Velocity calculation device, velocity calculation method, and mobile object control system

Abstract

To provide a speed calculation device and a speed calculation method for more accurately measuring speed of a movable body in comparison to a case when a composition of this invention is not provided.SOLUTION: A speed calculation device includes: an overhead wiring position calculation unit 111 for acquiring a first position which is a position of an object with a rail 102 as a reference in a position separated from a sensing unit 108 by a first distance from measured result by the sensing unit 108 installed on a vehicle 101 moving on the rail 102 by measuring the distance from the object such as trolley wire 103 or catenary wire 104 and a second position which is the position of the object with the rail 102 as the reference in a position separated from the sensing unit 108 by a second distance; and an estimated speed determination unit 114 for calculating the speed of the vehicle 101 based on difference from the first distance to the second distance and difference in time where the first position and the second position match.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a speed calculation device, a speed calculation method, and a mobile object control system, and more particularly to a speed calculation device, a speed calculation method, and a mobile object control system that can be suitably used to calculate the speed of a railway vehicle. [Background technology]

[0002] In general, it is difficult to accurately obtain ground speed from a moving object such as a railway vehicle, so in many cases ground speed is calculated by integrating wheel rotation pulses and converting the integrated pulses into speed.

[0003] Patent Document 1 discloses a speed calculation method for calculating the speed of a vehicle from speed pulses generated by the rotation of an axle that rotates the wheels. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-220858 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when wheel rotation pulses are used, the occurrence of phenomena such as wheel spin and skidding makes it difficult to obtain accurate speed. While other methods, such as using rotation pulses from multiple wheels to compensate for wheel spin or using free wheels solely for speed measurement, have been considered, these methods have the drawback of being extremely costly. Furthermore, existing technologies for measuring speed without contact include Doppler velocimeters and spatial filter velocimeters that use laser light or microwaves. However, these Doppler velocimeters and spatial filter velocimeters have the problem that if the distance between the moving body and the target illuminated by the laser light fluctuates depending on the timing of the laser light or microwave irradiation, the range of this distance fluctuation makes it difficult to calculate accurate speed. An object of the present invention is to provide a velocity calculation device and a velocity calculation method that can measure the velocity of a moving object more accurately than when the configuration of the present invention is not provided. [Means for solving the problem]

[0006] In order to solve the above problems, the present invention provides a velocity calculation device that includes a position calculation unit that measures the distance to an object and determines, based on the measurement results of a distance sensor installed on a moving object moving on a trajectory, a first position, which is the position of the object relative to the trajectory at a location a first distance away from the distance sensor, and a second position, which is the position of the object relative to the trajectory at a location a second distance away from the distance sensor, and a velocity calculation unit that calculates the velocity of the moving object based on the difference between the first distance and the second distance and the difference in the time at which the first position and the second position coincide.

[0007] Here, the position of the object changes continuously as the moving object moves. deviation In this case, the number of measurement points for measuring the distance can be increased. Also, the position is continuously deviation The object to be measured can be a railway overhead line, which is less susceptible to environmental changes than other ground facilities. Furthermore, the overhead wire may be at least one of a contact wire and a catenary wire, in which case the speed can be measured more continuously and the speed can be calculated more accurately even if the speed of the vehicle changes. Furthermore, the position calculation unit calculates the position of the contact wire in the left and right directions in response to the movement of the moving body. deviation In this case, the first and second positions can be calculated by changing the contact wire in the left and right direction. deviation This allows for continuous measurement of vehicle speed. Furthermore, the position calculation unit calculates whether the catenary wire moves up or down in response to the movement of the train. deviation In this case, the first position and the second position can be obtained by changing the direction of the catenary wire. deviationThis allows for continuous measurement of vehicle speed. In addition, there may be a plurality of tracks, and the tracks and overhead lines used to determine the first and second positions may be different from those used when the moving object is moving. In this case, it becomes easier to detect the overhead lines.

[0008] Furthermore, the present invention can further include a trajectory calculation unit that calculates the trajectories of the first position and the second position, and the speed calculation unit can calculate the speed of the moving object based on the trajectories. In this case, it is possible to reduce distance measurement errors. The device may further include a trajectory matching unit that finds the time difference by matching the trajectories of the first position and the second position, which makes it possible to find the time difference more accurately.

[0009] The distance sensor may further include a trajectory recognition unit that extracts a first point group corresponding to the trajectory as a plurality of points whose distances are measured by the distance sensor, and the position calculation unit may determine the first and second positions based on a trajectory plane that is a plane including the first point group. In this case, the first and second positions can be measured more accurately. Furthermore, the system further includes an object recognition unit that extracts a second point cloud corresponding to the object at the first position and the second position as the multiple points whose distances are measured by the distance sensor, and the position calculation unit classifies the second point cloud by distance and calculates the first distance and the second position by performing coordinate system transformation based on the trajectory plane. In this case, the first position and the second position can be measured more accurately. The distance sensor measures distances on at least three planes that intersect with the moving direction of the moving object, and the trajectory recognition unit extracts a first point cloud from the measurement results on the plane at one of the at least three distances, and extracts a second point cloud from the measurement results on the plane at a distance other than the one distance. In this case, it becomes easier to extract the first point cloud and the second point cloud. Furthermore, the points may be acquired from a distance sensor attached to the side of the vehicle relative to the center line in the vertical direction on a plane intersecting the direction of movement of the moving object, thereby enabling more information on the characteristic points of the object to be captured.

