JP2010073078A - Apparatus, method, program for managing traffic data - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To appropriately calculate link traffic data of a road link having no statistical traffic data in accordance with distribution density of other road links around the above road link. <P>SOLUTION: A processor 11 compares map data with statistical traffic data for each area of a predetermined size. When a road link having no statistical traffic data is detected, the number of road links included in the area is calculated. When the number of road links is larger than a predetermine value, the area is divided into sub-areas of a size corresponding to the density of the road links around the above road link having no statistical traffic data. The processor 11 calculates link traffic data of the road link having no statistical traffic data on the basis of the statistical traffic data of the other road links included in the sub-areas including the above road link, and distributes the link traffic data along with the statistical traffic data stored in a storage apparatus 12 to a car navigation apparatus 6. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a traffic data management device, a traffic data management method, and a traffic data management program suitable for use in a vehicle navigation system.

  A navigation device mounted on a vehicle (hereinafter referred to as a “car navigation device”) displays a map including a current position of the vehicle and a recommended route to the destination on a display device to a driver driving the vehicle. provide. At this time, the car navigation device has map data represented by a network of roads divided by intersections or highway entrances / exits, etc., and travel time required for each road section of the road network (also called travel time), A recommended route such as a minimum time route to the destination is searched using the traffic data including the average travel speed and the degree of traffic congestion.

  Hereinafter, in this specification, a road portion divided by an intersection or an entrance / exit of an expressway is referred to as “road link” or “link”, and an intersection or expressway that is a connection point of a plurality of road links. The entrance / exit of is called a “node”.

  Usually, traffic data related to road links (hereinafter referred to as “link traffic data”) is acquired by a probe car for measuring traffic data, various vehicle sensors provided on the road side or on the road, and the like. However, since the newly opened road link has no track record of traveling by a probe car or a general vehicle before the opening, the link traffic data is not acquired. Therefore, there is usually no link traffic data for newly opened road links. Therefore, even if a new road link is opened, the car navigation device cannot immediately use the road link for searching for a recommended route.

In order to solve this problem, for example, in the car navigation device disclosed in Patent Document 1, when there is a road link for which no link traffic data is set, the other is included in the area including the road link. The average value of the link traffic data of the road link is set as the link traffic data of the road link, and the recommended route is searched.
JP 2004-347448 A (see paragraphs 0023 to 0024)

  However, in the method for setting link traffic data for road links for which there is no link traffic data disclosed in Patent Document 1, the size of the area including the road links for which the average value of the link traffic data is to be calculated, A mesh having the same size is used regardless of whether the road links are densely present or the road links are sparsely present. Therefore, depending on the size of the mesh, a mesh with dense road links may find the average value of link traffic data for more road links than necessary, and there are sparse road links. In such a mesh, there may be a case where there is not a sufficient number of appropriate roads for which an average value of link traffic data is obtained. Therefore, the average value may not necessarily be an appropriate average value.

  Further, in the invention disclosed in Patent Document 1, calculation of link traffic data for road links for which no link traffic data exists is performed by the car navigation device itself prior to searching for a recommended route, for example, when the power is turned on. It has been broken. For this reason, the processing burden on the car navigation device is increasing.

  In view of the problems of the prior art as described above, an object of the present invention is to appropriately calculate the link traffic data of a road link for which no link traffic data exists according to the distribution density of the road links around the road link. An object of the present invention is to provide a traffic data management device, a traffic data management method, and a traffic data management program that are possible and do not increase the processing load of the car navigation device.

  In order to achieve the object, in the traffic data management device of the present invention, the processing device compares the map data stored in the storage device with the link traffic data for each area of a predetermined size, and the link traffic. If there is a road link for which no data exists, the number of road links included in the area is calculated. If the number of road links is greater than a predetermined value, the road link for which the link traffic data does not exist is calculated. Is divided into sub-areas of a size corresponding to the density of road links around the road, and link traffic data of road links for which no link traffic data exists is included in the sub-area including the road link and link traffic data. It is calculated based on the link traffic data of the road link where there is. In addition, when the number of road links is equal to or less than a predetermined value, the link traffic data of the road link for which no link traffic data exists is included in the area including the road link and the road link for which the link traffic data exists. Calculate based on link traffic data. Thereafter, the processing device delivers the link traffic data stored in the storage device and the calculated link traffic data together to the car navigation device.

  According to the traffic data management apparatus of the present invention, a road link for which no link traffic data exists is calculated based on the link traffic data of another road link in the area or sub-area including the road link. Or because the size of the sub-area is sized according to the density of the road links around the road link for which no link traffic data exists, the number of road links in that area or sub-area is almost the same, More appropriate link traffic data is calculated.

