JP2008180551A - Position display system, position display device, and map-matching method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform map-matching of a position of a moving body such as a train on which a terminal device having a GPS positioning means is installed, correctly on a traveling link. <P>SOLUTION: A position display system 10 includes a network database 38 constituted of nodes and links connecting each node, receives positioning data from each terminal device 20, and extracts links on the periphery of a positioning position from the network database 38, to enable positioning position to be map-matched on some link. The position display system 10 includes a link extraction means 35 for extracting links on the periphery of the positioning position based on positioning data received from the terminal device 20, a positioning vector calculation means 36 for calculating a positioning vector from the positioning data, and a matching link determination means 37. The matching link determination means 37 determines a link having a direction most similar to the direction of the positioning vector as a matching link based on the direction of the positioning vector, and displays the position of the terminal device 20. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a position display system that measures the current position by GPS positioning means, maps the current position to links constituting network data, and displays the current position on the link. A position display system and a position for displaying the current position by map-matching the current position to a link whose direction is close to the traveling direction based on the direction and the traveling direction information included in the current position data measured by the GPS positioning means The present invention relates to a display device and a map matching method.

  2. Description of the Related Art Conventionally, a current position display system and a map display system are known in which a current position of a moving body is measured by GPS positioning means and the current position of the moving body is displayed on a map. A navigation system has been put to practical use as such a system. As a navigation system, a vehicle-mounted navigation system mounted on a car, a navigation system for pedestrians who move using walking and transportation, and the like are known. A system for displaying a map of the vicinity based on the current position is also known. Recently, a communication type system that uses a portable terminal device such as a mobile phone and downloads a guide route or a map from a predetermined information distribution server, a route search server, or the like is widely used as these systems.

  The navigation device comprises map data and road network data for route search, searches for the optimum route from the departure point to the destination by referring to the road network data using the desired departure point and destination as route search conditions, and maps The optimum route is displayed as a guidance route on the top, and the route to the destination is guided. In addition to positioning the current position of the navigation device by satellite navigation using a GPS receiver, in-vehicle navigation devices, positioning by autonomous navigation based on the output of various sensors that detect vehicle movement, such as vehicle speed sensors and steering angle sensors. To do. The current position detected by these positioning means is displayed on the map as a current position mark so that the movement of the navigation device can be confirmed on the map every moment.

  The system for grasping the route and the position of the moving body on the route is used not only for the navigation system and the map display system as described above but also for a vehicle operation management system in public transportation such as a railroad or a bus. The map data in the map information providing system and the navigation system is composed of unit map data (mesh map) divided into meshes at predetermined latitude and longitude intervals.

  Road network data used for route search in a navigation system or the like is configured as follows. That is, the road (route) of the map data is the node, the position of the inflection point is the node, the route connecting each node is the link, and the cost information (distance and required time) of all the links is included. The route search means refers to this road network data and sequentially searches for a link from the departure node to the destination node, and traces the node and the link with the smallest cost information of the link as a guide route. Can guide the shortest route. As such a route search method, a method called label determination method or Dijkstra method is used.

  In general, GPS positioning is used for position measurement of a moving object. GPS positioning uses GPS (Global Positioning System), receives GPS signals transmitted from a plurality of GPS satellites orbiting the earth with a GPS antenna, and receives the GPS signals. The position is specified by analyzing the satellite position and clock information included. At least four GPS satellites are required. The single positioning accuracy of GPS is generally over 10 m, but it is improved to 5 m or less by adopting DGPS (Differential GPS).

  It is well known that the current position by the GPS positioning means includes a calculation error in the processing of GPS satellite signals. In general, the single positioning accuracy of GPS is generally over 10 m, and the position (latitude / longitude) measured by the GPS positioning means may deviate from the road. The matching process is a process for correcting a deviation from the road due to this error. Normally, it is a process that extracts the road closest to the current position (positioned latitude / longitude), and draws a perpendicular to the road from the current position, and corrects the intersection with the road as the current position (corrected latitude / longitude). . Such a processing method is called a projection method, and a method for performing the above processing using road data on a map is called map matching.

