WO2010084920A1 - Pantograph height measuring device and calibration method therefor - Google Patents

Abstract

Provided is a pantograph height measuring device which enables easy calibration in the measurement of the height of a pantograph (10a).  Also provided is a calibration method thereof.  The pantograph height measuring device is provided with a line sensor (20) installed on the roof of a car (10), a processing computer (30) for analyzing an image captured by the line sensor (20), and a calibration member (40) detachably provided within the range including the range of fluctuation of the pantograph (10a) and configured by disposing black regions (40b) and white regions (40w) alternately along a vertical direction, wherein the processing computer (30) finds an approximate expression for calculating the height of an overhead wire, the approximate expression being an expression indicating the relationship between the positions of the black regions (40b) and the white regions (40w) obtained from an image of the calibration member (40), which is captured by the line sensor (20), in the image, and the actual heights of the black regions (40b) and the white regions (40w).

Description

Pantograph height measuring device and calibration method thereof

The present invention relates to a pantograph height measuring device that measures the height of a pantograph using image processing and a calibration method thereof.

In electric railway facilities, it is necessary to keep the fluctuation range of the overhead line within the specified value. One of the inspection items is the measurement of the overhead line height. Since the height of this overhead line is equivalent to the height of the pantograph, which is a current collector installed on the roof of the vehicle, conventionally, the method of obtaining the height of the overhead line by measuring the height of the pantograph Is known. For example, the following is mentioned as a method of measuring the height of such a pantograph.

(A) Laser sensor system This system is a system in which a pantograph is scanned with a laser using a mirror or the like, and the height of the pantograph is measured by the phase difference of reflected waves or the deformation of the shape of the reflected laser.
(B) Light cutting sensor method This method is a method of projecting striped light onto a pantograph, receiving the stripes that are uneven according to the shape of the pantograph, and measuring the height of the pantograph.
(C) Image processing method As shown in FIG. 14, this method uses a line sensor camera (hereinafter referred to as a line sensor) 20 installed on the roof of the vehicle 10 to photograph the pantograph 10 a and processes the captured image. This is a method of measuring the height of the pantograph 10a by performing processing such as model matching and pattern matching in the computer 30 (see, for example, Patent Documents 1 and 2).

Among the above methods, the image processing method extracts the pixel position on the image matching the model of the pantograph 10a prepared in advance from the image of the pantograph 10a taken by the line sensor 20, and the line sensor 20 The actual height of the pantograph 10a is calculated from the pixel position on the image based on the distance from the to the pantograph 10a, the focal length of the lens of the photographing instrument, and the like.

This image processing method uses a line sensor 20 as a photographing instrument to increase the spatial resolution and improve the accuracy. This method has an advantage that it can be mounted not only on a test vehicle manufactured exclusively for measurement but also on a commercial vehicle because the device is smaller than the laser sensor method and the light cutting method.

Further, when using the method of Patent Document 2, the line sensor 20 is installed so as to look upward obliquely as shown in FIG. At this time, due to the relationship between the displacement direction of the pantograph 10a and the elevation angle of the line sensor 20, the resolution when the pantograph 10a is low and the resolution when it is high are different. Specifically, as shown in FIG. 30, the resolution is higher at the lower position, and the resolution is lower at the higher position. The reason why the resolution is higher at the position where the pantograph 10a is lower is that the distance from the line sensor 20 is closer at the lower position.

JP 2006-250774 A JP 2008-104312 A

In the method using the line sensor 20, as shown by the broken line in FIG. 14, if the line sensor 20 is installed in front of the pantograph 10a, the resolution of the image is almost constant over the fluctuation range of the height of the overhead line. Although the height of the pantograph 10a can be measured with high precision, if the line sensor 20 is installed at the same height as the pantograph 10a, the line sensor 20 may come into contact with the overhead wire 5 and lead to a serious accident.

Therefore, the line sensor 20 is actually installed obliquely below the pantograph 10a as shown by the solid line in FIG. However, when the line sensor 20 is installed as shown by a solid line in FIG. 14, the optical axis of the line sensor 20 is not orthogonal to the displacement direction (vertical direction) of the pantograph 10a but intersects diagonally, and the pantograph 10a The resolution of the image photographed by the line sensor 20 differs depending on whether the position is low or high. Specifically, since the distance between the pantograph 10a and the line sensor 20 is closer when the pantograph 10a is at a lower position, the resolution is higher than when the position of the pantograph 10a is higher.

For example, in Patent Document 2, the relationship between the height of the pantograph 10a, the focal length of the camera lens of the line sensor 20, and the position (pixel position) of the pantograph 10a on the image photographed by the line sensor 20 and the actual height of the pantograph 10a. The calculation is performed using the expressed ratio.

That is, the actual height of the pantograph 10a is H, the position of the pantograph 10a on the image taken by the line sensor 20 is P, the pixel size is n, the distance from the line sensor 20 to the pantograph 10a is l, and the lens of the line sensor 20 If f is the focal length, each relationship is expressed by the following equation (1).
H: P × n = 1: f (1)

When this is expanded, the following equation (2) is obtained.
H = (l × P × n) / f (2)

The actual height of the pantograph 10a is obtained using this equation (2). However, in order to perform such a calculation, it is necessary to measure in advance the focal length f of the lens, the distance l from the line sensor 20 to the pantograph 10a, and there is a problem that workability is poor.

Further, if the line sensor 20 is installed at the position indicated by the broken line in FIG. 14, the distance l from the line sensor 20 to the pantograph 10a may be constant, but if the line sensor 20 is installed at the position indicated by the solid line in FIG. Since the value of the distance l varies depending on the position of the upper pixel, if the calculation is performed with the distance l constant, an error occurs in the calculation result. Therefore, when the line sensor 20 is installed obliquely below the pantograph 10a, it is necessary to perform height correction calculation using projective transformation or the like. In order to perform this calculation, the elevation angle of the line sensor 20 is required, and it is necessary to perform complicated calculations.

Therefore, an object of the present invention is to provide a pantograph height measuring apparatus and a calibration method thereof that can easily perform calibration in pantograph height measurement.

A pantograph height measuring device according to a first invention for solving the above-mentioned problems includes a line sensor installed on a roof of a vehicle, and an image processing means for analyzing an image photographed by the line sensor, In a pantograph height measuring device for measuring the pantograph height of a running vehicle, for calibration, the dark color region and the light color region are alternately arranged along the vertical direction in a range including the fluctuation range of the pantograph. A member is detachably provided, and the image processing means includes a position on the image of the dark color region and the light color region obtained from an image obtained by photographing the calibration member by the line sensor, the dark color region, and the dark color region. A relational expression with the actual height of the light-colored area is obtained, and the image of the pantograph taken by the line sensor using this relational expression Characterized in that it consists of a position to calculate the height of the actual pantograph.