[0010] The present invention also provides a velocity calculation method that measures the distance to an object and, based on the measurement results of a distance sensor installed on a moving object moving on a trajectory, determines a first position, which is the position of the object relative to the trajectory at a location a first distance away from the distance sensor, and a second position, which is the position of the object relative to the trajectory at a location a second distance away from the distance sensor, and calculates the velocity of the moving object based on the difference between the first distance and the second distance and the difference in time at which the first position and the second position coincide.

[0011] Furthermore, the present invention is a mobile body control system comprising: a velocity calculation device that calculates the velocity of a mobile body moving on a trajectory; and a control device that controls the movement of the mobile body based on the calculated velocity, wherein the velocity calculation device comprises a position calculation unit that measures the distance to an object and, based on the measurement results of a distance sensor installed on the mobile body, determines a first position, which is the position of the object based on the trajectory at a location a first distance away from the distance sensor, and a second position, which is the position of the object based on the trajectory at a location a second distance away from the distance sensor; and a velocity calculation unit that calculates the velocity of the mobile body based on the difference between the first distance and the second distance and the difference in time at which the first position and the second position coincide. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a velocity calculation device and a velocity calculation method that can measure the velocity of a moving object more accurately than when the configuration of the present invention is not provided. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a conceptual diagram showing the overall configuration of a train control system according to an embodiment of the present invention. [Figure 2]1 is a cross-sectional view of a vehicle taken along a plane perpendicular to the direction of travel of the vehicle. [Figure 3] 4 is a flowchart illustrating the operation of the vehicle speed recognition system. [Figure 4] 1(a) and 1(b) are diagrams showing how the contact wire is installed. [Figure 5] FIG. 2 is a diagram illustrating a rail plane and a coordinate system based on the rail plane. [Figure 6] 4(a) to 4(c) are diagrams illustrating steps S105 to S107 in FIG. 3 in more detail. [Figure 7] FIG. 4 is a diagram illustrating steps S105 to S107 in FIG. 3 in more detail. [Figure 8] 10(a) and 10(b) are diagrams showing a case where the speed of a vehicle is calculated when a catenary wire is used. [Figure 9] FIG. 10 is a diagram illustrating a case where the speed of a vehicle is calculated when a catenary wire is used. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. [First embodiment] First, the first embodiment will be described. In the first embodiment, the left and right direction of the trolley wire 103 of the overhead wire of the railway is deviation A case where the velocity of a moving object is calculated using the above formula will be described.

[0015] <Explanation of the overall configuration of train control system 1> FIG. 1 is a conceptual diagram showing the overall configuration of a train control system 1 according to the present embodiment. The train control system 1 shown in the figure is an example of a mobile object control system. The train control system 1 includes a vehicle speed recognition system 100 and a control unit 115. The illustrated vehicle speed recognition system 100 is installed in a vehicle 101, which is an example of a moving body. The vehicle 101 is a railway vehicle. The vehicle 101 is supplied with power via a pantograph Pn from electrical wiring equipment D provided along left and right rails 102, which are an example of a track, to drive an electric motor or the like (not shown). The vehicle 101 then moves on the rails 102 by the driving force of the driven electric motor or the like. The vehicle speed recognition system 100 functions as a speed calculation device that calculates the speed of the vehicle 101 moving on the rails 102.

[0016] Typical components of the electric circuit facility D include the contact wire 103 that contacts the vehicle 101 at the pantograph Pn, the catenary wire 104 and hanger 105 that suspend and support the contact wire 103, and the supports 106 and insulators 107 that support them. In addition to these, the electric circuit facility D is usually composed of various other elements (not shown), such as tension adjusters, power supply branching devices, and insulating insulators. Hereinafter, unless otherwise specified, these components that make up the electric circuit facility D above the vehicle 101 will be collectively referred to as the "overhead line."

[0017] The vehicle speed recognition system 100 includes a sensing unit 108, an overhead contact line recognition unit 109, a rail surface recognition unit 110, an overhead contact line position calculation unit 111, overhead contact line trajectory calculation units 112-1 to 112-N, an overhead contact line trajectory matching unit 113, and an estimated speed determination unit 114.

[0018] The sensing unit 108 is a distance sensor that measures distance, such as a LIDAR (Light Detection and Ranging) sensor. The LIDAR scans the overhead wires and rails 102 to measure their three-dimensional shapes. The sensing unit 108 then transmits data of the three-dimensional shapes (measurement data) to the overhead wire recognition unit 109 and the rail surface recognition unit 110. Here, LIDAR is a device that measures the distance to an object by irradiating the object with a laser and receiving the reflected light. Due to its principle, the accuracy of distance measurement is relatively high, ranging from a few mm to a few cm. LIDAR uses a single straight-traveling laser as its basic unit, and captures the surface shape of the object as a collection of minute points (point cloud) by periodically changing the direction of irradiation at a high speed of several tens of Hz. For this reason, the measurement data described above is data (data group) that expresses the three-dimensional shape of the overhead wires and rails 102 as a point cloud.

