Data processing apparatus, data processing method, and program

Abstract

To provide a technique capable of realizing a sensor for determining whether or not a moving body is stopped and a sensor for determining whether or not a detection object exists in a detection area by the same sensor.SOLUTION: There is provided a data processing apparatus including a first determination unit configured to perform determination processing of determining, based on first ranging data of a detection area obtained by a LiDAR, whether or not a detection target exists in the detection area, a second determination unit configured to determine, based on second ranging data obtained by the LiDAR, whether or not a moving body different from the detection target is stopped, and a determination control unit configured to start the determination processing when it is determined that the moving body is stopped.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a data processing device, a data processing method, and a program. [Background technology]

[0002] In recent years, a technology has been known that determines whether a moving object is stationary. An example of a moving object is a train. Also, a technology has been known that determines whether a detection target is present within a detection area. An example of a detection target is a person. Furthermore, a technology has been known that determines whether a detection target is present within a detection area based on a determination result obtained by determining whether a moving object is stationary. For example, Patent Document 1 discloses a technology that changes a detection area depending on whether a moving object is stationary.

[0003] Generally, the sensor for determining whether a moving object is stationary is different from the sensor for determining whether a detection target exists within a detection area. For example, in the technology described in Patent Document 1, it is determined whether a moving object is stationary based on the detection result by an infrared sensor, and it is determined whether an object exists within a detection area based on the detection result by a scanner. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-82088 Summary of the Invention [Problem to be solved by the invention]

[0005] However, if the sensor for determining whether the moving object is stationary and the sensor for determining whether the detection target is present within the detection area are different sensors, two sensors are required, which not only increases the probability of sensor failure but also increases the operating costs of the sensors.

[0006] Furthermore, if the sensor for determining whether the moving body is stopped and the sensor for determining whether the detection target is present within the detection area are different sensors, there may be a difference in the timing at which the detection results from the two sensors reach the determination device, which may result in a delay in the determination process based on the detection results from the two sensors.

[0007] Therefore, the present invention has been made in consideration of the above problems, and an object of the present invention is to provide a technology that can realize, using the same sensor, a sensor for determining whether a moving body is stopped and a sensor for determining whether a detection target is present within a detection area. [Means for solving the problem]

[0008] In order to solve the above problem, according to one aspect of the present invention, a data processing device is provided, comprising: a first judgment unit that performs a judgment process to determine whether or not a detection target is present within a detection area based on first ranging data of the detection area obtained by LiDAR; a second judgment unit that determines whether or not a moving object other than the detection target is stopped based on second ranging data obtained by the LiDAR; and a judgment control unit that starts the judgment process when it is determined that the moving object is stopped.

[0009] The second determination unit may determine whether the moving body is moving based on third ranging data obtained by the LiDAR after the second ranging data is obtained by the LiDAR, and the determination control unit may stop the determination process when it is determined that the moving body is moving.

[0010] The data processing device may include a third judgment unit that judges whether or not a first transition has occurred from a state in which the moving body is present within a predetermined range to a state in which the moving body is not present within the predetermined range after the judgment process is stopped, and the judgment control unit may resume the judgment process when it is judged that the first transition has occurred.

[0011] The data processing device may include a third judgment unit that judges whether a second transition has occurred from a state in which the moving body is not within a specified range to a state in which the moving body is present within the specified range before the judgment process is started, and the judgment control unit may stop the judgment process when it is judged that the second transition has occurred.

[0012] The specified range may include a range from the front position of the moving body when the front of the moving body reaches one end of a station platform to the rear end position of the moving body when the rear end of the moving body reaches the other end of the platform.

[0013] The first determination section may perform the determination process based on a difference between the first distance measurement data and data for determination process stored in advance.

[0014] The detection area may include a time judgment area, the first ranging data may include current ranging data of the time judgment area, and the data for judgment processing may include past ranging data of the time judgment area, and the first judgment unit may identify the difference between the current ranging data of the time judgment area and the past ranging data of the time judgment area as an object within the time judgment area, and may judge whether the detection target is present within the detection area based on whether the object's stay time within the time judgment area exceeds a threshold.

[0015] The detection area may include a size determination area, the first ranging data may include current ranging data of the size determination area, and the data for determination processing may include past ranging data of the size determination area, and the first determination unit may identify the difference between the current ranging data of the size determination area and the past ranging data of the size determination area as an object within the size determination area, and determine whether the detection target exists within the detection area based on whether the object exceeds a predetermined size.

[0016] The size determination area may be an area that includes a position higher than the floor surface of a platform of a station where the moving object stops.

[0017] The measurement range of the LiDAR may include an upper portion of the moving object.

[0018] The detection area may include an area between a station platform and a mobile object stopping at the station.

[0019] In addition, according to another aspect of the present invention, in order to solve the above problem, a data processing method executed by a computer is provided, which includes performing a determination process to determine whether or not a detection target is present within a detection area based on first ranging data of the detection area obtained by LiDAR, determining whether or not a moving object other than the detection target is stopped based on second ranging data obtained by the LiDAR, and starting the determination process when it is determined that the moving object is stopped.

