JP6091294B2 - Train head position detection method and detection apparatus - Google Patents

Description

  The present invention relates to a detection method and a detection device for detecting the train head position of a train traveling on a track, and in particular, it is possible to accurately detect the front position of a traveling body even when there is a disturbance to the detection. It relates to the technology.

As is well known, a train that has entered the platform of a station stops at a preset target stop position on the platform, and then the train door is opened and closed for passengers to get on and off.
In recent years, on the Shinkansen, conventional lines, and subways, movable fences and platform doors have been installed on platforms as one of the safety measures aimed at preventing passengers from falling from the platform and accidental contact with trains. It is becoming.

  In such movable fences and platform doors, the door is provided in accordance with the position of the train door stopped at the target stop position, so that the train is reliably stopped at the target stop position and the platform door is opened and closed. Is required to determine whether the train is stopped within the target stop position or within an allowable range before and after the target stop position. At present, such a judgment must be relied upon visually (manually) by a station attendant or the like.

Therefore, the applicants of the present application have already developed a technique as disclosed in Patent Document 1.
Patent Document 1 discloses a distance from the distance sensor to the front of the train using a distance sensor that irradiates the front of the train during a stop operation while scanning the spot-shaped measurement light in a line along the left-right direction. And a train stop position detection method for detecting the stop state and stop position of the train based on the measured distance.

JP 2012-240519 A

By using the technique described in Patent Document 1 described above, the “train stop position of the train”, in other words, the “train start position” can be detected almost certainly at low cost.
However, since the technique of Patent Document 1 irradiates spot-like measurement light on the front surface of a train that is in a stop operation, if normal irradiation or reflection of measurement light is not realized, There is a possibility that the head position is erroneously detected.

For example, when a train traveling on the ground is considered, a situation in which normal irradiation or reflection of measurement light cannot be realized easily due to rain or snow. That is, when it rains or snows, the measurement light is blocked by raindrops or snow particles, and the distance to the front of the train may not be detected accurately.
In addition, obstacles such as garbage thrown away at the platform of the station and obstacles equivalent to the train width enter the track where the train travels, and the distance to these obstacles is the distance to the head of the train There is also a possibility of erroneous determination. The technique of Patent Document 1 does not correspond to the above-described situation, and it is difficult to detect the accurate start position of the train only with the technique of Patent Document 1.

  The present invention has been made in view of the above problems, and even when there is a disturbance to detection such as rain, snow, etc., the front of the train is accurately extracted, and the head position of the train traveling on the track is determined. Provide detection technology for reliable detection.

In order to achieve the above object, the present invention takes the following technical means.
That is, the detection method of the train head position according to the present invention uses a distance sensor that irradiates the front surface of the train in a stop operation while scanning the spot-shaped measurement light in a line along the left-right direction. In the train head position detection method for measuring the distance from the distance sensor to the front of the train and detecting the train head position based on the measured distance, it is raining on the distance data obtained from the distance sensor. The false detection avoidance process by the rain is detected and the head position of the train is detected. The false detection avoidance process by the rain is based on the distance data obtained from the distance sensor based on the continuity of the scanning of the measurement light. with grouped into, select a group number is largest distance data, wherein determining the head position of the train based on distance data belonging to the selected group To.

In addition, the method for detecting the train head position according to the present invention uses a distance sensor that irradiates the front surface of a train in a stop operation while scanning a spot-shaped measurement light in a line along the left-right direction. In the train head position detection method for measuring the distance from the distance sensor to the front of the train and detecting the train head position based on the measured distance, it is raining on the distance data obtained from the distance sensor. The false detection avoidance process by the rain is detected and the head position of the train is detected. The false detection avoidance process by the rain is based on the distance data obtained from the distance sensor based on the continuity of the scanning of the measurement light. And select the group with the largest number of distance data and create a histogram using the distance data belonging to the selected group. Select the class that contains a predetermined statistical value in grams, and determines the head position of the train based on belonging distance data to the selected class.

Preferably, the distance data obtained from the distance sensor is subjected to the false detection avoidance process due to the rain, and then the false detection avoidance process due to the obstacle is performed to detect the head position of the train. Yes, the false detection avoidance process by the obstacle sets an area including the top position of the train obtained by the false detection avoidance process by the rain, and the number of distance data existing in the area is a predetermined number. When it exists, it is good to determine that the head position of the train is correct.

