is associated with a priority and stored, and when the same evaluation value is calculated for multiple wear area extraction images, the wear area extraction image corresponding to the image processing execution procedure with the highest priority is selected as the wear area extraction image with the highest evaluation value.

[0010] In addition, the trolley wire inspection device of the fourth invention is characterized in that the wear area extraction image evaluation unit calculates the number of wear areas for each of the multiple wear area extraction images, and calculates the evaluation value so that the evaluation value is high when the difference between the number of wear areas and the actual number of the trolley wires is small.

[0011] In addition, the trolley wire inspection device of the fifth invention is characterized in that the wear area extraction image evaluation unit calculates a trolley wire likelihood, which is an index indicating that the wear area has image features similar to the trolley wire, for each of the multiple wear area extraction images, and calculates the evaluation value so that the evaluation value is high when the trolley wire likelihood is high.

[0012] In addition, the trolley wire inspection device of the sixth invention is characterized in that the image processing execution procedure memory unit registers the image processing execution procedure corresponding to each of a plurality of different environments when the image is captured by the line sensor, and further includes an environment determination unit that determines the environment in which the input image was captured based on the line sensor image, and the wear area extraction image generation unit generates the wear area extraction image according to the image processing execution procedure corresponding to the determined environment.

[0013] In addition, a trolley wire inspection method according to a seventh invention is a trolley wire inspection method in which an image captured by a line sensor that captures a trolley wire is used as an input image and the trolley wire is inspected based on the input image, and is characterized in that it includes arranging the input images in chronological order to generate a line sensor image, when sequentially executing a plurality of image processing functions on the line sensor image, the execution order of which is registered as a plurality of image processing execution procedures, and extracting a worn area of ​​the trolley wire by executing the plurality of image processing functions using the line sensor image as an input according to each of the plurality of image processing execution procedures, correcting the worn area by scanning outward from the extracted worn area of ​​the trolley wire and setting the position where the brightness value becomes equal to or lower than a predetermined brightness value as the boundary of the worn area, and generating a plurality of wear area extraction images corresponding to each of the plurality of image processing execution procedures, calculating an evaluation value of each of the plurality of wear area extraction images and selecting the wear area extraction image with the highest evaluation value, and calculating either or both of the remaining diameter and deviation of the trolley wire based on the selected wear area extraction image with the highest evaluation value. Effect of the Invention

[0014] According to the present invention, the worn area of ​​the trolley wire can be accurately detected even if a difference in brightness occurs in the worn area. [Brief description of the drawings]

[0015] [Figure 1] 1 is an explanatory diagram showing a running environment of an electric railway vehicle equipped with a trolley wire inspection device according to an embodiment of the present invention. FIG. [Diagram 2] 1 is a block diagram showing a functional configuration of a trolley wire inspection device according to an embodiment of the present invention. [Diagram 3] 1 is a schematic diagram showing an example of a line sensor image generated based on an image captured by a line sensor of the trolley wire inspection device according to this embodiment. FIG. [Figure 4] 1 is a schematic diagram showing an example of a worn area extraction image temporarily acquired by the trolley wire inspection device according to this embodiment. FIG. [Diagram 5]1 is a schematic diagram showing an example of a worn area extraction image finally acquired by the trolley wire inspection device according to this embodiment. FIG. [Figure 6] 2 is an explanatory diagram of an image processing execution procedure storage unit of the trolley wire inspection device of the present embodiment. FIG. [Figure 7] 4A is an explanatory diagram of a trolley wire deviation calculation unit of the trolley wire inspection device, and FIG. 4B is an explanatory diagram of a trolley wire remaining diameter calculation unit of the trolley wire inspection device. [Figure 8] 5 is a flowchart for explaining the operation of the trolley wire inspection method by the trolley wire inspection device according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is an explanatory diagram showing a traveling environment of an inspection vehicle 1 that inspects a contact wire and is equipped with a contact wire inspection device 20 according to the present embodiment. In FIG. 1, the inspection vehicle 1 travels on a pair of tracks 2 laid on the ground. On the side of the tracks 2, a plurality of utility poles 3 are erected at intervals along the tracks 2. The utility poles 3 are provided with beams 5 and curved pull fittings 6. Above the beams 5, a feeder 4, which is a power line for supplying power to the inspection vehicle 1, is provided so as to extend along the direction R of the tracks 2 and to be supported by the beams 5. Below the beams 5 and the curved pull fittings 6, a suspension line 7 that suspends a contact wire 9, which will be described next, is provided so as to extend along the direction R of the tracks 2 and to be supported by the beams 5 and the curved pull fittings 6. A plurality of hangers 8 are provided so as to be suspended from the suspension line 7 at approximately regular intervals in the direction R of the tracks 2.

[0017] The contact wire 9 is suspended from these multiple hangers 8 with a constant tension, and is provided below the suspension wire 7 so as to be approximately parallel to the suspension wire 7. Power is supplied to the contact wire 9 from the feeder wire 4 via a feeder branch line (not shown). A current collector 1b such as a pantograph is provided on the upper surface 1a of the inspection vehicle 1, and power is supplied to the inspection vehicle 1 from the contact wire 9 when the current collector 1b comes into contact with the contact wire 9 while the inspection vehicle 1 is traveling.

[0018] For example, one or two trolley wires 9 are provided running parallel to the pair of tracks 2. When the trolley wire 9, which is the source of power supply, moves to the next adjacent trolley wire 9 in the extending direction R of the tracks 2 while an electric railway vehicle such as the inspection vehicle 1 is running, in order to prevent a section from being generated where power is not supplied, the trolley wire 9 is provided so as to overlap with another adjacent trolley wire 9 at its end along the extending direction R of the tracks 2. For this reason, in this embodiment, there may be a section where up to four trolley wires 9 are provided overlapping with respect to the pair of tracks 2. In addition, when photographing a branch point of the trolley wire 9 corresponding to a branch of the tracks, a number of trolley wires 9 greater than that in a normal section may be photographed.