A pantograph height measuring device according to a second invention for solving the above-mentioned problem is the pantograph height measuring device according to the first invention, wherein a plurality of second pantograph height measuring devices connected in the vertical direction to the calibration member. A photographing line correction member comprising one color region and a second color region disposed around the first color region is detachably provided, and displays an image photographed by the line sensor. The photographing line correction member includes a display unit, and the width of the first color region and the second color region displayed on the display unit changes depending on the position and inclination of the photographing line of the line sensor. The shape of the first color region is set.

A pantograph height measuring device according to a third aspect of the present invention for solving the above-mentioned problems is the pantograph height measuring device according to the second aspect of the invention, wherein the photographing line correcting member is located at the center in the horizontal direction. The upper and lower widths of the horizontal center of the first color area are formed wider than the upper and lower widths on both sides so that one color area is in contact with the adjacent first color area. It is characterized by.

A pantograph height measuring device according to a fourth aspect of the present invention for solving the above-mentioned problems is the pantograph height measuring device according to any one of the first to third aspects of the invention, wherein the image processing means is connected to the line sensor. An input image creation unit that creates an input image in which input image signals are arranged in time series, a binarization processing unit that creates a binarized image obtained by binarizing the input image, and the binary A color area position detecting unit for detecting positions of the dark color area and the light color area on the binarized image; a position of the dark color area and the light color area on the binarized image; and the dark color area and the light color. And a relational expression calculation unit that calculates the relational expression based on an actual position of the region.

A pantograph height measuring device according to a fifth aspect of the present invention for solving the above-mentioned problems is the pantograph height measuring device according to the first aspect of the invention, wherein the photographing line correcting member is a horizontal portion of the photographing line correcting member. A center line is provided at the center of the direction.

A calibration method for a pantograph height measuring device according to a sixth aspect of the present invention for solving the above-described problem is that the pantograph of the running vehicle is photographed by a line sensor installed on the roof of the vehicle, and the line sensor A method for calibrating a pantograph height measuring device for analyzing the image taken by the method and measuring the height of the pantograph, wherein a dark color region and a light color region are alternately arranged along the vertical direction on the surface thereof A first step of installing a calibration member in the vicinity of the pantograph; a second step of photographing the calibration member by the line sensor; and an image on the image photographed by the line sensor in the image processing means. And detecting the position of the dark color region and the light color region of the Characterized in that comprising a third step of calculating the relationship between the actual position of the color region and the position and the dark region and the light color region on the image of the light color region.

A calibration method for a pantograph height measuring device according to a seventh aspect of the present invention for solving the above problem is the calibration method for a pantograph height measuring device according to the sixth aspect of the invention, wherein the region having the same shape is vertically aligned. A plurality of first color regions connected to each other and a second color region arranged around the first color region are arranged in color, and the first color region and the second color region are An imaging line correction member arranged so that the widths of the first color area and the second color area displayed on the display means change according to the position and the inclination of the imaging line of the line sensor. The photographing line correction member displayed on the display means for photographing the photographing line correction member by the line sensor and displaying an image photographed by the line sensor. The Fixed shooting line while checking the image of the use members, remove the imaging line correcting member, and performs the first, second and third step.

A calibration method for a pantograph height measuring apparatus according to an eighth aspect of the invention for solving the above problem is a calibration method for a pantograph height measuring apparatus according to the seventh aspect of the invention, wherein the photographing line correction member is: The vertical width of the horizontal center of the first color area is compared with the vertical width of both sides so that the first color area touches the adjacent first color area at the horizontal center. It is characterized by being formed wide.

According to a ninth aspect of the present invention, there is provided a calibration method for a pantograph height measuring apparatus according to a ninth aspect, wherein the image is a calibration method for a pantograph height measuring apparatus according to any one of the sixth to eighth aspects. A processing unit creates an input image in which image signals input from the line sensor are arranged in time series, creates a binarized image obtained by binarizing the input image, and outputs the binarized image. Detecting the positions of the dark color region and the light color region on the binarized image, based on the positions of the dark color region and the light color region and the actual positions of the dark color region and the light color region on the binarized image; A relational expression is calculated.

According to a tenth aspect of the present invention, there is provided a calibration method for a pantograph height measuring apparatus according to the tenth aspect of the present invention. A center line is provided at the center of the direction, and the photographing line is corrected based on the center line.

According to the pantograph height measuring apparatus according to the first invention described above, the line sensor installed on the roof of the vehicle and the image processing means for analyzing the image photographed by the line sensor are provided. In the pantograph height measurement device that measures the height of the pantograph, a calibration member is provided that is detachably provided with a dark color region and a light color region alternately arranged along the vertical direction within the range including the fluctuation range of the pantograph. The image processing means obtains a relational expression between the position of the dark color region and the light color region on the image obtained from the image obtained by photographing the calibration member by the line sensor and the actual height of the dark color region and the light color region, It is configured to calculate the actual pantograph height from the position on the pantograph image taken by the line sensor using this relational expression. Therefore, by analyzing the image taken of the calibration member without considering the focal length of the camera lens of the line sensor, the distance from the line sensor to the pantograph, the resolution of the image, the elevation angle of the line sensor, etc. Regardless of the operator, it is possible to easily obtain the relational expression between the positions of the dark color region and the light color region on the image and the actual height of the dark color region and the light color region from the image obtained by photographing the calibration member, and the line sensor Even when shooting in a state of looking up diagonally upward, the accuracy of pantograph height measurement can be improved without complicated calculations.

According to the pantograph height measuring apparatus according to the second invention described above, the calibration member is provided with a plurality of first color regions connected in the vertical direction and a first color region disposed around the first color region. A photographing line correction member comprising two color regions is detachably provided, and further includes display means for displaying an image photographed by the line sensor, and the photographing line correction member is displayed on the display means. In addition to the effects of the first invention, the shape of the first color area is set so that the width of the first color area and the second color area changes depending on the position and inclination of the photographing line of the line sensor. The position and orientation of the photographing line of the line sensor can be easily and reliably corrected so as to be orthogonal to the pantograph, and therefore, the height of the pantograph can be measured with higher accuracy.

According to the pantograph height measuring apparatus according to the third aspect described above, the photographing line correction member is arranged so that the first color region is adjacent to the adjacent first color region at the center in the horizontal direction. Since the vertical width at the center of the first color area in the horizontal direction is formed wider than the vertical width on both sides, the first color area is displayed on the display means in order to make the photographing line orthogonal to the pantograph. It is only necessary to correct the position and inclination of the photographic line so that is continuously displayed, and it is possible to easily correct the position and inclination of the photographic line.