  According to the present invention, link traffic data of a road link for which no link traffic data exists can be appropriately calculated according to the distribution density of the road links around the road link, and the processing load of the car navigation device It is possible to provide a traffic data management device, a traffic data management method, and a traffic data management program that do not increase traffic.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<First Embodiment>
FIG. 1 is a diagram showing an example of a block configuration of a traffic data management device according to the first embodiment of the present invention and an overall configuration of a car navigation system to which the traffic data management device is applied.

  As shown in FIG. 1, the car navigation system 100 according to the first embodiment includes a traffic data management device 1, a map data management device 2, and a traffic data acquisition device 3 connected to each other via a communication network 4. Furthermore, a car navigation device 6 is connected to the communication network 4 via a base station 5 such as a mobile phone communication network.

  In FIG. 1, a map data management device 2 performs map data update and version management associated with the establishment and renovation of roads, and manages the updated map data via a communication network 4 as appropriate. Deliver to the device 1. The map data is provided to the car navigation device 6 via the communication network 4 and the base station 5 or via a portable storage medium (not shown) such as a DVD (Digital Versatile Disk).

  The traffic data acquisition device 3 is, for example, a probe car or various vehicle detectors for measuring traffic data, and acquires traffic data such as link travel time, link travel speed, and traffic congestion level, and the acquired traffic data is Real-time traffic data is provided to the traffic data management apparatus 1 via the communication network 4 or the like. Note that the traffic data acquisition device 3 may aggregate the acquired traffic data as appropriate and provide the traffic data management device 1 as offline traffic data.

  Hereinafter, the configuration and function of the traffic data management device 1 according to the embodiment of the present invention will be described in detail with reference to FIGS. 1 to 6. As shown in FIG. 1, the traffic data management device 1 includes a processing device 11, a storage device 12, a communication device 13 that connects the processing device 11 to an external communication network 4, and the like.

  The processing device 11 includes a CPU (Central Processing Unit) that performs data arithmetic processing, a main storage memory that stores data and programs to be subjected to the arithmetic processing, and the CPU is stored in the main memory. By executing a predetermined program, functional blocks such as a traffic data collection unit 111, a traffic data statistical processing unit 112, a route search traffic data generation unit 113, a route search traffic data distribution unit 114, and a map data acquisition unit 115 are provided. Realized.

  The storage device 12 includes a hard disk device and the like, and stores various data such as current traffic data, statistical traffic data, route search traffic data, map data, and the like, a current traffic data storage unit 121, a statistical traffic data storage unit. 122, a route search traffic data storage unit 123, a map data storage unit 124, and the like.

  FIG. 2 is a diagram showing an example of the configuration of link data and node data as map data. As shown in FIG. 2A, the link data is composed of a link ID, area ID, link type, point sequence data, attribute data, start point node ID, end point node ID, and the like. As shown, the node data includes a node ID, an area ID, a node position, a connection link ID, and the like.

  2A, the link ID is identification information for individually identifying road links included in the map data, the area ID is information for identifying the area to which the road link belongs, and the link type is the type of the road link ( Expressways, national roads, prefectural roads, municipal roads, etc.). Further, the point sequence data is composed of, for example, a plurality of position data represented by longitude and latitude, and is data representing the location and shape of the road link. The attribute data includes data such as the width of the road link, the number of lanes, and the speed limit. The start point node ID and end point node ID are identification information of the start point and end point node of the road link.

  In FIG. 2B, the node ID is identification information for individually identifying a node that is a connection point of road links included in the map data, the area ID is information for identifying the area to which the node belongs, and the connection link ID is , The link ID of the road link having the node as a start point or an end point.

  FIG. 3 is a diagram showing an example of the configuration of link traffic data and statistical traffic data. The link traffic data is a general term for traffic data defined for each road link. As shown in FIG. 3A, the link ID, area ID, link length (d), link travel time ( T), link travel speed (v), congestion degree (c), and other data.

Here, the link length (d) is the distance from the start point to the end point of the road link, the link travel time (T) is the travel time of the road link by the vehicle, and the link travel speed (v) is the vehicle Is the average traveling speed of the road link. Therefore, these data include
Link length (d) = link travel speed (v) × link travel time (T)
A relationship exists. The degree of traffic congestion (c) is data determined by the value of the link travel speed (v) or the length of the vehicle train measured on the road link.

  The processing device 11 (refer to FIG. 1), as the processing of the traffic data collection unit 111, from the traffic data acquisition device 3, traffic data depending on the traffic data acquisition device (for example, vehicle travel speed from a Doppler radar or the like). 3, and based on the acquired traffic data, link traffic data having the configuration of FIG. 3A is generated, and the generated traffic data is associated with the acquisition date and time as current traffic data storage unit 121.

  Subsequently, as the processing of the traffic data statistical processing unit 112, the processing device 11 sorts the current traffic data stored in the current traffic data storage unit 121 for each predetermined time zone, and each road link for each sorted time zone. For the current traffic data, average values of link travel time (T), link travel speed (v), traffic jam (c), etc. are obtained and stored in the statistical traffic data storage unit 122 as statistical traffic data.

