JP5547106B2 - Route arithmetic unit - Google Patents

Description

  The present invention relates to a route calculation device that searches for a route of a mobile object.

  The route calculation device is included in, for example, an in-vehicle terminal device mounted on a vehicle or a center device arranged in an information distribution center, and calculates a route from a departure place to a destination using digitized map data. Further, the route calculation device provides the calculated route to the user.

  For example, Patent Document 1 discloses a method for calculating a route from a departure place to a destination in a conventional route calculation apparatus. This method divides the map into zones and calculates the cost within the zone before route search. At this time, the cost is calculated for each direction passing through the zone. This direction is, for example, from west to east and from south to north. When searching for a route, (1) a zone that passes from the departure point to the destination is determined using the cost for each direction calculated in advance. Next, (2) a route in the zone is searched for each passing zone. Finally, (3) connecting the routes of the passing zones and determining whether or not the route from the starting point to the destination is established, and if so, outputting the route. If not, repeat steps (1) to (3) until the route from the departure place to the destination is established.

JP 2005-55915 A

  However, according to the method described in Patent Document 1, it is not possible to consider a situation that cannot be assumed at the stage of cost calculation before route search. For example, when information on traffic jams caused by a car accident is acquired, even if it is desired to avoid the traffic jams, the traffic jam information cannot be taken into account if the cost has already been calculated.

(1) In the route calculation device according to claim 1, the map data in which the road link and the mesh data defining the map are associated with each other, and the mesh and at least one adjacent mesh of the mesh are at both ends of the in-mesh minimum cost route. A first boundary node located at the boundary between the start point mesh including the start point of the moving object and the start point adjacent mesh adjacent to the start point mesh based on the mesh cost representing the cost of the minimum cost path in the mesh when each of the nodes is shared Relay mesh acquisition that acquires a plurality of relay meshes included in the minimum cost path between the boundary nodes to the second boundary node located at the boundary between the end point mesh including the end point of the moving object and the end point adjacent mesh adjacent to the end point mesh means, and traffic information acquiring means for acquiring current traffic information, included in the connection minimum cost path between the boundary node In a mesh comprising sections road link, and link cost sections road links, current traffic when information difference between the interval Status cost of the road link based on is not smaller than a predetermined threshold value, the minimum in the new mesh based on the link cost update cost Update the mesh cost to represent the cost of the route, update multiple relay meshes based on the updated mesh cost, and based on the updated multiple relay meshes and the new minimum cost path in the mesh, from the start point to the end point And a predetermined threshold value is a function corresponding to an estimated elapsed time from the start of the moving body to the movement of the section road link. .

  According to the present invention, a user can efficiently execute a route search corresponding to real-time information.

It is a figure which shows the whole structure of the vehicle-mounted terminal device of this invention. It is a figure which shows the structure of map data. It is a figure which shows the example of a maple node. It is a figure which shows the structure of mesh cost data. It is a figure which shows the processing flow for mesh cost data preparation. It is a figure which shows the processing flow of a passage mesh calculation apparatus. It is a figure which shows the example of a passage mesh. It is a figure which shows the example of the candidate maple node by the side of departure. It is a figure which shows the processing flow which determines a candidate maple node. It is a figure which shows the example which carries out route search using mesh cost data. It is a figure which shows the structure of the passage mesh stored in a route search result storage device. It is a figure which shows the processing flow of a route search apparatus. It is a conceptual diagram of a route search process. It is a figure which shows the structure of the route search result stored in a route search result storage device. It is a figure which shows the processing flow of a comparison apparatus. It is a figure which shows the processing flow which determines a re-search mesh. It is a conceptual diagram of the re-search in a route search apparatus. It is a figure which shows the example of a display of a route search result in a display apparatus. It is a figure which shows a route search system. It is a figure which shows the structure of the road link corresponding to mesh cost data.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a path calculation device using the present invention will be described with reference to the drawings.

-First embodiment-
FIG. 1 is a diagram showing an overall configuration of an in-vehicle terminal device 100 according to the first embodiment of the present invention. The in-vehicle terminal device 100 includes a destination input device 110, a vehicle position calculation device 130 of a vehicle on which the in-vehicle terminal device 100 is mounted, map data 140, mesh cost data 150, a passing mesh calculation device 160, a route search device 170, a route. A search result storage device 180, a real-time information acquisition device 190, a comparison device 200, and a display device 220 are included.

  The in-vehicle terminal device 100 and the sensors 120 are connected via an in-vehicle network such as CAN.

  The destination input device 110 receives destination information and route search type information that a user inputs through a user interface such as a remote controller of the in-vehicle terminal device 100. The destination information is provided to the passing mesh calculation device 160. When inputting the destination information, the user searches and sets the destination POI using the destination address, category, telephone number and the like as keys. POI is an abbreviation for Point Of Interest, and is information about points such as store information.

