Train stop detection device

Abstract

To provide a train stop detection device capable of enhancing the accuracy of detecting whether and where a train has stopped.SOLUTION: A train stop detection device 1 is mounted on a platform 3 of a railway station and detects whether a train 100, in which multiple railway vehicles 101 are coupled, has stopped and at which position the train 100 has stopped. The train stop detection device 1 includes a first radar sensor 11, a second radar sensor 12, a first stereo camera 21, and a second stereo camera 22.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a train stop detection device. In particular, the present disclosure relates to a train stop detection device that detects the stop of a train and the stopping position of the train as an auxiliary device of a platform door. [Background technology]

[0002] In recent years, many platform doors have been installed on train station platforms. For safety reasons, it is desirable to open the platform doors only when the train stops within a predetermined range. For this reason, devices that are installed on platforms and detect when a train has stopped and where the train is stopped are known. For example, the devices described in Patent Documents 1 and 3 scan a laser beam toward a train's car coupling to measure the distance to the end of the car, and determine the positional relationship between the car coupling and a predetermined fixed position range based on the distance. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6000488 [Patent Document 2] Patent No. 6081549 [Patent Document 3] JP 2012-046123 A [Patent Document 4] JP 2015-147481 A Summary of the Invention [Problem to be solved by the invention]

[0004] There are several problems with the configuration of detecting the train's stopping position by scanning a laser beam toward the train, as in the devices described in Patent Documents 1 and 3 mentioned above. First, when the surface color of the vehicle is a dark color such as black, the intensity of the light reflected from the vehicle surface is low, and therefore the accuracy of measuring the distance is reduced. As a result, the accuracy of detecting that the train has stopped and the train's stopping position may be reduced. Also, when the light reflectance of the vehicle surface is high due to a mirror finish or the like, the irradiated laser beam may be reflected in a direction completely different from the measuring device, and therefore the distance may not be measured. As a result, it may be impossible to detect that the train has stopped and the train's stopping position.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a train stop detection device that can improve the accuracy of detecting when a train has stopped and where the train is stopping. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, [1] a train stop detection device according to the present disclosure is installed on a platform of a railway station and detects when a train consisting of multiple coupled railway cars has stopped and where the train is stopping, and includes a first stereo camera that captures an image of a predetermined portion of at least one of the railway cars and outputs first disparity data, a second stereo camera that captures an image of a predetermined portion of the at least one of the railway cars and outputs second disparity data, and a processing unit that determines whether the train has stopped and generates information regarding the train's stopping position based on one or both of first information regarding whether the train has stopped and where the train is stopping, which is generated based on the first disparity data, and second information regarding whether the train has stopped and where the train is stopping, which is generated based on the second disparity data.

[0007] The train stop detection device of [1] above includes stereo cameras (first and second stereo cameras). Since the stereo cameras do not emit laser light, they are not easily affected by the surface color of the vehicle or the light reflectance of the vehicle surface. Therefore, the above-mentioned drawbacks of distance measurement using laser light can be overcome. In addition, the stereo cameras may be affected by disturbance light such as sunlight, making the measurement unstable. Therefore, in the train stop detection device of [1] above, the processing unit determines whether the train has stopped based on information from one or both of the two stereo cameras, i.e., the first stereo camera and the second stereo camera, and generates information regarding the stopping position of the train. This makes it possible to accurately detect that the train has stopped and the stopping position of the train while suppressing the influence of disturbance light such as sunlight.

[0008] [2] In the train stop detection device of [1] above, the installation height of the first stereo camera relative to the platform may be different from the installation height of the second stereo camera relative to the platform. In that case, in order to photograph the same predetermined portion, the inclination angles of the optical axis of the lens of the first stereo camera and the optical axis of the lens of the second stereo camera are different from each other. This makes it possible to prevent the first stereo camera and the second stereo camera from being simultaneously affected by ambient light such as sunlight.

[0009] [3] In the train stop detection device of [2] above, the processing unit may determine whether the train has stopped and generate information related to the train's stopping position based on the first information during a first time period, and may determine whether the train has stopped and generate information related to the train's stopping position based on the second information during a second time period different from the first time period. In this case, it is possible to preferably determine whether the train has stopped and measure the stopping position while avoiding the influence of external light (e.g., sunlight) that changes depending on the time period.

[0010] [4] In the train stop detection device according to any one of the above [1] to [3], at least one of an axis line connecting the two cameras constituting the first stereo camera and an axis line connecting the two cameras constituting the second stereo camera may be parallel to the platform. In this case, the installation work of the first stereo camera and the second stereo camera can be easily performed.

