Speed calculation device, speed calculation method, and movable body 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 train 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 the ground speed from a moving object such as a railway vehicle, and in many cases the ground speed is calculated by integrating the 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] JP 2014-220858 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, when wheel rotation pulses are used, if phenomena such as slippage or sliding occur, accurate speed cannot be obtained. On the other hand, there are also methods such as using the rotation pulses of multiple wheels to compensate for slippage, or using free wheels only for speed measurement, but these methods have the problem of being very costly. Also, Doppler speedometers and spatial filter speedometers using laser light or microwaves are known as existing technologies for measuring speed without contact. However, these Doppler speedometers and spatial filter speedometers have the problem that when the distance between the moving body and the object irradiated with the laser light varies depending on the timing of the irradiation of the laser light or microwave, the accurate speed cannot be calculated due to the range of the variation in the distance. An object of the present invention is to provide a velocity calculation device and a velocity calculation method that are capable of measuring the velocity of a moving object more accurately compared to a case not having the configuration of the present invention. [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 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, based on the measurement results of the distance sensor installed on a moving object moving on a trajectory, 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 time at which the first position and the second position coincide.

[0007] Here, the position of the object may be continuously shifted in accordance with the movement of the moving body, in which case the number of measurement points for measuring the distance may be increased. The object whose position is continuously shifted may be a railway overhead line, which is less susceptible to environmental changes than other ground facilities. Furthermore, the overhead line may be at least one of a contact wire and a catenary wire, in which case the speed can be measured more continuously and a more accurate speed can be calculated even if the speed of the vehicle changes. Furthermore, the position calculation unit can be configured to obtain the first position and the second position that change as the contact wire shifts in the left and right direction in response to the movement of the moving body. In this case, the speed of the vehicle can be continuously measured by utilizing the left and right shift of the contact wire. Furthermore, the position calculation unit can determine the first position and the second position that change as the catenary wire shifts in the vertical direction in response to the movement of the train. In this case, the speed of the vehicle can be continuously measured by utilizing the vertical shift of the catenary wire. In addition, there may be a plurality of tracks, and the tracks and overhead lines for determining the first and second positions may be different from those used when the moving body 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 trajectory of each of the first position and the second position, and the speed calculation unit can calculate the speed of the moving object based on the trajectory. In this case, it is possible to reduce distance measurement errors. The device may further include a trajectory matching unit that obtains a time difference by matching the trajectories of the first position and the second position, whereby the time difference can be obtained more accurately.

[0009] The device 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 position and the second position based on a trajectory plane that is a plane including the first point group. In this case, the first position and the second position can be measured more accurately. Furthermore, the vehicle 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 a plurality of 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 orbit plane. In this case, the first position and the second position can be measured more accurately. The distance sensor measures distances on a surface at at least three distances that intersect with the moving direction of the moving body, and the trajectory recognition unit extracts a first point cloud from the measurement results on the surface at one of the at least three distances, and extracts a second point cloud from the measurement results on the surface 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 travel of the moving object. In this case, more information on the characteristic points of the object can be captured.

[0010] The present invention also provides a speed calculation method which measures the distance to an object and, based on the measurement results of a distance sensor installed on a moving object moving on a track, determines a first position, which is the position of the object based on the track 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 track at a location a second distance away from the distance sensor, and calculates the speed 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 speed calculation device that calculates the speed of a mobile body moving on a trajectory, and a control device that controls the movement of the mobile body based on the calculated speed, wherein the speed calculation device comprises a position calculation unit that measures a distance to an object and 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 based on the measurement results of a distance sensor installed on the mobile body, 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 speed calculation unit that calculates the speed 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. Effect of the Invention

[0012] According to the present invention, it is possible to provide a velocity calculation device and a velocity calculation method that are capable of measuring the velocity of a moving object more accurately, as compared to a case not equipped with the configuration of the present invention. [Brief description of the drawings]

[0013] [Figure 1] 1 is a conceptual diagram showing an overall configuration of a train control system according to an embodiment of the present invention. [Diagram 2]1 is a cross-sectional view of a vehicle cut along a plane perpendicular to the traveling direction of the vehicle. [Diagram 3] 4 is a flowchart illustrating the operation of the vehicle speed recognition system. [Figure 4] 1(a) and 1(b) are diagrams showing a state in which a contact wire is installed. [Diagram 5] FIG. 2 is a diagram illustrating a rail plane and a coordinate system based on the rail plane. [Figure 6] 4(a) to (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] 13(a) and 13(b) are diagrams illustrating a case where the speed of a vehicle is calculated when a catenary wire is used. [Figure 9] FIG. 13 is a diagram showing a case where the speed of a vehicle is calculated when a catenary wire is used. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. [First embodiment] First, a first embodiment will be described. In the first embodiment, a case will be described in which the speed of a moving object is calculated by utilizing the lateral deviation of a contact wire 103 of a railway overhead line.