[0019] If the contact wire 9 were installed parallel to the tracks 2, the contact area of ​​the current collector 1b with the contact wire 9 would be limited, which could cause uneven wear and damage to the limited area of ​​the current collector 1b. To prevent this, the contact wire 9 is installed so as to gently zigzag along the direction R of the track 2. The deviation of the contact wire 9, which is the deviation of the contact wire 9 from the center between the pair of tracks 2 caused by this meandering, is strictly controlled.

[0020] Each time an electric railway vehicle, such as the inspection vehicle 1, passes, the current collector 1b slides against the underside of the trolley wire 9. For this reason, when the electric railway vehicle is continuously operated, the trolley wire 9 gradually wears and eventually breaks. Therefore, a wear limit is set for the trolley wire 9, and when the remaining diameter of the trolley wire 9 falls below the control value, the trolley wire 9 is replaced with a new one.

[0021] The trolley wire inspection device 20 in this embodiment inspects the trolley wire 9 by measuring the remaining diameter and deviation of the trolley wire 9. The trolley wire inspection device 20 includes a light 21, a line sensor 22, and a control device 23. The light 21 is provided to irradiate light upward onto the upper surface 1a of the inspection vehicle 1. When the trolley wire 9 is imaged by the line sensor 22 described next, the worn area on the underside of the trolley wire 9, which has been worn down to a flat shape due to the sliding of the current collector 1b, is imaged so as to be displayed as a bright area by reflecting the light of the light 21.

[0022] The line sensor 22, like the lighting 21, is provided on the upper surface 1a of the inspection vehicle 1. The line sensor 22 is a camera that captures an image composed of one pixel in the vertical direction and multiple pixels in the horizontal direction, for example, 8192 pixels. In this embodiment, the line sensor 22 captures a grayscale image, so that each pixel has one luminance value.

[0023] The line sensor 22 is disposed vertically upward and such that the direction 22b of the scanning line 22a is perpendicular to the extending direction R of the track 2 and is the same as the extending direction of the sleepers (not shown). This allows the scanning line 22a of the line sensor 22 to cross the trolley wire 9. The line sensor 22 captures images of the trolley wire 9 continuously at short time intervals while the inspection vehicle 1 is traveling. The images captured by the line sensor 22 are transmitted to the control device 23 as input images. The control device 23 is an information processing device such as a personal computer. The control device 23 is mounted on the inspection vehicle 1.

[0024] Fig. 2 is a block diagram showing the functional configuration of the trolley wire inspection device 20 according to this embodiment. In Fig. 2, the control device 23 includes a line sensor image generating unit 30, an environment determining unit 31, a worn area extraction image generating unit 32, an image processing execution procedure storing unit 33, a worn area extraction image evaluating unit 34, a trolley wire deviation calculating unit (trolley wire inspection unit) 35, and a trolley wire remaining diameter calculating unit (trolley wire inspection unit) 36.

[0025] The line sensor image generating unit 30 receives the input image from the line sensor 22, and arranges the input image vertically in time series, for example, 1000 lines, to generate a line sensor image.

[0026] 3 is a schematic diagram showing an example of a line sensor image generated based on an image captured by the line sensor of the trolley wire inspection device according to this embodiment. In the line sensor image 50, the horizontal direction X is the direction 22b of the scanning line 22a of the line sensor 22, and the vertical direction Y is the time series direction, i.e., the direction in which the input images are arranged.

[0027] In the line sensor image 50 shown in FIG. 3, the trolley wire 9 is captured in the foreground. When the trolley wire 9 is new, it has a substantially circular cross section, and its lower side is worn away by the sliding of the current collector 1b, forming a flat worn area 9a. The worn area 9a is illuminated by the lighting 21, and is captured brightly. On both sides of the worn area 9a of the trolley wire 9, the surface 9b of the trolley wire 9 is captured, which curves outward from the width direction end of the worn area 9a and continues upward. In the line sensor image 50 in FIG. 3, a portion where the trolley wire 9 is bent by the bent pulling fitting 6 is captured. In addition, due to the lighting, the state of the worn area of ​​the trolley wire, the shooting environment, etc., a brightness difference may occur in the worn area 9a, resulting in dark areas 9c and 9d with partially low brightness.

[0028] The overhead wire 7 is imaged behind the contact wire 9. Further behind the overhead wire 7, the feeder wire 4 and the beam 5 and curved metal fitting 6 that support them are imaged. The beam 5 and the curved metal fitting 6 are imaged as thinner than they actually are due to the effect of the imaging interval of the line sensor 22. The sky 10 is captured as a background to the contact wire 9, the overhead wire 7, the feeder 4, the beam 5, and the curved pulley 6. Since this line sensor image 50 was captured in bright daylight, the sky 10 is displayed brightly with a high luminance value.

[0029] The line sensor image generating unit 30 generates such a line sensor image 50 and transmits it to the wear area extraction image generating unit 32.