[0020] In addition, according to another aspect of the present invention, in order to solve the above problem, a program is provided that causes a computer to function as a first judgment unit that performs judgment processing to determine whether or not a detection target is present within a detection area based on first ranging data of the detection area obtained by LiDAR, a second judgment unit that determines whether or not a moving object other than the detection target is stopped based on second ranging data obtained by the LiDAR, and a judgment control unit that starts the judgment processing when it is determined that the moving object is stopped. [Effects of the Invention]

[0021] As described above, the present invention provides a technology that enables a single sensor to be used as both a sensor for determining whether a moving body is stopped and a sensor for determining whether a detection target is present within a detection area. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a block diagram illustrating an example of the configuration of a data processing system according to an embodiment of the present invention. [Figure 2] 1 is a block diagram showing an example of a functional configuration of a data processing device 10 according to an embodiment of the present invention. [Figure 3] FIG. 10 is a diagram showing a situation A1 around a platform H1 of a station at the time when the state of the occupied section changes from an unoccupied state to an occupied state. [Figure 4]FIG. 1 is a diagram showing a situation A2 around a station platform H1 at the time when a train T1 stops at the station. [Figure 5] FIG. 1 is a diagram showing a situation A3 around a station platform H1 at the time when a train T1 starts moving at the station. [Figure 6] FIG. 10 is a diagram showing a situation A4 around a platform H1 of a station at the time when the state of an occupied section C1 changes from an occupied state to an unoccupied state. [Figure 7] FIG. 10 is a diagram illustrating an example of a change in difference score over time. [Figure 8] This is a diagram summarizing the relationship between the situation, the fall detection process, and the state of train T1. [Figure 9] FIG. 10 is a diagram showing an example of a non-occupied train detection area that is set when the state of an occupied train section C1 is a non-occupied train state. [Figure 10] FIG. 10 is a diagram showing an example of an on-rail detection area that is set when the state of the on-rail section C1 is an on-rail state. [Figure 11] 1 is a flowchart showing an example of processing executed by the data processing system 1 according to the embodiment of the present invention. [Figure 12] 1 is a diagram showing a hardware configuration of an information processing device 900 as an example of a data processing device 10 according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant explanations will be omitted.

[0024] <1. Details of the embodiment> Next, details of the embodiment of the present invention will be described.

[0025] [1-1. Example of data processing system configuration] First, an example of the functional configuration of a data processing system according to an embodiment of the present invention will be described. Fig. 1 is a block diagram showing an example of the configuration of a data processing system according to an embodiment of the present invention. As shown in Fig. 1, the data processing system 1 according to an embodiment of the present invention includes a data processing device 10, a distance measuring device 20, a track signal receiving device 30, and an emergency light device 40. The data processing device 10, the distance measuring device 20, the track signal receiving device 30, and the emergency light device 40 may be connected via a network.

[0026] (Data processing device 10) 2 is a block diagram showing an example of the functional configuration of a data processing device 10 according to an embodiment of the present invention. The data processing device 10 can be realized by a computer. As shown in FIG. 2, the data processing device 10 includes a control unit 110 and a storage unit 190.

[0027] Control unit 110 includes a processor such as a CPU (Central Processing Unit), and its functions can be realized by the CPU expanding a program stored in a non-volatile storage device into RAM (Random Access Memory) and executing it. In this case, a computer-readable recording medium on which the program is recorded can also be provided. Alternatively, control unit 110 can be configured with dedicated hardware or a combination of multiple pieces of hardware.

[0028] The control unit 110 includes a rail-occupied / rail-non-occupied determination unit 120, a distance measurement data acquisition unit 130, a movement / stop determination unit 140, a determination control unit 150, a fall detection unit 160, and a notification control unit 170. Details of these components included in the control unit 110 will be described later.

[0029] The storage unit 190 is a storage device capable of storing programs and data for operating the control unit 110. The storage unit 190 can also temporarily store various data required in the course of operation of the control unit 110. For example, the storage device may be a non-volatile storage device.

[0030] (Distance measuring device 20) The distance measuring device 20 is a distance measuring sensor that obtains distance measurement data within a measurement range. The distance measuring device 20 then outputs the distance measurement data to the data processing device 10. More specifically, the distance measuring device 20 obtains the three-dimensional coordinates of an object within the measurement range (the distance from the distance measuring device 20 to the object for each two-dimensional coordinate) as distance measurement data. The distance measurement data includes the distance from the distance measuring device 20 to the object for each two-dimensional coordinate as a set of points (hereinafter also referred to as a "point cloud"). Therefore, the distance measurement data may correspond to point cloud data. An object existing in real space can be detected three-dimensionally from the point cloud.

[0031] For example, the distance measuring device 20 may be a LiDAR (Laser Imaging Detection and Ranging) that emits laser light, detects reflected light of the laser light, and measures distance based on information about the reflected light. LiDAR is also referred to as a laser sensor, and repeatedly scans a laser light two-dimensionally from the start point to the end point to continuously obtain scanning results (hereinafter also referred to as "frames").

[0032] However, various sensors other than LiDAR may be used as the distance measuring device 20. For example, a millimeter wave radar that uses millimeter waves instead of laser light may be used as the distance measuring device 20. Alternatively, a sonar that uses sound waves instead of laser light may be used as the distance measuring device 20.

[0033] The ranging device 20 is installed at a position where it can obtain ranging data of the detection area for determining whether or not a detection target exists. In the embodiment of the present invention, it is mainly assumed that the detection target is a person, the moving object is a train, and the detection area is set to include at least the area between a station platform and the moving object stopped at the station. It is also mainly assumed that it is determined whether or not a detection target exists in the detection area based on the ranging data of the detection area obtained by the ranging device 20.

[0034] This allows a person falling from the station platform to be detected, and measures can be taken to prevent an accident in which a person comes into contact with a train. However, the location where the distance measuring device 20 is installed may be changed depending on the location of the detection area, etc. Examples of locations where the distance measuring device 20 may be installed will be described in detail later.

[0035] A person is an example of a detection target. Therefore, objects other than a person can also be detection targets. For example, animals or inanimate objects other than a person (e.g., robots) can also be detection targets. Furthermore, a train is an example of a moving object. Therefore, objects other than trains can also be moving objects, and various objects that may come into contact with people can be moving objects. For example, vehicles other than trains (e.g., buses, automobiles, etc.) or ships can be moving objects. Note that a train may be made up of multiple cars coupled together, or it may be a single car.

[0036] (Train signal receiving device 30) When a train is present within a predetermined range, the train presence signal receiving device 30 receives a signal indicating that a train is present within the predetermined range.