  FIG. 9 is a schematic diagram for explaining a map matching method by this projection method. When the current position PP (latitude X / longitude Y) measured by the GPS positioning means and there are two road links LK1 and LK2 as links of the surrounding roads, each road link LK1 from the current position PP Vertical lines are dropped on LK2, and the lengths L1 and L2 of the vertical lines are obtained with the intersections being P1 and P2. Then, the lengths L1 and L2 of the perpendicular lines are compared, and in the case of FIG. 9, the positioning error is corrected as the current position PM matching the intersection P2 of the road link LK2 in the case of FIG.

  Such a matching method exists in the vicinity of the current position PP when the current position PP measured by GPS positioning deviates from the road link on the assumption that the automobile is traveling on the road. It is based on the idea that it is reasonable to estimate that the closest current link among road links, that is, the road link with the shortest perpendicular line, has the correct current position.

  However, in reality, the positioning error in GPS positioning is not constant, and the error may vary depending on various factors. For this reason, there is a first problem that an error occurs that the car is not actually traveling on the road link matched by the projection method as described above and is traveling on another road link. . In addition, according to this projection method, since the intersection of the perpendicular line and the road link taken as the road link is used as the matching position, the distance component in the traveling direction existing at the current GPS position is ignored, and the matching position is shifted. There was a second problem of having.

  As a technique for solving the second problem in map matching by the above-described projection method, for example, a map matching method disclosed in the following Patent Document 1 (Japanese Patent Laid-Open No. 9-5096) is known. The map matching method disclosed in Patent Document 1 monitors whether or not the traveling direction has changed by a predetermined angle or more, and calculates and stores a distance Δx from the GPS detection position P1 ′ to the map matching road RT1. When the traveling direction changes, the GPS detection position P2 ′ is corrected using the distance Δx stored before the traveling direction changes (P2 ′ → P2 ″), and map matching is performed based on the corrected position. The vehicle mark is displayed at the point Q.

  In other words, this map matching method corrects the matching position on the road to be matched using the distance of the traveling direction component at the current position obtained by GPS positioning. The error from the matching position is reduced.

Japanese Patent Laid-Open No. 9-5096 (FIG. 1)

  However, according to the map matching method disclosed in Patent Document 1, the second problem described above can be solved, but the car is not actually traveling on the matched road link, The first problem that an error of traveling on another road link occurs cannot be solved.

  In the railway operation management system, the route of each train is determined based on the operation timetable, so the current position can be measured and matched to the planned route, but the train operation is delayed. In some cases, especially when there is a branch point, it is necessary to determine the current position of each train and map it to network data to determine whether the train is operating correctly on the correct route. .

  In order to solve the above-mentioned problems of the present application, the current position of the link is close to the direction of travel and the direction is based on the direction of the link and the direction of travel information included in the current position data measured by the GPS positioning means. If the present position is displayed by map matching, the above problem can be solved and the present invention has been completed.

  That is, the present invention has an object to solve the above-mentioned problems, and the current position is measured by the GPS positioning means, and the current position is map-matched to the link constituting the network data, and the current position is displayed on the link. It is an object of the present invention to provide a position display system, a position display device, and a map matching method capable of correctly performing map matching on a running link.

In order to solve the above-mentioned problem, the invention according to claim 1 of the present application is
A network database composed of nodes and links connecting the nodes, receiving positioning data from each terminal device, extracting links around the positioning position from the network database, and adding the positioning position to any link In a position display system that displays the position of the terminal device on a network by map matching
The position display system includes a link extraction unit that extracts a link around a positioning position based on positioning data received from the terminal device, a positioning vector calculation unit that calculates a positioning vector from the positioning data, and a matching link determination unit. With
The matching link determining means determines a link having a direction closest to the direction of the positioning vector based on the direction of the positioning vector as a matching link, and matches the position of the terminal device on the link. To do.