[0030] The environment determination unit 31 determines the environment in which the input image was captured based on the line sensor image 50 generated by the line sensor image generation unit 30. The environment determination unit 31 determines five types of environments: night or tunnel, dark daytime, bright daytime, the moment of entering a tunnel in daytime, and other situations. For this determination, the environment determination unit 31 calculates a histogram of the line sensor image 50 and calculates the average value, the mode, the second most frequent luminance value, and the third most frequent luminance value. After that, the environment is determined by comparing each of the calculated values ​​with a night determination threshold, a dark daytime determination threshold, and a bright daytime determination threshold that are set in advance, as follows:

[0031] The environment determination unit 31 determines that the environment corresponding to the line sensor image 50 is night or a tunnel when all of the following determination formulas are simultaneously satisfied. 0 ≦ average value ≦ night judgment threshold 0 ≦ Mode ≦ Night judgment threshold 0 ≦ second most frequent luminance value ≦ night threshold 0 ≦ 3rd most frequent luminance value ≦ nighttime threshold

[0032] The environment determination unit 31 determines that the environment corresponding to the line sensor image 50 is dark daytime when all of the following determination formulas are simultaneously satisfied. Nighttime threshold < average value ≦ dark daytime threshold Nighttime threshold < Mode value ≦ Dark daytime threshold Night threshold < second most frequent luminance value ≦ dark day threshold Night threshold < 3rd most frequent luminance value ≦ Dark day threshold

[0033] The environment determination unit 31 determines that the environment corresponding to the line sensor image 50 is bright daytime when all of the following determination formulas are simultaneously satisfied. Bright daylight threshold < average value Bright daylight threshold < mode Bright daylight threshold < second most frequent luminance value Bright daylight threshold < 3rd most frequent luminance value

[0034] When all of the following determination formulas are simultaneously satisfied, the environment determination unit 31 determines that the environment corresponding to the line sensor image 50 is daytime and the moment when the vehicle enters a tunnel. Night threshold < average value ≦ maximum brightness value (e.g., 255) 0 ≦ Mode ≦ Night judgment threshold 0 ≦ second most frequent luminance value ≦ night threshold 0 ≦ 3rd most frequent luminance value ≦ nighttime threshold

[0035] If the environment does not fall into any of the above-mentioned environments, the environment determination unit 31 determines that the environment is other. The environment determination unit 31 transmits the determined environment to the wear area extraction image generation unit 32 .

[0036] The wear area extraction image generation unit 32 receives the line sensor image 50 from the line sensor image generation unit 30 and the judgment result (environment) from the environment judgment unit 31, and performs various image processing functions on the line sensor image 50 to extract the wear area 9a of the trolley wire 9 and generate a wear area extraction image.

[0037] The wear area extraction image generating unit 32 includes an image processing unit 40 and a post-processing unit 41. The image processing unit 40 is configured to be able to selectively execute various image processing functions. The image processing unit 40 includes a contrast adjustment processing unit 40A, a background / noise removal processing unit 40B, a binarization processing unit 40C, an interpolation processing unit 40D, and a wear area correction unit 40E.

[0038] The contrast adjustment processing unit 40A is configured to selectively execute one or more image processing functions for adjusting the gradation of an image. As the contrast adjustment processing, for example, a gamma correction processing that corrects the gradation of an image to an appropriate curve according to a gamma value, or a processing that adjusts the gradation by normalizing a luminance value can be applied. Note that the contrast adjustment processing included in the contrast adjustment processing unit 40A is not limited to the above-mentioned ones.

[0039] The background / noise removal processor 40B is configured to selectively execute one or more image processing functions for the purpose of removing noise and objects other than overhead lines, such as buildings captured in the background. As the background / noise removal process, for example, GSTH (grayscale top hat) processing can be applied, which shrinks and expands a grayscale image to open it, and then subtracts the original image to be expanded and contracted. Note that the background / noise removal process included in the background / noise removal processor 40B is not limited to the above.

[0040] The binarization processing unit 40C is configured to selectively execute one or more image processing functions for converting an image of multiple gradations into two gradations, for example, black and white, and extracting only the worn area 9a. As the binarization process, for example, a discriminant analysis binarization process can be applied, which generates a histogram of brightness values ​​for the image and determines a binarization threshold according to the image so that the variance ratio of the intra-class variance and the inter-class variance for each of the background and the worn area 9a is maximized. Note that the binarization process included in the binarization processing unit 40C is not limited to the one described above.

[0041] The interpolation processing unit 40D is configured to selectively execute one or more image processing functions for the purpose of interpolating the shape of the wear area 9a by connecting together an area that is originally assumed to be a single wear area 9a when the area is divided into multiple areas after the binarization processing in the binarization processing unit 40C has been executed and an area that is assumed to be a wear area 9a has been extracted.

[0042] The interpolation process may be a closing process that expands or contracts an image in the horizontal direction X to join areas that are separated and close in the horizontal direction X, or a corrugation interpolation process that joins areas that are separated and shown in stripes or waves in the vertical direction Y. The interpolation process included in the interpolation processing unit 40D is not limited to the above.

[0043] 4 is a schematic diagram showing an example of a worn area extraction image temporarily acquired by the trolley wire inspection device according to the present embodiment, which is a worn area extraction image 50A processed by the interpolation processing unit 40D as described above. In the worn area extraction image 50A, as shown in FIG. 3, due to lighting, the state of the worn area 9a of the trolley wire 9, the shooting environment, etc., a luminance difference occurs in the worn area 9a, and dark areas 9c and 9d that are lower in luminance than other areas may be generated. That is, in the worn area extraction image 50A processed by the interpolation processing unit 40D, the dark areas 9c and 9d are not detected as the worn area 9a, so that the accurate worn area 9a cannot be detected.