[0037] In the following description, the specified range will also be referred to as the "train occupied section." The state in which a train is present in a train occupied section will also be referred to as the "train occupied state," and the state in which a train is not present in a train occupied section will also be referred to as the "train not occupied state." Furthermore, a signal indicating that a train is present in a specified range will also be referred to as the "train occupied signal." Information corresponding to whether a train occupied section is in the train occupied state or the train not occupied state will also be simply referred to as the "state of the train occupied section."

[0038] Figure 3 is a diagram showing the situation A1 around platform H1 of the station at the time when the state of the occupied section changes from an unoccupied state to an occupied state. As shown in Figure 3, the occupied section C1 may include the range from the front position of train T1 when the front of train T1 arrives at one end E1 (Figure 3) of platform H1 of the station to the rear end position of train T1 when the rear of train T1 arrives at the other end E2 (Figure 3) of platform H1 of the station. At this time, the track occupation signal receiving device 30 can receive the signal when train T1 is present on the tracks of the station.

[0039] The track presence signal receiving device 30 determines whether or not it is receiving a track presence signal at a predetermined reception determination period. If it determines that it is receiving a track presence signal, it outputs the track presence signal to the data processing device 10. When the track presence signal is input to the data processing device 10, the data processing device 10 determines that the state of the track presence section C1 is a track presence state. An example of a method by which the track presence detection device N1 transmits a track presence signal will be described in detail later.

[0040] On the other hand, when the track presence signal receiving device 30 determines that it has not received a track presence signal, it outputs a non-track presence signal to the data processing device 10. When the non-track presence signal is input to the data processing device 10, the data processing device 10 determines that the state of the track presence section C1 is a non-track presence state.

[0041] Alternatively, it may be assumed that the track presence detection device N1 is capable of transmitting a non-track presence signal. In such a case, the track presence signal receiving device 30 may determine whether or not it is receiving a non-track presence signal at a predetermined reception determination period. Then, when it determines that it is receiving a non-track presence signal transmitted from the track presence detection device N1, the track presence signal receiving device 30 may output the non-track presence signal to the data processing device 10.

[0042] (Emergency light device 40) The emergency light device 40 notifies the user that a person is present in the detection area based on the data processing device 10 determining that a person is present in the detection area. As an example, the presence of a person in the detection area may mean that the person has fallen from the station platform H1. In the following description, the determination process performed by the data processing device 10 to determine whether a person is present in the detection area is also referred to as a "fall detection process."

[0043] For example, the emergency light device 40 may be configured to include a lamp and may notify that it has been determined that a person is present in the detection area by turning on the lamp. Alternatively, the emergency light device 40 may be configured to include a monitor and may notify that it has been determined that a person is present in the detection area by displaying a predetermined color (e.g., red) on the monitor. Alternatively, the emergency light device 40 may notify that a person is present in the detection area by outputting a predetermined sound (warning sound) from a speaker instead of the emergency light device 40.

[0044] The location where the emergency lighting device 40 is installed is not particularly limited. For example, the emergency lighting device 40 may be installed on the station platform H1, or in a station office where station staff are present. Alternatively, the emergency lighting device 40 may be installed in a monitoring center where staff are present to monitor the operation status of the train T1.

[0045] The above describes an example of the configuration of the data processing system 1 according to the embodiment of the present invention.

[0046] [1-2.Details of the data processing system functions] Next, detailed functions of the data processing system 1 according to an embodiment of the present invention will be described. Fig. 4 is a diagram showing a situation A2 around a station platform H1 at the time when a train T1 stops at the station. Fig. 5 is a diagram showing a situation A3 around a station platform H1 at the time when a train T1 starts moving at the station. Fig. 6 is a diagram showing a situation A4 around a station platform H1 at the time when the state of an occupied section C1 changes from an occupied state to an unoccupied state.

[0047] First, as train T1 approaches the station, the state of occupied section C1 changes from an unoccupied state to an occupied state (Fig. 3). Next, train T1 stops at the station to allow passengers to board and disembark between train T1 and station platform H1 (Fig. 4). Next, when it is time for train T1 to depart the station, train T1 begins to move (Fig. 5). Then, the state of occupied section C1 changes from an occupied state to an unoccupied state (Fig. 6).

[0048] In situations A1 to A4, the ranging data acquisition unit 130 acquires ranging data from the ranging device 20 at predetermined time intervals. The ranging data is acquired in units of frames. That is, the predetermined time interval corresponds to the interval between frames acquired by the ranging data acquisition unit 130. The ranging data acquisition unit 130 stores the acquired ranging data in the storage unit 190. The storage unit 190 stores a predetermined number of the most recent frames. Each of situations A1 to A4 will be described in detail below.

[0049] (Transition from non-railway state to railway state) Situation A1 is shown in Figure 3. As described above, situation A1 is the situation around platform H1 of the station at the time when the state of occupied section C1 changes from an unoccupied state to an occupied state.

[0050] The on-track / off-track determination unit 120 functions as a third determination unit that determines whether or not the state of the on-track section C1 has changed from a non-on-track state to a on-track state (second transition) at each predetermined reception determination period, depending on whether or not the condition that the on-track signal was not received by the on-track signal receiving device 30 at the previous reception determination timing and the condition that the on-track signal is received by the on-track signal receiving device 30 at the current reception determination timing are met.

[0051] The method by which the track presence detection device N1 transmits the track presence signal is not limited. As an example, the track presence state may be detected by a track circuit and the track presence signal may be transmitted. The track circuit is configured to include the track presence detection device N1, a power supply device N2, a left rail L1, and a right rail L2. The track presence detection device N1 is electrically connected to portions of the left rail L1 and the right rail L2 that are located at one end of the track presence section C1. Furthermore, the power supply device N2 is electrically connected to portions of the left rail L1 and the right rail L2 that are located at the other end of the track presence section C1.

