Map delivery device, onboard device, and map delivery system

Abstract

Provided are: a map delivery device with which, when map data is being updated along a path, update-data narrowed down to a necessary range in accordance with a type of road in path information is delivered, thereby enabling a reduction in the delivery data volume, a reduction in communication costs, and the prevention of degradation in performance of map update processing; an onboard device that receives map data from the map delivery device; and a map delivery system configured so that the map delivery device and the onboard device are able to communicate. (A map delivery device 10 of) a map delivery system 1 of the present embodiment manages map data in different segmental schemes depending on the type of road (expressway, general road), and delivers the map data of the different segmental schemes depending on the type of road in path information. When the type of road in the path information is an expressway segment, map data of a route-unit segmental scheme managed along a route is delivered. When the type of road in the path information is a general road segment, map data of a mesh-unit segmental scheme managed by segmenting into predetermined regions is delivered.

Description

Map distribution device, in-vehicle device, and map distribution system

[0001] The present invention relates to a map distribution device, an in-vehicle device that receives map data from the map distribution device, and a map distribution system configured so that the map distribution device and the in-vehicle device can communicate with each other.

[0002] One known method for updating map data for an in-vehicle device is to distribute map data from a server using a communication device. Because the method using a communication device increases communication costs and update processing time depending on the amount of data distributed, research is underway into technologies for reducing the amount of data distributed. For example, Patent Literature 1 describes a technology in which roads are categorized into "expressways," "general roads," and "minor streets" and then distributed. It distributes nationwide update data for "expressways," while narrowing the distribution target to update data for "general roads" and "minor streets" for a distribution area centered on the destination.

[0003] JP 2012-181040 A

[0004] As mentioned above, Patent Document 1 describes a method for reducing the amount of data related to "general roads" and "minor streets." However, Patent Document 1 states that "expressways" are distributed nationwide, and therefore does not take into consideration reducing the amount of data required for updating expressways. As a result, Patent Document 1 still has problems, such as an increase in data volume due to the distribution of map data unrelated to the route when updating a map along the route, an increase in communication costs due to the increase in data volume, and a deterioration in performance of the map update process.

[0005] Therefore, an object of the present invention is to provide a map distribution device that, when updating map data along a route, distributes update data that is limited to the required range depending on the type of road in the route information, thereby reducing the amount of distributed data, reducing communication costs, and preventing performance degradation in the map update process; an in-vehicle device that receives map data from the map distribution device; and a map distribution system that is configured so that the map distribution device and the in-vehicle device can communicate with each other.

[0006] In order to achieve the above object, the map distribution device of the present invention includes a map recording unit that records map data, a route acquisition unit that acquires route information on the map data, and a map distribution unit that distributes map data divided using different partitioning methods based on the route information.

[0007] The in-vehicle device according to the present invention includes a map acquisition unit that acquires map data and a map recording unit that records the map data, and the map acquisition unit acquires the map data, which is divided using different division methods based on route information on the map data, from a map distribution device.

[0008] Furthermore, a map distribution system according to the present invention includes a map distribution device including a map recording unit that records map data, a route acquisition unit that acquires route information on the map data, and a map distribution unit that distributes map data segmented using different partitioning methods based on the route information to a vehicle; and an in-vehicle device including a map acquisition unit that acquires the map data segmented using different partitioning methods based on the route information from the map distribution device, and a map recording unit that records the map data acquired by the map acquisition unit.

[0009] According to the present invention, for example, map data based on one of the section management methods is distributed depending on the type of road (expressway or ordinary road) in the route information, thereby reducing the amount of data distributed. Furthermore, by not distributing map data that is not related to the route information, communication costs can be reduced and performance degradation of the map update process can be prevented.

[0010] Problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments.

[0011] 1 is a block diagram showing the configuration of a map distribution system according to an embodiment; FIG. 2 is a diagram showing a map data management method; FIG. 3 is a diagram showing an example of division of a route map at an interchange; FIG. 4 is a diagram showing an example of division of a route map at a junction; FIG. 5 is a diagram showing a method of selecting a route map based on route information; FIG. 6 is a diagram showing a method of distributing map data of one of the section management methods depending on the type of road in the route information; FIG. 7 is a diagram comparing the amount of distributed data visually expressed in terms of the number of roads in one mesh; FIG. 8 is a diagram showing associated data that associates map data of different section methods; FIG. 9 is a diagram showing search data for searching route maps by area; and FIG. 10 is a diagram showing a flow for acquiring map data along a route.