[0019] It is preferable that the sensing unit 108 is a three-dimensional LIDAR that can change the direction of irradiation three-dimensionally. However, there is also another type of LIDAR, a two-dimensional LIDAR that changes the direction of irradiation two-dimensionally, and even if these are used alone or in combination, it is possible to similarly capture the surface shape of the target (although the amount of information that can be obtained at one time is less than when using a three-dimensional LIDAR), and the contents described below can be similarly implemented.

[0020] FIG. 2 is a cross-sectional view of the vehicle 101 taken along a plane perpendicular to the traveling direction of the vehicle 101. As shown in FIG. Hereinafter, the positional relationship between the vehicle 101, the sensing unit 108, and the overhead wires (trolley wire 103, messenger wire 104, hanger 105, support 106, and insulator 107) will be described in detail with reference to FIG. The sensing unit 108 is installed at a location that passes through the junction between the pantograph Pn and the contact wire 103 and is off the center line C in the vertical direction of the vehicle 101. This can also be said to mean that the sensing unit 108 is attached to the side of the vehicle 101 relative to the center line C in the vertical direction on a plane that intersects with the direction of movement of the vehicle 101. As a result, the LIDAR, which is the sensing unit 108, is installed on the vehicle 101 so that it can scan the overhead wires from an oblique direction. This is because capturing more information about the characteristic points of the overhead wires is advantageous for subsequent processing (the matching process described in FIG. 5 ), and is intended to capture as many components of the overhead wires as possible. For example, if the sensing unit 108 is installed on the center line C and scanning is performed from a position directly below the contact wire 103, the hanger 105 and the messenger wire 104 that suspend the contact wire 103 in the vertical direction will be hidden behind the contact wire 103 and will not be scanned. In contrast to this, in this embodiment, the sensing unit 108 is provided at a position that is shifted from directly below the contact wire 103 and away from the center line C, and scanning is performed obliquely from that position. This allows the scan to cover the periodically stretched hanger 105 and the side of the messenger wire 104 that shows periodic deflection, and these features can be incorporated into the measurement data.

[0021] Here, a supplementary explanation will be given regarding the shape of the support 106. Because the support 106 needs to support all structures below it, including the catenary wire 104 and the contact wire 103, it is usually made of a strong material such as a steel frame and is particularly large in size among the structures of the overhead line. This makes it relatively easy to capture its three-dimensional shape with LIDAR. Furthermore, there is no need to worry about the support 106 bending or swaying like an electric wire. Therefore, it looks the same every time the vehicle 101 travels, and there is relatively little risk of it being overlooked. Therefore, it can be said that it is easy to capture with a LIDAR scan. The support 106 is usually erected at intervals of several hundred meters.

[0022] Next, the configuration of the vehicle 101 other than the sensing unit 108 will be described. The overhead line recognition unit 109 is an example of an object recognition unit, and extracts measurement data (measurement results) of the overhead line from the measurement data acquired from the sensing unit 108 and passes it to the overhead line position calculation unit 111. The rail surface recognition unit 110 is an example of a track recognition unit, and extracts measurement data (measurement results) of the top surface of the rail 102 from the measurement data acquired from the sensing unit 108 and passes it to the overhead line position calculation unit 111. The overhead line position calculation unit 111 is an example of a position calculation unit, and calculates the overhead line position based on the surfaces of two (a pair of) rails on the basis of measurement data. Here, the overhead line position calculation unit 111 classifies the overhead line positions by distance. Here, the overhead line position calculation unit 111 classifies the positions into N ways (1 to N) by distance. The overhead line trajectory calculation units 112-1 to 112-N are an example of a trajectory calculation unit, and calculate the trajectory of the overhead line position calculated by the overhead line position calculation unit 111. At this time, the overhead line trajectory calculation units 112-1 to 112-N each calculate the trajectory of one overhead line position. That is, the overhead line trajectory calculation units 112-1 to 112-N calculate the trajectories of N overhead line positions by distance. Note that hereinafter, when the overhead line trajectory calculation units 112-1 to 112-N are not to be distinguished from one another, they may be simply referred to as the "overhead line trajectory calculation unit 112." The overhead wire trajectory matching unit 113 is an example of a trajectory matching unit, and matches overhead wire trajectories at a plurality of locations (N locations) calculated by the overhead wire trajectory calculation units 112-1 to 112-N with each other, and calculates the time intervals and distance intervals between them. The estimated speed determination unit 114 is an example of a speed calculation unit, and calculates the speed V of the vehicle 101 from the time intervals and distance intervals between overhead line portions found by the overhead line trajectory matching unit 113 and transmits the calculated speed V to the control unit 115.

[0023] The control unit 115 is an example of a control device that controls the movement of the vehicle 101 based on the speed calculated by the vehicle speed recognition system 100. The control unit 115 is, for example, a vehicle control application that operates using the estimated speed of the vehicle 101. An example of the control unit 115 is an automatic train operation (ATO) system that automatically controls acceleration and deceleration so that the vehicle 101 travels between predetermined points (for example, between stations) according to a scheduled time (diagram). In addition to ATO, a signaling system (ATP: Automatic Train Protection) that controls braking to ensure a safe distance between vehicles is also an example of an application that uses the estimated speed of the vehicle 101.