[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 in this 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 an electric circuit facility D provided along left and right rails 102, which are an example of a track, to drive an electric motor and the like (not shown). The vehicle 101 then moves on the rails 102 by the driving force of the driven electric motor and 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] Representative components of the electric circuit facility D include the contact wire 103 that contacts the vehicle 101 at the pantograph Pn, the catenary 104 and hanger 105 that suspend 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 line recognition unit 109, a rail surface recognition unit 110, an overhead line position calculation unit 111, overhead line trajectory calculation units 112-1 to 112-N, an overhead 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 line and rail 102 to measure the three-dimensional shape. The sensing unit 108 then transmits data of the three-dimensional shape (measurement data) to the overhead line 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 this 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 above-mentioned measurement data is data (data group) that expresses the three-dimensional shape of the overhead wire or rail 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 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 capture the surface shape of the target in the same way (although the amount of information that can be obtained at one time is smaller 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. Hereinafter, the positional relationship between the vehicle 101, the sensing unit 108, and the overhead lines (the trolley wire 103, the messenger wire 104, the hanger 105, the support 106, and the insulator 107) will be described in detail with reference to FIG. The sensing unit 108 is installed at a location that passes through the contact point between the pantograph Pn and the trolley 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 from the center line C in the vertical direction on a plane that intersects with the moving direction 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 line from an oblique direction. This is because the more information on the characteristic points of the overhead line is captured, the more advantageous it is for the subsequent processing (matching processing described in FIG. 5), and this is to capture as many components of the overhead line 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 trolley wire 103, the hanger 105 and the messenger wire 104 that suspend the trolley wire 103 in the vertical direction will be hidden behind the trolley wire 103 and will not be scanned. In contrast, in this embodiment, the sensing unit 108 is provided at a position shifted from directly under 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. Since the support 106 needs to support all the structures below it, including the catenary 104 and the trolley 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 catenary. This makes it relatively easy to capture its three-dimensional shape with LIDAR. Also, 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 it by scanning with LIDAR. 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 overhead line measurement data (measurement results) 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 an 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 two (a pair of) rail surfaces on the basis of measurement data. Here, the overhead line position calculation unit 111 classifies the overhead line positions by distance. Here, it is assumed that 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 line locus matching unit 113 is an example of a locus matching unit, and matches overhead line loci at a plurality of locations (N locations) calculated by the overhead line locus calculation units 112-1 to 112-N, and calculates the time interval and distance interval 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 interval and the distance interval between the overhead line parts found by the overhead line trajectory matching unit 113 , and transmits it 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 runs between set points (for example, between stations) according to a scheduled time (schedule). In addition to ATO, a signal system (ATP: Automatic Train Protection) that controls the brakes to ensure a safe distance between vehicles is also an example of an application that uses the estimated speed of the vehicle 101.

[0024] Some or all of the functions of the vehicle speed recognition system 100 can be realized by a computer device that operates by cooperation between software and hardware resources. That is, a central processing unit (CPU) (not shown) in a computer provided in the vehicle speed recognition system 100 executes a program that realizes each function, and realizes each function. The program is stored in a 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 is loaded from the auxiliary storage device to a main storage device (random access memory (RAM)) and executed. These functions can also be realized by hardware such as a dedicated circuit.

[0025] <Description of the operation of the 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 deviation of the trolley wire 103 is used to detect the speed.