[0011] [5] In the train stop detection device according to any one of the above [1] to [3], at least one of the axis lines connecting the two cameras constituting the first stereo camera and the axis lines connecting the two cameras constituting the second stereo camera may be inclined with respect to the platform. In this case, the brightness difference between pixels in the horizontal direction increases, and the number of detected disparity data increases. Therefore, at least one of the first information and the second information can be generated with higher accuracy, and the accuracy of detecting the stop of the train and the stopping position of the train can be further improved.

[0012] [6] In the train stop detection device of any one of [1] to [5] above, the predetermined portion may include a part of the side surface of the front railcar of two railcars coupled to each other, a part of the side surface of the rear railcar of the rear railcar of the two railcars coupled to each other, and at least a part of the side surface of the gangway canopy connecting the two railcars. In the stereo image, the difference between the distance to the side surfaces of the front and rear railcars and the distance to the side surface of the gangway canopy is one of the most characteristic parts that can be used to determine the position of the train. Therefore, according to the train stop detection device of [6] above, it is possible to further improve the accuracy of detecting that the train has stopped and the stopping position of the train.

[0013] [7] In the train stop detection device according to any one of the above [1] to [6], one or both of the first and second stereo cameras may be installed facing diagonally downward. In this case, the influence of disturbance light such as sunlight can be reduced.

[0014] [8] In the train stop detection device according to any one of [1] to [7] above, the processing unit may determine whether the train's stopping position is within a predetermined range when it is determined that the train has stopped. In this case, for example, a device that controls the opening and closing of platform doors can receive a signal from the processing unit regarding whether the train's stopping position is within the predetermined range and determine whether the platform doors are opened or closed. Effect of the Invention

[0015] According to the train stop detection device of the present disclosure, it is possible to improve the accuracy of detecting that a train has stopped and the stopping position of the train. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a diagram showing a train stop detection device according to an embodiment of the present disclosure installed on a platform of a railway station. [Diagram 2] FIG. 2 is a front view of the train stop detection device. [Diagram 3] FIG. 3 is a plan view showing how radio waves are emitted from the first radar sensor and the second radar sensor toward a train. [Figure 4] FIG. 4 is a diagram showing a measurement target portion of the first radar sensor. [Diagram 5] FIG. 5 is a diagram showing a measurement target portion of the second radar sensor. [Figure 6] FIG. 6 is a plan view showing the shooting ranges of the first stereo camera and the second stereo camera. [Figure 7] FIG. 7 is a perspective view showing a target portion imaged by the first stereo camera and the second stereo camera. [Figure 8] FIG. 8 is a side view showing a target portion imaged by the first stereo camera and the second stereo camera. [Figure 9] FIG. 9 is a front view showing the first stereo camera and the second stereo camera. [Figure 10] FIG. 10 is a front view showing the first stereo camera and the second stereo camera. [Figure 11] FIG. 11 is a side view showing the first stereo camera and the second stereo camera. [Figure 12] FIG. 12 is a block diagram showing the system configuration of the train stop detection device. [Figure 13] FIG. 13 is a flowchart showing the operations of the first radar sensor, the second radar sensor, and the calculation unit. [Figure 14] FIG. 14 is a flowchart showing the operation of the first stereo camera (or the second stereo camera) and the calculation unit. [Figure 15] FIG. 15 is a diagram conceptually showing the overall judgment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of a train stop detection device according to the present disclosure will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements are given the same reference numerals, and duplicated descriptions will be omitted. In the drawings, an XYZ orthogonal coordinate system is shown as necessary. In the following description, the traveling direction of the train is defined as the X direction, and the vertical upward direction is defined as the Z direction.

[0018] FIG. 1 is a diagram showing a train stop detection device 1 according to an embodiment of the present disclosure installed on a platform 3 of a railway station. FIG. 2 is a front view of the train stop detection device 1. The train stop detection device 1 is a device for detecting that a train 100, to which a plurality of railcars 101 are coupled, has stopped and the stopping position of the train 100. The train stop detection device 1 is fixed to a structure such as a roof 4 installed on the platform 3, for example. The installation height of the train stop detection device 1 based on the platform 3 is higher than the height of the upper end of the door of the railcar 101, for example. The train stop detection device 1 includes a first radar sensor 11, a second radar sensor 12, a first stereo camera 21, and a second stereo camera 22.