  Here, the time zone is a day divided into predetermined time intervals (for example, every hour, every 10 minutes, etc.), but each time zone does not have to be equal time. For example, one day at midnight (0-4am), early morning (4-7am), morning commuting (7 am-9am), daytime (9 am-16:00), evening commuting (16:00) -20 o'clock), nighttime (20 o'clock-24 o'clock), etc.

  As described above, the statistical traffic data is data obtained by totaling the current traffic data obtained by actual measurement for each predetermined time zone and taking the average. Therefore, the configuration of the statistical traffic data is the same as the configuration of the link traffic data in FIG. 3A except that the time zone data is added as shown in FIG.

  The statistical traffic data may be data obtained by sorting the current traffic data according to the day type (weekdays, weekends, etc.) in addition to the time zone, and taking the average. In this case, the structure of the statistical traffic data is obtained by adding the time zone and day type data to the link traffic data in FIG.

  Subsequently, the processing device 11 performs processing of the route search traffic data generation unit 113 as statistical traffic data stored in the statistical traffic data storage unit 122 and map data (link data) stored in the map data storage unit 124. , Node data) is generated, and the generated route search traffic data is stored in the route search traffic data storage unit 123.

  Here, if there is no newly opened road link and statistical traffic data exists for all road links that exist as link data in the map data, the statistical traffic data should be used as traffic data for route search as it is. Can do. On the other hand, when there is a newly opened road link, there is no statistical traffic data on the newly opened road link. Therefore, the processing device 11 generates link traffic data corresponding to the statistical traffic data for the road link for which the statistical traffic data does not exist as the processing of the route search traffic data generation unit 113.

  That is, when there is a road link without link traffic data in the statistical traffic data, the processing device 11 generates link traffic data for the road link, and adds the generated link traffic data to the statistical traffic data to generate a route. It is set as search traffic data (process of the route search traffic data generation unit 113), and the route search traffic data is distributed to the car navigation device 6 via the communication device 13, the communication network 4, the base station 5, and the like (route). Processing of search traffic data distribution unit 114).

  Next, the details of the processing of the route search traffic data generation unit 113 will be described, but before that, areas referred to as map data will be described. FIG. 4 is a diagram illustrating an example of a form of an area and a form of a road link in the mesh.

  The map data stored in the map data storage unit 124 is divided into areas of a predetermined size and stored, but the area is most simply divided into, for example, a 10 km square. is there. The 10 km square area is often called a mesh. In this specification, a 10 km square mesh frequently used in a general car navigation system is called a basic mesh or simply a mesh, and a sub-mesh of the basic mesh is called a sub-mesh. A sub-mesh further subdivided is also called a sub-mesh.

  In general, the distribution density of road links is high in areas with a large population or areas where human activities are active, and the distribution density of road links is low in areas where the population is small or areas where human activities are not active. In other words, roads are densely provided in the city center of large cities, but roads are provided only sparsely in mountainous areas in rural areas. Incidentally, in the example shown in FIG. 4, the distribution density of road links is low in the upper right basic mesh, and the distribution density of road links is high in the sub-mesh portion at the center of the lower left basic mesh.

  In the processing device 11 (see FIG. 1), as a process of the route search traffic data generation unit 113, a newly opened road (indicated by a broken line in FIG. 4) exists in a certain mesh, and link traffic data (statistical traffic data) is present. When there is a road link that does not exist, the link traffic data of the road link is calculated based on the link traffic data of another road link included in the mesh or sub-mesh including the road link. In that case, the processing device 11 subdivides the size of the mesh or sub-mesh as described below with reference to FIG. Road link) Determine the size according to the density of surrounding road links.

  FIG. 5 is a diagram illustrating an example of a procedure of link traffic data generation processing for a road link for which no link traffic data exists. The processing device 11 executes this link traffic data generation processing as processing of the route search traffic data generation unit 113. Note that the processing procedure shown in FIG. 5 is for processing one area (one basic mesh) of the divided map. When the whole country is targeted, It is necessary to execute the link traffic data generation process shown in FIG.

  The processing device 11 first selects 1-mesh map data from the map data storage unit 124 (step S11). Next, the processing device 11 compares the map data of the selected mesh with the statistical traffic data obtained from the statistical traffic data storage unit 122, and the road link in which no link traffic data exists in the selected mesh. It is determined whether or not there is a road link in FIG. 5 (abbreviated as a link, hereinafter the same in FIG. 5) (step S12). As a result of the determination, if there is no road link for which no link traffic data exists (No in step S12), the processing device 11 ends the link traffic data generation process for the selected mesh.

  On the other hand, when there is a road link for which no link traffic data exists (Yes in step S12), the processing device 11 refers to the map data storage unit 124 and determines the number of road links included in the selected mesh. Calculate (step S13). If the calculated number of road links is less than or equal to the predetermined number of links (No in step S14), it means that there are no road links densely in the mesh, so the processing device 11 The link traffic data of the road link for which no link traffic data exists is generated based on the other link traffic data included in the selected mesh (step S20), and the link traffic data generation process for the selected mesh is terminated. To do.