[0012] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0013] FIG. 1 is a diagram illustrating an example of the configuration of a map distribution system 1 according to an embodiment.

[0014] The map distribution system 1 of this embodiment is composed of a map distribution server 2, a vehicle 3, and a network 4. The map distribution server 2 and the vehicle 3 are configured to be able to send and receive map information via the network 4.

[0015] The map distribution device 10 included in the map distribution server 2 includes a map recording unit 110 that records map data, a route acquisition unit 120 that acquires route information on the map data, and a map distribution unit 130 that distributes map data based on the route information.

[0016] FIG. 2 is a diagram showing the contents of the map data managed by the map recording unit 110. As shown in FIG.

[0017] The map recording unit 110 manages map data using different division methods depending on the type of road. As shown in Figure 2, for expressways, a route map 21 is recorded for each group of roads (hereinafter referred to as "route") that follow a road. For general roads, a mesh map 22 is recorded for each area divided into a fixed grid (hereinafter referred to as "mesh").

[0018] The mesh map 112 (FIG. 1) manages map data such as road shapes and road attributes for each mesh. The size of the mesh is arbitrary.

[0019] The route map 111 (FIG. 1) manages map data such as road shapes and road attributes for each route.

[0020] The route map 111 is recorded by dividing map data at branching points on the route. For example, the map data is divided at interchanges, junctions, etc. Parking areas are separated from the main road, but are not divided because the road always returns to the main road.

[0021] 3 is a diagram showing a case where the route map 111 is divided at interchanges. Route map data 31 includes data on main road sections and branch roads. Route map data 32 includes data on main road sections and merging roads.

[0022] Autonomous driving assistance devices and the like require map data not only of the road on which the vehicle is currently traveling but also of surrounding roads on which the vehicle may travel, so these requirements can be met by managing the merging and branching roads that run parallel to the main road as a single data set.

[0023] 4 is a diagram showing a case where the route map 111 is divided at junctions. Route map data 41 includes data on the main line portion and data on each branch road. Route map data 42, route map data 43, and route map data 44 include data on the main line portion and data on each merging road.

[0024] Like interchanges, junctions also manage the main line and the merging and branching roads that run parallel to it with a single piece of data.

[0025] 5 is a diagram showing a method for selecting a route map based on route information. In FIG. 5, for example, if the route information indicates entering an expressway at entrance BB, passing through CC, and exiting the expressway at exit DD, route map data 52 and route map data 53 are acquired as route map data for the section corresponding to the route information (route map data 51, 54, 55, and 56 are not acquired). By dividing the route map data into units where the route branches, it is possible to acquire only the route map data required according to the route information.

[0026] The route acquisition unit 120 acquires route information from map data. The route information includes at least an attribute for identifying whether the road type is an expressway or an ordinary road.

[0027] The map distribution unit 130 acquires map data of different division methods from the map recording unit 110 according to the type of road based on the route information acquired from the route acquisition unit 120, and distributes the map data.

[0028] When the type of road in the route information is an expressway section, the map distribution unit 130 distributes a route map 111 in a division system that divides the route into sections managed along the route.

[0029] When the type of road in the route information is a general road section, the map distribution unit 130 distributes a mesh map 112 in a division system in which the road is divided into predetermined areas and managed in mesh units.

[0030] Fig. 6 shows a method for distributing map data using one of the section management methods based on the type of road in the route information. In the example shown in Fig. 6, a conventional method 60 distributes mesh-based map data (mesh map data) for all sections, regardless of the type of road in the route information.

[0031] In the method 70 of this embodiment, for sections of ordinary roads, mesh map data 61, mesh map data 62, mesh map data 63, mesh map data 64, and mesh map data 65 are distributed. For sections of expressways, mesh map data 69 is not distributed, but route map data 66, route map data 67, and route map data 68 are distributed.