Preferably, after applying the false detection avoidance process due to the rain to the distance data obtained from the distance sensor, the width is substantially the same as the width of the train after the false detection avoidance process due to the obstacle. Or avoiding erroneous detection due to an obstacle corresponding to the train width which is an obstacle having a length, and detecting the leading position of the train, and avoiding erroneous detection due to the obstacle corresponding to the train width is The entry area is set on both sides in the longitudinal direction of the detection area, which is a search area set as a vertically long area including the center of the train, the comparison area is set in the center, and the train head position is It is preferable to determine that the start position of the train is correct when the start position of the train continuously changes with time so as to enter the entry area and then move to the comparison area.

  In addition, the train head position detection device according to the present invention irradiates the front surface of the stopping train while irradiating a spot-shaped measurement light in a line along the left-right direction, and from the distance sensor to the train A distance sensor that measures the distance to the front of the train, and a detection unit that detects the start position of the train by the above-described method of detecting the train stop position.

  According to the train head position detection technology according to the present invention, even when there is a disturbance to the detection, such as rain, snow, etc., the front surface of the train is accurately extracted, and the head position of the train traveling on the track is ensured. Can be detected.

It is a perspective view which shows the detection apparatus of a train head position. (A) is the figure which showed planarly the positional relationship of the distance center installed on the station platform, a train, and the coordinate system for a detection, (b) is for searching a train head position. The search area is shown. (A) is a figure which shows the data of the head shape of the train obtained at the time of rain, (b) is the elements on larger scale of (a). It is a schematic diagram for demonstrating the process which avoids the misdetection at the time of rain (the 1). It is a schematic diagram for demonstrating the process which avoids the misdetection at the time of rain (the 2). It is a schematic diagram for demonstrating the process which avoids the erroneous detection by an obstruction. It is a schematic diagram for demonstrating the process which avoids the erroneous detection by the obstruction equivalent to a train width. It is a flowchart which shows the process which detects a train head position.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a train head position detection method and a detection apparatus according to the present invention will be described with reference to the drawings.
[Basic technology for detecting the beginning of a train]
The train head position detection device 1 according to the present invention is installed at a platform 2 of a station such as a Shinkansen, a conventional line, a new transportation system, and the like. The stop position is detected.

The train 3 used in the following description includes various traveling bodies that travel on the track 4, such as trains, monorails, and streetcars. In the following description, the right-left direction facing the train traveling direction is the right-left direction in the description.
As shown in FIG. 1, the detection device 1 of the present embodiment irradiates the measurement light 5 on the front surface of the train 3 that is in a stop operation, and measures the distance to the front surface of the train 3. And a detection unit 7 that detects the distance to the front surface of the train 3 based on the distance measured by the distance sensor 6. Note that “stopping operation” means that the train 3 is being decelerated manually or automatically to stop at the stop target position.

The distance sensor 6 is a non-contact distance meter that uses spot laser light as the measurement light 5 and is called a laser distance meter. This distance sensor 6 uses the stop target position provided in advance as the stop target of the train 3 on the platform 2 (the platform 2 for raising and lowering the train installed in the station) as a reference, and further in the train traveling direction than the stop target position. Deployed forward.
As a specific installation location of the distance sensor 6, it may be installed on the home 2, or may be installed in a vacant space under the platform 2. The distance sensor 6 is installed at a position that can irradiate from the front of the train 3 and obliquely in the left-right direction.

  The distance sensor 6 irradiates the measurement light 5 toward the front surface of the train 3 so as to scan while reciprocating on a straight line along the left-right direction of the front surface of the train 3 (so as to form a one-dimensional line scan). ing. The distance sensor 6 measures the distance from the distance sensor 6 to the front surface of the train 3 by receiving the reflected light of the irradiated measurement light 5. The measurement light 5 is emitted from the distance sensor 6 at a constant period, and the distance is measured every time the irradiation is performed.

On the other hand, the detection unit 7 connected to the distance sensor 6 eliminates erroneously detected distance data based on a plurality of distance data measured by the distance sensor 6 regarding the “distance sensor 6 to the distance from the front of the train 3”. Above, it is comprised so that the distance to the position of the forefront edge part of the train 3 may be calculated | required. Specifically, the detection unit 74 is configured by a personal computer or the like.
Next, signal processing performed by the detection unit 7, specifically, a method for detecting a train stop position according to the present invention will be described.