[0052] When train T1 is not present in the track section C1, the current supplied from power supply N2 flows mainly through the right rail L2, track presence detection device N1, and left rail L1, resulting in a large current detected by track presence detection device N1. On the other hand, when train T1 is present in the track section C1, the current supplied from power supply N2 flows mainly through the right rail L2, the wheelset of train T1, and the left rail L1, resulting in a small current detected by track presence detection device N1.

[0053] Therefore, when the track presence detection device N1 detects a current smaller than a predetermined current or when it does not detect any current, it determines that the train T1 is present in the track presence section C1 and transmits a track presence signal. In this way, a track circuit can be configured.

[0054] When the state of the occupied section C1 is the non-occupied state, the fall detection process is executed by the fall detection unit 160. The fall detection process will be described in detail later.

[0055] Here, let us consider a case where the state of the occupied section C1 changes from a non-occupied state to a presently occupied state. After such a change occurs, even if a person falls from the station platform H1, it is difficult to take measures to avoid contact between the person and the train T1. Therefore, when the occupied / non-occupied train determination unit 120 determines that the state of the occupied section C1 has changed from a non-occupied state to a presently occupied state, the determination control unit 150 stops the fall detection process by the fall detection unit 160.

[0056] (Train T1 stops) Situation A2 is shown in FIG. 4. As described above, situation A2 is the situation around station platform H1 at the time when train T1 stops at the station. Here, the status flag of train T1, which indicates the status of train T1, is set to "moving." The movement stop determination unit 140 functions as a second determination unit that determines whether train T1 is stopped or not based on the distance measurement data (second distance measurement data) obtained by the distance measurement device 20 and acquired from the distance measurement device 20 by the distance measurement data acquisition unit 130.

[0057] Here, the method for determining whether the train T1 is stopped does not need to be limited. As an example, the movement stop determination unit 140 determines whether the train T1 is stopped (i.e., whether the stop condition for the train T1 is satisfied) based on the distance measurement data last acquired from the distance measurement device 20 by the distance measurement data acquisition unit 130 (hereinafter also referred to as "current distance measurement data") and the past distance measurement data stored in the memory unit 190.

[0058] The past ranging data may be ranging data acquired at a single point in time in the past, or may be generated by adding together point clouds included in ranging data acquired at multiple points in time in the past. For example, the past ranging data acquired at multiple points in time may include ranging data acquired m1 frames before the current ranging data to ranging data acquired (m1+n) frames before the current ranging data, where m1 and n are positive integers.

[0059] More specifically, when the status flag of train T1 is set to "moving," the movement / stop determination unit 140 calculates the difference between the point cloud included in the current ranging data and the point cloud included in the past ranging data, and calculates the number of points included in the difference as the difference point number. If the two point clouds are point cloud A and point cloud B, the difference between point cloud A and point cloud B may refer to the point cloud remaining in point cloud A after excluding from point cloud A points included in point cloud A whose distance to any point included in point cloud B is less than a threshold value. Therefore, the difference between point cloud A and point cloud B can also be said to be the point cloud remaining after subtracting point cloud B from point cloud A.

[0060] Fig. 7 is a diagram showing an example of how the differential score changes over time. Fig. 7 shows a graph in which the horizontal axis represents the time (seconds) elapsed since the reference time, and the vertical axis represents the differential score. The horizontal axis indicates whether the state of train T1 is "moving" or "stopped."

[0061] In addition, a "train state determination reference value" is determined in advance. In the following description, it is mainly assumed that the stop determination reference value, which is a reference value for determining whether the state of train T1 is stopped or not, and the movement determination reference value, which is a reference value for determining whether the state of train T1 is moving or not, are the same value. However, the stop determination reference value and the movement determination reference value may be different values.

[0062] When the state of train T1 is "moving", the difference score continues to be equal to or greater than the train state determination reference value. On the other hand, when the state of train T1 is "stopped", the difference score continues to be less than the train state determination reference value.

[0063] Therefore, the movement stop determination unit 140 determines whether the calculated difference score is below the train state determination reference value. The movement stop determination unit 140 counts the number of consecutive times that the calculated difference score is below the train state determination reference value (hereinafter also referred to as the "number of consecutive low differences"), and determines whether the counted number of consecutive low differences is equal to or greater than a predetermined number of consecutive times for stop determination.

[0064] The movement / stop determination unit 140 determines that the train T1 is stopped when the low-difference consecutive count is equal to or greater than the stop determination consecutive count. When the movement / stop determination unit 140 determines that the train T1 is stopped, it clears the low-difference consecutive count by setting it to zero, and sets the train status flag to "stopped."

[0065] Furthermore, if the train T1 is stopped, when a person falls from the station platform H1, it is possible to take measures to prevent contact between the person and the train T1. Therefore, when the movement stop determination unit 140 determines that the train T1 is stopped, the determination control unit 150 starts a fall detection process by the fall detection unit 160.

[0066] (Train T1 begins moving) Situation A3 is shown in FIG. 5. As described above, situation A3 is the situation around station platform H1 at the time when train T1 starts moving at the station. Here, the status flag of train T1 is set to "stopped." The movement / stop determination unit 140 determines whether train T1 is moving or not based on the distance measurement data (third distance measurement data) acquired by the distance measurement data acquisition unit 130 from the distance measurement device 20. At this time, the distance measurement data (third distance measurement data) acquired by the distance measurement device 20 is the distance measurement data acquired by the distance measurement device 20 after the distance measurement data (second distance measurement data) used to determine that train T1 is stopped was acquired by the distance measurement device 20.

[0067] Here, the method for determining whether the train T1 is moving or not does not need to be limited. As an example, the movement stop determination unit 140 determines whether the train T1 is moving or not (i.e., whether the movement condition of the train T1 is satisfied or not) based on the current distance measurement data and the past distance measurement data stored in the storage unit 190.