[0024] Note that some or all of the functions of the vehicle speed recognition system 100 can be realized by a computer device that operates through cooperation between software and hardware resources. That is, a central processing unit (CPU) (not shown) inside a computer provided in the vehicle speed recognition system 100 executes programs that realize each function, thereby realizing each function. The programs are stored in storage such as a hard disk drive (HDD) or a solid state drive (SSD) or an auxiliary storage device such as a read-only memory (ROM), and are loaded from the auxiliary storage device into a main storage device (random access memory (RAM)) and executed therein. These functions can also be realized by hardware such as a dedicated circuit.

[0025] <Description of Operation of Vehicle Speed ​​Recognition System 100> Next, the operation of the vehicle speed recognition system 100 will be described. FIG. 3 is a flowchart illustrating the operation of the vehicle speed recognition system 100. 3 (steps S101 to S108) are executed by the vehicle speed recognition system 100. Each step will be described below. In step S101, three-dimensional point cloud data is acquired as measurement data from a sensing unit 108 installed so as to be able to observe the rail 102 and the overhead wires (trolley wire 103, messenger wire 104, hanger 105, support 106, and insulator 107). In the first embodiment, the speed is detected using the deviation of the trolley wire 103.

[0026] 4(a) and 4(b) are diagrams showing a state in which the trolley wire 103 is installed. As shown in Figures 4(a) and 4(b), the vehicle 101 receives high voltage through sliding contact of the contact plates provided on the pantograph Pn with the trolley wire 103, and travels on the left and right rails 102. In order to ensure uniform wear of the contact plates, the contact wires 103 are pulled outward for each utility pole and are installed with a zigzag offset (left-right offset) as shown in Figure 4(b). More specifically, as the vehicle 101 travels, the contact wires 103 move in directions that intersect (in this case, the left-right direction of the vehicle 101) around the center line 102m of the left and right rails 102. deviation In other words, the trolley wire 103 moves left and right in response to the movement of the vehicle 101. deviation As a result, the position of the trolley wire 103 changes in the left-right direction when viewed from the vehicle 101. In this case, the position of the trolley wire 103 changes regularly in the left-right direction around the center line 102m when viewed from the vehicle 101. In this embodiment, as will be described below, the speed is detected by utilizing the lateral deviation of the trolley wire 103.

[0027] Returning to FIG. 3, in step S102, the overhead contact line recognition unit 109 extracts a point cloud obtained by measuring the overhead contact line including the contact wire 103 from the measurement data acquired from the sensing unit .

[0028] In step S103, the rail surface recognition unit 110 extracts a point cloud obtained by measuring the upper surfaces of the left and right rails 102 on which the vehicle 101 is traveling, from the measurement data acquired from the sensing unit 108. Furthermore, the rail surface recognition unit 110 extracts a rail plane (track plane) Hr as a plane including the extracted point clouds.

[0029] In step S104, the overhead line position calculation unit 111 converts the point cloud acquired by the overhead line recognition unit 109 into a coordinate system based on the rail plane Hr acquired in step S103, and classifies them by distance from the vehicle 101 (for example, into N ways from 1 to N by distance). Here, the coordinate system based on the rail plane Hr is a coordinate system defined using the rail plane Hr extracted by the rail surface recognition unit 110. In step S104, the overhead line position calculation unit 111 converts the positions of the point cloud acquired by the overhead line recognition unit 109 into positions in this coordinate system.

[0030] FIG. 5 is a diagram illustrating the rail plane Hr and a coordinate system based on the rail plane Hr. As shown in the figure, the rail plane Hr is a plane that passes through the upper surfaces of the left and right rails 102. The X-axis, Y-axis, and Z-axis directions are also shown as a coordinate system based on the rail plane Hr. The X-axis direction is the traveling direction of the vehicle 101. The Y-axis direction is defined as a direction perpendicular to the traveling direction of the vehicle 101, extending leftward. The Z-axis direction is defined as a direction perpendicular to the traveling direction of the vehicle 101, extending upward. The position of the trolley wire 103 can be considered as the distance Yc from a plane Hz extending in the Z direction from the center line 102m of the left and right rails 102. It can also be said that the distance Yc represents the position of the trolley wire 103 when the rail plane Hr is used as the reference.

[0031] 3 again, in step S105, the overhead contact line trajectory calculation units 112-1 to 112-N calculate overhead contact line trajectories 1 to N, respectively, from each point cloud classified (1 to N) by distance from the vehicle 101. That is, the overhead contact line trajectory calculation units 112-1 to 112-N calculate the trajectories of positions at distances Yc at positions on the contact wire 103 at N different distances from the vehicle 101 as overhead contact line trajectories 1 to N.

[0032] In step S106, the overhead line trajectory matching unit 113 matches the overhead line trajectories 1 to N with each other, and obtains a set of a time interval ΔTn and a distance interval ΔDn between the matched trajectories. In step S107, the estimated speed determination unit 114 calculates the speed V of the vehicle 101 from the set of the time interval ΔTn and the distance interval ΔDn acquired in step S106 using the formula V=ΔDn / ΔTn. In step S108, the speed V of the vehicle 101 acquired in step S107 is output to the control unit 115, and the process ends.