  On the other hand, if the calculated number of road links is larger than the predetermined number of links (Yes in step S14), it means that the road links are densely present in the mesh. The mesh is subdivided into sub-mesh (step S15). The mesh subdivision may be divided into four equal parts as shown in FIG. 4, or may be divided into nine equal parts or 16 equal parts.

  Subsequently, the processing device 11 selects one of the road links that do not have link traffic data included in the mesh (step S16), selects a sub-mesh that includes the selected road link (step S17), Further, the number of road links included in the sub-mesh is calculated (step S18). If the calculated number of road links is larger than the predetermined number of links (Yes in step S19), it means that road links exist more densely in the submesh. Subdivides the submesh into lower submesh (step S21), returns to step S17, and executes the subsequent processing again.

  On the other hand, when the number of road links calculated in step S18 is equal to or less than the predetermined number of links (No in step S19), the processing device 11 uses the link traffic data of the road link selected in step S16 as step S17. It generates based on the other link traffic data included in the submesh selected in (Step S22).

  Then, the processing device 11 determines whether or not all road links that do not have link traffic data have been selected in step S16 (step S23). If all the road links have not been selected (No in step S23), step 11 is performed. Returning to S16, the subsequent processing is executed again. If all of them have been selected (Yes in step S23), the link traffic data generation process for the mesh selected in step S11 is terminated.

In step S20 and step S22 of the above processing procedure, when generating link traffic data of a road link for which no link traffic data exists, the processing device 11 refers to the statistical traffic data storage unit 122 and refers to the mesh or submesh. The link travel speed (v) of the road link included in is taken out, the average value is calculated, and it is set as the link travel speed (v _x ) of the road link for which no link traffic data exists. Then, based on the link travel speed (v _x ), the degree of congestion (c _x ) is obtained, and further, the link travel time (T _x = d _x / v _x ) in consideration of the link length (d _x ) of the road link. ) Is calculated.

  When calculating the average value of the link travel speed (v), the weight determined in advance according to the link type of each road link (express road, general road, prefectural road, municipal road, etc.) You may make it take a weighted average suitably based on a value. For example, when the newly opened road is a national road, the weight value of the national road is increased, and the weight value of the prefectural road and the municipal road is decreased. In that case, the link travel speed (v) of the prefectural road and the municipal road is higher than the link travel speed (v) of the national road included in the mesh as the average value of the link travel speed (v) of the newly opened road. It is reflected more than the influence of. Thus, by taking a weighted average according to the link type, it is possible to obtain the link traffic data of the road link for which no link traffic data exists in a form that more closely matches the reality.

  Further, according to the link traffic data generation process described above, the maximum value of the number of links in the basic mesh or the submesh can be suppressed to be equal to or less than the predetermined number of links in step S14 and step S19. That is, in the area where the road link density is low, the size of the area is the size of the basic mesh, and in the area where the road link density is high, the area size is subdivided into sub-mesh one after another. . In other words, when generating link traffic data for road links for which no link traffic data exists, the size of the area (basic mesh or submesh) depends on the link density around the road links for which no link traffic data exists. Determined in size.

  Therefore, in this embodiment, link traffic data of road links for which no link traffic data exists is generated without using road traffic of a wider range than necessary or link traffic data of more road links than necessary. can do. In other words, by making the area size according to the link density of road links for which no link traffic data exists, more appropriate link traffic data is generated using the link traffic data of the number of links without excess or deficiency. be able to.

  That is, according to the present embodiment, in a large urban area where roads are densely distributed, the link traffic data of road links for which no link traffic data exists is, for example, the link traffic of road links in the vicinity of 1 km square or 500 m square. It will be generated based on the data. This means that link traffic data for road links for which no link traffic data exists is generated based on link traffic data for neighboring road links that are easily affected. I can say that.

  On the other hand, when the size of the basic mesh is limited to 10 km square, for example, the entrance / exit of the expressway does not exist in the basic mesh, or there are very few such as one or two. There is a case. In such a case, the link traffic data of the expressway road link (link type is expressway) is linked to the other road links of the expressway included only in the basic mesh that includes the expressway road link. Generating based on traffic data is not always appropriate.

  Therefore, when generating link traffic data for road links of expressways that do not have link traffic data, such as newly opened expressways, the basic mesh that includes the newly opened expressway and the basic mesh adjacent to it are used. Merge (the reason for merging will be described later). In the present specification, the merged mesh is hereinafter referred to as an enlarged mesh.

  FIG. 6 is a diagram showing an example of an enlarged mesh at the time of generating highway link traffic data. In FIG. 6, the white squares or shaded squares represent the basic mesh, the small squares represent highway interchanges (entrances and exits) or nodes, and the solid lines connecting the nodes represent existing highway A road link is represented, and a broken line represents a road link of a newly opened expressway.