According to the pantograph height measuring device according to the fourth invention described above, the image processing means creates an input image in which the image signals input from the line sensor are arranged in time series, and the input image A binarization processing unit that creates a binarized image obtained by binarizing the color, a color region position detection unit that detects positions of dark and light color regions on the binarized image, and a binarized image Since it has a relational expression calculation unit that calculates a relational expression based on the positions of the upper dark color area and the light color area and the actual position of the dark color area and the light color area, the darkness obtained from an image obtained by photographing the calibration member A process of calculating a relational expression between the position of the color area and the light color area on the image and the actual height of the dark color area and the light color area can be smoothly performed.

According to the pantograph height measuring apparatus according to the fifth aspect described above, the photographing line correction member has a center line at the center in the horizontal direction of the photographing line correction member, so that the inclination of the photographing line is corrected. Nevertheless, it is possible to objectively determine whether the direction in which the line sensor is rotated is correct.
Further, it is possible to make corrections while viewing the image being photographed without being aware of the actual rotation or horizontal movement of the line sensor.
Moreover, it is more versatile and can be easily corrected without requiring human sense or experience.
Also, by increasing the accuracy of calibration, the height of the pantograph can be accurately measured.

According to the calibration method of the pantograph height measuring device according to the sixth aspect described above, a pantograph of a running vehicle is photographed by a line sensor installed on the roof of the vehicle, and an image photographed by the line sensor is analyzed. A calibration method of a pantograph height measuring device for measuring the height of a pantograph, wherein a calibration member in which a dark color region and a light color region are alternately arranged along a vertical direction on a surface of the pantograph is provided. A first step of installing in the vicinity, a second step of photographing the calibration member by the line sensor, and detecting positions of dark and light color regions on the image photographed by the line sensor in the image processing means. In addition, the position of the detected dark color region and light color region on the image and the dark color region and light color region Since it consists of a third step of calculating the relational expression with the actual position, it is not necessary to consider the focal length of the camera lens of the line sensor, the distance from the line sensor to the pantograph, the resolution of the image, the elevation angle of the line sensor, etc. In addition, by analyzing the image obtained by photographing the calibration member, the positions of the dark color region and the light color region on the image and the dark color region and the light color region obtained from the image obtained by photographing the calibration member without depending on the operator. The relational expression with the actual height can be easily calculated, and the accuracy of pantograph height measurement can be calculated without complicated calculations even when the line sensor is shooting obliquely looking up. Can be improved.

According to the calibration method of the pantograph height measuring apparatus according to the seventh aspect described above, the first color area formed by connecting a plurality of areas having the same shape in the vertical direction and the first color area are arranged around the first color area. The first color area and the second color area are displayed on the display means, and the width of the first color area and the second color area is taken by the line sensor. Display that displays the image taken by the line sensor by setting the photographing line correcting member arranged in a color so as to change according to the position and inclination of the line, photographing the photographing line correcting member by the line sensor The first, second, and third steps are performed after correcting the shooting line while removing the shooting line correcting member while checking the image of the shooting line correcting member displayed on the means. In addition to the effect, the position and orientation of the imaging line of the line sensor easily and reliably can be modified to be orthogonal to the pantograph, therefore, it is possible to perform the height measurement of the pantograph with higher accuracy.

According to the calibration method of the pantograph height measuring apparatus according to the eighth aspect described above, the photographing line correcting member is mutually connected to the first color area adjacent to the first color area at the center in the horizontal direction. Since the vertical width of the center in the horizontal direction of the first color region is wider than the vertical width on both sides of the first color area, the display means includes the display unit in order to make the shooting line orthogonal to the pantograph. It is only necessary to correct the position and inclination of the photographing line so that the first color region is displayed continuously, and the correction of the position and inclination of the photographing line can be easily performed.

According to the calibration method of the pantograph height measuring apparatus according to the ninth aspect described above, the image processing means creates an input image in which the image signals input from the line sensor are arranged in time series, and the input image is Create a binarized image by binarization processing, detect the position of dark and light color areas on the binarized image, and position and dark color of dark and light color areas on the binarized image Since the relational expression is calculated based on the actual position of the area and the light color area, the position of the dark color area and the light color area obtained from the image obtained by photographing the calibration member on the image, and the actual position of the dark color area and the light color area The process of calculating the relational expression with the height can be performed smoothly.

According to the calibration method of the pantograph height measuring apparatus according to the tenth aspect described above, a center line is provided at the center in the horizontal direction of the photographing line correction member, and the photographing line is corrected based on the center line. It is possible to objectively determine whether the direction in which the line sensor is rotated is correct in correcting the inclination of the photographing line.
Further, it is possible to make corrections while viewing the image being photographed without being aware of the actual rotation or horizontal movement of the line sensor.
Moreover, it is more versatile and can be easily corrected without requiring human sense or experience.
Also, by increasing the accuracy of calibration, the height of the pantograph can be accurately measured.

It is a schematic block diagram which shows the application example of the pantograph height measuring apparatus which concerns on Example 1 of this invention. It is explanatory drawing which shows an example of the member for calibration which concerns on Example 1 of this invention. It is a block diagram which shows schematic structure of the computer for processing concerning Example 1 of this invention. It is a flowchart which shows the process by the computer for a process in Example 1 of this invention. It is explanatory drawing which shows an example of the image for a calibration obtained in Example 1 of this invention. It is explanatory drawing which shows an example of the binarized image obtained in Example 1 of this invention. It is a graph which shows the relationship between the pixel position of the trolley line obtained in Example 1 of this invention, and actual height. FIG. 8A is a front view of a photographing line correction member according to Embodiment 2 of the present invention, and FIG. 8B is a side view of FIG. 8A. It is a flowchart which shows the process which concerns on correction of the imaging | photography line in Example 2 of this invention. FIGS. 10A, 10B, and 10C are explanatory diagrams illustrating examples of the position of the photographing line with respect to the photographing line correction member according to the second exemplary embodiment of the present invention. FIGS. 11A, 11B, and 11C are explanatory diagrams illustrating examples of calibration images obtained in FIGS. 10A, 10B, and 10C, respectively. 12A, 12 </ b> B, and 12 </ b> C are explanatory diagrams illustrating an example of the position of the photographing line with respect to the calibration member according to the first exemplary embodiment of the present invention. FIGS. 13A and 13B are explanatory views showing another example of the photographing line correcting member. It is explanatory drawing which shows the example of installation of a line sensor. It is a front view of the member for imaging line correction which concerns on Example 3 of this invention. It is the schematic diagram which showed the apparatus structure of the correction method using the member for imaging line correction which concerns on Example 3 of this invention. It is the block diagram which showed the structural example of the correction method using the member for imaging line correction which concerns on Example 3 of this invention. It is the flowchart which showed the correction method using the member for imaging line correction which concerns on Example 3 of this invention. It is the figure which showed the example of the picked-up image before performing the correction of the horizontal direction which concerns on Example 3 of this invention. It is the figure which showed the example of the picked-up image after performing the correction of the horizontal direction which concerns on Example 3 of this invention. It is the figure which showed the example of the picked-up image after correcting the rotation direction which concerns on Example 3 of this invention. It is the figure which showed the example of the picked-up image after completion | finish of the correction which concerns on Example 3 of this invention. It is the figure which showed the example of the imaging | photography line before performing the correction of the horizontal direction which concerns on Example 3 of this invention. It is the figure which showed the example of the imaging | photography line after performing the correction of the horizontal direction which concerns on Example 3 of this invention. It is the figure which showed the example of the imaging | photography line after performing the correction of the rotation direction which concerns on Example 3 of this invention. It is the figure which showed the example of the imaging | photography line after completion | finish of the correction which concerns on Example 3 of this invention. It is the figure which showed the example of the shape of the imaging | photography line correction member of the line sensor which concerns on Example 1, 2 of this invention. It is the figure which showed the example of the imaging | photography condition of the imaging line correction member which concerns on Example 1, 2 of this invention. It is the figure which showed the example of imaging | photography of the imaging line correction member which concerns on Example 1, 2 of this invention. It is the schematic diagram which showed the example of installation of the line sensor which concerns on patent document 2. FIG.