  The route search type information is information indicating the type of route search condition. The types of route search type information include, for example, “minimum required time route” that aims to arrive at the destination in the minimum time, “minimum fuel consumption route” that aims to arrive at the destination with the minimum fuel consumption, There is a “shortest route” that aims to minimize the distance to the destination. The passing mesh calculation device 160 and the route search device 170 are executed so as to minimize an index corresponding to the route search type received by the destination input device 110. This index is a cost. For example, when the route search type information is “minimum required time route”, the travel time to the destination, and when the route search type information is “minimum fuel consumption route”, When the fuel consumption to the destination and the route search type information are “shortest route”, it is the distance to the destination.

  Sensors 120 refer to GPS, vehicle speed pulses, angular velocity sensors, and the like. By using this sensor, the position, vehicle speed, and angular velocity of the vehicle can be measured. These pieces of information are provided to the vehicle position calculation device 130.

  The own vehicle position calculation device 130 calculates the position of the own vehicle from the information of the sensors 120. For this calculation, a known technique such as a Kalman filter or dead reckoning is used. Information about the calculated vehicle position is provided to the route search device 170 via the passage mesh calculation device 160. The own vehicle position information is represented by latitude and longitude, for example.

  The map data 140 is stored in a storage device such as a hard disk or a flash memory, and includes road data and POI information. Road information and POI information corresponding to the map areas of the passing mesh calculation device 160 and the route search device 170 are provided.

  A block diagram of the map data 140 is shown in FIG. FIG. 2A shows the configuration of road data stored in the map data 140. Road data is composed of links from node to node. There are two types of nodes: normal nodes that are provided at road intersections and map nodes provided at mesh boundaries. A map node is distinguished from a normal node by a map node flag. For example, when the node is a map node, “1” is set to the map node flag, and when the node is a normal node, “0” is set to the map node flag. Each road data includes a link ID for identifying a road, a mesh ID in which the road link exists, a node ID at the start of the road link and its latitude / longitude / altitude information, a map node flag, a node ID at the end of the road link, It is composed of latitude / longitude / altitude information, map box node flag, road type, regulation information, and cost data. The restriction information includes speed limit information, one-way information, and the like. In addition, when an interpolation point is prescribed | regulated on the link between nodes, you may prescribe | regulate a link between a node and interpolation points, and between interpolation points. Further, the altitude of the road link may be represented by gradient information instead of the altitude information of the start / end nodes.

  Here, the mesh is a unit section obtained by a method of partitioning a map into a mesh pattern based on latitude and longitude. The secondary mesh is a mesh having a side length of about 10 km obtained by dividing with a latitude difference of 5 minutes and a longitude difference of 7 minutes 30 seconds. The tertiary mesh is a mesh obtained by dividing the secondary mesh into 10 equal parts in the latitude and longitude directions, and has a latitude difference of 30 seconds, a longitude difference of 45 seconds, and a side length of about 1 km. A mesh can be specified by the mesh ID.

  Here, the road type is information representing the type of road link. The road type is, for example, “0” if the road link is an intercity highway, “1” if it is an intracity highway, “2” if it is a national road, and “3” if it is any other road. Is set.

  Here, the cost data is a weight related to the road link used in the route search. For example, statistical traffic information is an example of cost data. This statistical traffic information is created by statistically processing the traffic congestion information acquired and accumulated by the real-time information acquisition device 200. This statistical processing is created for every day type such as weekdays and holidays, and every hour such as 0:00 and 23:00. FIG. 2D shows the structure of cost data.

  Here, the map node is a node for dividing the road link at the boundary of the mesh for management in the map data 140 when the road link between the normal nodes straddles the mesh. When one end or both ends are defined by the maple node, the road link does not exist across the mesh. FIG. 3 shows an example of a map box node. When road links between normal nodes straddle adjacent meshes with mesh IDs 001 and 002 (FIG. 3 (a)), the road links are divided at mesh boundary lines, and the divided road links are managed by each mesh. To do. At this time, the division position is stored in the map data 140 as a map node. In addition, a pair of map nodes defined at the same division position on the same road link at the mesh boundary has a common node ID 001 between adjacent meshes. Therefore, the in-vehicle terminal device 100 can know to which mesh the mesh with the mesh ID 001 is connected by the road link (FIG. 3B).

  FIG. 2B shows a mesh management table included in the map data 140 together with the road data shown in FIG. In this mesh management table, the mesh ID and the coordinates (latitude / longitude) of the vertices of the lower left, upper left, lower right, and upper right of the mesh are set (see FIG. 2C).

  The mesh cost data 150 is generated by an external center device or the like as in the second embodiment to be described later, and is then stored in advance in a storage device such as a hard disk or a flash memory of the in-vehicle terminal device 100, Represents the cost of a route that connects Guo nodes.

  The passing mesh calculation device 160 calculates the destination information from the destination input device 110, the own vehicle position information from the own vehicle position calculation device 130, and the cost of the route connecting the map nodes in the mesh from the mesh cost data 150. Acquire and determine the passing mesh. Further, the map data of the passing mesh is acquired from the map data 140 and developed in the memory.

  The route search device 170 acquires the map data developed in the memory by the passage mesh calculation device 160, and calculates the route inside the passage mesh. The calculated route inside the passing mesh is stored in the route search result storage device 180.