First, consider a case where the train 3 enters the home 2 and gradually decreases in speed to approach the stop target position. At that time, the measurement light 5 is emitted from the distance sensor 6 provided at a position 10 m ahead of the traveling direction of the train 3 with respect to the stop target position, and is irradiated on the front surface of the train 3.
At this time, the distance sensor 6 measures the distance to the front surface of the train 3 and the irradiation angle of the measuring light 5 for each irradiation of the measuring light 5. The measurement result obtained in this way is data in polar coordinates indicated by an angle and a distance, and it is difficult to understand the distance to the train 3 as it is. Therefore, in the detection method of the present invention, the measurement result (polar coordinate data) measured by the distance sensor 6 is converted into orthogonal coordinate data.

  Specifically, as shown in FIG. 2A, the position information indicated by the distance measured by the distance sensor 6 and the irradiation angle at that time is converted by (X, Y) = (Lconθ, Lsinθ). . As shown in FIG. 2 (a), the XY coordinates are set such that the Y axis is set in the direction along the platform 2, in other words, along the direction in which the train 3 enters, the width direction of the train 3, In other words, the X axis is set in a direction orthogonal to the track 4.

The distance data obtained in this way is plotted in the XY coordinate system as shown in FIG. In this plot, the point having the smallest value along the Y-axis is a portion corresponding to the front end portion of the train 3, and the Y value of this portion indicates the train head position.
FIG. 3B shows ten pieces of distance data corresponding to only a part of FIG.
[About false positives]
By the way, as explained in detail in “Problems to be Solved by the Invention”, the above-described train stop position detection device 1 irradiates the measurement light 5 on the front surface of the train 3 during the stop operation. Therefore, if normal irradiation and reflection of the measurement light 5 are not realized, there is a possibility that the leading position of the train 3 is erroneously detected.

  For example, when the rain or snow falls, the measurement light 5 may be blocked by raindrops or snow particles, and the distance to the front of the train 3 may not be accurately detected. Further, there is a possibility that an obstacle such as a garbage bag (a relatively small obstacle) enters the rail on which the train 3 travels and erroneously determines that the distance to the obstacle is the distance to the front of the train 3. There is also. Conversely, an obstacle corresponding to the train width enters the rail on which the train 3 travels, and the distance to the obstacle corresponding to the train width may be erroneously determined as the distance to the front surface of the train 3.

Therefore, the detection apparatus 1 of the present invention has the following processing for avoiding false detection. These processes are performed in the detection unit. In the following description, rainfall and snowfall are collectively referred to as “rainfall”, and raindrops and snow particles that block the measurement light 5 are collectively referred to as “raindrop”.
[Prevention of false detection due to rain]
First, “a false detection avoidance process due to rainfall” performed in the detection unit will be described.

In the process of avoiding erroneous detection due to rain, the following processing is performed on the measurement point group at the train head obtained from the distance sensor 6, and as a result, the accurate train 3 start position is determined.
First, as shown in FIG. 2 (b), at the head of the train, the head position is likely to cause a detection error such as a handrail, a headlight, a destination display board, a decorative board, and a connecting frame at a part off the train head. In many cases, it has a structure that does not regulate Therefore, a portion excluding the region having these structures is set as a search region G, and attention is paid to scan data of the measurement light 5 in this region (distance data obtained by scanning the measurement light 5). The search area G is a vertically long area including the center of the train, and is a center in the width direction of the track 4 on which the train 3 travels, as shown in FIG. 2B, and has a predetermined length along the track 4. A rectangular area is set. This search area G is set on the front side of the distance sensor 6.

In the train head part, the part off the train head part often has a structure such as a handrail, a headlight, a destination display board, a decorative board, a connecting frame, etc. that is likely to cause a detection error and does not define the head position. Therefore, by setting the search region G in a portion excluding the region having these structures, it is possible to search the head position with high reliability.
FIG. 3A shows scan data (distance data) obtained in the search area G, and an enlarged portion thereof (part corresponding to the head position of the train 3) is shown in FIG. 3B. .

  FIG. 3B shows a plurality of distance data (10 points of scan data) in the search area G. Among the scan data in FIG. 3B, the data indicated by A indicates the frontmost part of the front of the train 3. On the other hand, the data indicated by C is data reflected by the measurement light 5 from the distance sensor 6 hitting raindrops or the like, and does not indicate the distance to the front surface of the train 3.