The invention according to claim 2 of the present application is the position display system according to claim 1,
The matching link determining means obtains a first intersection group with each link by lowering a perpendicular line perpendicular to a positioning vector to each link extracted by the link extraction means from the positioning position, and then each intersection of the first intersection group. A perpendicular line perpendicular to the corresponding link is set as the positioning vector, a second intersection point group with the positioning vector is obtained, a distance between the positioning position and each intersection point of the second intersection point group is calculated, and positioning is performed based on the distance. A link having a direction closest to the vector direction is determined as a matching link.

The invention according to claim 3 of the present application is the position display system according to claim 1,
The data stored in the network database is railway route network data, the terminal device is a train that operates on the route network, and links around the positioning position are based on the positioning data received from the terminal device. The operation management server includes link extracting means for extracting, positioning vector calculating means for calculating a positioning vector from the positioning data, and matching link determining means, and displaying the position of each terminal device on the operation management server. Features.

The invention according to claim 4 of the present application is
A network database composed of nodes and links connecting the nodes, receiving positioning data from each terminal device, extracting links around the positioning position from the network database, and adding the positioning position to any link In the position display device that displays the position of the terminal device on the network by map matching
The position display device includes a link extraction unit that extracts a link around a positioning position based on the positioning data received from the terminal device, a positioning vector calculation unit that calculates a positioning vector from the positioning data, and a matching link determination unit. With
The matching link determining means determines a link having a direction closest to the direction of the positioning vector based on the direction of the positioning vector as a matching link, and matches the position of the terminal device on the link. To do.

The invention according to claim 5 of the present application is the position display device according to claim 4,
The matching link determining means obtains a first intersection group with each link by lowering a perpendicular line perpendicular to a positioning vector to each link extracted by the link extraction means from the positioning position, and then each intersection of the first intersection group. A perpendicular line perpendicular to the corresponding link is set as the positioning vector, a second intersection point group with the positioning vector is obtained, a distance between the positioning position and each intersection point of the second intersection point group is calculated, and positioning is performed based on the distance. A link having a direction closest to the vector direction is determined as a matching link.

The invention according to claim 6 of the present application is the position display device according to claim 4,
The data stored in the network database is railway route network data, the terminal device is a train that operates on the route network, and links around the positioning position are based on the positioning data received from the terminal device. The operation management server includes link extracting means for extracting, positioning vector calculating means for calculating a positioning vector from the positioning data, and matching link determining means, and displaying the position of each terminal device on the operation management server. Features.

The invention according to claim 7 of the present application is
A network database composed of nodes and links connecting the nodes, receiving positioning data from each terminal device, extracting links around the positioning position from the network database, and adding the positioning position to any link In the map matching method using the position display system for displaying the position of the terminal device on the network by map matching
The position display system includes a link extraction unit that extracts a link around a positioning position based on positioning data received from the terminal device, a positioning vector calculation unit that calculates a positioning vector from the positioning data, and a matching link determination unit. With
The matching link determining means includes a matching link determining step for determining, as a matching link, a link having a direction closest to the direction of the positioning vector based on the direction of the positioning vector, and the position of the terminal device on the link It is characterized by matching.

The invention according to claim 8 of the present application is the map matching method according to claim 7,
The matching link determining step obtains a first intersection point group with each link by dropping a perpendicular line perpendicular to a positioning vector to each link extracted by the link extraction means from the positioning position, and then each intersection point of the first intersection point group A perpendicular line perpendicular to the corresponding link is set as the positioning vector, a second intersection point group with the positioning vector is obtained, a distance between the positioning position and each intersection point of the second intersection point group is calculated, and positioning is performed based on the distance. It includes a process of determining a link having a direction closest to the vector direction as a matching link.

  In the invention according to claim 1, the position display system includes a link extraction unit that extracts a link around the positioning position based on the positioning data received from the terminal device, and a positioning vector calculation unit that calculates a positioning vector from the positioning data. Matching link determining means, and the matching link determining means determines a link having a direction closest to the direction of the positioning vector as a matching link based on the direction of the positioning vector, and determines the position of the terminal device on the link. To match.