[0019] The first radar sensor 11 and the second radar sensor 12 are fixed to a structure such as the roof 4 by mounting mechanisms 11b and 12b, respectively. The first radar sensor 11 and the second radar sensor 12 emit radio waves toward the railcar 101 and measure the reflected waves to measure the distance and direction to the railcar 101. As shown in FIG. 2, the first radar sensor 11 and the second radar sensor 12 are arranged side by side along the traveling direction (X direction) of the train 100. The emission directions of the radio waves of the transmitter 11a of the first radar sensor 11 and the transmitter 12a of the second radar sensor 12 intersect with each other. In other words, the transmitter 11a of the first radar sensor 11 faces diagonally forward, and the transmitter 12a of the second radar sensor 12 faces diagonally backward. In one example, the installation heights of the transmitters 11a and 12a relative to the platform 3 are equal to each other. The first radar sensor 11 and the second radar sensor 12 may have the same configuration as each other except for the installation position and orientation. In the traveling direction (X direction) of the train 100, the first radar sensor 11 is disposed behind the second radar sensor 12.

[0020] Fig. 3 is a plan view showing how radio waves RW are emitted from the first radar sensor 11 and the second radar sensor 12 toward the train 100. Fig. 3 shows a state in which the train 100 has stopped at a specified stopping position, and shows two adjacent railcars 101A and 101B of the train 100. As shown in Fig. 3, the first radar sensor 11 and the second radar sensor 12 are disposed at positions where the radio waves RW will hit the car coupling parts 102 of the two adjacent railcars 101A and 101B when the train 100 has stopped at the specified stopping position. As shown in the illustrated example, the distance W1 between the first radar sensor 11 and the second radar sensor 12 in the traveling direction (X direction) of the train 100 is preferably larger than the distance W2 between the end face (i.e., rear end face) 103 of the leading railcar 101A facing the trailing railcar 101B and the end face (i.e., front end face) 104 of the trailing railcar 101B facing the leading railcar 101A. In addition, the first radar sensor 11 and the second radar sensor 12 are preferably arranged such that, when the train 100 is stopped at a specified stopping position, a virtual plane H1 equidistant from both the end face 103 of the leading railcar 101A and the end face 104 of the trailing railcar 101B coincides with a virtual plane H2 equidistant from both the first radar sensor 11 and the second radar sensor 12.

[0021] FIG. 4 is a diagram showing a measurement target portion 121 of the first radar sensor 11. The measurement target portion 121 of the first radar sensor 11 includes at least one of the end face 103 of the front railcar 101A of the two railcars 101A and 101B coupled to each other and the edge (side) 106 between the end face 103 and the side face 105 of the front railcar 101A. In this specification, the measurement target portion including the end face does not necessarily mean that the measurement target portion includes the entire end face, but means that the measurement target portion includes at least a part of the entire end face. FIG. 4 illustrates a case where the measurement target portion 121 includes a part of the area 103a of the entire end face 103 that is closer to the roof and closer to the edge 106. The first radar sensor 11 outputs a distance measurement signal (first distance measurement signal) related to the distance to the measurement target portion 121.

[0022] 5 is a diagram showing a measurement target portion 122 of the second radar sensor 12. The measurement target portion 122 of the second radar sensor 12 includes at least one of the end face 104 of the rear railway car 101B of two railway cars 101A, 101B coupled to each other and the edge (side) 108 between the end face 104 and the side surface 107 of the rear railway car 101B. FIG. 5 illustrates a case in which the measurement target portion 122 includes a partial area 104a of the entire end face 104 that is closer to the roof and closer to the edge 108. The second radar sensor 12 outputs a distance measurement signal (second distance measurement signal) related to the distance to the measurement target portion 122.

[0023] 1 and 2 are referred to again. The first stereo camera 21 has two cameras, and simultaneously photographs the railcars 101A and 101B from different directions, and outputs parallax data related to the position in the depth direction of the image based on the difference in parallax between the two cameras. Similarly, the second stereo camera 22 has two cameras, and simultaneously photographs the railcars 101A and 101B from different directions, and outputs parallax data related to the position in the depth direction of the image based on the difference in parallax between the two cameras. The first stereo camera 21 and the second stereo camera 22 take images using natural light or ambient light without irradiating light. Therefore, even if the surface color of the vehicle is a dark color such as black, or the light reflectance of the surface of the vehicle is high due to a mirror finish, etc., distance measurement with sufficient accuracy is possible. As shown in FIG. 2, the first stereo camera 21 and the second stereo camera 22 are located between the first radar sensor 11 and the second radar sensor 12 in the traveling direction (X direction) of the train 100. The first stereo camera 21 and the second stereo camera 22 are arranged side by side along the Z-axis direction. The installation height of the first stereo camera 21 with respect to the platform 3 as a reference and the installation height of the second stereo camera 22 with respect to the platform 3 as a reference are different from each other.