[0026] 4(a) and (b) are diagrams showing a state in which the trolley wire 103 is installed. As shown in Fig. 4(a)-(b), the vehicle 101 receives high voltage by sliding contact of the contact plate provided on the pantograph Pn with the trolley wire 103, and travels on the left and right rails 102. In order to uniformly wear the contact plate, the contact wire 103 is pulled outward for each utility pole and is installed with a zigzag deviation (left-right deviation) as shown in Fig. 4(b). More specifically, the contact wire 103 is installed so as to deviate in a crossing direction (in this case, the left-right direction of the vehicle 101) about the center line 102m of the left and right rails 102 as the vehicle 101 travels. In other words, the contact wire 103 deviates left and right in response to the movement of the vehicle 101, and the position of the contact wire 103 changes left and right when viewed from the vehicle 101. In this case, the position of the trolley wire 103, as viewed from the vehicle 101, changes regularly in the left-right direction around the center line 102m. 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 passing through the upper surfaces of the left and right rails 102. The X-axis direction, the Y-axis direction, and the Z-axis direction are illustrated 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, that is, to the left. The Z-axis direction is defined as a direction perpendicular to the traveling direction of the vehicle 101, that is, to the upward direction. The position of the trolley wire 103 can be regarded as a 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 a reference.

[0031] 3 again, in step S105, the overhead line locus calculation units 112-1 to 112-N calculate overhead line loci 1 to N, respectively, from each point group classified (1 to N) by distance from the vehicle 101. That is, the overhead line locus calculation units 112-1 to 112-N calculate the locus of positions of distance Yc at positions of the contact wire 103 at N different distances from the vehicle 101 as the overhead line locus 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 pair of the time interval ΔTn and the distance interval ΔDn acquired in step S106 by 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 (c) and FIG. 7 are diagrams for explaining steps S105 to S107 in FIG. 3 in more detail. Of these, Fig. 6(a) is a diagram of the vehicle 101, rail 102, and trolley wire 103 as viewed from above. Also, Figs. 6(b)-(c) are diagrams as viewed from the VIbc direction in Fig. 6(a), that is, diagrams of the vehicle 101, rail 102, and trolley wire 103 as viewed along the Y direction.

[0034] In the above description, in step S105, the overhead line trajectory calculation units 112-1 to 112-N acquire the positions of the contact wire 103 at N distances, 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 the position at the distance Yc between the two overhead line positions.

[0035] The sensing unit 108 is a LIDAR having three two-dimensional scan planes. In Fig. 6(a) to (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 used to measure the trolley wire 103 and calculate the respective distances Yc between the positions of the trolley wire 103 at two different distances.

[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 Fig. 7. Similarly, the position of the point cloud observed on scan plane B fluctuates as shown by curve B. In Fig. 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 the distance is defined as L A , L B In this embodiment, the distance L A is an example of a first distance, and the distance L B is an example of the second distance. Curve A in the graph of FIG. 7 indicates the distance L A It can be understood that the distance L represents the position of the trolley wire 103 at a distance Yc relative to the rail 102, and is the locus of the trolley wire 103. A The position of the object at the distance Yc in is an example of a first position that is a position of the object based on the trajectory. Also, the curve B in the graph of FIG. 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 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, the measurement errors can be reduced and a more accurate trajectory can be obtained. As a result, the distance Yc can be grasped more accurately.

[0038] Then, when the curve B in the graph of FIG. 7 is shifted by a certain time interval ΔTn, it approximately coincides with the curve A. This means that the same position of the contact wire 103 is measured with a shift of the time interval ΔTn. That is, the vehicle 101 at the location shown in FIG. 6(b) measures the position P of the contact wire 103 on the scan plane A. Then, when the time interval ΔTn has elapsed and the vehicle 101 has moved to the location shown in FIG. 6(c), it 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 by matching the curve A with the curve B. That is, 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 set 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 = 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 between the distance (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 position of the distance Yc at the time of the vehicle 101 and the position of the distance L A Position of distance Yc and distance L B The respective loci of the positions of the distance Yc at the above points are obtained, and then the respective loci are matched in 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 in FIG. 3, a first point group corresponding to the rail 102 is extracted as a plurality of points to which the distances are 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 on the line 104 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 obtain a position at a distance L A Position of distance Yc and distance L B It can also be said that the position of the distance Yc at 3, the sensing unit 108 measures distances on surfaces at at least three distances that intersect with the moving direction 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 (scan surface R in this case), and in step S102, it can be said that the rail surface recognition unit 110 extracts a second point cloud from the measurement results on surfaces at other distances other than this one distance (scan surfaces A and B in this case).