  According to such a configuration, the positioning vector at the positioning position is calculated from the current position data (latitude, longitude, speed, direction) measured by the GPS receiving means, and the vicinity of the positioning position (predetermined distance range). The link to be matched is extracted, and the direction (direction) of the positioning vector is compared with the direction (direction) of each link, and the link having the direction closest to the direction of the positioning vector is determined as the map matching link. Therefore, it becomes possible to map-match the positioning position to the correct link.

  According to a second aspect of the present invention, in the position display system according to the first aspect, the matching link determining means takes down the perpendicular perpendicular to the positioning vector to each link extracted by the link extracting means from the positioning position. The first intersection point group is obtained, and then a perpendicular line perpendicular to the corresponding link is established from each intersection point of the first intersection point group to obtain the second intersection point group with the positioning vector, and the positioning position and the second intersection point are obtained. A distance from each intersection of the group is calculated, and a link having a direction closest to the direction of the positioning vector is determined as a matching link based on the distance.

  According to such a configuration, the matching link determination unit performs map matching on the link having the direction closest to the direction of the positioning vector by comparing the direction (direction) of the positioning vector with the direction (direction) of each link. It can be determined as a link, and the positioning position can be map-matched to the correct link.

  According to a third aspect of the present invention, in the position display system according to the first aspect, the data stored in the network database is data of a railway route network, and the terminal device is a train operating on the route network. A link extraction unit that extracts links around the positioning position based on the positioning data received from the terminal device, a positioning vector calculation unit that calculates a positioning vector from the positioning data, and a matching link determination unit. A server is provided, and the position of each terminal device is displayed on the operation management server.

  According to such a configuration, the operation management server can correctly display the position of each train operating on the route on the network. In particular, it becomes possible to correctly grasp the position of each train around the branch point where the route branches.

  Moreover, in the invention concerning Claim 4-Claim 6, the position display apparatus which comprises the position display system concerning Claim 1-Claim 3 can be provided, respectively, According to Claim 7 and Claim 8. In the invention, it is possible to provide a map matching method for realizing the position display system according to claims 1 and 2, respectively.

  Hereinafter, specific examples of the present invention will be described in detail with reference to examples and drawings. However, the embodiment shown below exemplifies a position display system for embodying the technical idea of the present invention, and is not intended to specify the present invention as the position display system of this embodiment. However, the present invention can be equally applied to the position display systems of other embodiments included in the scope of claims.

  FIG. 1 is a block diagram showing a configuration of a position display system 10 according to an embodiment of the present invention. The position display system 10 according to the present embodiment is, for example, a railway operation management system, and includes a terminal device 20 installed in each train as a moving body and an operation management server 30. The terminal device 20 includes a control unit 21, a GPS reception unit 22, and a communication unit 23, and the GPS reception unit 22 measures the current position of the train at a predetermined time interval, and the train current position data is obtained via the communication unit 23. It transmits to the operation management server 30.

  The operation management server 30 includes a control unit 31, a communication unit 32, a display unit 33, a map database 34, a link extraction unit 35, a positioning vector calculation unit 36, a matching link determination unit 37, and a network database 38.

  In the map database 34, map data such as roads, railway lines, prominent landmarks, and terrain are accumulated, and a map image can be displayed on the display means 33. This map data is composed of unit map data divided in a mesh shape with a predetermined latitude and longitude, and a map image of a necessary range can be read from the map database 34 and a map image can be displayed on the display means 33.

  The network database stores data similar to network data for route search in a normal navigation system or the like, and in this embodiment, railway route data is stored. In general, network data for route search includes, for example, nodes, inflection points, and station positions on roads and railway lines as nodes, routes connecting each node as links, and cost information (distance and required) for all links. Time) as a database. In route search, referring to this network database, a link from the departure node to the destination node is sequentially searched, and the shortest route is obtained by using the link having the smallest cost information of the link and the link as the guide route. To be asked. As such a route search method, a method called label determination method or Dijkstra method is used.

  In network data indicating routes of public transportation such as railways, individual trains and buses operating between each node are treated as links based on the data in the operation timetable, and the link cost is based on the scheduled operation time. Is set. In addition, although the network data of such a structure is needed in the server which performs route search, when aiming at train operation management as in this embodiment, the data structure showing only the geographical positional relationship of the railway line In this case, it is sufficient that the node and link data include geographical location information.