Hereinafter, an example of a pantograph height measuring apparatus according to the present invention will be described in detail with reference to the drawings.

A first embodiment of the pantograph height measuring apparatus according to the present invention will be described with reference to FIGS. FIG. 1 is a schematic configuration diagram of a pantograph height measuring apparatus according to the present embodiment, FIG. 2 is a front view of a calibration member according to the present embodiment, and FIG. 3 shows a structure of the pantograph height measuring apparatus according to the present embodiment. FIG. 4 is a flowchart showing the flow of calibration by the pantograph height measuring apparatus according to this embodiment, FIG. 5 is an explanatory diagram showing an example of a calibration image in this embodiment, and FIG. 6 is binarization. FIG. 7 is a graph showing the relationship between the actual height and the pixel position on the image.

As shown in FIG. 1, the pantograph height measuring apparatus according to the present embodiment includes a line sensor 20, a processing computer 30, and a calibration member 40.

The line sensor 20 is installed on the roof of the vehicle 10 so as to photograph the pantograph 10a. That is, the direction of the line sensor 20 is set so that the optical axis thereof is obliquely upward and the scanning line direction is orthogonal to the pantograph 10a. The image signal acquired by the line sensor 20 is input to the processing computer 30.

The processing computer 30 has a function of calculating an approximate expression for calculating the overhead line, which is a relational expression between the position of the calibration member 40 on the image photographed by the line sensor 20 and the actual position of the calibration member 40. As shown in FIG. 3, an input image creation unit 31, a binarization processing unit 32, a pixel width extraction unit 33 as a color region position detection unit, an approximate expression calculation unit 34 as a relational expression calculation unit, and a memory 35A and 35B are provided. The processing computer 30 is connected to a monitor 60 configured to display a calibration image (line sensor image) 1 and a binarized image 2 described later.

In the configuration for calculating the approximate expression for calculating the overhead line height, the input image creation unit 31 arranges image signals obtained by photographing the calibration member 40 input from the line sensor 20 in time series. A calibration image 1 (see FIG. 5) is created. The calibration image 1 is sent to the binarization processing unit 32 via the memories 35A and 35B.

The binarization processing unit 32 performs binarization processing on the calibration image 1 input from the input image creation unit 31 to create a binarized image 2 (see FIG. 6). The binarized image 2 created in the binarization processing unit 32 is sent to the pixel width extraction unit 33 via the memory 35B.

The pixel width extraction unit 33 extracts a trajectory 2b of a black region 40b and a trajectory 2w of a white region 40w, which will be described later, from the binarized image 2 input from the binarization processing unit 32, respectively. The width of each region 2b, 2w is obtained as the pixel width. The pixel width information extracted by the pixel width extraction unit 33 is sent to the approximate expression calculation unit 34 via the memory 35B.

The approximate expression calculation unit 34 calculates an approximate expression for calculating the overhead line height by the least square method based on the pixel width input from the pixel width extraction unit 33 and the actual widths of the black region 40b and the white region 40w measured in advance. Ask. The approximate expression for overhead line calculation calculated in the approximate expression calculation unit 34 is stored in the memory 35B.

Here, the least square method means that when a set of numerical values obtained by measurement is approximated using a specific function such as a linear function or logarithmic curve assumed from an appropriate model, the assumed function is This is a method of determining a coefficient that minimizes the sum of squares of the residuals so that a good approximation can be obtained.

With this configuration, the processing computer 30 can calculate the overhead line height calculation approximate expression by analyzing the image signal input from the line sensor 20.

The calibration member 40 is made of, for example, a plate-like member formed in a rectangular shape. The length of the calibration member 40 in the longitudinal direction is longer than the range of fluctuation of the pantograph, in other words, the range of fluctuation of the overhead wire. The position of the calibration member 40 close to the end surface of the pantograph 10a on the line sensor 20 side, specifically, the height of the calibration member 40 obtained by the processing computer 30 and the height of the pantograph 10a does not cause an error. Removably attached to the position of. Furthermore, the calibration member 40 is installed at a height that includes the range of the fluctuation range of the overhead wire.

As shown in FIG. 2, the calibration member 40 has black areas 40b and white areas 40w alternately arranged along the longitudinal direction on the surface thereof. In this embodiment, the black region 40b and the white region 40w have the same width (L), and the boundary lines thereof are orthogonal to the longitudinal direction of the calibration member 40, respectively.

Referring to FIG. 4, a process for calculating an approximate expression for overhead line height calculation using the pantograph height measuring apparatus according to this embodiment will be described.

When the calibration member 40 is installed in the vicinity of the pantograph 10a and imaging of the calibration member 40 by the line sensor 20 is started, the calibration input from the line sensor 20 is performed in the processing computer 30 as shown in FIG. The images of the calibration members 40 are arranged in time series to create a calibration image 1 as shown in FIG. 5 (step PA1). As shown in FIG. 5, the calibration image 1 displays a locus 1b of the black area 40b and a locus 1w of the white area 40w.