  In addition, as shown in FIG. 6 (a), the nodes (start node and end node) at both ends of the road link of the newly opened expressway that is the target of link traffic data generation shown by the thick broken line are thick solid line frames. If it is included in the displayed center basic mesh, an area obtained by merging the center basic mesh and the surrounding eight basic meshes becomes an enlarged mesh.

  In addition, as shown in FIG. 6 (b), one of the start node and the end node of the road link of the newly opened expressway displayed with a thick broken line that is the target of link traffic data generation is included, and two adjacent nodes are included. An area obtained by merging the basic mesh (mesh displayed with a thick solid line frame) and the 10 basic meshes around it is an enlarged mesh.

  In addition, as shown in FIG. 6C, one of the start point node and the end point node of the road link of the newly opened expressway displayed with a thick broken line, which is the target of link traffic data generation, is included, and the vertexes are in contact with each other. An area obtained by merging two basic meshes (mesh displayed with a thick solid line frame) and the 12 basic meshes around it is an enlarged mesh.

  Note that the expanded mesh is not limited to be determined as described above, and the neighboring mesh including the basic mesh including at least one of the start node and the end node of the road link of the newly opened expressway. What is comprised with the mesh should just be. For example, in the enlarged mesh shown in FIGS. 6A, 6B, and 6C, a basic link with a thick solid line frame (a basic link including at least one of a start node and an end node of a road link of a newly opened expressway) The basic link displayed in a shaded manner in which only the mesh) and the vertex are in contact with each other may not be included in the enlarged mesh.

  As described above, when generating link traffic data of an expressway that does not have link traffic data, it is not included in one basic mesh but included in an enlarged mesh as shown in FIG. 6, that is, a plurality of basic meshes. By generating the link traffic data based on the link traffic data of other highways, the link length of the highway is long, the traveling speed of the vehicle is high, and therefore the range where the traffic situation affects is wide. It will be more suitable for the special circumstances of the expressway.

  In the above description, when the link traffic data of the expressway is obtained, only the link traffic data of the other expressway is considered, and the influence of the link traffic data of the general road is not reflected. As described above, the influence of link traffic data on ordinary roads may be reflected by taking a weighted average according to the link type.

<First Modification of First Embodiment>
In the first embodiment described above, as shown in FIG. 4, the map data is divided by a square mesh. However, the map data is not divided by a square mesh, for example, by an indefinite area based on an administrative division. May be. In that case, the basic mesh described in the first embodiment is associated with, for example, an area of a municipality, and towns, large letters, districts, and the like in the municipality are subareas corresponding to the submesh. Furthermore, chome, small letters, etc. can be used as lower sub-areas. In that case, the process of generating link traffic data without link traffic data described with reference to FIG. 5 can be applied to a modification of this embodiment as it is.

  In the process of generating link traffic data without link traffic data in FIG. 5, the criteria for subdividing the area or sub-area are included in the area or sub-area, as in the first embodiment. The number of links (see step SS14 and step S19). However, in the modification of this embodiment, it may be subdivided based on the population in the area or sub-area. In this case, it is assumed that the map data stored in the map data storage unit 124 includes population data of each municipality and population data in each town, large letter, district, etc. in each municipality.

<Second Modification of First Embodiment>
In the first embodiment, the route search traffic data is generated based on the statistical traffic data, and the generated route search traffic data is distributed to the car navigation device 6. However, based on the current traffic data, the route search traffic data is distributed. Traffic data may be generated. In the description of the route search traffic data generation unit 113 in the modification of this embodiment, the statistical traffic data in the description of the first embodiment need only be replaced with the current traffic data.

  In the first embodiment, the route search traffic data may be distributed to the car navigation device 6 once a year or when a new road or the like is opened. Then, the route search traffic data needs to be delivered to the car navigation device 6 for each predetermined time zone (a time zone similar to the time zone described in FIG. 3). Accordingly, although the burden on the communication network 4 and the like increases, the car navigation device 6 can obtain route search traffic data suitable for the traffic situation at that time.

<Second Embodiment>
FIG. 7 is a diagram illustrating an example of a block configuration of a route search device according to the second embodiment of the present invention and an overall configuration of a car navigation system to which the route search device is applied. Hereinafter, in the description of the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  As shown in FIG. 7, in the car navigation system 100a according to the second embodiment, a route search device 7, a map data management device 2, and a traffic data acquisition device 3 are connected to each other via a communication network 4, and The car navigation device 6 is connected to the communication network 4 via a base station 5 such as a mobile phone communication network. The route search device 7 includes a processing device 71, a storage device 72, a communication device 73 that connects the processing device 71 to the external communication network 4, and the like.

