JP2003246266A - Instrument for measuring attack angle in curved line passing of rolling stock - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an instrument for measuring an attack angle in the curved line passing of a rolling stock easy to use and capable of lowering costs. <P>SOLUTION: The measuring instrument is equipped with a pair of image- pickup devices 24 installed at the front and rear of the bottom of a rolling stock with respect to the rolling stock's moving direction in such a way that their relative positions do not change, a lighting device 25 that lights portions of which the pictures are taken by the pair of image-pickup devices 24, and a computer connected with the pair of image-pickup devices, while the pair of image-pickup devices 24 detect edges 23 of the shoulders of the rails, which shine in the form of a strip in reflection of the light, measuring relative right and left displacements by the computation of the computer, of the detected edges 23 of the shoulders of the rails, thereby detecting, from intervals of the installed pair of image-pickup devices 24, the attack angle of the vehicle equipped with the pair of image-pickup devices 24. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an attack angle measuring device for a railway vehicle, and more particularly to an attack angle measuring device for a railway vehicle passing through a curved line, focusing on a belt-like shining portion produced by polishing a rail shoulder. Is.

[0002]

2. Description of the Related Art Conventionally, as a technique in such a field, there is one disclosed in Japanese Patent Publication No. 3148437.

FIG. 8 is a block diagram showing such a conventional rail vehicle rail position measuring device, FIG. 9 is a side view showing the attack angle measuring device of the railway vehicle, and FIG. 10 is a plan view omitting the bogie frame of FIG. Is.

In these figures, an attack angle measuring device measures the relative position between a wheel 102 supported by an axle box 104 via an axle and a rail 101.
The light beam from 9 passes through the projection lens 110 and the rail 1
01, the scattered light of the linear light projection beam is condensed by the light receiving lens 112 to form an image on the line sensor 113, and each light receiving pixel of this line sensor 113 outputs an electric signal according to the amount of incident light. Detection head 114
Is arranged right above the rail 101 with the wheel 102 interposed therebetween at right angles to the axle, and the electric signal output from each light receiving element is input to the arithmetic means 121 to obtain information based on a plurality of positions on the inner side surface of the rail 101 and their intervals. From wheels 102 and rails 101
Calculate the angle formed by. In addition, 102a is an axle, 103 is a bogie frame, 103a is a spring, 108 is a projection pattern, 11
1 is a cylindrical concave lens, 114 is a detection head, 115 is a signal cable, 116 is a light source drive circuit, 117 is an A / D converter, 118 is a memory, 119 is a CPU, 120 is an output interface, 121 is each signal processing unit, Reference numeral 122 is a holding frame, and 123 is an attack angle calculation device.

Further, in the attack angle measuring device, the light beam of the light source 109 of the detection head 114 is turned on / off at a predetermined cycle, and the arithmetic means 121 obtains the difference between the signals during the lighting period and the extinguishing period, and the obtained difference is calculated. It is processed as a light receiving signal of a pixel, and the angle formed by the wheel 102 and the rail 101 is calculated from information based on a plurality of positions on the inner side surface of the rail 101 and the intervals thereof.

Here, 2 attached to the front and rear of the axle box 104
An attack angle measuring method based on the rail shape has been developed by capturing an image of the rail with a single camera 114, performing image processing to capture the rail cross-sectional shape by a method called a light section method.

[0007]

However, in the above-described conventional attack angle measuring method for a railway vehicle, accurate measurement cannot be performed unless the positional relationship between the camera and the illumination is strictly determined, so that the mounting equipment is expensive. Moreover, there is a drawback that the image processing method must be complicated.

SUMMARY OF THE INVENTION In view of the above situation, an object of the present invention is to provide a simple and cost-effective attack angle measuring device for a railway vehicle when passing a curve.

[0009]

In order to achieve the above object, the present invention provides: [1] In an attack angle measuring device for a railway vehicle when passing through a curved line, the relative positions are provided in front of and behind the bottom of the vehicle in the traveling direction of the vehicle. The image pickup device includes a set of image pickup devices that are mounted so as not to change, an illumination device that illuminates a region imaged by the set of image pickup devices, and a computer that is connected to the set of image pickup devices. Each of the devices detects the end of the rail shoulder that shines in a strip shape, and the arithmetic processing by the computer measures the relative lateral displacement of the detected end of the rail shoulder, from the mounting interval of the one set of imaging devices. An attack angle of a vehicle to which the set of image pickup devices is attached is detected.