[0068] When determining whether the train T1 is moving, similarly to when determining whether the train T1 is stopped, the past ranging data may be ranging data acquired at a single point in time in the past, or may be generated by adding together point clouds included in ranging data acquired at multiple past points in time. For example, the ranging data acquired at multiple past points in time may include ranging data acquired m2 frames before the current ranging data to ranging data acquired (m2+n) frames before the current ranging data, where m2 is a positive integer.

[0069] More specifically, when the state flag of train T1 is set to "stopped," the movement / stop determination unit 140 calculates the difference between the point cloud included in the current ranging data and the point cloud included in the past ranging data, and calculates the number of points included in the difference as the difference score. The movement / stop determination unit 140 determines whether the calculated difference score is equal to or greater than a predetermined train state determination reference value. The movement / stop determination unit 140 counts the number of consecutive times that it has determined that the calculated difference score is equal to or greater than the train state determination reference value (hereinafter also referred to as the "consecutive large difference count"), and determines whether the counted consecutive large difference count is equal to or greater than a predetermined consecutive number for movement determination.

[0070] The movement stop determination unit 140 determines that the train T1 is moving when the number of consecutive large differences is equal to or greater than the number of consecutive large differences for movement determination. When the movement stop determination unit 140 determines that the train T1 is moving, it clears the number of consecutive large differences by setting the number of consecutive large differences to zero, and sets the train status flag to "moving."

[0071] Furthermore, if the train T1 is moving, even if a person falls from the station platform H1, it is difficult to take measures to prevent the person from coming into contact with the train T1. Therefore, when the movement stop determination unit 140 determines that the train T1 is moving, the determination control unit 150 stops the fall detection process by the fall detection unit 160.

[0072] (Transition from on-rail state to off-rail state) Situation A4 is shown in Figure 6. As described above, situation A4 is the situation around platform H1 of the station at the time when the state of occupied section C1 changes from an occupied state to an unoccupied state.

[0073] The on-track / off-track determination unit 120 functions as a third determination unit that determines whether or not the state of the on-track section C1 has changed from an on-track state to an off-track state (first transition) at each predetermined reception determination period, depending on whether or not the condition that the on-track signal was received by the on-track signal receiving device 30 at the previous reception determination timing and the condition that the on-track signal has not been received by the on-track signal receiving device 30 at the current reception determination timing are met.

[0074] Here, assume that the state of the occupied section C1 changes from an occupied state to an unoccupied state. After such a change occurs, if a person falls from the station platform H1, it is possible to take measures to prevent contact between the person and the train T1. Therefore, when the occupied / unoccupied train determination unit 120 determines that the state of the occupied section C1 has changed from an occupied state to an unoccupied state, the determination control unit 150 restarts the fall detection process by the fall detection unit 160.

[0075] Note that, for example, if it is not determined that train T1 has stopped, the number of consecutive low differences may not be zero. Alternatively, if it is not determined that train T1 has started moving, the number of consecutive large differences may not be zero. Therefore, when the state of the on-rail section C1 changes from an on-rail state to an off-rail state, the movement / stop determination unit 140 may clear the number of consecutive low differences by setting the number of consecutive low differences to zero, and may clear the number of consecutive large differences by setting the number of consecutive large differences to zero.

[0076] (Summary of whether or not fall detection processing is performed and train status) FIG. 8 is a diagram summarizing the relationship between the situation, the fall detection process, and the state of train T1. In the example shown in FIG. 8, "on track" indicates a situation in which the state of the occupied section C1 has changed from an unoccupied state to an occupied state. "stopped" indicates a situation in which train T1 has stopped. "moving" indicates a state in which train T1 has started moving. "not present on track" indicates a situation in which the state of the occupied section C1 has changed from an unoccupied state to an occupied state.

[0077] As shown in FIG. 8, when the state of the occupied section C1 changes from an unoccupied state to an occupied state, the state of train T1 remains "moving," but the "fall detection process" changes from "enabled" to "disabled." When train T1 stops, the state of train T1 becomes "stopped," and the "fall detection process" changes from "disabled" to "enabled." When train T1 starts moving, the state of train T1 becomes "moving," and the "fall detection process" changes from "enabled" to "disabled." When the state of the occupied section C1 changes from an occupied state to an unoccupied state, the state of train T1 remains "moving," but the "fall detection process" changes from "disabled" to "enabled."

[0078] (Fall detection process details) The storage unit 190 stores data for fall detection in advance. The data for fall detection is also referred to as data for determination processing, and may be past distance measurement data of the detection area obtained by the distance measuring device 20 when no person is present in the detection area. The fall detection unit 160 functions as a first determination unit that performs fall detection processing based on distance measurement data (first distance measurement data) of the detection area obtained by the distance measuring device 20 and acquired from the distance measuring device 20 by the distance measurement data acquisition unit 130. The fall detection processing is a determination processing that determines whether or not a person is present in the detection area.

[0079] More specifically, fall detection unit 160 acquires fall detection data from storage unit 190, and performs fall detection processing based on the difference between the fall detection data and the current distance measurement data for the detection area acquired by distance measurement data acquisition unit 130. When fall detection unit 160 determines that a person is present in the detection area, notification control unit 170 controls emergency light device 40 so that emergency light device 40 notifies that a person is present in the detection area.

[0080] The following explanation mainly focuses on an example in which the fall detection unit 160 sets different detection areas when the state of the occupied section C1 is an unoccupied train state and when the state of the occupied section C1 is an occupied train state. However, the fall detection unit 160 may set the same detection area when the state of the occupied section C1 is an unoccupied train state and when the state of the occupied section C1 is an occupied train state.

[0081] Fig. 9 is a diagram showing an example of a non-occupancy detection area that is set when the state of the occupied section C1 is a non-occupancy state. Referring to Fig. 9, a non-occupancy detection area R1 is shown. In a non-occupancy state, a train is not stopped at the station, and the area in which a person who has fallen from the floor F1 of platform H1 may be present is wide horizontally. For this reason, the non-occupancy detection area R1 is set to be wide horizontally.