[0032] Depending on the type of road in the route information, map data (route map 111 or mesh map 112) of one of the section management methods is distributed, so the amount of data to be distributed can be reduced.

[0033] 7 is a diagram visually comparing the amount of data delivered by a conventional technology method 71 and a method according to this embodiment 72, expressed in terms of the number of roads within one mesh. In the example shown in FIG. 6, mesh map data 69 is the portion that changes from the conventional technology method to the method according to this embodiment, and a comparison of the amount of data delivered by mesh map data 69 is shown.

[0034] As shown in FIG. 7, in the conventional technique method 71, the distribution targets are expressway sections as well as general roads within a mesh, whereas in the method 72 of this embodiment, only expressway sections are the distribution target, thereby reducing the amount of data to be distributed.

[0035] The extent of the effect of reducing the amount of data varies depending on how many public roads are recorded within the mesh, but in this embodiment, the amount of data distributed does not increase because data on public roads is excluded from the state in which all data is targeted as in the conventional technology method.

[0036] Furthermore, in the expressway section, map data for the upbound direction and map data for the downbound direction are managed separately as the route map 111, and therefore either the upbound direction or the downbound direction is selected and distributed according to the route information, thereby reducing the amount of data distributed in the expressway section.

[0037] Next, the related data 113 recorded in the map recording unit 110 of FIG. 1 will be described.

[0038] Figure 8 shows the distribution range of related data that associates map data of different section methods. It is common to prepare data that associates map data of different management methods, but the amount of data can be reduced by narrowing the range of related data distribution. In Figure 8, only a ramp section 81 where an ordinary road connects to an expressway is targeted for distribution.

[0039] Next, the search data 114 recorded in the map recording unit 110 of FIG. 1 will be described.

[0040] 9 is a diagram showing search data for searching the route map 111 by area. When acquiring map data around a vehicle, an automatic driving assistance device or the like searches for the surrounding map data based on the vehicle's coordinate information. Because the mesh map 112 is managed in a mesh-like grid with a fixed interval, it is possible to search for the mesh based on the vehicle's coordinate information.

[0041] The route map 111 can obtain the surrounding route map by obtaining coordinates from the shape data included in each route map data 96 and comparing them with the vehicle's coordinate information, but this method is inefficient because it requires processing for all route map data 96.

[0042] Therefore, the map distribution unit 130 distributes search data 93 for acquiring a route map in units of areas.

[0043] The search data 93 is managed in area units (91, 92) of any size. The size of the managed area of ​​the search data 93 may be the same as or different from the size of the managed area (mesh) of the mesh map 112, for example. Because the areas are separated at regular intervals, an area can be identified from any coordinates by proportional calculation. Techniques such as mesh codes and tile IDs are available for determining an area from coordinates. The search data 94 for each area records management information 95 of the route map data present within the area. The management information 95 holds only index information for referencing route map data 96. For example, route map data 97 existing across areas 91 and 92 aggregates large amounts of route map data, such as shape data and attribute data, into one, and the route map data is referenced from multiple areas using index information (98).

[0044] In other words, the search data 93 associates a predetermined area defined by map data of one division method (for example, a division method based on meshes (areas) in which areas are divided and managed) with map data of another division method included within each predetermined area (for example, a division method based on routes in which areas are managed along routes), and is used when searching for map data of one division method based on map data of the other division method. The map distribution unit 130 distributes this search data 93 in order to obtain map data (route maps) of the other division method on an area-by-area basis.

[0045] Next, the map management device 20 of the vehicle 3, which is an on-board device, will be described.

[0046] The map management device 20 included in the vehicle 3 includes a map recording unit 210 that records map data, a map acquisition unit 220 that acquires the map data, and a location information acquisition unit 230 that acquires location information of the vehicle 3.

[0047] The map recording unit 210 manages map data using different division methods depending on the type of road, similar to the map recording unit 110 of the map distribution device 10. As shown in Fig. 2, for expressways, route maps 211 are recorded in units of groups of roads that follow the road. For general roads, mesh maps 212 are recorded in units of areas divided into a fixed grid.

[0048] The map recording unit 210 also stores association data 213 that associates map data of different division management methods with each other, and search data 214 for searching route maps in area units.