  The route search result storage device 180 is a storage device such as a hard disk or a flash memory, and stores the route output by the route search device 170 and the information of the passing mesh calculated by the passing mesh calculation device 160.

  The real-time information acquisition apparatus 190 receives travel time for each road link of major roads nationwide from a traffic information service center such as VICS Center (registered trademark), for example. The information update cycle is a predetermined time interval. For the travel time for each link, for example, a vehicle detection device is provided on the road for each road link, and the time required for traveling for each road link is measured, or the probe car is driven while measuring the time for each road link. Can be obtained.

  The comparison device 200 compares the cost of the road link included in the route search result stored in the route search result storage device 180 with the cost of the road link calculated from the real-time information acquired by the real-time information acquisition device 190. Then, it is determined whether there is a mesh that needs to be searched again. If re-searching is necessary, information on meshes that require re-searching is transmitted to the route searching device 170.

  When the route search device 170 receives information about the mesh that needs to be re-searched from the comparison device 200, the route search device 170 obtains real-time information about the route from the start-side map node to the end-point map node of the re-search target mesh. The search is performed again using the real-time information acquired by the apparatus 190.

  The display device 220 is a liquid crystal display or the like, and displays the route search result from the route search result storage device 180.

  Hereinafter, configurations and processing flows of the mesh cost data 150, the passing mesh calculation device 160, the route search device 170, the route search result storage device 180, and the comparison device 200 will be described.

  A configuration diagram of the mesh cost data 150 is shown in FIG. FIG. 4A shows a configuration example of cost data for each mesh stored in the mesh cost data 150. In the mesh cost data 150, the number n of routes connecting the map nodes of a specific road type in the mesh, the map node ID of the start point and the map node ID of the end point corresponding to each route, and the cost of the route Data is managed in mesh units. Each route is a result of a route search using the map data 140 with a combination of maple nodes as a start point and an end point, and the cost data of this route is stored in the mesh cost data 150. This cost data is composed of the cost data of the route search result for each route search type information that can be input by the destination input device 110 and the number of costs. FIG. 4A shows a route search result of “shortest route” and its cost when the map node ID 101 of the mesh ID “001” shown in FIG. 4B is the start point and the map node ID 102 is the end point. It is managed as cost data. Similarly, the “minimum time path” and the “minimum fuel consumption path” in FIG. 4A are executed by performing a route search with the map node ID 101 of the mesh ID “001” as the start point and the map node ID 102 as the end point. Calculated. Similarly, details are omitted, but the route search result of “shortest route” and its cost are managed when the map node ID 101 in the same mesh is the start point and the map node ID 103 is the end point. ing. In this way, although not shown in the figure, for each combination when any two of the contour node IDs 101 to 103 in the same mesh are set as the start point and the end point, that is, six routes (n = 6) ), The route search result of “shortest route” and its cost are managed. As will be described later, the minimum cost route corresponding to the route search type information input by the destination input device 110 is extracted from the “shortest route”, “minimum time route”, and “minimum fuel consumption route”. The Based on the cost data of the minimum cost route, the minimum cost of the route connecting the contour nodes in the mesh is determined. In the cost data for each mesh shown in FIG. 4A, the details of the cost data of the mesh ID “002” are omitted from the details of the cost data of the mesh ID “001” described above. It is managed. In this way, cost data for each mesh is stored in the mesh cost data 150.

  A processing flow for creating the mesh cost data 150 by the external center device will be described with reference to FIG. This process is a process in the previous stage of the route search, and map data is input.

  First, it is determined whether all the meshes of the map data have been processed (step S101). If processed (Yes in step S101), the process ends. If not processed (No in step S101), a map road node in the target mesh is extracted for a specific road type (step S102). For example, an intercity highway, an intracity highway, and a national road are extracted. This is because the number of nodes increases when handling the map nodes of all road types, so the number of nodes is reduced based on the road type. Next, it is determined whether or not all map nodes extracted in step S102 in the target mesh have been processed (step S103). If processed (Yes in step S103), the process proceeds to step S101. If it has not been processed (No in step S103), the map node being processed is set as the target map node, and the process proceeds to step S104. At this time, the target map node ID is set to “I”. In step S104, it is determined whether all the map node IDs in the target mesh other than the target map node ID “I” have been processed (step S104). If processed (Yes in step S104), the process proceeds to step S103. If it is not processed (No in step S104), a map node ID “J” (different from I and J) in the target mesh other than the target map node ID “I” is extracted and a route search is performed ( Step S105). At this time, a route is calculated with the target map node ID “I” as the starting point and the map node ID “J” as the end point. The route is calculated using a Dijkstra's algorithm, which is a known technique. The cost used for the search uses a route search type that can be set by the destination input device 110, and the route search is also executed for each route search type. Next, the starting point map node ID, end point map node ID, and cost calculated in the route search used in step S105 are stored as mesh costs in the mesh cost data 150 (step S106). However, if the road link connecting the map nodes of the specific road type does not exist in the target mesh, a value capable of determining that no road link exists, for example, “−1” is input in the cost item. The After step S106 ends, the process proceeds to step S104.