[0033] 6(a) to 6(c) and FIG. 7 are diagrams illustrating steps S105 to S107 in FIG. 3 in more detail. Of these, Fig. 6(a) is a view of the vehicle 101, rail 102, and trolley wire 103 as seen from above. Also, Figs. 6(b) and 6(c) are views as seen from the VIbc direction of Fig. 6(a), and are views of the vehicle 101, rail 102, and trolley wire 103 as seen along the Y direction.

[0034] In the above description, it has been assumed that the positions of the contact wire 103 at N distances are acquired in step S105 in the overhead line trajectory calculation units 112-1 to 112-N, but in the following description, for simplicity, a case where N=2 will be described. That is, the overhead line trajectory calculation unit 112 obtains the trajectory of two overhead line positions (overhead line trajectory). That is, the overhead line trajectory calculation unit 112 calculates the trajectory of positions at a distance Yc between the two overhead line positions.

[0035] The sensing unit 108 is a LIDAR with three two-dimensional scan planes. In Figures 6(a) to 6(c), these are illustrated as scan plane A, scan plane B, and scan plane R. Of these, scan plane R is used to measure the distance to the top surfaces of the left and right rails 102 and extract the rail plane Hr. Scan planes A and B are also used to measure the contact wire 103 and calculate the distance Yc between the contact wire 103 and its two positions.

[0036] When the vehicle 101 travels, the position of the point cloud observed on scan plane A in the direction perpendicular to the traveling direction (Y direction) fluctuates as shown by curve A in the graph of Figure 7. Similarly, the position of the point cloud observed on scan plane B fluctuates as shown by curve B. In Figure 7, the horizontal axis represents time T, and the vertical axis represents distance Yc. Here, the points where the scan plane A and the scan plane B cross the contact wire 103 are at a substantially constant distance from the vehicle 101, and this distance is defined as L A , L B In this embodiment, the distance L A is an example of the first distance, and the distance L B is an example of the second distance. Curve A in the graph of FIG. 7 represents the distance between the sensing unit 108 and the distance L A The distance L represents the position of the trolley wire 103 at a distance Yc relative to the rail 102, and can be considered as its locus. A The position at distance Yc in the graph of FIG. 7 is an example of a first position, which is the position of the object based on the trajectory. B The distance L represents the position of the trolley wire 103 at a distance Yc relative to the rail 102, and can be regarded as its locus. B The position at the distance Yc at is an example of a second position, which is the position of the object based on the trajectory.

[0037] At this time, the overhead line trajectory calculation unit 112 may perform fitting using a known method such as the least squares method to calculate the trajectory. In other words, the distance measured by the sensing unit 108 may contain measurement errors. By performing fitting when drawing the curve A and the curve B, it is possible to reduce measurement errors and obtain more accurate trajectories. As a result, the distance Yc can be determined more accurately.

[0038] 6(c) 。 Then, when the curve B in the graph of FIG. 7 is shifted by a certain time interval ΔTn, it roughly coincides with the curve A. This means that the same position of the contact wire 103 is measured at a time interval ΔTn. In other words, the vehicle 101 located at the position shown in FIG. 6(b) measures the position P of the contact wire 103 on the scan plane A. Then, after the time interval ΔTn has elapsed, the vehicle 101 moves to the position shown in FIG. 6(c) and measures the same position P of the contact wire 103 on the scan plane B. This time interval ΔTn can be obtained by the overhead contact line trajectory matching unit 113 matching the curve A and the curve B. In other words, the amount of shift when either the curve A or the curve B is shifted in the time direction and coincides with the other is defined as the time interval ΔTn.

[0039] Then, the estimated speed determination unit 114 calculates the speed V of the vehicle 101 by multiplying these distances L A , L B , ΔTn, V is calculated by the formula V=ΔDn / ΔTn. ΔDn is the distance L A and L B is the distance between A -L B In this way, the estimated speed determination unit 114 determines the distance L A and distance L B The difference (distance interval ΔDn) and the distance L A Position of distance Yc and distance L B The speed of the vehicle 101 can be calculated based on the difference in time (time interval ΔTn) between the positions of the vehicle 101 at distance Yc and the vehicle 101 at distance L. A Position of distance Yc and distance L B The respective loci of the positions of the distance Yc at the points are obtained, and then the respective loci are matched by the overhead line locus matching unit 113. By using the loci, the accuracy of the time interval ΔTn is improved.

[0040] In this case, it can also be said that in step S103 of FIG. 3, a first point group corresponding to the rail 102 is extracted as a plurality of points to which the distance is measured by the sensing unit 108. Furthermore, in step S102 of FIG. 3, the distance L A Position of distance Yc and distance L B In other words, a second point group corresponding to the contact wire 103 at a position of distance Yc at the point is extracted. Furthermore, in step S104 of FIG. 3, the overhead line position calculation unit 111 calculates the distance L A Position of distance Yc and distance L B In step S104, the overhead line position calculation unit 111 classifies the second point group by distance and performs coordinate system transformation using the rail plane Hr as a reference to calculate the distance L A Position of distance Yc and distance L B It can also be said that the position of the distance Yc is calculated. 3, the sensing unit 108 measures distances on surfaces at least at three distances that intersect with the direction of travel of the vehicle 101. Then, in step S103, the rail surface recognition unit 110 extracts a first point cloud from the measurement results on a surface at one of the at least three distances (in this case, scan surface R), and in step S102, it extracts a second point cloud from the measurement results on surfaces at distances other than this one distance (in this case, scan surfaces A and B).