  Here, the processing device 71 is composed of a CPU that performs arithmetic processing of data, a main memory that stores data and programs to be subjected to the arithmetic processing, and the like, and the CPU stores a predetermined memory stored in the main memory. By executing the program, the traffic data collection unit 111, the traffic data statistical processing unit 112, the route search traffic data generation unit 113, the route search condition acquisition unit 711, the route search unit 712, the route data distribution unit 713, and the map data acquisition Functional blocks such as the unit 115 are realized.

  The storage device 72 includes a hard disk device and stores various data such as current traffic data, statistical traffic data, route search traffic data, and map data. The current traffic data storage unit 121 and the statistical traffic data storage unit. 122, a route search traffic data storage unit 123, a map data storage unit 124, and the like.

  The basic functions from collecting traffic data from the traffic data acquisition device 3 in the route search device 7 to generating route search traffic data are the same as the functions of the traffic data management device 1 in the first embodiment. is there.

  On the other hand, the route search device 7 receives the route search condition transmitted from the car navigation device 6 instead of the function of distributing the traffic data for route search in the traffic data management device 1 (route search condition acquisition unit 711), Based on the received route search condition, a route search is performed (route search unit 712), and the searched route data is distributed to the car navigation device 6 (route data distribution unit 713). Here, the route search condition refers to data necessary for route search, such as the position of the vehicle, the destination, the type of the searched route (shortest distance, shortest time, etc.), whether or not highway driving is possible.

  FIG. 8 is a diagram showing an example of the configuration of map data used in the second embodiment. As shown in FIG. 8, the map data includes (c) POI (Point of Interest) data in addition to (a) link data and (b) node data used in the first embodiment.

  Here, the POI data is classified for each type (often referred to as a category) of leisure facilities, public facilities, various stores, and the like, and is configured by information such as a location, a name, an overview of the facilities and stores. In the car navigation apparatus 6, POI data is often used for setting a destination. Therefore, POI data (POI identification information) is often included as destination data for route search conditions transmitted from the car navigation device 6.

  FIG. 9 is a diagram showing an example of the difference in distribution density depending on the POI category. In FIG. 9A, one square area represents a basic mesh, and an asterisk icon represents the location of a leisure facility. In FIG. 9A, one square area represents a sub-mesh obtained by dividing the basic mesh into four, and a cube icon represents the location of the store.

  As shown in FIG. 9A, for example, there are not many leisure facilities such as amusement parks and zoos. For example, if one or two are distributed in a basic mesh of 10 km square, it is more common. . As shown in FIG. 9B, various stores are densely distributed, particularly in urban areas. For example, there may be several tens or 100 or more in a basic mesh of 10 km square.

  Therefore, the processing device 71 of the route search device 7 is based on the POI data category included as the destination in the received route search condition, and the POI belonging to the category is sparsely distributed in the basic mesh (for example, leisure facilities) ), Link traffic data for road links for which no link traffic data exists is generated based on link traffic data for other road links included in a wide mesh, and route search traffic data is generated.

  On the other hand, when the POI belonging to the category is a POI (for example, a convenience store) distributed in the basic mesh, the link traffic data of the road link having no link traffic data is converted into a narrow mesh including the road link. It generates based on the link traffic data of other road links included, and generates route search traffic data.

  Here, a wide mesh means one basic mesh or an area constituted by a plurality of (four, nine, etc.) basic meshes, and a narrow mesh means that one basic mesh is divided into four or A sub-mesh subdivided into 9 divisions.

  Note that the method of generating link traffic data for road links for which no link traffic data exists is substantially the same as in the first embodiment, but in the second embodiment, a basic mesh or submesh is used. The size of the mesh is determined according to the category of the destination, rather than determining the size of the mesh according to the number of links within. Note that “determined” here is not determined each time, but for example, “four basic meshes for leisure facilities, one basic mesh for restaurants, and 1/4 basic mesh for fast food and convenience stores” And selecting from predetermined ones.

  That is, when the processing device 71 receives the route search condition from the car navigation device 6, based on the destination category included therein, the processing device 71 provides link traffic data of road links for which no link traffic data exists, that is, route search traffic data. Is generated, route search is performed based on the route search traffic data, and the searched route is distributed to the car navigation device 6. However, since it is not efficient to generate the route search traffic data every time the route search condition is received from the car navigation device 6, the processing device 71 generates the route search traffic data in advance for each category. When route search conditions are received, route search is performed using route search traffic data for each category generated in advance.

  As described above, according to the second embodiment, the processing device 71 of the route search device 7 is based on the route search traffic data corresponding to the POI distribution density of the destination category set by the car navigation device 6. And the searched route data is provided to the car navigation device 6. That is, when the destination category is sparsely distributed on one basic mesh such as a leisure facility, route search traffic data based on a wide mesh is used for the route search. In addition, when the destination category includes a large number of distributions in a basic mesh such as a convenience store, route search traffic data based on a narrow mesh is used for the route search.