  As shown in FIG. 7, the passing mesh calculation device 160 determines which mesh M passes from the map node O on the departure point S side to the map node D on the destination G side during the route search. To do. The plurality of meshes M that pass is defined as a passing mesh M0. The starting point side map node O is located at the boundary between the starting point side mesh MS including the starting point S and the passing mesh M0 adjacent thereto. The destination side map line node D is located at the boundary between the destination side mesh MG including the destination G and the passing mesh M0 adjacent thereto. In FIG. 7, the hatched mesh is a passing mesh M0 that connects the map node O on the departure point S side and the map node D on the destination M side. The passing mesh calculation device 160 uses the mesh cost stored in the mesh cost data 150 to perform a route search from the contour node O to the contour node D for each mesh M included in the passage mesh M0. In FIG. 7, the map nodes in each passing mesh M <b> 0 are connected by line segments, but such notation is provided for convenience to explain that there is a route connecting the map nodes. The line segment itself is not included in the mesh cost data 150 described above. The same applies to the drawings subsequent to FIG.

  The processing flow of the passing mesh calculation device 160 will be described with reference to FIG. First, candidate maple nodes around the departure point and the destination are extracted (step S201). A candidate map node is a map node that exists around the departure point and the destination and can be reached from the departure point and the destination. The candidate map nodes that exist around the departure point and the destination are not only the case where the candidate map node is included in the mesh to which the departure point and the destination belong, It also means a case where it is included in an adjacent mesh of the mesh to which it belongs. FIG. 8 shows an example of candidate maple nodes O1 to O4 on the departure point S side. Because the road link L12 with the departure place S is connected, the map-line nodes O1 and O2 are candidate map-line nodes. However, since the map outline nodes O3 and O4 are located on the road link L34 and are not connected to the departure place S by a road link, they are not candidate map outline nodes.

  A detailed processing flow of step S201 will be described with reference to FIG. First, a map area node around the departure place and around the destination is extracted (step S301). Here, all the map contour nodes to which the departure point and the destination belong are extracted. Next, it is determined whether or not all the extracted map nodes have been processed (step S302). If not all have been processed (No in S302), a route search is performed to the extracted map node, and it is determined whether the extracted map node is a candidate map node (step S303). In the example of FIG. 8, the map data 140 is used from the starting point S to the map nodes O1, O2, O3, O4 located at the boundary between the starting point side mesh MS including the starting point S and its adjacent mesh. Route search. If there is road network data from the departure place S to the map nodes O1, O2, O3, and O4, it is determined as a candidate map node (in the example of FIG. 8, the map nodes O1 and O2 correspond). If there is no road network data from the departure point to the map node, or if the cost is greater than a predetermined value as a result of the route search, the extracted map node is not selected as a candidate map node (Fig. In the example of 8, O3 and O4 are applicable). In the case of the maple node on the destination side, a route search from the destination to the maple node is performed. When all the processes are performed (Yes in S302), it is determined whether or not there are one or more candidate maple nodes on the destination side and the departure side (step S304). If there is a candidate maple node (Yes in S304), the process ends. If there is no candidate map node (No in S304), the range for searching the map node is expanded, and the process proceeds to step S302 (step S305). Extending the search range means that adjacent meshes are also targeted for search. Within the expanded search range, mesh contour nodes around the starting point and the destination are newly extracted.

  Returning to the processing flow of FIG. After deciding candidate maple nodes in step S201, it is determined whether all combinations of candidate maple nodes on the departure side and destination side have been processed (step S202). If all combinations of map nodes have been processed (Yes in step S202), the process ends.

  If all combinations of map nodes have not been processed (No in step S202), the “shortest path”, “minimum time path”, and “minimum fuel consumption path” included in the mesh cost data 150 are The cost data of the minimum cost route corresponding to the route search type information input by the ground input device 110 is extracted as the minimum cost from the mesh cost data 150, and the route search is performed (step S203). FIG. 10 shows an example of step S203. There are four combinations of the candidate map nodes O1 and O2 on the departure side and the candidate map nodes D1 and D2 on the destination side: O1 to D1, O1 to D2, O2 to D1, and O2 to D2. Here, using the mesh cost stored in the mesh cost data 150, the route search is performed using the candidate map node O1 or O2 as the departure point and the candidate map node D1 or D2 as the destination. FIG. 10 shows an example in which the combination of candidate map contour nodes O1 and D2 is a combination of the departure point and the destination, and an example in which the combination of candidate map contour nodes O2 and D1 is a combination of the departure point and the destination. Yes. Another route search is possible when the candidate map-line node O1 is the departure point and the candidate map-line node D2 is the destination. On the other hand, in the route search when the candidate map node O2 is the departure point and the candidate map node D1 is the destination, the route connecting the map node N1 to the map node N2 in the middle mesh is in the mesh. Because there is no, it is not established. Therefore, in this example, a plurality of meshes including paths connecting the map nodes between the candidate map nodes O1 to D2 are passing meshes.