[0082] Fig. 10 is a diagram showing an example of an on-train detection area that is set when the state of the on-train section C1 is an on-train state. Referring to Fig. 10, an on-train detection area R2 is shown. In the on-train state, train T1 is stopped at the station, and the area in which a person who has fallen from the floor F1 of platform H1 may be present is narrow horizontally. Therefore, on-train detection area R2 is set to be narrow horizontally.

[0083] However, both the non-occupancy detection area R1 and the on-track detection area R2 are set to include the area between the station platform H1 and the train T1 stopping at the station. The measurement range θ of the distance measuring device 20 is indicated by the angle of the measurement range based on the position of the distance measuring device 20. The distance measuring device 20 is installed on the station platform H1 or in the vicinity of the station platform H1 so that both the non-occupancy detection area R1 and the on-track detection area R2 are included in the measurement range θ of the distance measuring device 20.

[0084] (Detection area R1 when not on the track) The off-rail detection area R1 may include a size determination area R11 for determining the size of an object. The fall detection data stored in the memory unit 190 includes past distance measurement data for the size determination area R11, and the distance measurement data acquired by the distance measurement data acquisition unit 130 includes current distance measurement data for the size determination area R11.

[0085] The fall detection unit 160 identifies an object within the size determination area R11 as the difference between the current distance measurement data of the size determination area R11 and the past distance measurement data of the size determination area R11, and measures the size of the identified object. Note that the size of the object may be the number of difference points, the vertical length or horizontal length of a rectangle surrounding the difference (for example, a rectangle circumscribing the difference), or the length of the longer side of the vertical or horizontal length.

[0086] The fall detection unit 160 may determine whether a person is present in the non-rail detection area R1 based on whether the size of an object exceeds a predetermined size. Note that it is assumed that a person present at a position higher than the floor F1 has a relatively straight body. Therefore, as shown in FIG. 9, if the size determination area R11 includes an area that is higher than the floor F1 of the station platform H1, it is possible to determine with high accuracy whether a person is present in the non-rail detection area R1.

[0087] The non-rail detection area R1 may also include a time determination area R12 for determining the duration of an object's presence. The fall detection data stored in the memory unit 190 includes past distance measurement data for the time determination area R12, and the distance measurement data acquired by the distance measurement data acquisition unit 130 includes current distance measurement data for the time determination area R12.

[0088] The fall detection unit 160 identifies an object within the time determination area R12 as the difference between the current distance measurement data of the time determination area R12 and the past distance measurement data of the time determination area R12, and counts the stay time of the object within the time determination area R12. Note that the stay time may be the time the object continuously stays within the time determination area R12.

[0089] The fall detection unit 160 may determine whether a person is present in the non-rail detection area R1 based on whether the duration of time an object stays in the time determination area R12 exceeds a threshold. In the example shown in Fig. 9, the entire time determination area R12 is included in the size determination area R11. However, only a portion of the time determination area R12 may be included in the size determination area R11, or there may be no overlapping area between the time determination area R12 and the size determination area R11.

[0090] Either the determination of size in the size determination area R11 or the counting of stay time in the time determination area R12 may be performed alone, or both may be performed in combination. When the determination of size in the size determination area R11 and the counting of stay time in the time determination area R12 are performed in combination, the determination of size in the size determination area R11 and the counting of stay time in the time determination area R12 may be performed in parallel, or one may be performed after the other is finished.

[0091] For example, after the size is determined in the size determination area R11, the staying time in the time determination area R12 may be counted. More specifically, the fall detection unit 160 may track an object when it is determined that the size of the object in the size determination area R11 exceeds a predetermined size. Then, the fall detection unit 160 may determine whether a person is present in the non-occupancy detection area R1 based on whether the staying time of the object in the time determination area R12 exceeds a threshold.

[0092] (Detection area R2 when on track) The on-rail detection area R2 may include a size determination area R21 for determining the size of an object, similar to the off-rail detection area R1. The fall detection unit 160 may measure the size of an object within the size determination area R21, and determine whether or not a person is present within the on-rail detection area R2 based on the size of the object, similar to when the person is not present on the rail.

[0093] Similarly to the non-occupancy detection area R1, the on-rail detection area R2 may include a time determination area R22 for determining the dwell time of an object. The fall detection unit 160 may count the dwell time of an object in the time determination area R22, and determine whether or not a person is present in the on-rail detection area R2 based on the dwell time of the object, similar to the non-occupancy detection area R1.

[0094] When a train is present on the line, as when it is not present on the line, either the size determination in the size determination area R21 or the counting of the stay time in the time determination area R22 may be performed alone, or both may be performed in combination.

[0095] (Measurement range θ by distance measuring device 20) As described above, the movement / stop determination unit 140 determines whether the train T1 is stopping or moving based on the difference between the point cloud included in the current distance measurement data and the point cloud included in the past distance measurement data. Therefore, even if the train T1 is moving, if there is little change in the unevenness of the train T1's car body surface that falls within the measurement range θ of the distance measurement device 20, there will be little difference between when the train T1 is stopping and when the train T1 is moving. This prevents improvement in the accuracy of determining whether the train T1 is stopping or moving.

[0096] Therefore, as shown in FIG. 10, it is desirable that the measurement range θ of the distance measuring device 20 includes the upper part of the train T1. For example, multiple air conditioning units are placed at intervals on the upper part of the train T1. Therefore, if the measurement range θ of the distance measuring device 20 includes the upper part of the train T1, when the train T1 starts moving, the unevenness of the surface of the train T1's body that falls within the measurement range θ of the distance measuring device 20 is likely to change, and the difference between when the train T1 is stopped and when the train T1 is moving is likely to differ. This improves the accuracy of determining whether the train T1 is stopped or moving.