[0044] As shown in Fig. 4, in the wear area extraction image 50A processed by the interpolation processing unit 40D, only the bright wear area 9a is extracted. Therefore, in this embodiment, the wear area extraction image 50A processed by the interpolation processing unit 40D is corrected so that the dark areas 9c and 9d are detected as the wear area 9a. The wear area correction unit 40E searches for the wear area by raster scanning outward from the position of the wear area extracted in the extraction process of the wear area 9a for each line in the vertical direction of the image, and determines the position where the brightness value is equal to or less than a preset brightness value as the boundary between the sliding surface and the non-sliding surface, i.e., the boundary of the wear area 9a.

[0045] Fig. 5 is a schematic diagram showing an example of a worn area extraction image finally acquired by the contact wire inspection device according to this embodiment. As a result of the above-mentioned correction, the dark areas 9c and 9d shown in Fig. 4 are detected as the worn area 9a, so that the worn area 9a is accurately detected as shown in Fig. 5. The worn area correction unit 40E transmits the corrected worn area extraction image 50B to the post-processing unit 41 together with the number of corresponding worn areas 9a, length information including the start and end coordinates of each worn area 9a in the vertical direction Y, and information on the image processing execution procedure (or processing pattern) M corresponding to the worn area extraction image.

[0046] In this way, the wear area extraction image generation unit 32 accurately extracts the wear area of ​​the trolley wire 9 by executing image processing functions using the line sensor image 50 as input in accordance with each of the multiple image processing execution procedures M using the image processing unit 40 and post-processing unit 41, and generates multiple wear area extraction images 50B corresponding to each of the multiple image processing execution procedures M.

[0047] Each image processing function included in the contrast adjustment processing unit 40A, the background / noise removal processing unit 40B, the binarization processing unit 40C, the interpolation processing unit 40D, and the wear area correction unit 40E is executed in accordance with a processing pattern (image processing execution procedure) M, which is the execution order for executing each image processing function, registered in the image processing execution procedure memory unit 33.

[0048] 6 is an explanatory diagram of the image processing execution procedure storage unit 33 of the trolley wire inspection device of the present embodiment. In FIG. 6, the image processing execution procedure storage unit 33 includes a processing storage unit 33a, a parameter set storage unit 33b, and a processing pattern registration unit 33c.

[0049] The processing storage unit 33a stores each of the image processing functions executed in each of the contrast adjustment processing unit 40A, the background / noise removal processing unit 40B, the binarization processing unit 40C, the interpolation processing unit 40D, and the wear area correction unit 40E, which have already been described. The processing storage unit 33a in Fig. 6 stores X image processing functions PR1 to PRX, from PR1 to PRX, which are included in any of the above-mentioned processing units 40A, 40B, 40C, 40D, and 40E.

[0050] Furthermore, the parameter set storage unit 33b stores parameter sets that can be used during actual execution of each of the image processing functions PR1-PRX stored in the process storage unit 33a. The parameter set storage unit 33b in Fig. 6 stores Y types of parameter sets, from PS1 to PSY, that are used in any one or more of the X image processing functions PR1-PRX stored in the process storage unit 33a.

[0051] The processing pattern registration unit 33c stores a plurality of processing patterns M for executing each of the above image processing functions when processing the line sensor image 50. In the processing pattern registration unit 33c of Fig. 6, L processing patterns M1 to ML are stored.

[0052] 6 focuses on the first processing pattern M1 of these L processing patterns M1 to ML. Processing pattern M1 is registered to execute Z image processing functions P1 to PZ in sequence. Here, image processing function P1 in processing pattern M1 refers to image processing function PR1 in processing storage unit 33a and parameter set PS2 in parameter set storage unit 33b. This indicates that image processing function P1 in processing pattern M1 is actually executed by applying parameter set PS2 to image processing function PR1 stored in processing storage unit 33a.

[0053] Furthermore, in the image processing function P2 that is executed second in the first processing pattern M1, only the image processing functions PRX stored in the processing storage unit 33a are referenced, and the parameter sets in the parameter set storage unit 33b are not referenced. In this way, when the image processing functions PR1 to PRX stored in the processing storage unit 33a are registered in the processing pattern M, the parameter sets in the parameter set storage unit 33b do not necessarily need to be associated with each other and referenced.

[0054] Although detailed description will be omitted, like the processing pattern M1, the processing patterns M2 to ML are configured by expressing image processing functions that are executed by referring to the processing storage unit 33a and the parameter set storage unit 33b.

[0055] In each of the processing patterns M1 to ML stored in the processing pattern registration unit 33c, the number of image processing functions to be executed is not fixed but variable, that is, the number of image processing functions to be executed in each of the processing patterns M1 to ML is basically different from one another.

[0056] In this way, the processing pattern M is configured by registering multiple image processing functions or combinations of image processing functions and parameter sets used in the image processing functions in an ordered manner. In this way, the processing pattern M can be said to be an image processing execution procedure M in which the execution order of each image processing function when processing the line sensor image 50 is registered together with a parameter set that indicates how each image processing function is actually executed. Hereinafter, the processing pattern M will be referred to as the image processing execution procedure M.

[0057] As described above, each image processing function is classified into processes for the purpose of contrast adjustment processing, background / noise removal processing, binarization processing, and interpolation processing. In each image processing execution procedure M, the image processing functions are registered so as to be executed in the order of the processing classification. For example, since it is basically meaningless to execute contrast adjustment after executing binarization processing, an image processing execution procedure M in which an image processing function included in the contrast adjustment processing section 40A is executed after executing an image processing function included in the binarization processing section 40C is basically not registered.