[0049] The map acquisition unit 220 receives map data (i.e., map data divided using different division methods based on route information on the map data) from the map distribution server 2 via the network 4 and updates the map data in the map recording unit 210 of the vehicle 3.

[0050] The location information acquisition unit 230 acquires the current location of the vehicle 3 and location information of the departure point and destination.

[0051] FIG. 10 is a diagram showing a flow of acquiring map data along a route from the map distribution server 2 in the vehicle 3.

[0052] The map acquisition unit 220 of the map management device 20 of the vehicle 3 acquires the location information of the departure point and the destination from the location information acquisition unit 230 (S101).

[0053] Next, the map acquisition unit 220 transmits the location information to the map distribution device 10 of the map distribution server 2 via the network 4 (S102).

[0054] Next, the processing flow of the map distribution device 10 of the map distribution server 2 is shown in S103.

[0055] The route acquisition unit 120 of the map distribution device 10 of the map distribution server 2 acquires route information from the received location information (S104).

[0056] The map distribution unit 130 acquires the route map 111, the mesh map 112, the related data 113, and the search data 114 from the map recording unit 110 based on the route information (S105).

[0057] Next, the map distribution unit 130 transmits the acquired map data to the map management device 20 of the vehicle 3 via the network 4 (S106).

[0058] The map acquisition unit 220 of the map management device 20 of the vehicle 3 updates the route map 211, mesh map 212, related data 213, and search data 214 recorded in the map recording unit 210 with the received map data (S107).

[0059] Next, a flow for acquiring route map data of the area around the vehicle using the search data in the vehicle 3 will be described with reference to FIG.

[0060] The area 91 is identified by calculating the area divided at regular intervals from the coordinates of the vehicle.

[0061] Next, search data 94 in area 91 is identified from search data 93 .

[0062] Next, route management information is acquired from the search data 94.

[0063] Next, the route map data 96 is referenced from the route management information index.

[0064] As described above, the map distribution device 10 of this embodiment includes the map recording unit 110 that records map data, the route acquisition unit 120 that acquires route information on the map data, and the map distribution unit 130 that distributes map data (route map 111, mesh map 112) that are partitioned using different partitioning methods based on the route information.

[0065] The map distribution unit 130 distributes different block-based map data (route map 111, mesh map 112) depending on the type of road in the route information.

[0066] The map recording unit 110 manages map data (route map 111, mesh map 112, etc.) in different division methods depending on the type of road.

[0067] When the road is an expressway section, the map distribution unit 130 distributes map data (route map 111) in a division system for each route managed along the route.

[0068] When the road is a general road section, the map distribution unit 130 distributes map data (mesh map 112) in a division system in which the road is divided into predetermined areas and managed in units of meshes.

[0069] The map distribution unit 130 distributes association data 113 that associates the map data (route map 111, mesh map 112) of the different division methods with each other in a predetermined section.

[0070] The map distribution unit 130 distributes search data 114 that associates predetermined areas defined by map data of a first division method with map data of a second division method included in each predetermined area, and is used when searching for map data of the second division method based on the map data of the first division method.

[0071] The first division method is a division method in which a predetermined area is divided and managed in mesh (area) units, and the second division method is a division method in which a route is managed along the route.

[0072] The map management device 20, which is an in-vehicle device in this embodiment, includes a map acquisition unit 220 that acquires map data and a map recording unit 210 that records the map data. The map acquisition unit 220 acquires the map data (route map 111, mesh map 112) that are divided using different division methods based on route information on the map data from the map distribution device 10.

[0073] The map distribution system 1 of the present embodiment also includes a map distribution device 10 that includes a map recording unit 110 that records map data, a route acquisition unit 120 that acquires route information on the map data, and a map distribution unit 130 that distributes map data (route map 111, mesh map 112) that is segmented using different segmentation methods based on the route information to a vehicle; and a map management device 20 that is an in-vehicle device that includes a map acquisition unit 220 that acquires the map data (route map 111, mesh map 112) that is segmented using different segmentation methods based on the route information from the map distribution device 10, and a map recording unit 210 that records the map data acquired by the map acquisition unit 220.