Only data indicating the distance to the front surface of the train 3 is extracted from such distance data. For this purpose, attention is paid to the continuity of the scan data of the measurement light 5.
That is, as shown in FIG. 4, it is assumed that the scan lines of the measurement light 5 are No. 1 to No. 12. Among them, for No. 1 to No. 8, the distance data (circles in FIG. 4) can be obtained in the search area G by increasing the number of scans by one. In the subsequent scan lines No. 9 and No. 10, data exists outside the search area G, and distance data can be newly obtained in the search area G at No. 11 and No. 12.

In such a case, there is a discontinuity in the scan angle between the distance data of No. 1 to No. 8 and the distance data of No. 11 and No. 12. When there is a discontinuity in this way, the distance data before and after the discontinuity is grouped as belonging to another group. That is, the distance data No. 1 to No. 9 is set as the first group (D1 in FIG. 4), and the distance data No. 11 and No. 12 is set as the second group (D2 in FIG. 4). In this way, the distance data is clustered using the discontinuity of the scan angle.

  Since the distance data belonging to the first group obtained by this processing has the largest number of distance data compared to other groups (number of data: 8), the distance data belonging to the first group is The distance data corresponding to the front surface of the train 3 is estimated, and the distance data belonging to the second group is estimated to be distance data corresponding to raindrops, that is, disturbance. Therefore, in the subsequent process, the distance data belonging to the second group is excluded and the process proceeds.

As described above, distance data is grouped based on the continuity of the scan angle, and the group with the most measurement points is determined as the most reliable measurement point group. Disturbances such as distance data corresponding to can be reliably eliminated.
However, when examining FIG. 4, the distance data obtained by scanning No. 4 in the first group has a value slightly different from other distance data. The distance data No4 corresponds to the data B in FIG.

As described above, the reason why the distance data of No4 is different from the other data is considered that the distance data of No4 scanned “raindrops that existed in front of the leading portion of the train 3”.
Therefore, in the present invention, processing for eliminating such disturbance is also performed.
That is, as shown in FIG. 5, paying attention to the Y coordinate value (distance from the distance sensor 6 to the train 3 along the track 4) of the distance data belonging to the first group, a histogram of the Y coordinate value is created. Thereafter, the class that is the mode (mode value) in the created histogram is selected. Thereafter, attention is paid only to the distance data belonging to the selected class range, and attention is focused on the data having the smallest Y coordinate value. This smallest Y coordinate value is defined as “distance from distance sensor 6 to train 3 front surface”, that is, “train start position”. The distance data based on raindrops existing in front of the head portion of the train 3 is considered to exist in a single shot, and the distance data based on raindrops does not become the mode value. Therefore, by performing this process, it is possible to reliably eliminate disturbance due to raindrops.

In this process, in addition to the mode value, other statistical information (predetermined statistical value) such as a median value and an average value may be adopted to eliminate disturbance due to raindrops.
In summary, measurement points such as raindrops and snowdrops often appear as isolated points that are spatially and temporally discontinuous. Therefore, reliability due to disturbances such as raindrops by continuously performing distance data clustering processing and distance data mode processing (mode processing) by avoiding false detection due to rain Can be determined and removed.

In addition, the shape profile of the front surface of the train 3 can be obtained by connecting the distance data belonging to the most reliable measurement point.
[Avoidance of false detection due to obstacles]
Next, a description will be given of “a false detection avoidance process due to an obstacle” performed in the detection unit.
By performing the “prevention process of erroneous detection due to rain” described above, the head position of the train 3 can be reliably detected under normal circumstances.

  However, in the station platform 2 in which the detection apparatus 1 of the present invention is installed, for example, some trash (a relatively small obstacle such as a plastic bag) from a trash box present on the platform 2 on a windy day. May even scatter. When the dust that floats in this way enters the track 4 on which the train 3 travels and exists between the distance sensor 6 and the train 3, the distance to the obstacle is the distance to the front of the train 3. May be misjudged.