[2] In the apparatus for measuring an attack angle of a railway vehicle when passing through a curved line according to the above [1], the bottom of the vehicle is a bogie or an axle box.

[3] In the attack angle measuring device for passing a curved line of a railway vehicle according to the above [1], irradiation light from the illuminating device is light having directivity.

As described above, according to the present invention, the lateral displacement of the rail viewed from the trolley side is based on the image data obtained by the two cameras attached to the front and rear of the trolley (or axle box) of the railway vehicle. (Relative left / right displacement on the two cameras) is measured, and the truck (axle box) attack angle is calculated therefrom.

That is, the attack angle detection is realized by capturing the reflected light of the rail shoulder with a camera and capturing the edge of the rail shoulder on the image by an image processing calculation on a computer. The key points here are (1) the arrangement of the camera and lighting to capture the reflected light from the rail shoulder, and (2) the edge of the rail shoulder detected from the image obtained above, and this rail shoulder is detected. Since the edge of the part is obtained by the front and rear two cameras in the same manner, the attack angle is calculated based on this edge.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below.

As described above, according to the present invention, the railcars (or axle boxes) mounted on the bottom of the bogie (or axle box) of the railcar are attached to the front and rear.
Based on the image data obtained by the two cameras, the lateral displacement of the rail (relative lateral displacement on the two cameras) as seen from the side of the bogie (or axle box) is measured, and from that, the bogie (axle box) Calculate the attack angle.

A feature of the present invention is that during the passage of a curve,
Generally, the attack angle of the wheel is large with respect to the rail,
Focusing on the fact that the rail shoulder is polished and shining in a strip shape, the camera captures the reflected light at the end (edge) of the rail shoulder that shines in a strip shape, and the edge on the image of the rail shoulder is displayed on the computer. By capturing by processing calculation, the lateral displacement of the rail (relative lateral displacement on the two cameras) seen from the dolly (or axle box) side is detected, and the attack angle in the curve is simply measured. Especially.

Here, the points are (1) the arrangement of the camera and its illuminating device for capturing the reflected light of the rail shoulder, and (2) detecting the end of the rail shoulder from the image obtained above. However, since the end of the rail shoulder is obtained by the front and rear two cameras in the same manner, the attack angle is calculated based on the end of the rail shoulder.

FIG. 1 is an overall configuration diagram of an attack angle measuring device for a railway vehicle when a vehicle is passing a curve according to an embodiment of the present invention.

In this figure, 1 is a first image pickup device (camera), 2 is a first illumination device, 3 is a second image pickup device (camera), 4 is a second illumination device, and 5 is a first illumination device. Displacement meter, 6 is a second displacement meter, 7 is a sensor-related device (point marker, speedometer, lateral pressure gauge, wheel scale, etc.), 10 is a computer (personal computer), 11 is its processing device, and an image processing board. 1
2, an A / D board 13, a D / A board 14, and the like.

Incidentally, the first displacement meter 5 and the second displacement meter 6
If a laser displacement meter is used and the trolley is equipped with cameras 1 and 3, it is attached to measure the displacement of the left and right axle boxes with respect to the trolley frame, and the yaw angle of the wheel axle (around the vertical axis) Angle).

The construction of each part of the attack angle measuring device for a railway vehicle of the present invention when passing through a curve will be described below.

FIG. 2 is a schematic view showing the arrangement of the rail, camera, and lighting device of the attack angle measuring device when the railway vehicle of the present invention passes through a curve.

In this figure, 21 is a rail, 22 is a shoulder portion of the rail (a portion which is shined by being polished by passing a curved line),
Reference numeral 23 denotes an end (edge) of the rail shoulder portion, 24 denotes a camera arranged above the rail shoulder portion 22 and below the vehicle, 2
Reference numeral 5 denotes an illuminating device which is disposed on the lower side of the vehicle on the diagonal side of the rail shoulder portion 22, and it is desirable that the illuminating device 5 emits light having more directivity. The reason for this is that by irradiating the vicinity of the rail shoulder portion 22, it is possible to obtain the accurate imaging information of the rail shoulder portion 22 by preventing emission of light emitted by a reflection object other than the portion of the rail shoulder portion 22. Is desirable. However, since the relative positions of the rail 21, the camera 24, and the lighting device 25 change according to the running state,
It goes without saying that it is necessary to consider a certain illumination range so as to compensate for the change.