  When the passing mesh is determined, information about the passing mesh including information on the starting point side map node and the destination side map node is stored in the route search result storage device 180 (step S204). FIG. 11A shows a configuration diagram of the information on the passing mesh stored in the route search result storage device 180 in step S204. When there are a plurality of sets of passing meshes, the route search result storage device 180 stores information on the plurality of sets of passing meshes. The information on the passing mesh includes the map node ID on the departure side, the map node ID on the destination side, the number of passing meshes, the sum of mesh costs calculated in the route search in step S203, and detailed passing mesh information DMM. . Information included in the detailed passing mesh DMM will be described with reference to the example of FIG. Detailed passing mesh information DMM is stored for the number of passing meshes, and is stored in ID (001), starting point map node ID (101), end point map node ID (102), and cost data 150 of the passing mesh. The cost data includes a mesh cost (200 m) between the start point map node ID (101) and the end point map node ID (102). There are two map nodes in the passing mesh. These map nodes are located at both ends of the route obtained in step S203. The starting map node (101) closest to the starting point is the starting map node and the end map node closest to the destination. (102) is defined as the destination side map node. The detailed passing mesh DMM in FIG. 11A also includes data on the passing mesh ID002. However, in the example of FIG. 11B, since there is only one passing mesh, only the data of ID001 of the passing mesh is stored in the detailed passing mesh DMM in FIG. 11A corresponding to this. It will be.

  Next, the route search device 170 will be described according to the processing flow of FIG. FIG. 13 shows an example of a conceptual diagram of route search processing executed in accordance with the processing flow of FIG. First, passing mesh information with the minimum cost is acquired (step S401). In this process, among the passing mesh information stored in the route search result storage device 180 by the processing of the passing mesh calculation device 160, the one having the minimum cost sum is acquired. At this time, as shown in FIG. 13 (a), a passing mesh including the contour node N between the departure point and the destination is selected. Next, for each mesh included in the acquired passing mesh, a route search is performed using the departure side map node O as the departure point and the destination side map node D as the destination (step S402). This route search processing is performed by developing the mesh data to be processed among the road network data stored in the map data 140 on the memory and searching for the route using the cost data for each road link. The result of the route search is expressed as shown in FIG. After the route search is completed for all meshes, the route search result is stored as route data in the route search result storage device 180 (step S403). FIG. 14 shows an example of the configuration of route data stored in the route search result storage device 180. The route data configuration shown in FIG. 14A will be described using the example of FIG. The route data includes, for each passing mesh, the start point map node ID (101), the end point map node ID (102), the number of road links constituting the route (3), and the road link IDs (1001, 1002, constituting the route). 1003) and its cost (30 m, 50 m, 20 m).

  Next, the processing flow of the comparison apparatus 200 will be described with reference to FIG. The processing flow of the comparison device 200 is executed at the timing when the real-time information is acquired or at a predetermined time interval. First, a route search result is acquired from the route search result storage device 180 (step S501). Next, the information acquired by the real-time information acquisition device 190 is compared with the route search result to determine whether or not a re-search is necessary (step S502). When the route search device 180 searches for a route using the minimum time of the mesh cost data, the cost is the travel time passing through the road link. The travel time taken into consideration when creating the mesh cost data is obtained by statistically processing the past travel time. However, when a situation occurs that cannot be covered by past traffic information, re-searching is necessary. For example, when information that a traffic accident has occurred and traffic congestion has occurred on the route is acquired by the real-time information acquisition device 190, it is necessary to search again to avoid this traffic congestion. Whether or not to search again is determined in step S502. In step S502, for example, when it is detected that the difference between the travel time of the acquired real-time traffic information and the travel time of statistical traffic information obtained by statistically processing past traffic information is greater than or equal to a threshold value, or accident occurrence information Affirmative determination is made when. If it is determined to search again (Yes in step S502), the route search device 170 is requested to perform a search again, and the process ends (step S503). When requesting a re-search, the ID of the passing mesh that needs to be re-searched is transmitted to the route search device 170. As will be described later, the route search device 170 performs a re-search on the passing mesh that needs to be re-searched. On the other hand, when it is determined in the determination as to whether or not to search again that it is not necessary to search again (No in step S502), the process is terminated.

  FIG. 16 is a diagram illustrating details of the processing in step S502 as steps S5021 to S5024. Hereinafter, the processing flow of FIG. 16 will be described. However, steps S501 and S503 are the same as those in FIG. After obtaining the route search result in step S501, in step S5021, it is determined whether or not the processing in steps S5022 and S5023 described later has been performed for all meshes including the route obtained in step S501. If the determination is affirmative, the process proceeds to step S5024. In the case of negative determination, in step S5022, the difference between the cost of the real-time information acquired by the real-time information acquisition device 190 and the cost of the road link of the route search result stored in the route search result storage device 180 is a threshold value. It is determined whether it is above. In step S5022, the cost (CR) of the real-time information of the link corresponding to the link ID stored in the route search result storage device 180 is acquired in the processing target mesh. Further, the link cost (CM) of the link ID stored in the route search result storage device 180 is acquired. When all the road links on the route are processed and the difference between the cost of the real-time information and the cost of the route search result is equal to or greater than the threshold (Yes in step S5022), the mesh in which the road link exists is set as a re-search request target. (Step S5023). The process returns to step S5021.