In order to avoid erroneous detection under such circumstances, “error detection avoidance processing due to obstacles” is executed in the detection unit. The details of avoiding erroneous detection due to obstacles will be described below.
First, it is assumed that distance data (F in FIG. 5) indicating the head position of the train 3 is obtained by the above-described erroneous detection avoidance process due to rain.
Thereafter, as shown in FIG. 6, a rectangular neighborhood H is set that includes the leading position F of the train 3 at the right end and extends to the left. This neighborhood area H has a predetermined range determined from the shape of the train 3 in the Y direction (train traveling direction), the width to the vehicle limit on both sides in the train width direction in the X direction, or the train width. The direction shall have a width from the rail center to the vehicle limit.

  Next, the number of distance data existing in the neighborhood region H is counted. When the count number is greater than or equal to the predetermined number, it becomes clear that the object reflecting the measurement light 5 has a sufficient size, that is, the front surface of the train 3. In other words, it becomes clear that the distance data F considered to be the head of the train 3 is not obtained by reflected light from a small object like a floating plastic bag.

Note that, as a threshold for the number of distance data in the neighborhood region H, the measurement points that exist in the neighborhood region H with respect to the defined neighborhood region H on the basis of how many times the position detection sensor scans are set. If there is a predetermined ratio or more, it may be determined that there are a predetermined number or more.
By performing the avoidance process of the false detection due to the obstacle described above, the false detection due to an object (obstacle) that is smaller than the head of the train 3, such as when an obstacle such as a garbage bag enters the rail, etc. It can be surely prevented. By setting the neighborhood area H in the false detection avoidance process due to this obstacle to the width of the vehicle limit on both sides of the train 3 in the X direction, erroneous detection due to an obstacle smaller than the size of the head of the train is surely eliminated. It becomes possible to do. On the other hand, by setting the vicinity region H to the width from the rail center to the vehicle limit in the X direction, it is possible to reliably eliminate erroneous detection due to the effect of a decorative board or the like arranged at the front of the train 3.
[Avoidance of false detection due to obstacles equivalent to train width]
Finally, “a false detection avoidance process using an obstacle corresponding to the train width” performed in the detection unit 7 will be described.

  As described above, although very rare, an obstacle corresponding to the train width may enter the track 4 from the platform 2. In that case, an abnormal value is output from the distance sensor 6, and the distance calculated from the abnormal value is considered to indicate a discontinuous Y coordinate value. Therefore, in the avoidance process of erroneous detection due to an obstacle corresponding to the train width, it is detected whether the distance data continuously changes with time, in other words, whether the train 3 is moving, and avoids erroneous detection. I am doing so. The obstacle corresponding to the train width is a large obstacle having a width or length substantially the same as the width of the train.

First, attention is paid to the “start position F of the train 3” obtained through the avoidance process of erroneous detection due to rainfall and the avoidance process of erroneous detection due to obstacles.
Then, it is confirmed whether or not the leading position F of the train 3 continuously moves with time along the Y axis. If the head position F of the train 3 suddenly appears (discontinuously appears or disappears), it is determined that an abnormal value is output from the distance sensor 6 due to an obstacle equivalent to the train width, etc. We will recognize the state.

  Specifically, as shown in FIG. 7, “search area G” set as a vertically long area including the center of train 3 is considered again as “detection area”. An approach area is set on both sides in the longitudinal direction of the detection area, and a comparison area is set in the center. When the detection apparatus 1 detects the head of the train normally, the train 3 is in a stop operation, so that the train head position F moves so as to move sequentially along the Y axis. Therefore, the train head position F first enters the entry area of the detection area, and then moves to the comparison area that compares the past head position with the current head position. This situation is shown in FIGS. 7A and 7B, and is considered to be a normal movement of the train head position F. FIG.

In this way, by observing the continuity along the time axis of the head position F, even if there is an obstacle equivalent to the train width that cannot be avoided by the “error detection avoidance process due to an obstacle”, the erroneous detection can be ensured. It can be avoided. In addition, it is possible to reliably avoid erroneous detection accompanying output of abnormal distance data due to a failure of the distance sensor 6 or the like.
[Procedure for avoiding false positives]
The false detection avoidance process described above is performed in the following order in the detection unit.