Here, in the calibration image 1, since the optical axis of the line sensor 20 is directed obliquely upward, the area below the calibration member 40 in which the distance from the line sensor 20 to the calibration member 40 is short. The width WH of the region above the calibration member 40 where the distance from the line sensor 20 to the calibration member 40 is long with respect to the width WL is displayed narrowly.

Subsequent to step PA1, binarization processing is performed on the calibration image 1 to create a binarized image 2 as shown in FIG. 6 (step PA2). As shown in FIG. 6, the binarized image 2 is substantially the same image as the calibration image 1.

Subsequent to step PA2, the locus 2b corresponding to the black region 40b and the locus 2w corresponding to the white region 40w of the calibration member 40 are extracted from the binarized image 2, and their widths (in this embodiment, this example). The distances p1 to p6) from one boundary line of the locus 2b and the locus 2w shown in FIG. 6 to the other boundary line are obtained (step PA3).

Subsequently, as shown in FIG. 7, the actual positions of the black region 40b and the white region 40w of the calibration member 40 (in this embodiment, from one boundary line between the black region 40b and the white region 40w to another boundary line). The relationship between the distances L to 6L) and the widths p1 to p6 obtained in step PA3 is acquired, and based on this, the height of the pantograph 10a, in other words, the height of the overhead line is calculated from the image taken by the line sensor 20. Thus, an approximate expression for calculating the overhead line, which is a relational expression for determining, is obtained by the method of least squares (step PA4). The approximate expression for overhead line calculation can be obtained by the above processing.

When measuring the height of the pantograph 10a using this approximate expression for calculating the overhead line height, first, as in Patent Document 2, the pixel position of the pantograph 10a in the captured image is obtained by image processing such as pattern matching. . Then, by substituting the obtained pixel position into the approximate expression obtained in step PA4, the height of the pantograph 10a can be obtained with high accuracy even when the optical axis of the line sensor 20 is inclined. In addition, when calculating | requiring the height of an actual overhead wire, it is necessary to add the height etc. from the ground to the member 40 for calibration as an offset.

According to the pantograph height measuring apparatus according to the present embodiment configured as described above, the calibration can be performed without considering the focal length of the camera lens of the line sensor, the distance from the line sensor to the pantograph, the resolution of the image, and the like. Since an approximate expression for underline height calculation can be obtained by analyzing an image obtained by photographing the member 40, calibration can be easily performed regardless of the operator.

Thereby, even when the image is taken with the optical axis of the line sensor 20 facing obliquely upward, the pantograph can be obtained without performing complicated calculations taking into account the distance from the line sensor 20 to the pantograph 10a, the camera elevation angle, and the like. Measurement of the height of 10a can be performed with high accuracy.

A second embodiment of the pantograph height measuring apparatus according to the present invention will be described with reference to FIGS. 8A is a front view of the photographing line correction member used in the present embodiment, FIG. 8B is a side view of the photographing line correction member shown in FIG. 8A, and FIG. 9 is the present embodiment. FIG. 10A to FIG. 10C are explanatory diagrams showing examples of the position of the photographing line with respect to the photographing line correcting member, and FIGS. 11A to 11C are flowcharts showing the flow of processing for correcting the position of the line sensor. FIG. 12 is an explanatory diagram illustrating an example of a calibration image corresponding to FIG. 11, FIG. 12 is an explanatory diagram illustrating an example of the position of a photographing line with respect to a calibration member in the first embodiment of the present invention, and FIGS. FIG. 6 is a front view showing another example of a photographing line correction member.

The present embodiment is an example in which the photographing line of the line sensor is corrected using the photographing line correction member 50 shown in FIG. 8 before performing the calibration operation described in the first embodiment. The other configuration is substantially the same as the configuration of the first embodiment shown in FIGS. 1 to 7 described above. The same members are denoted by the same reference numerals, and redundant description is omitted, and different points are mainly described. .

In the first embodiment, as shown in FIG. 12A, the imaging line S of the line sensor 20 is orthogonal to the pantograph 10a, in other words, the line sensor 20 moves the calibration member 40 along its longitudinal direction. Set up to shoot. Thus, if the line sensor 20 is installed, the most ideal and more accurate calibration can be performed.

On the other hand, as shown in FIG. 12B, when the line sensor 20 is installed so that the photographing line S crosses both ends in the width direction of the calibration member 40, the calibration that appears on the calibration image 1 is displayed. Since the pixel width of the locus corresponding to the portion indicated by the broken-line circle in FIG. 12B of the working member 40 is shortened, there is a possibility that an accurate approximation formula for overhead line height cannot be obtained.

In addition, as shown in FIG. 12C, even when the shooting line S does not cross both ends of the calibration member 40 in the width direction, the shooting line S is in the longitudinal direction of the calibration member 40. When the angle θ is inclined, the width Wpc of the white area 40w on the imaging line S shown in FIG. 12C is (1 / cos θ) times the width Wpa of the white area 40w on the imaging line S shown in FIG. become. Accordingly, the resolution corresponding to the photographing line S shown in FIG. 12C is (L / P) cos θ, which is cos θ times the resolution L / P corresponding to the photographing line S shown in FIG.

Here, for example, even if θ is inclined by 1 ° or 2 °, the value of cos θ is almost 1, so that sufficient accuracy can be ensured. However, since the line sensor 20 captures a one-dimensional image with the image pickup elements arranged in a line, the line sensor 20 captures the position of the calibration member 40 from the image displayed on the monitor 60 for calibration. It is difficult to grasp how much the member 40 is inclined with respect to the longitudinal direction. Therefore, in order to make the photographing line S of the line sensor 20 parallel to the longitudinal direction of the calibration member 40, the work may be complicated.

Therefore, in this embodiment, the photographing line correction member 50 shown in FIG. 8 is used to correct the inclination of the photographing line of the line sensor 20.

That is, in the present embodiment, as shown in FIG. 8, the photographing member correction member 50 is detachably attached to the surface of the calibration member 40 on the line sensor 20 side. The photographing line correcting member 50 is formed of a rectangular plate-shaped member, and a plurality of (four in FIG. 8) first black regions 50a as a first color region are arranged on a straight line along the vertical direction. On the other hand, a white region 50b as a second color region is arranged around the black region 50a. The black region 50a has a rhombus shape, and the opposite points of the adjacent photographing line correction member 50 are in contact with each other.

Based on FIG. 9, the flow of correcting the photographing line of the line sensor 20 by the pantograph height measuring apparatus according to the present embodiment will be described. As shown in FIG. 9, when correcting the position of the photographing line of the line sensor 20 in the present embodiment, first, the direction in which the black regions 50a are connected and the center o in the width direction of the calibration member 40 match. As described above, the photographing line correction member 50 is attached to the calibration member 40 (step PB1).