  If there is no road link whose cost difference between the real-time information and the route search result is equal to or greater than the threshold in the processing target mesh (No in step S5022), the process returns to step S5021. If the determination in step S5021 is affirmative, it is determined whether there is a mesh that has been a re-search request target in step S5023 (step S5024). If the determination is affirmative, the process ends through step S503 described above. If the determination is negative, the process ends immediately. For example, the cost CR is the link travel time when the vehicle travels on the road link based on the real-time traffic information, and the cost CM is the link travel when the vehicle travels on the road link based on the statistical traffic information or the regulated speed. It will be time. At this time, the cost CR is compared with a threshold value calculated from the cost CM. The predetermined threshold value is a cost k * CM obtained by multiplying the cost CM by a coefficient (k). For example, when the cost is the link travel time and the CM is 60 seconds and the coefficient k is 3, the threshold is 180 seconds. When the cost CR according to the real-time traffic information is 200 seconds, it is larger than the threshold value of 180 seconds, so that the mesh existing in this road link is determined as a re-search target. This threshold value may be a function corresponding to an estimated elapsed time from when the vehicle departs from the departure place S to travel on the road link.

  Next, the re-search process of the route search device 170 will be described. A conceptual diagram of the re-search process is shown in FIG. As shown in FIG. 17, when the re-search by the route search processing 170 is executed, the map node N from the candidate map node O1 closest to the departure point S to the candidate map node D2 closest to the destination G is displayed. The passing mesh MO passing through is already determined. The route search device 170 searches for the minimum cost route in the re-search target mesh MR among the passing meshes MO. This search uses a real-time information input from the real-time information acquisition device 190 for a route search from the departure side map node OR of the re-search target mesh MR to the destination side map node DR of the re-search target mesh MR. And execute. The cost used for the search uses a route search type that can be set by the destination input device 110. At this time, the map data 140 is used. In this way, the minimum cost route of the re-search target mesh MR determined by the comparison device 200 is updated in the passing mesh MO stored in the route search result storage device 180. The re-searched route RR obtained as the route search result may be different from the route calculated when the mesh cost data 150 is first calculated. Further, the mesh cost data from OR to DR of the re-search target mesh MR is updated with the cost data of the minimum cost path. After updating, the total mesh cost of the passing mesh MO is also updated. After updating the cost data of the minimum cost path between the map nodes through which the passing meshes in all the meshes MR to be re-searched pass as the mesh cost data between the map nodes, the path search device 170 performs step S401. Processing is executed. At this time, a route search is performed using the updated mesh cost.

  In the display device 220, an optimum route display screen showing the route search result of the route search result storage device 180 is displayed on the display and presented to the user. A display example is shown in FIG. FIG. 18A shows a route search result of the route search result storage device 180 superimposed on the map as an optimum route 1810 when a route search from the departure point S to the destination G is performed, and further, using a balloon 1820. The cost “20 minutes required” to the destination is presented.

  Another example of display is shown in FIG. In this example, the passing mesh is calculated from the passing mesh calculation device 160, and information of the passing mesh 1910 is displayed on the display during the processing of the route search device 170 (FIG. 18B) and presented to the user. . Furthermore, a “passing mesh” is presented using a balloon 1920. When the route search result is output from the route search device 170, the displayed information of the passing mesh is replaced with the information of the route search result and displayed on the display (FIG. 18A) and presented to the user. ing. In FIG. 18B, information of the passing mesh 1910 is represented by hatching. On the actual display, for example, the boundary line of the mesh is displayed on the map, and in FIG. 18B, the passing mesh represented by hatching is colored and highlighted.