[0058] Furthermore, in order to extract the worn area 9a, at the very least, the binarization process must be performed. In other words, the image processing execution procedure M registers an order of image processing functions such that the image processing function included in the binarization processing unit 40C is executed at least once, and the image processing functions included in the other processing units 40A, 40B, 40D, and 40E are executed as necessary, i.e., 0 or more times. In this manner, each of the multiple image processing execution procedures M registers 0 or more contrast adjustment processes, 0 or more background / noise removal processes, 1 or more binarization processes, and 0 or more interpolation processes to be executed in this order.

[0059] Furthermore, the order of the image processing functions included in each of the processing units 40A, 40B, 40C, 40D, and 40E may be registered so that each of the image processing functions is executed multiple times. For example, the image processing execution procedure M may be constructed so that in the interpolation processing unit 40D, the closing process joins together areas divided in the horizontal direction X, and then the corrugation interpolation process joins together areas divided in the vertical direction Y.

[0060] Alternatively, the same image processing function may be registered in the image processing execution procedure M so that it is executed multiple times with the same parameter set or with different parameter sets, either consecutively or interspersed with the execution of other image processing functions within the same processing classification.

[0061] A plurality of image processing execution procedures M are registered so that all combinations of processing procedures can be realized between the image processing functions in each of the processing units 40A, 40B, 40C, 40D, and 40E. Each of the multiple image processing execution procedures M has different accuracy in extracting the worn area 9a and suitability for conditions such as the background of the line sensor image 50. For this reason, each of the multiple image processing execution procedures M is stored in association with a priority. For example, it is conceivable to set a high priority to the image processing execution procedure M that is not significantly affected by the brightness value of the background and can always achieve a certain level of extraction accuracy for the worn area 9a. In this way, the priority is set higher for a wear region 9a that is considered to have a higher extraction accuracy.

[0062] As described above, the image processing unit 40 executes each of the image processing execution procedures M, generates a processed image corresponding to each image processing execution procedure M, and transmits the processed image to the post-processing unit 41.

[0063] The post-processing unit 41 receives the processed image from the image processing unit 40, extracts the wear area 9a by performing edge extraction, and calculates the length of the wear area 9a in the vertical direction Y for each of the wear areas 9a if multiple wear areas 9a are extracted in the processed image. As already described, in this embodiment, a maximum of four trolley wires 9 may be provided overlapping each other. That is, a maximum of four trolley wires 9 may be captured in one line sensor image 50. For this reason, when five or more wear areas 9a are extracted, the post-processing unit 41 treats the four areas in descending order of length as wear areas 9a, and regards other areas shorter than these as not wear areas 9a. The post-processing unit 41 transmits the image after edge extraction as a wear area extraction image 50A to the wear area extraction image evaluation unit 34 together with the number of corresponding wear areas 9a, length information including the start point coordinates and end point coordinates of each wear area 9a in the vertical direction Y, and information on the image processing execution procedure M corresponding to the wear area extraction image.

[0064] The wear area extraction image evaluation unit 34 receives the corrected wear area extraction images 50B corresponding to each of the multiple image processing execution procedures M and each related information, calculates an evaluation value for each of the multiple received wear area extraction images 50B, and selects the wear area extraction image with the highest evaluation value. The wear area extraction image generating unit 32 associates each wear area extraction image with a determination of how many wear areas 9a are captured in the wear area extraction image, and transmits the determined result to the wear area extraction image evaluating unit 34. The wear area extraction image evaluating unit 34 compares the number of wear areas 9a in each wear area extraction image with the number of trolley wires 9 at the actual site where the wear area extraction image was captured, and calculates an evaluation value of the wear area extraction image.

[0065] The evaluation value of the worn area extraction image is determined by using the fact that the number of contact wires in the image is known from preregistered equipment information, and by performing cost calculations for each time series (line) of images, either a cost evaluation (the lower the cost, the higher the evaluation) is used, in which the worn area extraction image with the lowest cost processing pattern is adopted, or a likelihood evaluation (the higher the likelihood, the higher the evaluation) is used, which is an index indicating that the worn area 9a has image features similar to the contact wire 9, for each of the multiple worn area extraction images. Please refer to Patent No. 7196806 for details on cost evaluation and likelihood evaluation.

[0066] The wear area extraction image evaluation unit 34 calculates the center of gravity coordinates and wear surface width of each wear area 9a for the wear area extraction image with the highest evaluation value based on cost evaluation or likelihood evaluation, and transmits them to the trolley wire deviation calculation unit 35 and the trolley wire remaining diameter calculation unit 36 ​​together with the wear area extraction image with the highest evaluation value.

[0067] The trolley wire deviation calculation unit 35 receives the worn area extraction image selected as the one with the highest evaluation value, and calculates the deviation of the trolley wire 9 based on the received image. Fig. 7(a) is an explanatory diagram of the deviation calculation principle. The deviation D (unit: mm) is expressed by the following equation using the center of gravity coordinate d (unit: pixel) of the wear area 9a received from the wear area extraction image evaluation unit 34, and the pre-set parameters of the distance hs (mm) from the track 2 to the sensor surface 22c of the line sensor 22, the focal length f (mm) of the lens of the line sensor 22, the length s (mm) of the sensor surface 22c of the line sensor 22, the number of pixels p (pixels) of the line sensor 22, and the distance h (mm) from the track 2 to the trolley wire 9 calculated by a measuring device other than this trolley wire inspection device 20.

[0068]

number

[0069] The trolley wire deviation calculation unit 35 calculates the deviation of the trolley wire 9 as described above, and determines whether the trolley wire 9 is located within the allowable deviation range at the actual location corresponding to the worn area extraction image. If the contact wire 9 is not positioned within the allowable range of deflection, it is judged to be abnormal and recorded.