  That is, the node is data in which the position is specified by latitude and longitude, and the link is data represented by vector data having the positions of the nodes at both ends and the length and direction between the nodes. This network data is read from the network database 38, can be displayed on the display means 33, and the railway line to be managed can be displayed.

  The operation management server 30 receives the current position of the train operating on each route from the terminal device 20 and displays the train position superimposed on the network data displayed on the display means 33, thereby moving at predetermined time intervals. You can monitor the current location of all trains that do. At this time, since there is an error in the data of the current position received from each terminal device 20, the map matching method in a general navigation system or the like is applied to match the network data to correct the display position of each train.

  When the map matching process is performed using the conventional projection method shown in FIG. 9, the result is as shown in FIG. That is, as shown in FIG. 2, assuming that the network is configured as a route R1, a route R2, a route R3, a route R4, and the positions measured by the terminal device 20 in each positioning tamming are P1 to Pn to Pm. A perpendicular line is dropped on the route R1 or the like within a predetermined range from the positioning position, and the intersection points PP1 to PP2 to PPn to PPm are displayed as the position of the terminal device 20.

  As shown in FIG. 2, at the positioning position Pn, the length of the perpendicular drawn on the route R5 is shorter than the length of the perpendicular drawn on the route R4, and the intersection PPn of the perpendicular drawn on the route R4 is displayed as the current position. However, when the train actually travels on the route R4, the display position must originally be on the route R4, which is a matching error. If the train further travels along the route R4, the positioning position becomes Pn + 2, and the length of the perpendicular dropped on the route R4 becomes shorter than the length of the perpendicular dropped on the route R5, the intersection PPn + 2 of the perpendicular drawn on the route R4 is now It will be displayed as a position and will be matched on the correct route.

  In the present invention, the operation management server 30 calculates a positioning vector at each positioning point based on the position data received from the terminal device 20. A general GPS receiver receives a GPS signal from a GPS satellite and calculates position information by latitude and longitude, but originally calculates the moving speed and moving direction of the terminal device at the positioning point from the GPS satellite signal. Can do. Therefore, the operation management server 30 calculates a positioning vector together with the position at the positioning point.

  In addition, the link extraction unit 35 extracts a link in a predetermined range and a link to be matched from the network database 38 based on the positioning position received from the terminal device 20. The matching link determining unit 37 then determines the direction of the positioning vector based on the positioning vector calculated by the positioning vector calculating unit 36, that is, the direction of the vector at the positioning position, and the direction of the extracted link, that is, the matching target link. Are compared, and a link having a direction close to the direction of the positioning vector is determined as a link to be matched.

  In this way, if you calculate the positioning vector at the positioning point and map-match the positioning position to the link that has a direction close to that direction, it will be correct because it will be map-matched to the link along the direction that the train is actually traveling The position can be corrected and displayed on the route. The matching position may be an intersection of perpendicular lines drawn on the link to be matched by the projection method, or may be a position that takes into account the distance component in the traveling direction as in Patent Document 1.

  3 and 4 are schematic diagrams for explaining the concept of matching processing using the map matching method according to the embodiment of the present invention, and FIG. 3 is a schematic diagram showing matching results based on an example of positioning data. FIG. 4 is a schematic diagram showing a matching result based on another example of positioning data. In FIG. 3, for the sake of easy understanding, a route having the same configuration as the network data shown in FIG. 2 is used, and the same reference numerals are assigned to the same elements as those in FIG.

  As shown in FIG. 3, it is assumed that the network has a configuration such as a route R1, a route R2, a route R3, and a route R4, and the positions measured by the terminal device 20 in each positioning tamming are P1 to Pn to Pm. At each positioning position, the arrows in the figure indicate the respective positioning vectors. As shown in FIG. 3, the direction of the positioning vector at the positioning point Pn is the direction of the arrow. The link extraction means 35 extracts a route R4 and a route R5 as links in a predetermined range around the positioning point Pn, that is, links (routes) to be matched.