[0097] The above has described the details of the functions of the data processing system 1 according to the embodiment of the present invention.

[0098] [1-3. Processing example of data processing system 1] Fig. 11 is a flowchart showing an example of processing executed by the data processing system 1 according to an embodiment of the present invention. With reference to Fig. 11 (and also with reference to Figs. 1 to 10 as appropriate), an example of processing executed by the data processing system 1 according to an embodiment of the present invention will be described. The status flag of train T1, which is a flag indicating the status of train T1, is set to "moving".

[0099] 11, the distance measurement data acquisition unit 130 starts acquiring distance measurement data obtained by the distance measurement device 20 from the distance measurement device 20 at predetermined time intervals (S11). The distance measurement data acquisition unit 130 stores the acquired distance measurement data in the storage unit 190. The storage unit 190 stores a predetermined number of recent frames. In addition, the fall detection unit 160 starts a fall detection process.

[0100] The train presence / non-presence determination unit 120 determines the state of the train presence section C1 (S12). If the state of the train presence section C1 remains unchanged in the non-presence state ("remains unchanged in the non-presence state" in S13), the train presence / non-presence determination unit 120 returns to S12. On the other hand, if the state of the train presence section C1 remains unchanged in the presence state or changes from the non-presence state to the presence state ("remains unchanged in the presence state or changes from the non-presence state to the presence state" in S13), the determination control unit 150 ends the fall detection process by the fall detection unit 160 (S14).

[0101] The movement stop determination unit 140 calculates the difference between the point cloud included in the current distance measurement data and the point cloud included in the past distance measurement data, and calculates the number of points included in the difference as the difference score (S15). The movement stop determination unit 140 determines whether the calculated difference score is below a train state determination reference value (S16).

[0102] When the movement / stop determination unit 140 determines that the calculated difference score is below the train state determination reference value ("YES" in S16), it determines whether the stop condition is satisfied (S17). Note that the stop condition may be satisfied when both the following conditions are satisfied: the number of consecutive low differences, which is the number of consecutive times that the difference score is determined to be below the train state determination reference value, is equal to or greater than a predetermined number of consecutive times for stop determination; and the state flag of train T1 is set to "moving."

[0103] If the stop condition is not satisfied ("NO" in S17), the movement stop determination unit 140 returns to S12. On the other hand, if the stop condition is satisfied ("YES" in S17), the movement stop determination unit 140 clears the number of consecutive low differences by setting the number of consecutive low differences to zero, sets the train status flag to "stopped", starts a fall detection process by the fall detection unit 160 (S18), and returns to S15.

[0104] On the other hand, when the movement / stop determination unit 140 determines that the calculated difference score is equal to or greater than the train state determination reference value ("NO" in S16), it determines whether or not the movement condition is satisfied (S19). Note that the movement condition may be satisfied when both the following conditions are satisfied: the number of consecutive high differences, which is the number of consecutive times that the difference score is equal to or greater than the train state determination reference value, is equal to or greater than a predetermined consecutive number for movement determination, and the state flag of train T1 is set to "stop."

[0105] If the movement condition is not satisfied ("NO" in S19), the movement stop determination unit 140 returns to S15. On the other hand, if the movement condition is satisfied ("YES" in S19), the movement stop determination unit 140 clears the number of consecutive large differences by setting the number of consecutive large differences to zero, sets the train status flag to "moving", ends the fall detection process by the fall detection unit 160 (S20), and returns to S15.

[0106] If the state change in the on-rail section C1 is a change from an on-rail state to an off-rail state ("change from on-rail to off-rail" in S13), the judgment control unit 150 clears the number of consecutive low differences by setting the number of consecutive low differences to zero, clears the number of consecutive high differences by setting the number of consecutive high differences to zero, and starts the fall detection process by the fall detection unit 160 (S21).

[0107] The above has described an example of the processing executed by the data processing system 1 according to the embodiment of the present invention.

[0108] [1-4. Effects of the embodiment] As described above, according to an embodiment of the present invention, a data processing device 10 is provided which includes a fall detection unit 160 that performs a fall detection process to determine whether or not a person is present within a detection area based on distance measurement data of the detection area obtained by a sensor, a movement stop determination unit 140 that determines whether or not the train T1 is stopped based on the distance measurement data obtained by the sensor, and a determination control unit 150 that starts the fall detection process when it is determined that the train T1 is stopped.

[0109] This makes it possible to use the same sensor to determine whether train T1 is stopped and to determine whether a person is present in the detection area. This reduces the probability of sensor failure and makes it possible to reduce sensor operating costs. Furthermore, since there is no need to perform fall detection processing based on detection results output from multiple sensors, the possibility of delays in fall detection processing based on detection results can be reduced.

[0110] The effects of the embodiments of the present invention have been described above.

[0111] <2. Hardware configuration example> Next, an example of the hardware configuration of the data processing device 10 according to the embodiment of the present invention will be described. Below, an example of the hardware configuration of the information processing device 900 will be described as an example of the hardware configuration of the data processing device 10 according to the embodiment of the present invention. Note that the example of the hardware configuration of the information processing device 900 described below is merely one example of the hardware configuration of the data processing device 10. Therefore, the hardware configuration of the data processing device 10 may be such that unnecessary components are deleted from the hardware configuration of the information processing device 900 described below, or new components are added. Note that the hardware of the data processing device 10 can also be realized in a similar manner.

[0112] 12 is a diagram showing a hardware configuration of an information processing device 900 as an example of the data processing device 10 according to an embodiment of the present invention. The information processing device 900 includes a CPU (Central Processing Unit) 901, a ROM (Read Only Memory) 902, a RAM (Random Access Memory) 903, a host bus 904, a bridge 905, an external bus 906, an interface 907, an input device 908, an output device 909, a storage device 910, and a communication device 911.