The in-vehicle terminal device 100 according to the first embodiment described above has the following operational effects.
(1) The in-vehicle terminal device 100 includes a node ID at the start of the road link and its latitude / longitude / altitude information, a map node flag, a node ID at the end of the road link, and its latitude / longitude / altitude information, a map node It has map data 140 in which road data including a flag and cost data is associated with a mesh ID defined on the mesh management table. Moreover, it has the real-time information acquisition apparatus 190 which acquires real-time information. The in-vehicle terminal device 100 has a passing mesh calculation device 160. The passing mesh calculation device 160 determines the departure place S of the vehicle in which the in-vehicle terminal device 100 is mounted based on the map data 140 in steps S201 to S203 in FIG. The destination side mesh MG including the destination G of the vehicle and the destination side mesh from the starting point side map node O positioned at the boundary between the starting point side mesh MS including the passing mesh M0 adjacent to the starting point side mesh MS. A plurality of passing meshes M0 including the minimum cost path to the destination side map node D located at the boundary with the passing mesh M0 adjacent to the MG is acquired. In each passing mesh M0 among the plurality of passing meshes M0, each passing mesh M0 and at least one adjacent passing mesh M0 of each passing mesh M0 are start point map nodes at both ends of the minimum cost path in each passing mesh M0. The mesh cost representing the cost of the minimum cost path when sharing the end point map node is stored in the storage device in advance. The in-vehicle terminal device 100 includes a comparison device 200, and the comparison device 200 includes a road link included in the minimum cost route from the departure side map node O to the destination map node D in the processing step S5022 of FIG. Whether or not to update the mesh cost between the contour nodes of the passing mesh M0 including the road link is determined based on the cost of the current road and the real-time information regarding the road link. When an affirmative decision is made to perform the update, the route search device 170 updates the mesh cost between the contour nodes of the re-search target mesh MR, and in the re-search target mesh MR corresponding to the updated mesh cost. Find the minimum cost path. The route search device 170 updates the plurality of passage meshes M0 based on the updated mesh costs between the contour nodes of the passage meshes, and the updated plurality of passage meshes M0 and the minimum cost route in the re-search target mesh MR. Based on the above, the route from the departure point S to the destination G is searched. That is, the in-vehicle terminal device 100 using the pre-calculated mesh cost determines whether or not to update the mesh cost of the passing mesh from the real-time traffic information, and updates the mesh cost when an affirmative determination is made, thereby searching for a route. The situation that cannot be assumed in the previous cost calculation stage can be considered. Therefore, the user can efficiently execute a route search corresponding to real-time information.

(2) In the in-vehicle terminal device 100, the comparison device 200 determines that the difference between the road link cost CM based on the statistical traffic information or the regulated speed and the road link cost CR based on the real-time information is equal to or greater than a predetermined threshold value of 180 seconds. It was decided to affirmatively update the mesh cost of the passing mesh. Therefore, when the road link cost CM based on the statistical traffic information or the regulated speed and the road link cost CR based on the real-time information are substantially equal, the user can use the mesh of the passing mesh of the re-search target mesh MR by the route search device 170. The route from the departure point S to the destination G searched by the route search device 170 can be obtained without updating the cost.

(3) As the road link farther from the departure place S, the real-time information acquired at the time of departure for the road link may be less effective when the vehicle travels on the road link. In the in-vehicle terminal device 100, the predetermined threshold value may be a function corresponding to an estimated elapsed time from when the vehicle departs from the departure place S to travel on the road link. Therefore, by increasing the predetermined threshold as the road link is farther from the departure place S, it is possible to make it difficult to update the mesh cost of the passing mesh based on the real-time information.

(4) The in-vehicle terminal device 100 further includes mesh cost data 150 in which the mesh cost calculated by the passing mesh calculation device 160 is associated with the start point map node and the end point map node. The route search device 170 refers to the mesh cost included in the mesh cost data 150 and acquires a plurality of passing meshes M0. Therefore, a plurality of passing meshes M0 can be quickly acquired simply by referring to the mesh cost data 150 generated in advance when searching for a route.

-Second embodiment-
FIG. 19 is a diagram showing an overall configuration of a route calculation system according to the second embodiment of the present invention. The route calculation system includes an in-vehicle terminal device 1000 shown in FIG. 19 (a) and a center shown in FIG. 19 (b). Device 5000. The in-vehicle terminal device 1000 includes a host vehicle position calculation device 130 that calculates the position of the host vehicle from information of the destination input device 110 and sensors 120, a display device 220, and a communication device 310.

  The center device 5000 includes map data 140, mesh cost data 150, passing mesh calculation device 160, route search device 170, route search result storage device 180, real-time information acquisition device 190, comparison device 200, mesh cost data creation device 210, communication. It has a device 320. The mesh cost data creation device 210 creates the mesh cost data 150 according to the processing flow shown in FIG.

  The in-vehicle terminal device 1000 and the center device 5000 are connected by communication devices 310 and 320. The communication devices 310 and 320 may be a cellular phone, a wireless LAN module, a PDA (Personal Digital Assistance), a modem integrated with the in-vehicle terminal device 1000 or the center device 5000. When the center device 5000 executes the route search device 180, the processing load on the in-vehicle terminal 1000 during the route search can be reduced. The route calculated by the center device 5000 is sent to the in-vehicle terminal device 1000 via the communication device 320.

  The in-vehicle terminal device 1000 receives the destination information from the destination input device 110, the route search type information, and the own vehicle position information from the own vehicle position calculation device 130 via the communication device 310, and transmits them to the center device 5000. To do.

  The center device 5000 receives these pieces of information via the communication device 320 and inputs them to the route search device 170.

  The route search result stored in the route search result storage device 180 of the center device 5000 is transmitted to the in-vehicle terminal device 1000 via the communication device 320. The in-vehicle terminal device 1000 receives the route search result information via the communication device 310. Further, an optimum route display screen showing the route search result is displayed on the display of the display device 220 and presented to the user.

  In the route calculation system of the second embodiment described above, the in-vehicle terminal device 1000 is replaced with the in-vehicle terminal device 100 of the first embodiment in addition to the operational effects exhibited by the in-vehicle terminal device 100 of the first embodiment. There is an effect that it can be realized as a smaller apparatus.