[0041] [Second embodiment] Next, a second embodiment will be described. In the second embodiment, a trolley wire 103 is used as a railway overhead line. deviation Instead, the vertical direction of the catenary wire 104 deviation is used to calculate the speed of the moving object. If there is little or no deviation in the left-right direction of the trolley wire 103, it may be difficult to determine the speed of the vehicle 101 from the trolley wire 103. Therefore, in the second embodiment, the object observed by the sensing unit 108 is the catenary wire 104 instead of the trolley wire 103.

[0042] The functional configuration of the vehicle speed recognition system 100 of the second embodiment is the same as that shown in Fig. 1. That is, like the first embodiment, the train control system 1 includes the vehicle speed recognition system 100 and a control unit 115. The vehicle speed recognition system 100 also includes a sensing unit 108, an overhead contact line recognition unit 109, a rail surface recognition unit 110, an overhead contact line position calculation unit 111, overhead contact line trajectory calculation units 112-1 to 112-N, an overhead contact line trajectory matching unit 113, and an estimated speed determination unit 114.

[0043] 8(a) to 8(b) and FIG. 9 are diagrams showing a case where the speed of the vehicle 101 is calculated when the catenary wire 104 is used. 8(a) and 8(b) are views of the vehicle 101 and the like viewed from the same direction as in FIGS. 6(b) and 6(c). In this case, the vehicle 101, rails 102, and catenary wires 104 are shown as viewed along the Y direction. Then, as in the first embodiment, scan plane R is used to measure the distance to the top surfaces of the left and right rails 102 and extract the rail plane Hr. On the other hand, scan planes A and B measure the catenary wire 104 and measure the vertical (Z-direction) positions of the catenary wire 104 at two different distances relative to the rail plane Hr. The catenary wire 104 is installed so as to bend in the vertical direction (Z direction) as shown in the figure. In other words, the catenary wire 104 bends in the vertical direction (Z direction) as the vehicle 101 travels. deviation Therefore, when viewed from the vehicle 101, the position of the messenger wire 104 changes in the vertical direction. When viewed from the vehicle 101, the position of the messenger wire 104 changes regularly in the vertical direction.

[0044] When the vehicle 101 travels, the position of the point cloud observed on scan plane A in the direction perpendicular to the traveling direction fluctuates as shown by curve A in the graph of Fig. 9. Similarly, the position of the point cloud observed on scan plane B fluctuates as shown by curve B. In Fig. 9, the horizontal axis represents time T, and the vertical axis represents the distance Zc between the rail plane Hr and the catenary wire 104.

[0045] As in the first embodiment, the overhead contact wire trajectory calculation unit 112 may perform fitting using a known method such as the least squares method to calculate the trajectory, thereby making it possible to more accurately determine the distance Zc between the rail plane Hr and the messenger wire 104.

[0046] In the following, the trolley wire 103 is replaced with the catenary wire 104 and the distance Yc is replaced with the distance Zc, so that the embodiment is almost the same as the first embodiment. That is, the points where the scan planes A and B cross the catenary wire 104 are at a substantially constant distance from the vehicle 101, and this distance is defined as L A , L B 9. The curve A in the graph of FIG. 9 represents the distance between the sensing unit 108 and the distance L A It represents the distance Zc, which is the position of the catenary wire 104 relative to the rail 102 at a distant location, and can be understood as its trajectory. A The position at distance Zc in the graph of FIG. 9 is an example of a first position, which is the position of the object based on the trajectory. B It represents the distance Zc, which is the position of the catenary wire 104 relative to the rail 102 at a distant location, and can be understood as its trajectory. B The position at distance Zc at is an example of a second position, which is the position of the object based on the trajectory.

[0047] Furthermore, when curve B in the graph of FIG. 9 is shifted by a certain time interval ΔTn, it roughly matches curve A. This means that the same position of the catenary wire 104 is measured with a shift of the time interval ΔTn. In other words, the vehicle 101, which was located at the position shown in FIG. 8(a), measures position P of the catenary wire 104 on scan plane A. Then, after the time interval ΔTn has elapsed, the vehicle 101 moves to the position shown in FIG. 8(b), and measures the same position P of the catenary wire 104 on scan plane B. This time interval ΔTn can be found by the catenary wire trajectory matching unit 113 matching curve A and curve B. In other words, the amount of shift when either curve A or curve B is shifted in the time direction and it matches the other is defined as the time interval ΔTn. Then, the estimated speed determination unit 114 calculates the speed V of the vehicle 101 by multiplying these distances L A , L B , ΔTn, it is calculated by the formula V=ΔDn / ΔTn.