[0041] [Second embodiment] Next, a second embodiment will be described. In the second embodiment, the speed of a moving object is calculated by using the vertical deviation of a catenary 104, instead of the horizontal deviation of a contact wire 103, as an overhead line of a railway. When the deviation of the trolley wire 103 in the left-right direction is small or nonexistent, it may be difficult to obtain 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 messenger 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)-(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)-(b) are views of the vehicle 101 and the like viewed from the same direction as in Fig. 6(b)-(c), in which the sensing unit 108 is shown. In this case, the vehicle 101, the rail 102, and the catenary wire 104 are shown as viewed along the Y direction. Then, the 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, similar to the first embodiment. On the other hand, the scan planes A and B measure the messenger wire 104 and measure the vertical (Z-direction) positions of the messenger wire 104 at two different distances with respect 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 is installed so as to shift in the vertical direction (Z direction) as the vehicle 101 travels. Therefore, when viewed from the vehicle 101, the position of the catenary wire 104 changes in the vertical direction. When viewed from the vehicle 101, the position of the catenary wire 104 changes regularly in the vertical direction.

[0044] When the vehicle 101 travels, the positions of the point cloud observed on scan plane A in the direction perpendicular to the traveling direction fluctuate as shown by curve A in the graph of Fig. 9. Similarly, the positions of the point cloud observed on scan plane B fluctuate 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 messenger wire 104.

[0045] As in the first embodiment, the overhead contact line trajectory calculation unit 112 may perform fitting and calculate the trajectory using a known method such as the least squares method. As a result, the distance Zc between the rail plane Hr and the catenary wire 104 can be grasped more accurately.

[0046] The following will be almost the same as the first embodiment, except that the contact wire 103 is replaced with the catenary wire 104 and the distance Yc is replaced with the distance Zc. In other words, 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 that distance is L A , L B 9. Curve A in the graph of FIG. 9 represents the distance L A It represents the distance Zc, which is the position of the catenary 104 with respect to the rail 102 at a distant point, and can be understood as its trajectory. A The position of the distance Zc at the time of the detection is an example of the 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 104 with respect to the rail 102 at a distant point, 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 the curve B in the graph of FIG. 9 is shifted by a certain time interval ΔTn, it approximately matches the curve A. This means that the same position of the catenary 104 is measured with a shift of the time interval ΔTn. That is, the vehicle 101 at the location shown in FIG. 8(a) measures the position P of the catenary 104 on the scan plane A. Then, when the time interval ΔTn has elapsed and the vehicle 101 has advanced to the location shown in FIG. 8(b), it measures the same position P of the catenary 104 on the scan plane B. This time interval ΔTn can be obtained by the catenary trajectory matching unit 113 by matching the curve A with the curve B. That is, the amount of shift when either the curve A or the curve B is shifted in the time direction and matches the other is set 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 using 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 circuit equipment D for power supply deployed above the vehicle 101, so that the speed of the vehicle 101 traveling on the rail 102 can be recognized with high reliability. In addition, in the second embodiment, the three-dimensional shape of the catenary wire 104 is used as the electric circuit equipment D for power supply deployed above the vehicle 101, so that the speed of the vehicle 101 traveling on the rail 102 can be recognized with high reliability. In the present embodiment, compared to the case where the rotation pulse of the wheel is used, the speed is not affected by wheel slippage, skidding, etc., and therefore a more accurate speed can be calculated. Furthermore, compared to the method using a Doppler speedometer using laser light or microwaves or a spatial filter type speedometer, by using the position of the distance Yc or the distance Zc with the rail plane Hr as a reference, even if the distance between the sensing unit 108 and an object such as an overhead line varies, the speed is less affected and a more accurate speed can be calculated. 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, the speed is less affected by vibrations of the vehicle 101, etc. Therefore, in the present embodiment, robust speed detection is possible. In addition, when the contact wire 103 and the catenary wire 104 are used, the system is less susceptible to environmental changes compared to the case where other ground facilities are used. For example, when the electric circuit facility D is used, the system is less susceptible to snowfall. In addition, in this case, there is no need to rely on the Global Positioning System (GPS) or map information.