-Modification-
(1) In the first and second embodiments described above, the mesh cost data 150 is the cost data relating to the mesh cost obtained as a result of the route search in the mesh for each route search type and all the road links constituting the route in the mesh. It is good also as including ID. Since the in-mesh route search is performed based on the route search type, the configuration of the road links constituting the in-mesh route may differ depending on the route search type. A configuration diagram of the mesh cost data 150 is shown in FIG. The mesh cost data 150 includes the number of road links and road link IDs constituting the in-mesh route obtained as a route search result for each route search type, in addition to the cost data regarding the mesh cost for each route search type. At this time, the road link ID is stored in order from the starting point side map node. Since the mesh cost data 150 stores cost data related to two types of mesh costs such as “shortest path” and “minimum time path”, 2 is set as the number of mesh cost types. FIG. 20B shows a route corresponding to the route search type “shortest route” and a route corresponding to “minimum time route”. The number of road links constituting the shortest route is “3”, and the road link IDs constituting the shortest route are “1001”, “1002”, and “1003” in order from the map node on the starting point side. The number of road links constituting the minimum time path is “2”, and the road link IDs constituting the minimum time path are “1004” and “1005” in order from the map node on the starting point side. When this mesh cost data 150 is used, in step S402 (FIG. 12) executed by the route search device 170, road links that constitute the route are referred to according to the route search type of the mesh cost data 150.

(2) In the description of the above embodiment, the threshold value used in the determination process in step S5022 has been described for the case where the link cost is the link travel time. When the link cost is the link length, that is, the distance, and when the link cost is the fuel consumption per link, since both are functions of time, the determination process in step S5022 is executed by converting to the time. can do. For example, the link length is converted into time by dividing the link length by the average moving speed of the corresponding road link. For example, the fuel consumption per link is converted into time by multiplying the fuel consumption per link by a predetermined coefficient.

(3) In the above description of the embodiment, the embodiment in which the present invention is applied to the in-vehicle terminal device 100 or 1000 has been described. However, the in-vehicle terminal device 100 or 1000 is, for example, a PND (Personal Navigation Device). Such a detachable device may be used.

100, 1000 In-vehicle terminal device 110 Destination input device 120 Sensors 130 Vehicle position calculation device 140 Map data 150 Mesh cost data 160 Passing mesh calculation device 170 Route search device 180 Route search result storage device 190 Real-time information acquisition device 200 Comparison device 210 Mesh cost data creation device 220 Display device 310, 320 Communication device 1810 Optimal route 1820 Balloon 1910 Passing mesh 1920 Balloon 5000 Center device

Claims (6)

Map data in which road links and meshes that divide a map are associated with each other, and the mesh and at least one adjacent mesh of the mesh share the respective minimum nodes in the mesh with the respective minimum nodes in the mesh. And an end point mesh including an end point of the moving object from a first boundary node located at a boundary between the starting point mesh including the starting point of the moving object and a starting point adjacent mesh adjacent to the starting point mesh, based on the mesh cost representing the cost of the route; Relay mesh acquisition means for acquiring a plurality of relay meshes included in the inter-boundary node connection minimum cost path to the second boundary node located at the boundary with the end point adjacent mesh adjacent to the end point mesh;
Traffic information acquisition means for acquiring current traffic information;
In the mesh including the section road link included in the boundary node connection minimum cost route, a difference between the link cost of the section road link and the current cost of the section road link based on the current traffic information is greater than or equal to a predetermined threshold When updating the mesh cost to represent the cost of a new in-mesh minimum cost path based on the update of the link cost, updating the plurality of relay meshes based on the updated mesh cost, and updating the updated Based on a plurality of relay meshes and the new in-mesh minimum cost route, the route search means for searching for a movement route from the start point to the end point ,
The route calculation device according to claim 1, wherein the predetermined threshold value is a function corresponding to an estimated elapsed time from when the moving body departs from the starting point to when the moving body moves on the section road link . The route calculation device according to claim 1,
The mesh cost calculated by the relay mesh acquisition means further comprises mesh cost data associated with the both end nodes,
The route calculation device according to claim 1, wherein the first route search means acquires the plurality of relay meshes with reference to the mesh cost included in the mesh cost data. The route calculation device according to claim 1,
The mesh cost calculated by the relay mesh acquisition means further comprises mesh cost data associated with the both end nodes,
The route calculation apparatus according to claim 1, wherein the mesh cost data includes data related to the road link constituting the minimum cost route in the mesh. In the route calculation apparatus according to claim 2 or 3 ,
The mesh cost data includes data relating to a plurality of types of costs corresponding to a plurality of types of route search conditions. The route calculation device according to claim 1,
The traffic information acquisition means further acquires accident occurrence information,
The route search device, wherein the route search unit updates the link cost when the traffic information acquisition unit acquires the accident occurrence information when updating the mesh cost. The route calculation device according to claim 1,
A route computation device further comprising a display device that highlights and displays the plurality of relay meshes on the map.

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