  Here, the matching link determination means 37 compares the direction of the route R4 (link), the direction of the route R5 (link), and the direction of the positioning vector, and matches the link whose link direction is closer to the direction of the positioning vector. Determine the link to be used. In FIG. 3, since the direction of the route R4 is closer to the direction of the positioning vector than the direction of the route R5, the route R4 is determined as the matching link.

  The same applies when the positioning result as shown in FIG. 4 is obtained. This positioning result is the figure using the same positioning result as the matching example by the projection method shown in FIG. In FIG. 4, since the direction of the route R4 is closer to the direction of the positioning vector than the direction of the route R5, the route R4 is determined as the matching link. In the matching result shown in FIG. 9, the positioning position Pn near the branch point between the route R4 and the route R5 is matched with the route R5, and the positioning position is advanced and matched with the route R4 as the movement continues. In FIG. 4, even at the positioning position Pn near the branch point between the route R4 and the route R5, the route is matched with the route R4 whose direction is close to the positioning vector based on the direction of the link (the route R4 and the route R5). .

  In this way, the positioning vector at the positioning position is calculated from the data (latitude, longitude, speed, direction) of the current position measured by the GPS receiving means, and matching is performed around the positioning position (predetermined distance range). By extracting the power links and comparing the direction (direction) of the positioning vector with the direction (direction) of each link, the link having the direction closest to the direction of the positioning vector is determined as the map matching link. To be able to match.

  Next, this matching link determination method will be described in more detail. 5 to 7 are diagrams for explaining the processing procedure of the matching link determination unit 37, FIG. 6 is a partially enlarged view of FIG. 5, and FIG. 7 is a partially enlarged view of FIG. First, as shown in FIG. 5, the point P0 is the current position (X0, Y0) measured, and the surrounding network data branches at the node L1 to the link L13 to the node N1 to the node 13 and the node N1 to branch to the node N23. Assume that there are links L22 to L23 that lead to.

  If the positioning vector at the point P0 calculated by the positioning vector calculation means 36 is VP0, the link extraction means 35 extracts the links L12 to L13 and the links L22 to L23 around the current position P0 as links to be matched. The matching link determining means 37 first drops a perpendicular line (a line perpendicular to the positioning vector VP0) from the positioning position P0 (X0, Y0) to the link L12 and the link L22, and sets the intersection point of the link L12 to PP1 (X1, Y1). A first intersection point group having the intersection point with L22 as PP2 (X2, Y2) is obtained.

  FIG. 6 shows an enlarged view of this part. As shown in FIG. 6, the matching link determining means 37 further forms a perpendicular line (perpendicular perpendicular to the link L12 and link L2) from the intersection points PP1 and PP2 with each link to the positioning vector VP0. Alternatively, a second intersection point group having intersections with the extension lines as P1 (DX1, DY1) and P2 (DX2, DY2) is obtained, and lengths L1 and L2 of the respective perpendiculars are obtained.

  FIG. 7 is an enlarged view of the portion of FIG. Next, as shown in FIG. 7, the matching link determination unit 37 includes intersections P <b> 1 and P <b> 2 (respective intersections of the second intersection group) between the perpendicular line established from each link and the positioning vector VP <b> 0 (or an extension thereof). The distances DL1 and DL2 with the positioning point P0 are obtained. Then, the ratio between the length L1 of the vertical line and the distance DL1 (DL1 / L1 absolute value) and the ratio between the length L2 of the vertical line and the distance DL2 (absolute value of DL2 / L2) are calculated, and the positioning vector VP0 A link having a direction close to the direction is determined as a matching link.

That is,
When (absolute value of DL1 / L1) <(absolute value of DL2 / L2), PP1 (X1, Y1) is a matching point (link L12 is a matching link).
When (absolute value of DL1 / L1)> (absolute value of DL2 / L2), PP2 (X2, Y2) is a matching point (link L22 is a matching link).