[0024] FIG. 6 is a plan view showing the imaging range Q of the first stereo camera 21 and the second stereo camera 22. FIG. 6 shows a state where the train 100 is stopped at a specified stop position, and shows two adjacent railcars 101A and 101B of the train 100. As shown in FIG. 6, the first stereo camera 21 and the second stereo camera 22 are disposed at positions where the imaging range includes the vehicle coupling portion 102 and its vicinity of the two adjacent railcars 101A and 101B when the train 100 is stopped at the specified stop position. In addition, as shown in the illustrated example, the first stereo camera 21 and the second stereo camera 22 are preferably disposed at positions overlapping with a virtual plane H1 that is equidistant from both the end face 103 of the front railcar 101A and the end face 104 of the rear railcar 101B when the train 100 is stopped at the specified stop position.

[0025] 7 and 8 are a perspective view and a side view showing an imaging target portion (predetermined portion) 130 of the first stereo camera 21 and the second stereo camera 22. The imaging target portion 130 of the first stereo camera 21 and the second stereo camera 22 includes a portion 105a, a portion 107a, and a portion 111a. The portion 105a is a part closer to the rear of the side surface 105 of the front railcar 101A of the two railcars 101A and 101B coupled to each other. The portion 105a may be a part closer to the rear and closer to the roof of the side surface 105. The portion 107a is a part closer to the front of the side surface 107 of the rear railcar 101B. The portion 107a may be a part closer to the front and closer to the roof of the side surface 107. The portion 111a is at least a part of the side surface 111 of the gangway hood 110 connecting the two railcars 101A and 101B. The portion 111a may be a part of the side surface 111 close to the roof. At least one of the portions 105a, 107a, and 111a may be a rectangular region with the traveling direction as a longitudinal direction. As shown in Fig. 8, the portion 105a may reach the edge 106, the portion 107a may reach the edge 108, and the portion 111a may reach both ends of the through-hole 110 in the traveling direction.

[0026] The first stereo camera 21 captures an image of the imaging target area 130 across the two railcars 101A and 101B, and outputs disparity data (first disparity data). Similarly, the second stereo camera 22 captures an image of the imaging target area 130 across the two railcars 101A and 101B, and outputs disparity data (second disparity data).

[0027] 9 and 10 are front views showing the first stereo camera 21 and the second stereo camera 22. In these figures, an axis AX1 connecting the two cameras 211 and 212 constituting the first stereo camera 21 and an axis AX2 connecting the two cameras 221 and 222 constituting the second stereo camera 22 are shown. At least one of these axes AX1 and AX2 may be parallel to the platform 3. FIG. 9 shows an example in which both the axis AX1 and the axis AX2 are parallel to the platform 3. In this case, the axis AX1 and the axis AX2 are parallel to each other. Alternatively, at least one of the axis AX1 and the axis AX2 may be inclined with respect to the platform 3. In other words, at least one of the first stereo camera 21 and the second stereo camera 22 may have a roll angle around the Y axis. FIG. 10 shows an example in which both the axis AX1 and the axis AX2 are inclined with respect to the platform 3. The inclination angle θ1 of the axis AX1 relative to the platform 3 may be the same as or different from the inclination angle θ2 of the axis AX2 relative to the platform 3. The positive and negative signs of the inclination angle θ1 may be the same as or different from the positive and negative signs of the inclination angle θ2. When the positive and negative signs of the inclination angle θ1 are opposite to those of the inclination angle θ2 and the absolute value of the inclination angle θ1 is equal to the absolute value of the inclination angle θ2, the axis AX1 and the axis AX2 viewed from the Y-axis direction are line-symmetrical with respect to a straight line along the Z-axis direction. In addition, the position of the first stereo camera 21 in the X-axis direction and the position of the second stereo camera 22 in the X-axis direction may be different from each other as shown in FIG. 10.

[0028] FIG. 11 is a side view showing the first stereo camera 21 and the second stereo camera 22. In these figures, the optical axis AX3 of the lens of the first stereo camera 21 and the optical axis AX4 of the lens of the second stereo camera 22 are shown. These optical axes AX3 and AX4 have inclination angles α1 and α2, respectively, with respect to the platform 3. The signs of the inclination angles α1 and α2 when the first stereo camera 21 and the second stereo camera 22 face obliquely downward are positive. At this time, α1>0, α2>0. That is, in this embodiment, the first stereo camera 21 and the second stereo camera 22 are installed so as to face obliquely downward. Note that this is not limited to this, and one of the first stereo camera 21 and the second stereo camera 22 may be installed so as to face obliquely downward. In addition, the magnitude of the inclination angle α1 and the magnitude of the inclination angle α2 are different from each other. In one example, the inclination angles α1 and α2 are adjusted so that the first stereo camera 21 and the second stereo camera 22, which are installed at different heights, face toward the same imaging target site 130.