[0070] The trolley wire remaining diameter calculation unit 36 ​​receives the worn area extraction image selected as the one with the highest evaluation value, and calculates the remaining diameter of the trolley wire 9 based on the received image. Figure 7(b) is an explanatory diagram of the calculation principle of the remaining diameter. In this embodiment, the remaining diameter of the trolley wire 9, that is, the height of the trolley wire 9 after wear, is calculated as the remaining diameter. The trolley wire remaining diameter calculation unit 36, using the same principle as the trolley wire deviation calculation unit 35, calculates the actual wear surface width W (mm) of the trolley wire 9 based on the centroid coordinate d (pixels) and the wear surface width w (pixels) of the wear area 9a received from the wear area extraction image evaluation unit 34. The remaining diameter Dr (mm) of the trolley wire 9 is expressed by the following equation using the wear surface width W (mm) and the radius of the trolley wire 9.

[0071]

number

[0072] The trolley wire remaining diameter calculation unit 36 ​​calculates the remaining diameter of the trolley wire 9 as described above, and determines whether the remaining diameter is below the control value. If the remaining diameter is below the control value, it is judged to be abnormal and this is recorded.

[0073] Next, Fig. 8 is a flowchart for explaining the operation of the above-mentioned trolley wire inspection method by the trolley wire inspection device 20 according to this embodiment. When the process is started, the line sensor image generating unit 30 arranges, for example, 1000 lines in a vertical chronological order in the input image from the line sensor 22 to generate a line sensor image 50 as shown in Fig. 3 and transmits it to the wear area extraction image generating unit 32, and the environment determining unit 31 determines the environment in which the input image was captured based on the line sensor image 50 generated by the line sensor image generating unit 30 (step S10).

[0074] Next, in the wear area extraction image generation unit 32, the contrast adjustment processing unit 40A adjusts the gradation of the line sensor image 50 (step S12), the background / noise removal processing unit 40B removes noise and objects other than the overhead lines, such as buildings, captured in the background (step S14), and the binarization processing unit 40C converts the image with multiple gradations into two gradations, for example black and white, and extracts only the wear area 9a (step S16).

[0075] Next, the interpolation processing unit 40D targets the image in which the binarization processing unit 40C has performed binarization processing and the area assumed to be the wear area 9a has been extracted, and if the area assumed to be a single wear area 9a is divided into multiple areas, the interpolation processing unit 40D interpolates the shape of the wear area 9a by connecting these areas together (step S18).

[0076] Next, the wear area correction unit 40E uses a raster scan to search for the boundary between the sliding surface and the non-sliding surface outward from the position extracted in the extraction process of the wear area 9a for each line in the vertical direction of the image, and determines the position where the brightness value is below a preset brightness value to be the sliding surface boundary, thereby correcting the wear area extraction image 50A and detecting the accurate wear area 9a (step S20).

[0077] Next, the post-processing unit 41 generates, as the corrected wear area extraction image 50B, length information including the number of corresponding wear areas 9a and the start and end coordinates of each wear area 9a in the vertical direction Y, and transmits this to the wear area extraction image evaluation unit 34 together with information regarding the image processing execution procedure M corresponding to the wear area extraction image (step S22).

[0078] Next, the wear area extraction image evaluation unit 34 takes the image after edge extraction from the wear area extraction image generation unit 32 as a wear area extraction image and calculates an evaluation value (likelihood evaluation or cost evaluation) for each of the received multiple wear area extraction images based on the number of corresponding wear areas 9a, length information including the start point coordinates and end point coordinates in the vertical direction Y of each wear area 9a, and information on the image processing execution procedure M corresponding to the wear area extraction image (step S24). The generation and evaluation of the wear area extraction image are executed for all image processing execution procedures M stored in the image processing execution procedure storage unit 33.

[0079] Next, it is determined whether generation and evaluation of wear area extraction images have been performed for all image processing execution procedures M (step S26), and if there are any image processing execution procedures M that have not been executed (NO in step S26), transition is made to step S10 and processing for the unexecuted image processing execution procedures M is continued.

[0080] On the other hand, if there is no unexecuted image processing execution procedure M (YES in step S26), the wear area extraction image evaluation unit 34 judges the image with the highest evaluation value among all the wear area extraction images as the image in which the wear area 9a is most appropriately extracted (step S28). The wear area extraction image evaluation unit 34 calculates the center of gravity coordinates and wear surface width of each wear area 9a for the wear area extraction image with the highest evaluation value, and transmits them to the trolley wire deviation calculation unit 35 and the trolley wire remaining diameter calculation unit 36 ​​together with the wear area extraction image with the highest evaluation value.

[0081] Next, the trolley wire deflection calculation unit 35 receives the wear area extraction image selected as the one with the highest evaluation value, and calculates the deflection of the trolley wire 9 based on this (step S30). Also, the trolley wire remaining diameter calculation unit 36 ​​receives the wear area extraction image selected as the one with the highest evaluation value, and calculates the remaining diameter of the trolley wire 9 based on this (step S32). Then, the process ends.