26 is a tangent to the end 23 of the rail shoulder,
Reference numeral 27 indicates a normal line to the tangent line 26. Since the rail shoulders are rounded, there is an advantage that the camera 24 and the lighting device 25 can be positioned with sufficient margin.

In this embodiment, as shown in FIG. 2, the light emitted from the illumination device 25 is specularly reflected by the rail shoulder portion 22 and the light is captured at the center of the camera 24. . That is, α1 = α2.

More specifically, the rail on the outer gauge side in the curve is polished so that the shoulder 22 inside the rail shines when the vehicle runs. This rail shoulder 22 is normally a radius of ten and several mm
It has a curved cross section. The camera 24 is arranged so as to be photographed from directly above the rail for measurement, and the illumination device 25 is attached so that the camera 24 is directed toward the rail shoulder portion 22 in a direction in which the rail shoulder portion 22 is regularly reflected.

At this time, the direction of specular reflection with respect to the point light source can be set only on one line, and theoretically the positional relationship among the camera 24, the lighting device 25, and the rail 21 is absolutely determined. The illumination device 25 used practically is a surface light source, and the regular reflection direction has a fan shape with some angle, the rail shoulder 22 has a curved surface with a certain width, and it is not a perfect mirror surface to some extent. Therefore, the positional relationship between the camera 24, the lighting device 25, and the rail 21 has a certain degree of deviation from the ideal state. This is the greatest feature, and the attack measuring device of the present invention can be practically implemented. The fact that the lighting device is a surface light source also makes it possible to mount the lighting device 25, which is practically low in vibration resistance, to a vehicle body that moves differently from the bogie frame to which the camera 24 is mounted. This is limited to the case where the relative displacement between the vehicle body and the bogie is within a practically permissible range.

FIG. 3 is a schematic view showing the arrangement of cameras according to the first embodiment of the present invention.

In this embodiment, a first camera 35 and a second camera 36 are arranged in front of and behind a chassis 34 having wheels 32 and 33 before and after traveling on a rail 31. Here, the distance between the first camera 35 and the second camera 36 is L ₁ .

FIG. 4 is a schematic view showing the arrangement of cameras according to the second embodiment of the present invention.

In this embodiment, the first camera 35 and the second camera 36 are arranged so as to sandwich only the rear wheel 33 of the chassis 34 having the front and rear wheels 32, 33 traveling on the rail 31. . Here, the first camera 35
And the distance between the second camera 36 and L ₂ is L ₂ .

In the case of the second embodiment, as will be described later, the conversion for determining the attack angle is the first conversion shown in FIG.
It is easier than in the case of the embodiment.

FIG. 5 is a schematic view showing the arrangement of cameras according to the third embodiment of the present invention, and FIG. 6 is a plan view with the bogie frame omitted.

In this embodiment, the first camera 44 and the second camera 45 are arranged on the axle box 43 of the wheel 42 traveling on the rail 41 so as to be in front of and behind the wheel 42. There is. Here, the distance between the first camera 44 and the second camera 45 is L ₃ . Note that 43A is a holding frame, 46 is a first lighting device, and 47 is a second lighting device.

In this case, the first camera 4 is attached to the axle box 43.
4 and the second camera 45 are attached, the conversion when obtaining the attack angle will be described later with reference to FIGS.
It is easier than the case where the first camera 35 and the second camera 36 are attached to the truck as in the first and second embodiments shown in FIG.

FIG. 7 is a diagram showing a rail image during running captured by the first camera and the second camera, showing the embodiment of the present invention.

In this figure, 51 is a rail, 52 is a rail shoulder portion (shining portion), and 53 is an end (edge) of the rail shoulder portion 52.

Next, a method of measuring the attack angle of the railcar of the present invention when passing through a curve will be described.