[0048] According to the above-described aspects, in the first embodiment, the three-dimensional shape of the contact wire 103 is used as the electric power supply circuit equipment D deployed above the vehicle 101, thereby making it possible to recognize with high reliability the speed of the vehicle 101 traveling on the rail 102. In addition, in the second embodiment, the three-dimensional shape of the catenary wire 104 is used as the electric power supply circuit equipment D deployed above the vehicle 101, thereby making it possible to recognize with high reliability the speed of the vehicle 101 traveling on the rail 102. In this embodiment, compared to when wheel rotation pulses are used, the speed can be calculated more accurately because it is not affected by wheel spin or skid. Furthermore, compared to methods using a Doppler speedometer or a spatial filter speedometer that uses laser light or microwaves, by using the rail plane Hr as a reference and using the positions of distance Yc and distance Zc, even if the distance between the sensing unit 108 and an object such as an overhead wire changes, the speed can be calculated more accurately because it is less affected. Furthermore, by calculating the speed of the vehicle 101 based on these trajectories, the speed can be calculated more accurately. Furthermore, for the same reason, it is also less affected by vibrations of the vehicle 101. Therefore, this embodiment enables robust speed detection. Furthermore, when using contact wires 103 and catenary wires 104, the system is less susceptible to environmental changes than when using other ground facilities. For example, when using electrical wiring facilities D, the system is less susceptible to snow accumulation. In addition, in this case, there is no need to rely on GPS (Global Positioning System) or map information.

[0049] In the above detailed example, a railway overhead wire is used as the object for which distance is to be measured. The overhead wire is at least one of the contact wire 103 and the messenger wire 104. However, the overhead wire is not limited to this. For example, the hanger 105, the support 106, and the insulator 107 may also be the object for which distance is to be measured. Furthermore, the object for which distance is to be measured is not limited to the overhead wire, and ground equipment installed near the moving object may also be the object for which distance is to be measured.

[0050] However, the position of the object changes continuously as the vehicle 101 moves. deviation In other words, it is preferable that the object is a structure in which the position changes continuously, such as the trolley wire 103 or the catenary wire 104. deviation It is preferable to be able to measure the position continuously. In this case, there are more measurement points for measuring distance, which reduces measurement errors and allows the position of the object to be measured more accurately. Furthermore, even if the speed of the vehicle 101 changes, the speed can be calculated more accurately. In other words, by being able to measure the position continuously, the speed of the vehicle 101 can be calculated in real time, so to speak. This can also be said to provide good responsiveness when calculating the speed of the vehicle 101. However, when the hanger 105, the support 106, the insulator 107, etc. are taken as objects, these are installed discretely at a predetermined distance apart. Therefore, although the speed of the vehicle 101 can be calculated, if the speed of the vehicle 101 changes, the speed of the vehicle 101 cannot necessarily be calculated responsively. For example, as described above, the support 106 has the advantage of being large and easy to capture with the sensing unit 108. However, because the support 106 is installed at intervals of, for example, several hundred meters, calculating the speed of the vehicle 101 based on this does not necessarily result in a responsive calculation.

[0051] In the above-described example, the contact wire 103 and the messenger wire 104 are regularly deviation However, this is not limited to this case, and it may also be used irregularly. deviation You may do so. In the first embodiment, the trolley wire 103 is oriented in the left-right direction around the center line 102m. deviationThe case where the center line is 102m is explained. deviation You don't have to.

[0052] In the above detailed example, the rails 102 and overhead wires used when the vehicle 101 moves are used to measure the distance and calculate the speed of the vehicle 101, but the present invention is not limited to this. For example, if there are multiple tracks, the tracks and overhead wires used to measure distance may be different from those used when the vehicle 101 is moving. In other words, in a double-track section, it is also possible to use the adjacent track on which the adjacent vehicle (in this case, an oncoming train) is running and the overhead wires erected on that track. For example, in FIG. 4, the vehicle 101 is running on the left and right rails 102 located on the left side of the figure, but this corresponds to a case where the left and right rails 102 located on the right side of the figure and the overhead wires on them are used. Of course, this can also be applied to quadruple tracks, triple-quadruple tracks, etc.

[0053] <Explanation of speed calculation method> Here, the processing performed by the speed recognition system 100 measures the distance to an object such as a trolley wire 103 or a catenary wire 104, and calculates the distance L from the sensing unit 108 based on the measurement result of the sensing unit 108 installed in the vehicle 101 moving on the rail 102. A The first position, which is the position of the object relative to the rail 102 at a distant location, is the distance L B A second position, which is the position of the object at a distant location relative to the rail 102, is calculated, and the distance L A and distance L B This can be considered as a speed calculation method that calculates the speed of the vehicle 101 based on the difference (distance interval ΔDn) between the first position and the second position, and the difference (time interval ΔTn) between the times when the first position and the second position coincide.