[0074] That is, the map distribution system 1 (the map distribution device 10) of this embodiment manages map data using different section methods depending on the road type (expressway, general road) in the route information, and distributes map data using different section methods depending on the road type in the route information.When the road type in the route information is a highway section, map data using a route-by-route division method managed along the route is distributed.When the road type in the route information is a general road section, map data using a mesh-by-mesh division method managed by dividing the road into specified areas is distributed.

[0075] In other words, the map distribution system 1 (the map distribution device 10) of this embodiment manages map data using different section management methods depending on the type of road (expressway, general road) included in the route information, and in along-route updates, expressway sections are distributed in line units, and general road sections are distributed in mesh units.

[0076] According to this embodiment, for example, map data of one of the section management methods is distributed depending on the type of road (expressway or ordinary road) in the route information, which reduces the amount of data distributed. Furthermore, by not distributing map data that is not related to the route information, communication costs can be reduced and performance degradation of the map update process can be prevented.

[0077] It should be noted that the present invention is not limited to the above-described embodiment, and includes various modifications. For example, the above-described embodiment has been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to an embodiment having all of the described configurations.

[0078] Furthermore, the above-described configurations, functions, processing units, processing means, etc. may be partially or entirely implemented in hardware, for example, by designing them as integrated circuits. The above-described configurations, functions, etc. may also be implemented in software, with a processor interpreting and executing a program that implements each function. Information such as the programs, tables, and files that implement each function can be stored in a memory, a recording device such as a hard disk or SSD (Solid State Drive), or a recording medium such as an IC card, SD card, or DVD.

[0079] In addition, the control lines and information lines shown are those that are considered necessary for the explanation, and do not necessarily show all the control lines and information lines in the product. In reality, it can be assumed that almost all components are interconnected.

[0080] REFERENCE SIGNS LIST 1 Map distribution system, 2 Map distribution server, 3 Vehicle, 4 Network, 10 Map distribution device, 110 Map recording unit, 111 Route map, 112 Mesh map, 113 Associated data, 114 Search data, 120 Route acquisition unit, 130 Map distribution unit, 20 Map management device (on-vehicle device), 210 Map recording unit, 211 Route map, 212 Mesh map, 213 Associated data, 214 Search data, 220 Map acquisition unit, 230 Location information acquisition unit

Claims

1. A map distribution device comprising: a map recording unit that records map data; a route acquisition unit that acquires route information on the map data; and a map distribution unit that distributes map data divided in different partitioning methods based on the route information.

2. A map distribution device according to claim 1, wherein the map distribution unit distributes map data in different block formats according to the type of road in the route information.

3. A map distribution device according to claim 1, wherein the map recording unit manages map data in different partitioning methods according to the type of road.

4. A map distribution device according to claim 2, wherein the map distribution unit distributes map data in a route-by-route division system managed along the route when the road is an expressway section.

5. A map distribution device according to claim 2, wherein the map distribution unit distributes map data in a mesh-based division system in which the road is divided into predetermined areas and managed when the road is a general road section.

6. A map distribution device according to claim 1, wherein the map distribution unit distributes association data that associates the map data of the different partitioning methods with each other in a predetermined section.

7. A map distribution device as described in claim 1, wherein the map distribution unit associates predetermined ranges defined by map data of a first division method with map data of a second division method included in each of the predetermined ranges, and distributes search data used when searching for map data of the second division method based on the map data of the first division method.

8. A map distribution device as described in claim 7, wherein the first division method is a mesh-based division method in which a predetermined area is divided and managed, and the second division method is a route-based division method in which a route is managed along the route.

9. An in-vehicle device comprising: a map acquisition unit that acquires map data; and a map recording unit that records the map data, wherein the map acquisition unit acquires the map data, the map data being divided in different partitioning methods based on route information on the map data, from a map distribution device.

10. A map distribution system including a map distribution device including a map recording unit that records map data, a route acquisition unit that acquires route information on the map data, and a map distribution unit that distributes map data divided using different partitioning methods based on the route information to a vehicle; and an in-vehicle device including a map acquisition unit that acquires the map data divided using different partitioning methods based on the route information from the map distribution device, and a map recording unit that records the map data acquired by the map acquisition unit.