[0082] According to the above-described embodiment, the trolley wire inspection device 20 includes a line sensor 22 for capturing an image of the trolley wire 9, and detects the trolley wire 9 based on an image captured by the line sensor 22 as an input image. The trolley wire inspection device 20 includes a line sensor image generating unit 30 that generates a line sensor image 50 by arranging the input images in time series, an image processing execution procedure storage unit 33 in which the execution order of a plurality of image processing functions is registered as a plurality of image processing execution procedures M when sequentially executing the plurality of image processing functions on the line sensor image 50, and an image processing execution procedure storage unit 33 in which the execution order of the plurality of image processing functions is registered as a plurality of image processing execution procedures M, and the trolley wire inspection device 20 detects the trolley wire 9 based on the image captured by the line sensor 22 as an input image. the wear area extraction image generating unit 32 extracts a wear area 9a of the trolley wire, scans outward from the extracted wear area of ​​the trolley wire and corrects the wear area by setting the position where the brightness value becomes equal to or lower than a preset brightness value as the boundary of the wear area, and generates a plurality of wear area extraction images corresponding to each of a plurality of image processing execution procedures M; a wear area extraction image evaluating unit 34 calculates an evaluation value of each of the plurality of wear area extraction images and selects the wear area extraction image with the highest evaluation value; a trolley wire deviation calculating unit 35 calculates the deviation of the trolley wire 9 based on the selected wear area extraction image; and a trolley wire remaining diameter calculating unit 36 ​​calculates the remaining diameter of the trolley wire 9.

[0083] In addition, the trolley wire inspection method in this embodiment is a trolley wire inspection method in which an image captured by a line sensor 22 that images the trolley wire 9 is used as an input image and the trolley wire 9 is inspected based on this, the input images are arranged in chronological order to generate a line sensor image 50, and when multiple image processing functions are sequentially executed on the line sensor image 50, the execution order is registered as multiple image processing execution procedures M, and the image processing functions are executed using the line sensor image 50 as an input according to each of the multiple image processing execution procedures M to extract a worn area 9a of the trolley wire 9, scan outward from the extracted worn area 9a and correct the worn area 9a by setting the position where the brightness value is below a predetermined brightness value as the boundary of the worn area 9a, generate multiple wear area extraction images corresponding to each of the multiple image processing execution procedures M, calculate an evaluation value for each of the multiple wear area extraction images and select the wear area extraction image with the highest evaluation value, and calculate both the remaining diameter and deviation of the trolley wire 9 based on the selected wear area extraction image.

[0084] According to the above-described configuration, even if a brightness difference occurs in the worn area 9a due to lighting, the condition of the worn area 9a of the trolley wire 9, the shooting environment, etc., the worn area 9a of the trolley wire 9 can be accurately detected, improving the accuracy of extraction of the worn area 9a of the trolley wire 9 and also improving the accuracy of calculation of the remaining diameter and deviation.

[0085] According to the present embodiment, a worn area extraction image is generated for each of the multiple image processing execution procedures M, an evaluation value is calculated for each of these worn area extraction images, the worn area extraction image with the highest evaluation value is selected, and both the remaining diameter and deviation of the trolley wire 9 are calculated based on this. That is, a number of worn area extraction images corresponding to the number of image processing execution procedures M are generated, and the worn area extraction image most suitable for evaluating the remaining diameter and deviation is selected from among them as the evaluation target for the remaining diameter and deviation. As a result, the processing result of the image processing execution procedure M suitable for processing the line sensor image 50 to be processed among the multiple registered image processing execution procedures M is selected as the worn area extraction image.

[0086] In this way, a wear area extraction image suitable for calculating the remaining diameter and deviation of the trolley wire 9 can be generated and the remaining diameter and deviation can be measured without the operator having to select a combination of image processing functions suitable for the line sensor image 50 to be processed through trial and error, thereby reducing the labor required for the operator to select image processing functions suitable for the input image.

[0087] Further, according to this embodiment, a priority is associated with each of the multiple image processing execution procedures M and stored, and when the same evaluation value is calculated for multiple wear area extraction images, the wear area extraction image evaluation unit 34 selects the wear area extraction image corresponding to the image processing execution procedure M with the highest priority as the wear area extraction image with the highest evaluation value. Therefore, when the same evaluation value is calculated for multiple wear area extraction images, the wear area extraction image corresponding to the image processing execution procedure M with the highest priority is selected as the wear area extraction image with the highest evaluation value. Therefore, even when there are multiple wear area extraction images having similar evaluation values, the wear area extraction image corresponding to the image processing execution procedure M with the highest priority is selected, so that it becomes easier to select a wear area extraction image suitable for evaluating the remaining diameter and deviation.

[0088] According to the present embodiment, the wear area extraction image evaluation unit 34 calculates the number of wear areas 9a for each of the multiple wear area extraction images, and calculates the evaluation value so that the evaluation value is higher when the difference between the number of wear areas 9a and the actual number of trolley wires 9 is small, so that a wear area extraction image in which the number of actual trolley wires 9 and the number of wear areas 9a match is more likely to be selected as a wear area extraction image for calculating the remaining diameter and deviation. This improves the extraction accuracy of the wear areas 9a of the trolley wires 9, and also improves the calculation accuracy of the remaining diameter and deviation.

[0089] According to the present embodiment, an appropriate image processing execution procedure is selected according to the environment, and a wear area extraction image corresponding to the selected procedure is generated, thereby improving the calculation accuracy of the remaining diameter and deviation, and shortening the processing time or reducing the processing load. Moreover, an image processing execution procedure M that does not correspond to the selected environment is not executed, so that the processing time and memory required for the execution of the trolley wire inspection device 20 can be reduced.

[0090] In addition, according to this embodiment, the wear area extraction image with the highest evaluation value, i.e., the highest trolley wire likelihood, is selected, so that a wear area extraction image whose image features of the wear area 9a are similar to the appearance of the actual trolley wire 9 is more likely to be selected as the wear area extraction image for calculating the remaining diameter and deviation, thereby improving the accuracy of extraction of the wear area 9a of the trolley wire 9 and also improving the accuracy of calculation of the remaining diameter and deviation.