Subsequently, the photographing line correction member 50 is photographed by the line sensor 20 and displayed on the monitor 60 (step PB2). At this time, one of the images shown in FIGS. 11A to 11C is displayed on the monitor 60 in general. As shown in FIGS. 11 (a) and 11 (b), when black and white areas are alternately shown in a strip shape in the image, the shooting line S of the line sensor 20 is oblique or from the center o. It's off. On the other hand, as shown in FIG. 11C, when the same color is continuously displayed, the shooting line S coincides with the center o of the shooting line correction member 50.

Subsequently, the position of the photographing line is corrected (step PB3). That is, when the shooting line S of the line sensor 20 is shooting the position shown in FIG. 10A, an image as shown in FIG. 11A on the monitor 60, that is, the width of the black area 50a and the white area 50b. Images with the same width are displayed. In such a case, since the shooting line of the line sensor 20 is shifted in parallel from the center o, the shooting line S is moved by moving the direction of the line sensor 20 in the horizontal direction while checking the image displayed on the monitor 60. It can be corrected. The direction in which the direction of the line sensor 20 is moved may be moved in the direction in which the width of the black region 50a displayed on the monitor 60 is increased.

Further, when the shooting line S of the line sensor 20 is shooting the position shown in FIG. 10B, an image as shown in FIG. 11B on the monitor 60, that is, both the black area 50a and the white area 50b, respectively. Images with different widths are displayed. In such a case, since the shooting line S of the line sensor 20 is inclined with respect to the center o, first, the width of the black region 50a and the width of the white region 50b are respectively confirmed while checking the image displayed on the monitor 60. The imaging line of the line sensor 20 is rotated so that the width is substantially the same, and the imaging line S of the line sensor 20 is moved so as to be parallel to the center o, and then the line sensor 20 is moved in the horizontal direction. .

In this way, by correcting the shooting line S so that the black area 50a (or white area) is continuously displayed as shown in FIG. 11C, the position and orientation of the shooting line S are changed to the shooting line. The correction is made so as to coincide with the center o of the correction member 50.

When the photographing line S of the line sensor 20 is corrected, the photographing line correcting member 50 is removed from the calibration member 40 (step PB4), and the calibration process described in the first embodiment is performed (step PB5).

With this configuration, according to the pantograph height measuring apparatus according to the present embodiment, the operation of matching the imaging line of the line sensor 20 with the center o of the calibration member 40 can be easily performed regardless of the operator. It can be carried out.

Since the calibration can be performed in a state where the photographing line S of the line sensor 20 coincides with the center o of the calibration member 40, the height of the pantograph 10a can be measured with higher accuracy. .

In the above-described embodiment, an example in which the black region 50b of the photographing line correction member 50 is in the shape of a rhombus and the white region 50w is used as a background is illustrated. However, like the photographing line correction member 51 illustrated in FIG. The black region 51b may be a background, and the white region 51w may be a rhombus shape. The shape of the first color region is not limited to the rhombus shape, and the first color region 51b shown in FIG. It is sufficient that the vertical width of the center in the horizontal direction is wider than the vertical widths on both sides, such that one color area 52b has an elliptical shape and the periphery thereof is a second color area 52w. Needless to say, various modifications can be made without departing from the spirit of the present invention.

As described above, when using the method of Patent Document 2, the line sensor 20 is installed so as to look up obliquely upward as shown in FIG. At this time, due to the relationship between the displacement direction of the pantograph 10a and the elevation angle of the line sensor 20, the resolution when the pantograph 10a is low and the resolution when it is high are different. Specifically, as shown in FIG. 30, the resolution is higher at the lower position, and the resolution is lower at the higher position. The reason why the resolution is higher at the position where the pantograph 10a is lower is that the distance from the line sensor 20 is closer at the lower position.

In order to solve the difference in resolution as described above, a calibration method as in Examples 1 and 2 was proposed. According to the first and second embodiments, calibration can be automatically performed by photographing the calibration member 40 with the line sensor 20 and performing image processing.

However, in the first and second embodiments, it is necessary to correct the photographing line of the line sensor 20 at the time of calibration. In order to correct the photographing line of the line sensor 20, a photographing line correcting member 50 as shown in FIG. 27 is used. This is because, as indicated by 50L in FIG. 27 (a), the vertices of the rectangle are aligned on a straight line, so if the shooting line of the line sensor 20 matches this straight line, the image is shot in the shot image. The line correcting member 50 is blackened. Correction is performed while looking at the black and white width of the image so that the shooting line correction member 50 in the captured image is black. In addition, as shown in FIGS. 27B and 27C, black and white may be reversed, or a circle instead of a rectangle may be used.

When correction is performed using the shooting line correction member 50 in FIG. 27A, if the image is taken obliquely as indicated by S in FIG. 28A, the white width as shown in FIG. 29A is obtained. Displayed unevenly. In order to make the line sensor imaging line parallel to the center line 50Lc of FIG. 27A, the line sensor 20 is rotated to the left or right so that the white widths are equally spaced as shown in FIG. .

Actually, since the upper side is looked up diagonally, it is not evenly spaced, and the white width decreases toward the right (the white width increases toward the right depending on the shooting line). Correct the tilt. In this state, the line sensor 20 is moved in the horizontal direction and the line sensor 20 is corrected in the direction in which the black width increases. Finally, as shown in FIG. 29 (c), when the photographing line correction member 50 is all black in the photographed image, the photographing line correction is completed.

Although the shooting line can be corrected by the above method, the following method can be used to correct the shooting line more efficiently.
(1) A method of objectively determining whether the rotated direction is correct in correcting the inclination of the photographing line.
(2) A method in which correction is performed while viewing an image being shot without being aware of the actual rotation or horizontal movement of the line sensor 20.
(3) A more general correction method that does not require human sense or experience.

From the above, in the pantograph height measuring apparatus and its calibration method according to the present embodiment, in the correction of the photographing line at the time of calibration performed when the height of the pantograph 10a is measured using the line sensor 20, In addition to the methods of the first and second embodiments, there is no need for human sense and experience, and a configuration that allows more efficient correction while viewing the captured image is adopted.

Hereinafter, the configuration of the pantograph height measuring apparatus according to the present embodiment will be described.
FIG. 15 is a front view of the photographing line correcting member according to the present embodiment.
As shown in FIG. 15A, in the photographing line correcting member 100 in the pantograph height measuring apparatus according to the present embodiment, the center line 101 of the white line is in the target photographing line portion.

Note that the photographing line correcting member 100 is not limited to the shape as shown in FIG. 15A, and FIG. 15B in which black and white are reversed, and FIG. ). The white portion of the photographing line correction member 100 is a material that easily reflects light, and the black portion is a material that hardly reflects light.