[0029] Fig. 12 is a block diagram showing a system configuration of the train stop detection device 1. As shown in Fig. 12, the train stop detection device 1 includes a distance measurement unit 10 and a processing unit 30. The distance measurement unit 10 includes the above-mentioned first radar sensor 11, second radar sensor 12, first stereo camera 21, and second stereo camera 22. In the illustrated example, the processing unit 30 includes three calculation units 31, 32, and 33. The calculation units 31, 32, and 33 may be configured by a computer including, for example, a CPU, a volatile storage unit such as a RAM, and a non-volatile storage unit such as a ROM or a hard disk.

[0030] The calculation unit 33 is connected to the first radar sensor 11 and the second radar sensor 12 via a communication line, and receives a distance measurement signal S1 related to the distance to the measurement target portion 121 from the first radar sensor 11, and receives a distance measurement signal S2 related to the distance to the measurement target portion 122 from the second radar sensor 12. The calculation unit 33 generates information A1 related to the stopping of the train 100 and the stopping position of the train 100 based on the distance measurement signal S1 and the distance measurement signal S2. The calculation units 31 to 33 are connected to each other via a communication line 34, and the calculation unit 33 transmits the generated information A1 to each of the calculation units 31 and 32.

[0031] 13 is a flowchart showing the operation of the first radar sensor 11, the second radar sensor 12, and the calculation unit 33. As shown in FIG. 13, first, the first radar sensor 11 performs measurement and generates a distance measurement signal S1 (step ST11). At the same time, the second radar sensor 12 performs measurement and generates a distance measurement signal S2 (step ST12). Next, the calculation unit 33 generates composite data by combining the distance to the measurement target part 121 indicated in the distance measurement signal S1 and the distance to the measurement target part 122 indicated in the distance measurement signal S2 (step ST13). Next, the calculation unit 33 determines whether the measurement target parts 121 and 122 (i.e., the area 103a of the rear surface 103, the area 104a of the rear surface 104, the edge 106, and the edge 108) are included in the composite data (step ST14). If the measurement target parts 121, 122 are not included in the combined data (step ST15: NO), the calculation unit 33 repeats steps ST11 to ST15 again. If the measurement target parts 121, 122 are included in the combined data (step ST15: YES), the calculation unit 33 judges whether the railroad cars 101A, 101B have stopped (step ST17). If it is judged that the railroad cars 101A, 101B have not stopped (step ST17: NO), the calculation unit 33 repeats steps ST11 to ST17 again. If it is judged that the railroad cars 101A, 101B have stopped (step ST17: YES), the calculation unit 33 calculates the stopping position of the train 100 based on the installation positions of the first radar sensor 11 and the second radar sensor 12 and the distance data to the measurement target parts 121, 122. Then, the calculation unit 33 generates information A1 regarding the fact that the train 100 has stopped and the stopping position of the train 100 (step ST18).

[0032] Referring again to FIG. 12, the calculation unit 31 is connected to the first stereo camera 21 via a communication line, and receives from the first stereo camera 21 disparity data D1 obtained by the first stereo camera 21 capturing an image of the imaging target portion 130. The calculation unit 31 generates information (first information) A21 regarding the fact that the train 100 has stopped and the stopping position of the train 100 based on the disparity data D1. The calculation unit 31 transmits the information A21 to the calculation unit 32. The calculation unit 32 is connected to the second stereo camera 22 via a communication line, and receives from the second stereo camera 22 disparity data D2 obtained by the second stereo camera 22 capturing an image of the imaging target portion 130. The calculation unit 32 generates information (second information) A22 regarding the fact that the train 100 has stopped and the stopping position of the train 100 based on the disparity data D2. The calculation unit 32 transmits the information A22 to the calculation unit 31.

[0033] 14 is a flowchart showing the operation of the first stereo camera 21 (or the second stereo camera 22) and the calculation unit 31 (or the calculation unit 32). The operation of the first stereo camera 21 and the calculation unit 31 will be mainly described below, but the operation of the second stereo camera 22 and the calculation unit 32 is similar.