  When (absolute value of DL1 / L1) = (absolute value of DL2 / L2), it means that the direction of the positioning vector is equal to the direction of both links. In this case, the normal projection method is used. In consideration of this, the link with the shorter perpendicular (link closer to the positioning vector) may be provisionally determined as the matching link.

  Such a link is a link configuration found in a double-track section in a railway network. In the railway network, since it is known from the operation timetable if the vehicle can be identified as to which route each vehicle travels, the planned travel route may be determined as a matching link in consideration of this.

  Further, as a method for determining the link having the direction closest to the direction of the positioning vector, other procedures can be adopted regardless of the procedure described above. That is, since the positioning vector VP0 is calculated based on the GPS positioning data, its direction (direction) can be expressed by an absolute direction. If the direction (direction) of each link constituting the network data is recorded in the absolute direction, the absolute direction of each link extracted as a link to be matched with the absolute direction of the positioning vector VP0 is directly compared and calculated. A link having an absolute direction closest to the absolute direction of the vector can also be determined as a matching link.

  Next, a map matching procedure according to the embodiment of the present invention will be described with reference to the flowchart shown in FIG. First, the operation management server 30 receives the positioning information at the point P0 of the terminal device 20 in the process of step S11. The positioning vector calculation means 36 calculates a positioning vector at the point P0 based on the positioning information received from the terminal device 20 in the process of step S12.

  Next, in the process of step S13, the link extraction means 35 refers to the network database 38 and extracts the periphery of the point P0 (links within a predetermined distance range (see FIG. 5). Next, the matching link determination means 37 The matching link is determined by the following procedure.

  First, in the process of step S14, a perpendicular to the positioning vector is taken from the position P0 of the positioning vector, and intersection points PP1, PP2,. Further, the lengths L1, L2,... From the point P0 to the intersections PP1, PP2,... Are obtained in the process of step S15 (see FIG. 5).

  Next, in the process of step S16, a perpendicular is drawn from each intersection PP1, PP2,... To the positioning vector, and intersections P1, P2,. In the process of step S17, the distances DL1, DL2,... Between the points P0 and P1 and the points P0 and P2.

In step S18, the matching link determination unit 37 performs DL1 / L1,
DL2 / L2... Is calculated (see FIG. 7), and DL1 / L1 and DL2 / L2 are compared in the process of step S19 to determine a matching link.
As a result of comparison as shown in FIG.
When (absolute value of DL1 / L1) <(absolute value of DL2 / L2), PP1 (X1, Y1) is a matching point (link L12 is a matching link).
When (absolute value of DL1 / L1)> (absolute value of DL2 / L2), PP2 (X2, Y2) is a matching point (link L22 is a matching link).

  By such processing, map matching can be performed with a link having a direction closest to the direction of the positioning vector. Since the direction of the positioning vector at the positioning point indicates the direction of movement of the terminal device 20, the position of the terminal device 20 can be displayed on the correct link if matching is performed on a link in a direction close to this direction. It becomes like this.

  Although the above embodiment has been described using a train operation management system as a specific example, the map matching procedure according to the present invention can also be applied to a general navigation system.

It is a block diagram which shows the structure of the position display system concerning the Example of this invention. It is a schematic diagram which shows the example which carried out the map matching of the position of the moving body by the projection method. It is a schematic diagram for demonstrating the concept of the matching process using the map matching method concerning the Example of this invention. It is another schematic diagram for demonstrating the concept of the matching process using the map matching method concerning the Example of this invention. It is a network schematic diagram for demonstrating the procedure of the map matching concerning the Example of this invention. It is the elements on larger scale of the network schematic diagram of FIG. It is the elements on larger scale of the network schematic diagram of FIG. It is a flowchart which shows the procedure of the map matching concerning the Example of this invention. It is a schematic diagram for demonstrating the general map matching method.