FIG. 16 is a schematic diagram illustrating an apparatus configuration of a correction method using the photographing line correction member according to the present embodiment.
As shown in FIG. 16, the photographing line correction member 100 is attached to the pantograph 102. In FIG. 16, the side surface of the photographing line correction member 100 is shown. Further, in order to correct the position and inclination of the line sensor 103, the line sensor 103 is installed on the gonio stage 104 that can rotate in the horizontal direction. Note that the goniometer stage 104 may not be used as long as the structure can rotate without changing the center of rotation.

In order to photograph the photographing line correction member 100, the line sensor 103 installed on the gonio stage 104 is installed on the roof of the vehicle 105. In addition, an illumination 106 is installed in the vicinity of the line sensor 103 so that a black and white pattern of the photographing line correction member 100 can be photographed even in an environment with low illuminance such as at night, in a tunnel, or in a vehicle base. Further, a processing computer 107 is installed in the vehicle 105 in order to store an image photographed by the line sensor 103.

FIG. 17 is a block diagram illustrating a configuration example of a correction method using the photographing line correction member according to the present embodiment.
As shown in FIG. 17, in the correction method using the imaging line correction member 100 according to the present embodiment, the “line sensor 103” in which the imaging line correction member 100 is imaged and the operator 108 corrects the imaging line. In order to easily correct the imaging line of the line sensor 103 and the “processing computer 107” necessary for correcting the imaging line while the captured image is stored and displayed and the operator 108 confirms the image. In addition, a “photographing line correcting member 100” that can be removed is provided.
The above is the configuration of the pantograph height measuring apparatus according to the present embodiment.

Hereinafter, a calibration method in the pantograph height measuring apparatus according to the present embodiment will be described.
FIG. 18 is a flowchart showing a correction method using the photographing line correction member according to the present embodiment. Here, the photographing line correction member 100 to be used is shown in FIG.

As shown in FIG. 18, the photographing line correction member 100 is attached to the pantograph 102 in Step P100. At this time, the center line 101 of the photographing line correcting member 100 is made to coincide with the line to be photographed.
Next, in step P <b> 101, the photographing line correction member 100 is photographed by the line sensor 103.

Next, in step P102, the line sensor 103 is moved in the horizontal direction while confirming the captured image. At this time, the black portion of the photographing line correction member 100 on the image is moved in the direction of increasing, so that the center line 101 of the photographing line correction member 100 can be photographed on the image as shown in FIG. 19 to 22, Io represents the center of the image, Ia represents the photographing line correction member 100 on the image, and Ic represents the center line 101 of the photographing line correction member 100 on the image.

Next, in step P103, as shown in FIG. 19, the center line 101 of the photographing line correction member 100 on the image indicated by Ic is the image center indicated by Io on the photographing line correction member 100 on the image indicated by Ia. 20, the center line 101 of the photographing line correction member 100 indicated by Ic is close to the center of the image indicated by Io on the photographing line correction member 100 indicated by Ia as shown in FIG. The horizontal direction line sensor 103 is moved until it becomes.

Next, in step P104, the line sensor 103 is rotated. At this time, as shown in FIG. 21, the center line 101 of the photographing line correcting member 100 moves to a position away from the image center indicated by Io in the photographing line correcting member 100 portion on the image indicated by Ia. Then, the line sensor 103 is rotated.

Then, in Step P105, as shown in FIG. 22, Steps P102 to P104 are repeated until the portion of the photographing line correction member 100 on the image indicated by Ia is all white, and the photographing line becomes the photographing line correction member. When the center line 101 matches 100, the series of processing ends.
The above is the calibration method in the pantograph height measuring apparatus according to the present embodiment according to the present embodiment.

Here, the principle of the photographing line correction method according to the present embodiment will be described.
FIG. 23 is a diagram illustrating an example of a shooting line before correction in the horizontal direction.
The image photographed at this time is shown in FIG. 19, and the center line 101 of the photographing line correction member 100 indicated by Ic is captured at a position distant from the image center indicated by Io. In FIG. 23, S indicates the photographing line of the line sensor 103, and Sc indicates the center of the photographing line of the line sensor 103.

Next, the horizontal direction of the photographing line is corrected.
FIG. 24 is a diagram illustrating an example of the photographing line after the horizontal correction.
At this time, as shown in FIG. 20, the fact that the center line 101 of the photographing line correcting member 100 indicated by Ic approaches the image center indicated by Io indicates that the line sensor 103 indicated by Sc as indicated by M in FIG. This means that the center of the shooting line approaches the center line 101 of the shooting line correction member 100. In FIG. 24, S represents the photographing line of the line sensor 103, Sc represents the center of the photographing line of the line sensor 103, S 'represents the photographing line of the line sensor 103 before correction in the horizontal direction, and M represents the photographing line. Shows the horizontal correction.

Finally, if the center of the photographing line of the line sensor 103 indicated by Sc does not coincide with the extension of the center line 101 of the photographing line correcting member 100, the photographing line of the line sensor 103 indicated by S is for correcting the photographing line. It does not coincide with the center line 101 of the member 100. Since the final purpose is to match the photographing line of the line sensor 103 indicated by S with the center line 101 of the photographing line correction member 100, the center of the photographing line of the line sensor 103 indicated by S is used for correcting the photographing line. It is necessary to approach the center line 101 of the member 100.

That is, it is necessary to bring the center line 101 of the photographing line correction member 100 on the image indicated by Ic closer to the image center indicated by Io on the image.
At the end of step P103, the center of the photographing line of the line sensor 103 indicated by Sc has approached the center line 101 of the photographing line correction member 100.

Next, the rotation direction of the photographing line is corrected.
FIG. 25 is a diagram illustrating an example of the photographing line after the rotation direction is corrected.
At this time, as shown in FIG. 21, the fact that the center line 101 of the photographing line correcting member 100 on the image indicated by Ic is further away from the image center indicated by Io on the image is indicated by R in FIG. As shown, it means that the line sensor 103 has rotated. In FIG. 25, S represents the photographing line of the line sensor 103, Sc represents the center of the photographing line of the line sensor 103, S ″ represents the photographing line of the line sensor 103 before correction of the rotation direction, and R represents the photographing line. Shows the correction of the direction of rotation.

In order for the imaging line of the line sensor 103 indicated by S to coincide with the center line 101 of the imaging line correction member 100, the imaging line of the line sensor 103 indicated by S is parallel to the center line 101 of the imaging line correction member 100. Need to be.