  As a result, the route search device 7 can search for appropriate route data according to the density at which the POIs of the destination category are distributed, and therefore, the route search device 7 can send the appropriate route data according to the destination category to the car navigation device 6. Can be delivered.

<Modification of Second Embodiment>
In the second embodiment, the size of the mesh when generating link traffic data of a road link for which no link traffic data exists is determined according to the destination category, but in this modification, the vehicle is traveling An example in which the size of the mesh is determined according to the type of road link will be shown.

  FIG. 10 is a diagram showing an example of the difference in distribution density depending on the link type (highway, general road, etc.) of the road link. In FIG. 10A, one square area represents a basic mesh, and a thick broken line represents a road link of an expressway. Further, in FIG. 9B, one square area represents a sub-mesh obtained by dividing the basic mesh into four, and a thick broken line represents a general road (a national highway, a prefectural road, a municipal road, etc.). .

  As shown in FIG. 10A, the highway is distributed only about several links at most in a basic mesh of 10 km square, for example. In addition, as shown in FIG. 10B, ordinary roads are densely distributed, particularly in urban areas.

  Therefore, the processing device 71 of the route search device 7 is based on the vehicle position included as the destination in the received route search condition, and when the vehicle position is an expressway, the road where no link traffic data exists. The link traffic data of the link is generated based on the link traffic data of other road links included in the wide mesh, and the route search traffic data is generated. On the other hand, if the vehicle location is a general road, link traffic data for road links that do not have link traffic data is generated based on the link traffic data for other road links included in the narrow mesh, and route search is performed. Traffic data is generated. Here, the sizes of the wide mesh and the narrow mesh are determined in advance as described in the second embodiment.

  Therefore, in this modification, the route search device 7 can search for appropriate route data according to the distribution density of the road links according to the type of road links on which the vehicle is traveling. Appropriate route data corresponding to the type of road link being traveled can be distributed to the car navigation device 6.

The figure which showed the block configuration of the traffic data management apparatus which concerns on the 1st Embodiment of this invention, and the example of the whole structure of the car navigation system to which the traffic data management apparatus was applied. The figure which showed the example of the structure of the link data as map data, and node data. The figure which showed the example of the structure of link traffic data and statistical traffic data. The figure which showed the example of the form of the road link in the mesh which is one form of an area, and a mesh. The figure which showed the example of the procedure of the link traffic data generation process with respect to the road link in which link traffic data does not exist. The figure which showed the example of the expansion mesh at the time of the link traffic data production | generation of an expressway. The figure which showed the example of the block configuration of the route search apparatus which concerns on the 2nd Embodiment of this invention, and the whole structure of the car navigation system to which the route search device was applied. The figure which showed the example of the structure of the map data used by 2nd Embodiment. The figure which showed the example of the difference in the distribution density by the category of POI. The figure which showed the example of the difference in distribution density by the link classification (Expressway, general road, etc.) of a road link.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Traffic data management apparatus 2 Map data management apparatus 3 Traffic data acquisition apparatus 4 Communication network 5 Base station 6 Car navigation apparatus 7 Route search apparatus 11,71 Processing apparatus 12,72 Storage apparatus 13,73 Communication apparatus 100,100a Car navigation system 111 Traffic data collection unit 112 Traffic data statistical processing unit 113 Route search traffic data generation unit 114 Route search traffic data distribution unit 115 Map data acquisition unit 121 Current traffic data storage unit 122 Statistical traffic data storage unit 123 Route search traffic data storage Unit 124 map data storage unit 711 route search condition acquisition unit 712 route search unit 713 route data distribution unit

Claims (9)