First, the wheel shaft attack angle ψ _A is ψ _A = ψ _T + ψ _W ± ψ _R , and ± in the third term indicates the attack angle of the front shaft with respect to the traveling direction of the biaxial bogie truck. Is +, and in the case of the rear shaft, − is used.

Next, the trolley attack angle ψ _T obtained by the camera and image processing is obtained by the following equation.

Ψ _T = tan ^-1 [(Y _TF -Y _TR ) / L] where Y _TF is the rail relative lateral displacement of the carriage measured by the camera before the carriage and Y _TR is the rail of the carriage measured by the camera after the carriage. The relative lateral displacement L is a camera position attachment distance before and after the truck.

The relative yaw angle ψ _W between the wheel axle and the bogie is determined by the following equation by measuring the longitudinal displacement of the axle boxes on the left and right of the axis of symmetry.

Ψ _W = tan ^-1 [(X _WA -X _WB ) / _bb ] where _bb is the left-right axis box interval.

Next, the curvature correction term ψ _R will be described.

When the attack angle of the wheelset is obtained based on the attack angle of the truck running on a curve, the tangential direction of the curve changes by the offset (substantially the wheelbase) between the center of the truck and the center of the wheelset. This is corrected by the following formula. Strictly speaking, it is the following formula.

Ψ _R = tan ^-1 [2R {1-cos [si
n ^-1 (a / R)]} / a] Here, a is 1/2 of the bogie axle distance, and R is a curve radius.

However, the following equation is approximately sufficient. In practice, this approximation causes an error at the fifth significant digit.

Ψ _R = tan ⁻¹ (a / R) In the above equation, the curvature in the circular curve is constant, but the curvature in the relaxation curve is the relaxation curve length X and the center of the bogie from the relaxation curve entrance. It is expressed by the following equation using the distance X _T (distance from the zero curvature side).

1 / R = 1 / R _C [(X _T ± a) / X] ± in the above equation is on the side where the measurement axis has a small curvature with respect to the center of the bogie (that is, the side closer to the circular curve). In this case, + is used, and when it is on the side with a large curvature (that is, a straight line), − is used.

In the embodiment of the present invention, a commonly used edge detection algorithm can be used.
In other words, the measurement item is the attack angle (not the relative displacement of the rail) on the assumption that the images obtained by the front and rear two cameras are similar even with such a simple method, and This method works effectively because the relative difference in the obtained position information is necessary information.

(1) Attack angle calculation method (when a camera is attached to the bogie frame) ψ _A = tan ⁻¹ [(Y _TF −Y _TR ) / L] + tan ⁻¹ [(X _WA −X _WB ) / b _b ] + ψ _R (1) where ψ _A is the trolley-wheel axle relative attack angle calculated from the relative longitudinal displacement of the trolley-wheel axle from the laser displacement meter attached to the trolley, and ψ _R is the curvature correction term in the curve. , Approximately,
It is determined from the above-mentioned ψ _R = tan ⁻¹ (a / R).

The curve radius must be known in order to obtain this correction term. At present, in a yard driving test using this measurement method, point information can be easily obtained. In this case as well, it is necessary to define the curvature in the relaxation curve, but this is also possible if only the point information at the time of data collection can be recorded.
The curvature in the relaxation curve can also be determined.

However, the curvature correction term ψ _R is not required in the second camera mounting example shown in FIG.

In the third camera mounting example shown in FIG. 5, the carriage-wheel axle relative attack angle ψ _A and the curvature correction term ψ _R are not required.

(2) Indirect measurement method of wheel axle attack angle The trolley attack angle is measured from two cameras mounted on the trolley frame, and the trolley attack angle is measured as an absolute value. The symmetrical wheel axle attack angle is indirectly measured. The method is the camera mounting example shown in FIGS. 3 and 4.

(3) Direct measurement method of wheel shaft attack angle FIG. 5 shows the wheel shaft attack angle measured by two cameras mounted on a shaft box.

In the camera mounting example of FIGS. 3 and 4, the carriage 34 is used.
The attack angle of is measured and the attack angle of the wheel axle is calculated from the measured attack angle. The most direct way to obtain the attack angle of the wheel axle is to mount it like the third camera mounting example shown in FIG. 5, but since the camera is mounted under the spring, Vibration durability becomes a problem, and the measurement accuracy becomes a problem due to the resolution of the camera. Therefore, an experiment was conducted with reference to FIG.