[0034] As shown in FIG. 14, first, the first stereo camera 21 captures images and generates parallax data D1 (step ST21). Next, the calculation unit 31 converts the parallax data D1 into distance data and determines whether or not the portion 105a of the side surface 105 of the front railcar 101A and the portion 107a of the side surface 107 of the rear railcar 101B of the imaging target portion 130 are included in the distance data. If the portion 105a and the portion 107a are not included in the distance data (step ST22: NO), the calculation unit 31 repeats steps ST21 and ST22 again. If the portion 105a and the portion 107a are included in the distance data (step ST22: YES), the calculation unit 31 determines whether or not the edge 106 and the edge 108 are included in the distance data (step ST23). If the edge 106 and the edge 108 are not included in the distance data (step ST24: NO), the calculation unit 31 repeats steps ST21 to ST24 again. If the edge 106 and the edge 108 are included in the distance data (step ST24: NO), the calculation unit 31 confirms that the portion 111a of the side surface 111 of the gangway hood 110 among the imaging target portion 130 is included in the distance data (step ST25). Even if the portion 111a is not included in the distance data, the process may proceed to a later step. Then, the calculation unit 31 judges whether the railcars 101A and 101B have stopped based on the distance data (step ST26). If the calculation unit 31 judges that the railcars 101A and 101B have not stopped (step ST26: NO), the calculation unit 31 repeats steps ST21 to ST27 again. If the calculation unit 31 judges that the railcars 101A and 101B have stopped (step ST27: YES), the calculation unit 31 calculates the stopping position of the train 100 based on the installation position of the first stereo camera 21 and the distance data to the portions 105a, 107a, and 111a. Then, the calculation unit 31 generates information A21 regarding the fact that the train 100 has stopped and the stopping position of the train 100 (step ST28).

[0035] In addition, when at least one of the axes AX1 and AX2 is inclined with respect to the platform 3 (see FIG. 10), in order to facilitate subsequent calculations, the calculation unit 31 may correct the parallax data by the inclination angle before calculating the distance data.

[0036] Here, the vehicle position state comprehensive judgment (hereinafter, comprehensive judgment) will be described. FIG. 15 is a diagram conceptually showing the comprehensive judgment. As described above, the distance measurement signal S1 from the first radar sensor 11 and the distance measurement signal S2 from the second radar sensor 12 are synthesized, and information A1 regarding whether or not the train 100 has stopped and the stopping position is generated from the synthesized data DA. Furthermore, information A21 regarding whether or not the train 100 has stopped and the stopping position is generated from the parallax data D1 from the first stereo camera 21. Furthermore, information A22 regarding whether or not the train 100 has stopped and the stopping position is generated from the parallax data D2 from the second stereo camera 22. The comprehensive judgment is to finally judge whether or not the train 100 has stopped based on at least one of the information A1, the information A21, and the information A22, and to generate final information regarding the stopping position of the train 100. In this embodiment, the comprehensive judgment is performed individually in each of the calculation unit 31 and the calculation unit 32.

[0037] 12, the calculation unit 31 makes a final determination as to whether the train 100 has stopped based on at least one of information A1, information A21, and information A22, and generates final information regarding the stopping position of the train 100. Then, when the calculation unit 31 determines that the train 100 has stopped, it determines whether the stopping position of the train 100 is within a predetermined range. When the calculation unit 31 determines that the stopping position of the train 100 is within the predetermined range, it transmits a vehicle fixed position stop signal SA1 to the higher-level device 40.

[0038] In parallel with the above operation of the calculation unit 31, the calculation unit 32 also makes a final determination as to whether or not the train 100 has stopped based on at least one of the information A1, the information A21, and the information A22, and generates final information regarding the stopping position of the train 100. Then, when the calculation unit 32 determines that the train 100 has stopped, it determines whether or not the stopping position of the train 100 is within a predetermined range. When the calculation unit 32 determines that the stopping position of the train 100 is within the predetermined range, it transmits a vehicle fixed position stop signal SA2 to the higher-level device 40. In this way, the two calculation units 31 and 32 output the vehicle fixed position stop signal in order to increase the certainty that the train 100 is stopped at the predetermined position when the platform doors are opened.

[0039] In one example, the calculation units 31 and 32 may make a final stop determination and generate information on the stop position using the information A1 based on the radar sensor as a main determination material during a time period when both the disparity data from the first stereo camera 21 and the disparity data from the second stereo camera 22 are unstable due to the effects of weather, season, and sunlight. The calculation units 31 and 32 may also make a final stop determination and generate information on the stop position based on the information A1 and the information A21 during a time period (first time period) when the disparity data from the second stereo camera 22 is unstable due to the effects of weather, season, and disturbance light such as sunlight. The calculation units 31 and 32 may also make a final stop determination and generate information on the stop position based on the information A1 and the information A22 during a time period (second time period) when the disparity data from the first stereo camera 21 is unstable due to the effects of weather, season, and disturbance light such as sunlight. Alternatively, in a railway station where the disparity data from the first stereo camera 21 and the second stereo camera 22 is always unstable due to the direction in which the platform 3 extends and surrounding structures, the calculation units 31 and 32 may always use the information A1 based on the radar sensor as the main criterion for making the final stop determination and generating the information on the stop position. In this way, which of the information A1, information A21, and information A22 the calculation units 31 and 32 use can be determined depending on various situations.