Therefore, it is necessary to rotate the imaging line of the line sensor 103 indicated by S in a direction parallel to the center line 101 of the imaging line correction member 100. For that purpose, it is necessary to rotate in the direction shown in FIG. That is, as shown in FIG. 21, the center line 101 of the photographing line correction member 100 indicated by Ic on the image needs to be separated from the image center indicated by Io.
At the end of step P104, the photographing line of the line sensor 103 is rotated in a direction parallel to the center line 101 of the photographing line correction member 100.

It should be noted that when the line sensor 103 is rotated in step P104, it is necessary to rotate without changing the position of the center of the imaging line of the line sensor 103 indicated by Sc. Therefore, it is necessary to use an apparatus such as the gonio stage 104 that does not move the center of rotation. If the rotation center does not move, a device other than the gonio stage 104 may be used.

FIG. 26 is a diagram showing an example of the photographing line after the correction is completed.
By repeating step P102 to step P104, as shown in FIG. 26, the shooting line of the line sensor 103 shown in S coincides with the center line 101 of the shooting line correction member 100, and an image as shown in FIG. 22 is obtained. be able to. In FIG. 26, S indicates the shooting line of the line sensor 103, and Sc indicates the center of the shooting line of the line sensor 103.
Further, as shown in FIG. 19, even if the photographing line correction member 100 on the image indicated by Ia on the image is not on the right side but on the left side of the image center indicated by Io, the principle of the correction method does not change.

As described above, according to the pantograph height measuring apparatus and the calibration method thereof according to the present embodiment, whether or not the direction in which the line sensor 103 is rotated is objectively corrected to correct the inclination of the photographing line. Judgment can be made.
Further, it is possible to make corrections while viewing the image being shot without being aware of the actual rotation or horizontal movement of the line sensor 103.
Moreover, it is more versatile and can be easily corrected without requiring human sense or experience.
Further, by increasing the calibration accuracy, the height of the pantograph 102 can be measured with high accuracy.

The present invention is suitable for application to a pantograph height measuring apparatus and its calibration method.

1, 3A, 3B, 3C Calibration image 2 Binary image 10 Vehicle 20 Line sensor 30 Processing computer 31 Input image creation unit 32 Binary processing unit 33 Pixel width extraction unit 34 Approximation formula calculation unit 35A, 35B Memory 40 Calibration member 40b Black area 40w White area 50 Imaging line correction member 50b Black area 50w White area 60 Monitor S Imaging line 100 Imaging line correction member 101 Center line 102 Pantograph 103 Line sensor 104 Goniometer stage 105 Vehicle 106 Illumination 107 Processing computer 108 Worker

Claims (10)

1. In a pantograph height measuring device that includes a line sensor installed on a roof of a vehicle, and an image processing unit that analyzes an image captured by the line sensor, and that measures the height of a pantograph of a running vehicle,
   In a range including the fluctuation range of the pantograph, a calibration member formed by alternately arranging a dark color region and a light color region along the vertical direction is detachably provided,
   The image processing means includes a position on the image of the dark color region and the light color region obtained from an image obtained by photographing the calibration member by the line sensor and an actual height of the dark color region and the light color region. A pantograph height measuring apparatus configured to obtain a relational expression and calculate an actual pantograph height from a position on the image of the pantograph photographed by the line sensor using the relational expression.
2. An imaging line correction member comprising a plurality of first color regions connected in the vertical direction and a second color region arranged around the first color region is detachable from the calibration member. And provided
   Comprising display means for displaying an image taken by the line sensor;
   The photographing line correction member is configured such that the widths of the first color region and the second color region displayed on the display unit change according to the position and inclination of the photographing line of the line sensor. 2. The pantograph height measuring device according to claim 1, wherein the shape of the region is set.
3. The photographing line correction member has an upper and lower width at the center in the horizontal direction of the first color region so that the first color region is in contact with the adjacent first color region at the center in the horizontal direction. 3. The pantograph height measuring device according to claim 2, wherein said pantograph height measuring device is formed wider than the vertical width on both sides thereof.
4. The image processing means
   An input image creating unit for creating an input image in which image signals inputted from the line sensor are arranged in time series;
   A binarization processing unit for creating a binarized image obtained by binarizing the input image;
   A color area position detection unit for detecting positions of the dark color area and the light color area on the binarized image;
   A relational expression calculation unit that calculates the relational expression based on the positions of the dark color area and the light color area on the binarized image and the actual positions of the dark color area and the light color area; The pantograph height measuring device according to any one of claims 1 to 3.
5. The pantograph height measuring device according to claim 1, wherein the photographing line correction member has a center line at the center in the horizontal direction of the photographing line correction member.
6. A calibration method for a pantograph height measuring device, which takes a pantograph of the vehicle that is running by a line sensor installed on the roof of the vehicle, analyzes the image taken by the line sensor, and measures the height of the pantograph Because
   A first step of installing a calibration member in which dark areas and light-color areas are alternately arranged in the vertical direction on the surface in the vicinity of the pantograph;
   A second step of photographing the calibration member by the line sensor;
   In the image processing means, the positions of the dark color region and the light color region on the image photographed by the line sensor are detected, and the detected positions of the dark color region and the light color region on the image and the dark color are detected. A calibration method for a pantograph height measuring apparatus, comprising: a third step of calculating a relational expression between the area and the actual position of the light-colored area.
7. A first color region formed by connecting a plurality of regions having the same shape in the vertical direction and a second color region arranged around the first color region are arranged in color, and the first color region and the first color region Shooting line correction in which the second color area is arranged so that the widths of the first color area and the second color area displayed on the display unit change depending on the position and inclination of the shooting line of the line sensor. Installing a member for calibration on the member for calibration,
   Photographing the photographing line correction member by the line sensor,
   Correcting the shooting line while checking the image of the shooting line correction member displayed on the display means for displaying the image shot by the line sensor,
   After removing the photographing line correction member,
   The calibration method for a pantograph height measuring apparatus according to claim 6, wherein the first, second and third steps are performed.
8. The photographing line correction member has an upper and lower width at the center in the horizontal direction of the first color region so that the first color region is in contact with the adjacent first color region at the center in the horizontal direction. 8. The calibration method for a pantograph height measuring apparatus according to claim 7, wherein the width is formed wider than the vertical width on both sides thereof.
9. The image processing means
   Create an input image in which the image signals input from the line sensor are arranged in time series,
   Creating a binarized image obtained by binarizing the input image;
   Detecting the positions of the dark color region and the light color region on the binarized image;
   7. The relational expression is calculated based on positions of the dark color region and the light color region on the binarized image and actual positions of the dark color region and the light color region. 9. A calibration method for a pantograph height measuring device according to any one of items 8 to 9.
10. A center line is provided at the center in the horizontal direction of the photographing line correction member,
    The calibration method for a pantograph height measuring apparatus according to claim 6, wherein the photographing line is corrected based on the center line.

Images