The difference between the methods shown in FIGS. 3 and 4 will be described. In FIG. 3, the trolley attack angle with respect to the curved tangential direction at the trolley center is measured. It can be said that the setting shown in FIG. 3 is more preferable for obtaining the trolley attack angle.

However, in the case where the trolley attack angle is obtained in order to indirectly obtain the wheel axle attack angle, it can be considered as shown in FIG. In FIG. 4, the cameras are attached to the bogie frame, but the front and rear cameras can be attached at equal intervals from the wheel axle center of the object to be measured, so the bogie attack angle with respect to the curved tangential direction at the wheel axle center position is obtained. With this method, the curvature correction term ψ _{R in} equation (1)
Has the advantage that it can be omitted. Further, as for the trajectory deviation, the tracking of FIG. 4 can be performed with higher accuracy than that of FIG. However, in the camera mounting example of FIG. 4, there are restrictions on the arrangement of various parts around the carriage, and it may be difficult to implement. Further, the rail displacement at the front and rear camera positions may be smaller than that in the camera mounting example of FIG. 3, and the measurement accuracy may be reduced.

The present invention is not limited to the above embodiments, and various modifications can be made based on the spirit of the present invention, and these modifications are not excluded from the scope of the present invention.

[0061]

As described above in detail, according to the present invention, it is possible to easily and inexpensively measure the attack angle of a railway vehicle when it passes through a curve.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an attack angle measuring device when a railway vehicle passes a curve according to an embodiment of the present invention.

FIG. 2 is a schematic view showing the arrangement of a rail, a camera, and a lighting device of an attack angle measuring device when the railway vehicle of the present invention passes through a curve.

FIG. 3 is a schematic diagram showing an arrangement of cameras according to the first embodiment of the present invention.

FIG. 4 is a schematic diagram showing an arrangement of cameras according to a second embodiment of the present invention.

FIG. 5 is a schematic diagram showing an arrangement of cameras according to a third embodiment of the present invention.

6 is a plan view in which the bogie frame in FIG. 5 is omitted.

FIG. 7 is a diagram showing a rail image during traveling which is actually captured by the first camera and the second camera according to the embodiment of the present invention.

FIG. 8 is a configuration diagram showing a conventional rail position measuring device for a railway vehicle.

FIG. 9 is a side view showing a conventional attack angle measuring device for a railway vehicle.

FIG. 10 is a plan view with the bogie frame of FIG. 9 omitted.

[Explanation of symbols]

1, 35, 44 1st imaging device (camera) 2, 46 1st illumination device 3, 36, 45 2nd imaging device (camera) 4, 47 2nd illumination device 5 1st displacement meter 6 2 Displacement gauge 7 Sensor related equipment (point marker, speedometer, lateral pressure gauge, wheel scale, etc.) 10 Computer (personal computer) 11 Processor 12 Image processing board 13 A / D board 14 D / A board 21, 31, 41 , 51 rails 22, 52 rail shoulders (portions that are shining after being polished by a curve) 23, 53 rail shoulder ends (edges) 24 camera 25 lighting devices 32, 33 front and rear wheels 34 chassis 42 wheels 43 axle box 43A holding flame

Claims (3)

[Claims] 1. A set of image pickup devices mounted so that a relative position does not change before and after a bottom of a vehicle in a vehicle traveling direction, and (b) Illuminates a part imaged by the set of image pickup devices. An illumination device and (c) a computer connected to the one set of image pickup devices are provided, and (d) an edge of a rail shoulder shining in a strip shape is detected by the one set of image pickup devices, and a calculation process by the computer is performed. By measuring the relative lateral displacement of the detected ends of the rail shoulders, the attack angle of the vehicle to which the one set of image pickup devices is attached is detected from the mounting interval of the one set of image pickup devices. A device for measuring the attack angle of a rolling stock that passes through a curve. 2. The attack angle measuring apparatus for a railway vehicle when passing through a curved line according to claim 1, wherein the bottom of the vehicle is a bogie or an axle box. apparatus. 3. The railway vehicle attack angle measuring device for passing a curved line according to claim 1, wherein the irradiation light from the lighting device is a light having directivity. Attack angle measuring device.