Explanation of symbols

10 .... Position display system 20 ... Terminal device 21 ... Control means 22 ... GPS reception means 23 ... Communication means 30 ... Operation management server 31 ... Control means 32 ... Communication means 33 ... Display means 34 ... Map database 35 ... Link extraction means 36 ... Positioning vector calculation means 37 ... Matching link determination means ( Matching means)
38 ... Network database

Claims (8)

A network database composed of nodes and links connecting the nodes, receiving positioning data from each terminal device, extracting links around the positioning position from the network database, and adding the positioning position to any link In a position display system that displays the position of the terminal device on a network by map matching
The position display system includes a link extraction unit that extracts a link around a positioning position based on positioning data received from the terminal device, a positioning vector calculation unit that calculates a positioning vector from the positioning data, and a matching link determination unit. With
The matching link determining means determines a link having a direction closest to the direction of the positioning vector based on the direction of the positioning vector as a matching link, and matches the position of the terminal device on the link. Position display system.   The matching link determining means obtains a first intersection group with each link by lowering a perpendicular line perpendicular to a positioning vector to each link extracted by the link extraction means from the positioning position, and then each intersection of the first intersection group. A perpendicular line perpendicular to the corresponding link is set as the positioning vector, a second intersection point group with the positioning vector is obtained, a distance between the positioning position and each intersection point of the second intersection point group is calculated, and positioning is performed based on the distance. The position display system according to claim 1, wherein a link having a direction closest to a vector direction is determined as a matching link.   The data stored in the network database is railway route network data, the terminal device is a train that operates on the route network, and links around the positioning position are based on the positioning data received from the terminal device. The operation management server includes link extracting means for extracting, positioning vector calculating means for calculating a positioning vector from the positioning data, and matching link determining means, and displaying the position of each terminal device on the operation management server. The position display system according to claim 1. A network database composed of nodes and links connecting the nodes, receiving positioning data from each terminal device, extracting links around the positioning position from the network database, and adding the positioning position to any link In the position display device that displays the position of the terminal device on the network by map matching
The position display device includes a link extraction unit that extracts a link around a positioning position based on the positioning data received from the terminal device, a positioning vector calculation unit that calculates a positioning vector from the positioning data, and a matching link determination unit. With
The matching link determining means determines a link having a direction closest to the direction of the positioning vector based on the direction of the positioning vector as a matching link, and matches the position of the terminal device on the link. Position display device.   The matching link determining means obtains a first intersection point group with each link by dropping a perpendicular line perpendicular to a positioning vector to each link extracted by the link extracting means, and then each intersection point of the first intersection point group. A perpendicular line perpendicular to the corresponding link is set as the positioning vector, a second intersection point group with the positioning vector is obtained, a distance between the positioning position and each intersection point of the second intersection point group is calculated, and positioning is performed based on the distance. 5. The position display device according to claim 4, wherein a link having a direction closest to the vector direction is determined as a matching link.   The data stored in the network database is railway route network data, the terminal device is a train that operates on the route network, and links around the positioning position are based on the positioning data received from the terminal device. The operation management server includes link extracting means for extracting, positioning vector calculating means for calculating a positioning vector from the positioning data, and matching link determining means, and displaying the position of each terminal device on the operation management server. The position display device according to claim 4, wherein: A network database composed of nodes and links connecting the nodes, receiving positioning data from each terminal device, extracting links around the positioning position from the network database, and adding the positioning position to any link In the map matching method using the position display system for displaying the position of the terminal device on the network by map matching
The position display system includes a link extraction unit that extracts a link around a positioning position based on positioning data received from the terminal device, a positioning vector calculation unit that calculates a positioning vector from the positioning data, and a matching link determination unit. With
The matching link determining means includes a matching link determining step for determining, as a matching link, a link having a direction closest to the direction of the positioning vector based on the direction of the positioning vector, and the position of the terminal device on the link A map matching method characterized by matching to a map.   The matching link determining step obtains a first intersection point group with each link by dropping a perpendicular line perpendicular to a positioning vector to each link extracted by the link extraction means from the positioning position, and then each intersection point of the first intersection point group A perpendicular line perpendicular to the corresponding link is set as the positioning vector, a second intersection point group with the positioning vector is obtained, a distance between the positioning position and each intersection point of the second intersection point group is calculated, and positioning is performed based on the distance. The map matching method according to claim 7, further comprising: determining a link having a direction closest to the vector direction as a matching link.

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