[0040] The host device 40 is, for example, a device that controls the opening and closing of platform doors. The host device 40 opens and closes the platform doors only when one or both of the vehicle fixed position stop signal SA1 from the calculation unit 31 and the vehicle fixed position stop signal SA2 from the calculation unit 32 indicate that the stopping position of the train 100 is within a predetermined range.

[0041] The effects obtained by the train stop detection device 1 of the present embodiment described above will be described. The train stop detection device 1 of the present embodiment includes stereo cameras (the first stereo camera 21 and the second stereo camera 22). Since the stereo cameras do not emit laser light, they are not easily affected by the surface color of the railcar 101 or the light reflectance of the surface of the railcar 101. Therefore, the above-mentioned drawbacks of distance measurement using laser light can be overcome. In addition, the stereo cameras may be affected by disturbance light such as sunlight, making the measurement unstable. Therefore, in the train stop detection device 1 of the present embodiment, the processing unit 30 determines whether the train 100 has stopped based on information from one or both of the two stereo cameras, i.e., the first stereo camera 21 and the second stereo camera 22, and generates information regarding the stopping position of the train 100. As a result, it is possible to accurately detect that the train 100 has stopped and the stopping position of the train 100 while suppressing the influence of disturbance light such as sunlight.

[0042] As in this embodiment, the installation height of the first stereo camera 21 relative to the platform 3 may be different from the installation height of the second stereo camera 22 relative to the platform 3. In that case, in order to capture the same imaging target part 130, the inclination angle α1 of the optical axis AX3 of the lens of the first stereo camera 21 and the inclination angle α2 of the optical axis AX4 of the lens of the second stereo camera 22 are different from each other, as shown in Fig. 11. This makes it possible to prevent the first stereo camera 21 and the second stereo camera 22 from being simultaneously affected by ambient light such as sunlight.

[0043] As in this embodiment, the processing unit 30 may determine whether the train 100 has stopped and generate information related to the stopping position of the train 100 based on the information A21 during a first time period, and may determine whether the train 100 has stopped and generate information related to the stopping position of the train 100 based on the information A22 during a second time period different from the first time period. In this case, it is possible to suitably determine whether the train 100 has stopped and measure the stopping position of the train 100 while avoiding the influence of external light (e.g., sunlight) that changes depending on the time period.

[0044] 9, at least one of an axis AX1 connecting the two cameras 211, 212 constituting the first stereo camera 21 and an axis AX2 connecting the two cameras 221, 222 constituting the second stereo camera 22 may be parallel to the platform 3. In this case, the installation work of the first stereo camera 21 and the second stereo camera 22 can be facilitated.

[0045] 10, at least one of the axis AX1 connecting the two cameras 211, 212 constituting the first stereo camera 21 and the axis AX2 connecting the two cameras 221, 222 constituting the second stereo camera 22 may be inclined with respect to the platform 3. In this case, the brightness difference between pixels in the horizontal direction increases, and the number of detected disparity data increases. Therefore, at least one of the information A21 and the information A22 can be generated with higher accuracy, and the accuracy of detecting that the train 100 has stopped and the stopping position of the train 100 can be further improved.

[0046] As in this embodiment, the imaged portion 130 may include a rearward portion 105a of the side surface 105 of the front railcar 101A, a frontward portion 107a of the side surface 107 of the rear railcar 101B, and a portion 111a of the side surface 111 of the gangway hood 110 of the two railcars 101A and 101B coupled together. In the stereo image, the difference between the distance to the side surfaces of the front and rear railcars and the distance to the side surface of the gangway hood is one of the most characteristic portions that can be used to determine the position of the train. Therefore, according to the train stop detection device 1 of this embodiment, it is possible to further improve the accuracy of detection of the stop of the train 100 and the stopping position of the train 100.

[0047] As in this embodiment, one or both of the first stereo camera 21 and the second stereo camera 22 may be installed to face diagonally downward. In this case, the influence of disturbance light such as sunlight can be further reduced, and the accuracy of detecting that the train 100 has stopped and the stopping position of the train 100 can be further improved.