For each area divided into a predetermined size, map data including position data, connection data and road type data of a plurality of road links included in the area,
Link traffic data configured to include at least one of a vehicle link travel speed, a link travel time, and a traffic congestion degree for each of the plurality of road links;
A storage device storing at least
A processing device for performing arithmetic processing of data;
A communication device that communicates with a navigation device mounted on a vehicle via a predetermined communication network;
A traffic data management device comprising:
The processor is
For each area, the map data stored in the storage device and the link traffic data are compared to extract a road link where the link traffic data does not exist,
For an area including a road link for which the link traffic data does not exist, the number of road links included in the area is calculated,
When the number of road links is larger than a predetermined value, the area is further divided into sub-areas having a size corresponding to the density of road links around the road links for which no link traffic data exists, and the links Calculate link traffic data for road links that do not have traffic data based on link traffic data for road links that are included in the sub-area that includes the road link and that have link traffic data.
If the number of road links is less than or equal to a predetermined value, the road traffic link data for which the link traffic data does not exist is included in the area including the road link and the link traffic data exists. Calculated based on the link traffic data of the link,
The link traffic data of the road link for which the calculated link traffic data does not exist and the traffic data stored in the storage device are combined and distributed to the navigation device via the communication device. Traffic data management device. The processor is
Other road links included in the area or sub-area using the link traffic data of road links for which there is no link traffic data, using the load value for each link type preset according to the link type of the road link The traffic data management device according to claim 1, wherein the traffic data management device is calculated by a weighted average of the link traffic data. The processor is
In the case where the map data stored in the map data storage unit and the link traffic data stored in the link traffic data storage unit are compared, and road links without the link traffic data are extracted for each area. When the link type of the road link for which the link traffic data does not exist is a highway,
The area including at least one of the start node and the end node of the road link and the area adjacent to the area are merged, and the link traffic data of the road link having no link traffic data is merged into the merged area. The calculation is based on link traffic data of a road link that includes at least one of a node and an end node, the link type of which is a highway, and link traffic data exists. The traffic data management device described. For each area divided into a predetermined size, map data including position data, connection data and road type data of a plurality of road links included in the area,
Link traffic data configured to include at least one of a vehicle link travel speed, a link travel time, and a traffic congestion degree for each of the plurality of road links;
A storage device storing at least
A processing device for performing arithmetic processing of data;
A communication device that communicates with a navigation device mounted on a vehicle via a predetermined communication network;
A traffic data management method in a traffic data management device configured to include:
The processor is
For each area, the map data stored in the storage device and the link traffic data are compared to extract a road link where the link traffic data does not exist,
For an area including a road link for which the link traffic data does not exist, the number of road links included in the area is calculated,
When the number of road links is larger than a predetermined value, the area is further divided into sub-areas having a size corresponding to the density of road links around the road links for which no link traffic data exists, and the links Calculate link traffic data for road links that do not have traffic data based on link traffic data for road links that are included in the sub-area that includes the road link and that have link traffic data.
If the number of road links is less than or equal to a predetermined value, the road traffic link data for which the link traffic data does not exist is included in the area including the road link and the link traffic data exists. Calculated based on the link traffic data of the link,
The link traffic data of the road link for which the calculated link traffic data does not exist and the traffic data stored in the storage device are combined and distributed to the navigation device via the communication device. To manage traffic data. The processor is
Other road links included in the area or sub-area using the link traffic data of road links for which there is no link traffic data, using the load value for each link type preset according to the link type of the road link The traffic data management method according to claim 4, wherein the traffic data is calculated by a weighted average of the link traffic data. The processor is
In the case where the map data stored in the map data storage unit and the link traffic data stored in the link traffic data storage unit are compared, and road links without the link traffic data are extracted for each area. When the link type of the road link for which the link traffic data does not exist is a highway,
The area including at least one of the start node and the end node of the road link and the area adjacent to the area are merged, and the link traffic data of the road link having no link traffic data is merged into the merged area. 5. The calculation according to claim 4, wherein at least one of a node and an end node is included, and the link type is a road link that is an expressway, and is calculated based on link traffic data of a road link for which link traffic data exists. The traffic data management method described. For each area divided into a predetermined size, map data including position data, connection data and road type data of a plurality of road links included in the area,
Link traffic data configured to include at least one of a vehicle link travel speed, a link travel time, and a traffic congestion degree for each of the plurality of road links;
A storage device storing at least
A processing device for performing arithmetic processing of data;
A communication device that communicates with a navigation device mounted on a vehicle via a predetermined communication network;
A traffic data management program in a traffic data management device configured to include:
In the processing device,
For each area, the map data stored in the storage device and the link traffic data are compared, and a road link where the link traffic data does not exist is extracted.
For an area including a road link for which the link traffic data does not exist, the number of road links included in the area is calculated,
When the number of road links is larger than a predetermined value, the area is further divided into sub-areas having a size corresponding to the density of road links around the road links for which no link traffic data exists. Link traffic data for road links that do not have traffic data is calculated based on link traffic data for road links that are included in the sub-area that includes the road link and for which link traffic data exists,
If the number of road links is less than or equal to a predetermined value, the road traffic link data for which the link traffic data does not exist is included in the area including the road link and the link traffic data exists. Calculating based on link traffic data of the link;
The calculated link traffic data of a road link for which the link traffic data does not exist and the traffic data stored in the storage device are delivered to the navigation device via the communication device. Traffic data management program. In the processing device,
Other road links included in the area or sub-area using the link traffic data of the road link for which the link traffic data does not exist, using the load value for each link type set in advance according to the link type of the road link The traffic data management program according to claim 7, wherein the traffic data is calculated by a weighted average of the link traffic data. In the processing device,
In the case where the map data stored in the map data storage unit and the link traffic data stored in the link traffic data storage unit are compared, and road links without the link traffic data are extracted for each area. When the link type of the road link for which the link traffic data does not exist is a highway,
The area including at least one of the start node and the end node of the road link and the area adjacent to the area are merged, and the link traffic data of the road link without the link traffic data is merged into the merged area. The calculation is based on link traffic data of a road link that includes at least one of a start node and an end node, and whose link type is a highway, and for which link traffic data exists. Traffic data management program described in 1.

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