[0054] Although the present embodiment has been described above, the technical scope of the present invention is not limited to the scope of the above embodiment. It is clear from the claims that various modifications and improvements to the above embodiment are also included in the technical scope of the present invention. [Explanation of symbols]

[0055] 1...train control system, 100...speed recognition system, 101...vehicle, 102...rail, 103...trolley wire, 104...messenger wire, 108...sensing unit, 109...overhead wire recognition unit, 110...rail surface recognition unit, 111...overhead wire position calculation unit, 112-1 to 112-N...overhead wire trajectory calculation unit, 113...overhead wire trajectory matching unit, 114...estimated speed determination unit, 115...control unit, D...electrical circuit equipment, Hr...rail surface

Claims

1. a position calculation unit that measures a distance to an object and, based on a measurement result of a distance sensor installed on a moving body moving on a trajectory, calculates a first position, which is the position of the object at a location separated by a first distance from the distance sensor and with the trajectory as a reference, and a second position, which is the position of the object at a location separated by a second distance from the distance sensor and with the trajectory as a reference; a speed calculation unit that calculates a speed of the moving object based on a difference between the first distance and the second distance and a difference between a time when the first position and the second position coincide; Equipped with A velocity calculation device in which the position of the object continuously shifts as the moving body moves.

2. 2. The velocity calculation device according to claim 1, wherein the object whose position continuously deviates is a railway overhead wire.

3. 3. The speed calculation device according to claim 2, wherein the overhead wire is at least one of a contact wire and a messenger wire.

4. The velocity calculation device according to claim 3 , wherein the position calculation unit determines the first position and the second position, which change as the trolley wire deviates in the left-right direction in response to movement of the moving body.

5. The speed calculation device according to claim 3 , wherein the position calculation unit determines the first position and the second position, which change due to vertical deviation of the catenary wire in response to movement of a train.

6. 3. The velocity calculation device according to claim 2, wherein there are a plurality of tracks, and the tracks and the overhead lines used to determine the first position and the second position are different from those used when the moving body is moving.

7. a position calculation unit that measures a distance to an object and, based on a measurement result of a distance sensor installed on a moving body moving on a trajectory, calculates a first position, which is the position of the object at a location separated by a first distance from the distance sensor and with the trajectory as a reference, and a second position, which is the position of the object at a location separated by a second distance from the distance sensor and with the trajectory as a reference; a speed calculation unit that calculates a speed of the moving object based on a difference between the first distance and the second distance and a difference between a time when the first position and the second position coincide; a locus calculation unit that calculates loci of the first position and the second position; Equipped with The speed calculation unit is a speed calculation device that calculates the speed of the moving object based on the trajectory.

8. The velocity calculation device according to claim 7 , further comprising a trajectory matching unit that finds the time difference by matching the trajectories of the first position and the second position.

9. a position calculation unit that measures a distance to an object and, based on a measurement result of a distance sensor installed on a moving body moving on a trajectory, calculates a first position, which is the position of the object at a location separated by a first distance from the distance sensor and with the trajectory as a reference, and a second position, which is the position of the object at a location separated by a second distance from the distance sensor and with the trajectory as a reference; a speed calculation unit that calculates a speed of the moving object based on a difference between the first distance and the second distance and a difference between a time when the first position and the second position coincide; a trajectory recognition unit that extracts a first point cloud corresponding to the trajectory as a plurality of points whose distances are measured by the distance sensor; Equipped with The position calculation unit is a velocity calculation device that calculates the first position and the second position based on an orbital plane that is a plane including the first point group.

10. an object recognition unit that extracts a second point cloud corresponding to the object at the first position and the second position as the plurality of points to which distances are measured by the distance sensor; 10. The velocity calculation device according to claim 9, wherein the position calculation unit classifies the second point group by distance and calculates the first distance and the second position by performing coordinate system transformation using the orbital plane as a reference.

11. the distance sensor measures distances on at least three planes that intersect with the direction of movement of the moving object; 11. The velocity calculation device according to claim 10, wherein the trajectory recognition unit extracts the first point cloud from measurement results on a surface at one distance among three distances, and extracts the second point cloud from measurement results on a surface at a distance other than the one distance among at least three distances.

12. 11. The velocity calculation device according to claim 9, wherein the plurality of points are obtained from a distance sensor attached to the side of the vehicle relative to a vertical center line on a plane intersecting the direction of movement of the moving body.

13. measuring a distance to an object, and determining a first position, which is the position of the object at a location a first distance away from the distance sensor and based on the trajectory, and a second position, which is the position of the object at a location a second distance away from the distance sensor and based on the trajectory, based on the measurement result of a distance sensor installed on a moving body moving on a trajectory; calculating a velocity of the moving object based on a difference between the first distance and the second distance and a difference between times when the first position and the second position coincide with each other; A velocity calculation method in which the position of the object continuously deviates as the moving body moves.

14. a velocity calculation device that calculates the velocity of a moving object moving on a trajectory; a control device that controls the movement of the moving body based on the calculated speed; Equipped with The velocity calculation device a position calculation unit that measures a distance to an object and, based on a measurement result of a distance sensor installed on the moving body, calculates a first position, which is a position of the object at a location separated by a first distance from the distance sensor and based on the trajectory, and a second position, which is a position of the object at a location separated by a second distance from the distance sensor and based on the trajectory; a speed calculation unit that calculates a speed of the moving object based on a difference between the first distance and the second distance and a difference between a time when the first position and the second position coincide; Equipped with A mobile object control system in which the position of the object continuously shifts as the mobile object moves.

Images