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

[0050] However, it is preferable that the object is one whose position continuously shifts as the vehicle 101 moves. That is, it is preferable that the object is one whose position continuously shifts and whose position can be continuously measured, such as the trolley wire 103 or the catenary wire 104. In this case, the number of measurement points for measuring the distance increases, which reduces measurement errors and allows the position of the object to be measured more accurately. In addition, even if the speed of the vehicle 101 changes, the speed can be calculated more accurately. In other words, by being able to continuously measure the position, 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, if the hanger 105, the support 106, the insulator 107, etc. are used as the object, these are installed discretely at a predetermined distance apart. Therefore, although the speed of the vehicle 101 can be calculated, when the speed of the vehicle 101 changes, it is not necessarily possible to calculate the speed of the vehicle 101 with good responsiveness. For example, as mentioned above, the supports 106 have the advantage of being large and easy to capture by the sensing unit 108, but because they are erected at intervals of, for example, several hundred meters, if the speed of the vehicle 101 is calculated based on these, it is not necessarily possible to calculate the speed of the vehicle 101 with good responsiveness.

[0051] In the above detailed example, the contact wire 103 and the messenger wire 104 are described as being regularly deviated, but the present invention is not limited to this and they may be irregularly deviated. In the first embodiment, the trolley wire 103 is described as being displaced in the left and right directions about the center line 102m. However, the trolley wire 103 does not have to be displaced about the center line 102m.

[0052] In the above detailed example, the rails 102 and overhead lines 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 the distance may be different from those used when the vehicle 101 is moving. In other words, in a double track section, the adjacent track on which the adjacent vehicle (in this case, an oncoming train) is running and the overhead wires erected on that track may also be used. 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 thereon are used. This can of course be applied to cases such as quadruple tracks, and even triple quadruple tracks.

[0053] <Explanation of speed calculation method> Here, the process performed by the speed recognition system 100 is to measure the distance to an object such as a trolley wire 103 or a catenary wire 104, and to calculate 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 A first position, which is the position of the object relative to the rail 102 at a distant location, is a distance L B A second position, which is the position of the object at a distant location relative to the rail 102, is obtained, and the distance L A and distance L B This can be regarded 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 described in 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 line recognition unit, 110...rail surface recognition unit, 111...overhead line position calculation unit, 112-1 to 112-N...overhead line trajectory calculation unit, 113...overhead line 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 obtains, based on a measurement result of a distance sensor installed on a moving body moving on a track, a first position which is a position of the object at a location separated by a first distance from the distance sensor with respect to the track, and a second position which is a position of the object at a location separated by a second distance from the distance sensor with respect to the track; 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 with each other; Equipped with A velocity calculation device in which the position of the object continuously shifts in accordance with the movement of the moving body.

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

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

4. The speed 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 shifts in the left-right direction in response to movement of the moving body.

5. 4. The speed calculation device according to claim 3, wherein the position calculation unit determines the first position and the second position, which change as the catenary wire shifts in an up-down direction in response to movement of a train.

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

7. A position calculation unit which measures a distance to an object and determines, based on the measurement results of a distance sensor installed on a moving body moving on a trajectory, 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; 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 with each other; a trajectory calculation unit for calculating a trajectory of each 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 obtains the time difference by matching the trajectories of the first position and the second position.

9. A position calculation unit which measures a distance to an object and determines, based on the measurement results of a distance sensor installed on a moving body moving on a trajectory, 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; 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 with each other; 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 determines the first position and the second position based on an orbit plane, which is a plane that includes 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 a plurality of points whose 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 with the orbit plane as a reference.

11. the distance sensor measures distances on at least three planes intersecting a moving direction 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 speed calculation device according to claim 9, wherein the plurality of points are acquired from the distance sensor attached to a side of the vehicle relative to a vertical center line on a plane intersecting a direction of movement of the moving body.

13. measuring a distance to an object, and determining, based on a measurement result of a distance sensor installed on a moving body moving on a track, 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 track, 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 track; calculating 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 with each other; A velocity calculation method in which the position of the object continuously shifts in accordance with the movement of the moving body.

14. A speed calculation device that calculates the speed of a moving object moving on a trajectory; A control device that controls the movement of the moving object based on the calculated speed; Preparation, The speed calculation device is a position calculation unit that measures a distance to an object and obtains, based on a measurement result of a distance sensor installed on the moving body, a first position that is a position of the object at a location a first distance away from the distance sensor and based on the trajectory, and a second position that is a position of the object at a location a second distance away 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 with each other; Equipped with A mobile object control system, wherein the position of the object continuously shifts in accordance with the movement of the mobile object.

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