That is, as shown in FIG. 8, first, in step 1 (S1, hereinafter referred to as such), distance data corresponding to “search area G” set as a vertically long area including the train center is extracted. . If there is no distance data as a result of extraction, it is assumed that the train 3 does not exist (No in S2).
If there is distance data (Yes in S2), "a false detection avoidance process due to rain" is performed. The false detection avoidance process due to rainfall includes a process S3 for extracting a measurement point within the head detection range and a process S4 for extracting the maximum cluster. At the same time, the misdetection avoidance process due to the rain includes the process S5 for creating a histogram with Y coordinate values, the process S6 for extracting the mode value group, and the minimum Y coordinate point in the mode value group 3 The process S7 is extracted as the head position. Note that the order of executing “S3, S4” and “S5 to S7” may be reversed. That is, “S3, S4” may be executed after performing “S5 to S7”.

Thereafter, “a false detection avoidance process due to an obstacle” is performed (S8, S9). Furthermore, "a false detection avoidance process due to an obstacle corresponding to the train width" is performed (S10, S11). Note that the order of executing “S8, S9” and “S10, S11” may be reversed. That is, “S8, S9” may be executed after “S10, S11”.
By performing the above processing, the front position of the traveling body is accurately extracted even when there is a disturbance to the detection, such as rain or snow, and the leading position of the train 3 traveling on the track 4 is reliably detected. (S12).

  By the way, it should be thought that embodiment disclosed this time is an illustration and restrictive at no points. In particular, in the embodiment disclosed this time, matters that are not explicitly disclosed, for example, operating conditions and operating conditions, various parameters, dimensions, weights, volumes, and the like of a component deviate from a range that a person skilled in the art normally performs. Instead, values that can be easily assumed by those skilled in the art are employed.

DESCRIPTION OF SYMBOLS 1 Detection apparatus 2 Home 3 Train 4 Track 5 Measurement light 6 Distance sensor 7 Detection part

Claims (5)

Measure the distance from the distance sensor to the front of the train by using a distance sensor that irradiates the front of the train while it is stopping while scanning the spot-shaped measuring light in a line along the left-right direction. In the detection method of the train head position that detects the train head position based on the determined distance,
For the distance data obtained from the distance sensor, a process for avoiding erroneous detection due to rain, and detecting the start position of the train ,
The process of avoiding erroneous detection due to rain is to group the distance data obtained from the distance sensor based on the continuity of the scan of the measurement light, and select the group with the largest number of distance data,
A train head position detection method, wherein a train head position is determined based on distance data belonging to a selected group . Measure the distance from the distance sensor to the front of the train by using a distance sensor that irradiates the front of the train while it is stopping while scanning the spot-shaped measuring light in a line along the left-right direction. In the detection method of the train head position that detects the train head position based on the determined distance,
For the distance data obtained from the distance sensor, a process for avoiding erroneous detection due to rain, and detecting the start position of the train,
The process of avoiding erroneous detection due to rain is a method of grouping the distance data obtained from the distance sensor based on the continuity of the scan of the measurement light, and selecting the group having the largest number of distance data,
Create a histogram using the distance data belonging to the selected group,
In the created histogram, select the class that contains the given statistical value,
A train head position detection method, wherein a train head position is determined based on distance data belonging to a selected class . With respect to the distance data obtained from the distance sensor, after performing the avoidance processing erroneous detection due to the rain, it performs avoidance processing erroneous detection by the obstacle, which detects the head position of the train,
The avoidance process of false detection due to the obstacle sets an area including the start position of the train obtained by the avoidance process of false detection due to rain, and the number of distance data existing in the area is greater than or equal to a predetermined number. The train head position detection method according to claim 1 or 2, wherein the train head position is determined to be correct when the train is started . With respect to the distance data obtained from the distance sensor, after applying the avoidance process of erroneous detection due to the rain, after avoiding the process of erroneous detection by the obstacle, the width substantially the same width or the length of the train is performed avoiding process of erroneous detection by the train width corresponding obstacle is the obstacle with a shall detect the head position of the train,
The avoidance process of false detection by an obstacle equivalent to the train width is
Set the approach area on both sides in the longitudinal direction of the detection area that is the search area set as a vertically long area including the center of the train, set the comparison area in the center, the train head position is first of the detection area It is determined that the train start position is correct when the train start position continuously changes with time so as to enter the approach area and then move to the comparison area. The method for detecting a train head position according to claim 3 . A distance sensor that measures the distance from the distance sensor to the front surface of the train by irradiating the front surface of the train being stopped while scanning in a line with a spot-shaped measurement light along the left-right direction;
The detection part which detects the head position of a train by the detection method of the train stop position described in any one of Claims 1-4 ,
A train head position detecting device.