[0091] In the above embodiment, for example, the post-processing unit 41 has been described as being included in the wear area extraction image generating unit 32 for convenience of explanation, but this is not limiting. The post-processing unit 41 may be included in the wear area extraction image evaluating unit 34, or may be configured as a function independent of each of the wear area extraction image generating unit 32 and the wear area extraction image evaluating unit 34. Needless to say, the configuration within the control device 23 may be changed without departing from the spirit of the present invention. In the above embodiment, the trolley wire inspection device includes both the trolley wire deflection calculation unit 35 and the trolley wire remaining diameter calculation unit 36, and is configured to calculate both the remaining diameter and deflection of the trolley wire 9, but is not limited to this. The trolley wire inspection device may be configured to calculate only either the remaining diameter or the deflection of the trolley wire, for example.

[0092] In addition, the present invention is not limited to the above-mentioned embodiments and each modified example described with reference to the drawings, and it is possible to select and discard the configurations described in the above embodiments and each modified example, or to change them to other configurations as appropriate, as long as it does not deviate from the gist of the present invention. [Explanation of symbols]

[0093] 1 Inspection vehicle 9 Contact Wire 9a Wear area 9c, 9d dark region 20 Contact Wire Inspection Device 21 Lighting 22 Line sensor 23 Control device 30 Line sensor image generation unit 31 Environmental Judgment Department 32 Wear area extraction image generation unit 33 Image processing execution procedure memory unit 34 Wear area extraction image evaluation unit 35 Contact wire deflection calculation unit (contact wire inspection unit) 36 Contact wire remaining diameter calculation section (contact wire inspection section) 40 Image processing section 40A Contrast adjustment processing unit 40B Background / noise removal processing section 40C Binarization processing section 40D Interpolation Processing Unit 40E Wear area correction part 41 Post-processing section 50 Line sensor images 50A, 50B Wear area extraction images M, M1, M2, M3 Image processing execution procedure

Claims

1. A trolley wire inspection device comprising a line sensor for capturing an image of a trolley wire, and inspecting the trolley wire based on an image captured by the line sensor as an input image, a line sensor image generating unit that generates a line sensor image by arranging the input images in time series; an image processing execution procedure storage unit in which execution orders of a plurality of image processing functions for sequentially executing the plurality of image processing functions on the line sensor image are registered as a plurality of image processing execution procedures; a wear area extraction image generating unit that extracts a wear area of ​​the trolley wire by executing the plurality of image processing functions using the line sensor image as an input in accordance with each of the plurality of image processing execution procedures, corrects the wear area by scanning outward from the extracted wear area of ​​the trolley wire and setting a position where a brightness value becomes equal to or less than a preset brightness value as a boundary of the wear area, and generates a plurality of wear area extraction images corresponding to each of the plurality of image processing execution procedures; a wear area extraction image evaluation unit that calculates an evaluation value for each of the plurality of wear area extraction images and selects the wear area extraction image with the highest evaluation value; a trolley wire inspection unit that calculates one or both of a remaining diameter and a deviation of the trolley wire based on the selected wear area extraction image with the highest evaluation value; A trolley wire inspection device comprising:

2. The trolley wire inspection device according to claim 1, characterized in that each of the plurality of image processing execution procedures is registered to be executed in the following order: zero or more contrast adjustment processes, zero or more background / noise removal processes, one or more binarization processes, and zero or more interpolation processes.

3. a priority is associated with each of the plurality of image processing execution procedures and stored; 3. The trolley wire inspection device according to claim 1, wherein when the same evaluation value is calculated for a plurality of the wear area extraction images, the wear area extraction image evaluation unit selects the wear area extraction image corresponding to the image processing execution procedure with the highest priority as the wear area extraction image with the highest evaluation value.

4. The trolley wire inspection device according to claim 3, characterized in that the wear area extraction image evaluation unit calculates the number of wear areas for each of the plurality of wear area extraction images, and calculates the evaluation value so that the evaluation value is high when the difference between the number of wear areas and the actual number of the trolley wires is small.

5. The trolley wire inspection device described in claim 3, characterized in that the wear area extraction image evaluation unit calculates a trolley wire likelihood, which is an index indicating that the wear area has image features similar to the trolley wire, for each of the multiple wear area extraction images, and calculates the evaluation value so that the evaluation value is high when the trolley wire likelihood is high.

6. the image processing execution procedure storage unit registers the image processing execution procedures corresponding to each of a plurality of different environments when the image is captured by the line sensor; an environment determination unit that determines the environment in which the input image was captured based on the line sensor image, 2. The trolley wire inspection device according to claim 1, wherein the worn area extraction image generating unit generates the worn area extraction image according to the image processing execution procedure corresponding to the determined environment.

7. A trolley wire inspection method, comprising: inspecting the trolley wire based on an input image captured by a line sensor that captures an image of the trolley wire, the method comprising: generating a line sensor image by arranging the input images in time series; a plurality of image processing functions are sequentially executed on the line sensor image, the execution order of the plurality of image processing functions being registered as a plurality of image processing execution procedures, and the wear area of ​​the contact wire is extracted by executing the plurality of image processing functions using the line sensor image as an input in accordance with each of the plurality of image processing execution procedures; scanning the extracted wear area of ​​the trolley wire outwardly and determining a position where the brightness value becomes equal to or lower than a preset brightness value as a boundary of the wear area to correct the wear area, thereby generating a plurality of wear area extraction images corresponding to each of the plurality of image processing execution procedures; calculating an evaluation value for each of the plurality of wear area extraction images and selecting the wear area extraction image with the highest evaluation value; A trolley wire inspection method comprising: calculating either or both of the remaining diameter and deviation of the trolley wire based on the selected worn area extraction image with the highest evaluation value.

Images