[0048] As in the present embodiment, when it is determined that the train 100 has stopped, the processing unit 30 may determine whether or not the stopping position of the train 100 is within a predetermined range. In this case, for example, a higher-level device 40 that controls the opening and closing of platform doors can receive from the processing unit 30 vehicle fixed position stop signals SA1, SA2 relating to whether or not the stopping position of the train 100 is within a predetermined range, and determine whether or not the platform doors are opened or closed.

[0049] The train stop detection device according to the present disclosure is not limited to the above-mentioned embodiment, and various other modifications are possible. For example, in addition to the above-mentioned functions, the processing unit 30 may further have at least one of the following functions: a function for detecting abnormalities or failures in the distance measurement unit 10 and the processing unit 30; a function for displaying the state of the train stop detection device (for example, by lighting an LED); a function for setting parameters used in the overall judgment; and a function for recording a log of the judgment result and information of the distance measurement unit 10. In addition, in the above-mentioned embodiment, two stereo cameras, namely the first stereo camera 21 and the second stereo camera 22, are provided, but only one of the stereo cameras may be provided. In addition, in the above-mentioned embodiment, the image-captured portion 130 includes portions of two railcars 101A and 101B, but the image-captured portion may include portions of only one railcar 101, or three or more railcars 101. [Explanation of symbols]

[0050] 1...train stop detection device, 3...platform, 10...distance measurement unit, 11...first radar sensor, 11a...transmitter, 11b...mounting mechanism, 12...second radar sensor, 12a...transmitter, 12b...mounting mechanism, 21...first stereo camera, 22...second stereo camera, 30...processing unit, 31 to 33...calculation unit, 34...communication line, 40...higher-level device, 100...train, 101, 101A, 101B...railroad vehicle, 102...vehicle coupling unit, 103, 104...end surface, 103a, 104a...area, 105, 107...side surface, 105a, 1 07a...part, 106, 108...edge, 110...through canopy, 111...side, 111a...part, 121, 122...measurement target area, 130...image target area, 211, 212, 221, 222...camera, A1, A21, A22...information, AX1, AX2...axis, AX3, AX4...optical axis, D1, D2...parallax data, DA...synthetic data, H1, H2...virtual plane, Q...shooting range, RW...radio wave, S1, S2...ranging signal, SA1, SA2...vehicle fixed position stop signal, W1, W2...spacing, α1, α2...tilt angle, θ1, θ2...tilt angle.

Claims

1. A device that is installed on a platform of a railway station and detects when a train having a plurality of railroad cars has stopped and the stopping position of the train, a first stereo camera that captures an image of a predetermined portion of at least one of the railcars and outputs first parallax data; a second stereo camera configured to capture an image of the predetermined portion of at least one of the railcars and output second parallax data; a processing unit that determines whether or not the train has stopped based on one or both of first information regarding whether or not the train has stopped and a stopping position of the train, the first information being generated based on the first disparity data, and second information regarding whether or not the train has stopped and a stopping position of the train, the second information being generated based on the second disparity data, and that generates information regarding the stopping position of the train; A train stop detection device comprising:

2. 2. The train stop detection device according to claim 1, wherein an installation height of the first stereo camera relative to the platform and an installation height of the second stereo camera relative to the platform are different from each other.

3. The train stop detection device of claim 2, wherein the processing unit determines whether the train has stopped and generates information regarding the stopping position of the train based on the first information during a first time period, and determines whether the train has stopped and generates information regarding the stopping position of the train based on the second information during a second time period different from the first time period.

4. At least one of an axis line connecting the two cameras constituting the first stereo camera and an axis line connecting the two cameras constituting the second stereo camera is parallel to the platform. The train stop detection device according to any one of claims 1 to 3.

5. The train stop detection device according to any one of claims 1 to 3, wherein at least one of an axis connecting the two cameras constituting the first stereo camera and an axis connecting the two cameras constituting the second stereo camera is inclined with respect to the platform.

6. The predetermined portion is A part of a side surface of a front one of the two railcars coupled to each other, the side surface being closer to the rear of the front one of the two railcars; A part of a side surface of the rear one of the two railcars, the side surface being closer to the front; At least a part of a side of a gangway hood connecting the two railcars; The train stop detection device according to any one of claims 1 to 3, comprising:

7. The train stop detection device according to any one of claims 1 to 3, wherein one or both of the first stereo camera and the second stereo camera are installed so as to face diagonally downward.

8. The train stop detection device according to any one of claims 1 to 3, wherein the processing unit, when determining that the train has stopped, determines whether the stopping position of the train is within a predetermined range.

Images