[0113] The CPU 901 functions as an arithmetic processing unit and control unit, and controls the overall operation of the information processing device 900 in accordance with various programs. The CPU 901 may also be a microprocessor. The ROM 902 stores programs used by the CPU 901, calculation parameters, etc. The RAM 903 temporarily stores programs used in the execution of the CPU 901, parameters that change as appropriate during the execution, etc. These are interconnected by a host bus 904 that is composed of a CPU bus, etc.

[0114] The host bus 904 is connected to an external bus 906, such as a PCI (Peripheral Component Interconnect / Interface) bus, via a bridge 905. It is not necessary to configure the host bus 904, bridge 905, and external bus 906 separately, and these functions may be implemented on a single bus.

[0115] The input device 908 is composed of input means such as a mouse, keyboard, touch panel, buttons, microphone, switches, and levers that allow the user to input information, and an input control circuit that generates an input signal based on the user's input and outputs it to the CPU 901. By operating this input device 908, the user operating the information processing device 900 can input various data to the information processing device 900 and instruct the information processing device 900 to perform processing operations.

[0116] The output device 909 includes, for example, a display device such as a CRT (Cathode Ray Tube) display device, a liquid crystal display (LCD) device, an OLED (Organic Light Emitting Diode) device, or a lamp, and an audio output device such as a speaker.

[0117] The storage device 910 is a device for storing data. The storage device 910 may include a storage medium, a recording device for recording data on the storage medium, a reading device for reading data from the storage medium, and a deletion device for deleting data recorded on the storage medium. The storage device 910 is configured, for example, with an HDD (Hard Disk Drive). This storage device 910 drives a hard disk and stores programs executed by the CPU 901 and various data.

[0118] The communication device 911 is, for example, a communication interface configured with a communication device for connecting to a network, etc. The communication device 911 may be compatible with either wireless communication or wired communication.

[0119] An example of the hardware configuration of the data processing device 10 according to the embodiment of the present invention has been described above.

[0120] <3. Supplementary Information> Although the preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that a person skilled in the art to which the present invention pertains can conceive of various modifications and alterations within the scope of the technical ideas set forth in the claims, and it is understood that these also naturally fall within the technical scope of the present invention. [Explanation of symbols]

[0121] 1. Data Processing System 10 Data Processing Device 20 Ranging device 110 control section 120 Line presence / non-line determination section 130 Distance measurement data acquisition unit 140 Movement stop judgment unit 150 Judgment control unit 160 Fall detection unit 170 Notification control section 190 Storage section

Claims

1. a first determination unit that performs a determination process to determine whether or not a detection target exists within the detection area based on first ranging data of the detection area obtained by the LiDAR; a second determination unit that determines whether a moving object other than the detection target is stopped based on second ranging data obtained by the LiDAR; a determination control unit that starts the determination process when it is determined that the moving object is stopped; A data processing device comprising:

2. The second determination unit determines whether the moving object is moving based on third ranging data obtained by the LiDAR after the second ranging data is obtained by the LiDAR; the determination control unit stops the determination process when it is determined that the moving object is moving.

2. The data processing device according to claim 1.

3. the data processing device includes a third determination unit that determines whether or not a first transition has occurred from a state in which the moving object is present within a predetermined range to a state in which the moving object is not present within the predetermined range after the determination process has been stopped; the determination control unit restarts the determination process when it is determined that the first transition has occurred.

3. The data processing device according to claim 2.

4. the data processing device includes a third determination unit that determines whether or not a second transition has occurred from a state in which the moving object is not present within a predetermined range to a state in which the moving object is present within the predetermined range before the determination process is started; the determination control unit stops the determination process when it is determined that the second transition has occurred.

2. The data processing device according to claim 1.

5. the predetermined range includes a range from a leading position of the moving body when the leading end of the moving body reaches one end of a station platform to a trailing end position of the moving body when the trailing end of the moving body reaches the other end of the platform, 5. A data processing device according to claim 3 or 4.

6. The first determination unit performing the determination process based on a difference between the first distance measurement data and data for determination process stored in advance; 2. The data processing device according to claim 1.

7. the detection area includes a time determination area, the first distance measurement data includes current distance measurement data of the time determination area; the determination processing data includes past distance measurement data of the time determination area, the first determination unit identifies an object in the time determination area based on a difference between current distance measurement data in the time determination area and past distance measurement data in the time determination area, and determines whether the detection target exists in the detection area based on whether a stay time of the object in the time determination area exceeds a threshold.

7. The data processing device according to claim 6.

8. the detection area includes a size determination area, the first distance measurement data includes current distance measurement data of the size determination area; the determination processing data includes past distance measurement data of the size determination area, the first determination unit identifies an object within the size determination area based on a difference between current distance measurement data of the size determination area and past distance measurement data of the size determination area, and determines whether the detection target exists within the detection area based on whether the object exceeds a predetermined size.

7. The data processing device according to claim 6.

9. the size determination area is an area including a position higher than the floor surface of a platform of a station where the moving object stops, 9. A data processing device according to claim 8.

10. The measurement range by the LiDAR includes the upper part of the moving body, 2. The data processing device according to claim 1.

11. The detection area includes an area between a station platform and a moving object stopping at the station.

2. The data processing device according to claim 1.

12. performing a determination process for determining whether or not a detection target exists within the detection area based on first ranging data of the detection area obtained by the LiDAR; Determining whether a moving object other than the detection target is stopped based on second ranging data obtained by the LiDAR; starting the determination process when it is determined that the moving body is stopped; A computer-implemented data processing method, comprising:

13. Computer, a first determination unit that performs a determination process to determine whether or not a detection target exists within the detection area based on first ranging data of the detection area obtained by the LiDAR; a second determination unit that determines whether a moving object other than the detection target is stopped based on second ranging data obtained by the LiDAR; a determination control unit that starts the determination process when it is determined that the moving object is stopped; A program that functions as a

Images