JP2018106016A - Map data structure, transmitter, and drive assist system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a map data structure capable of continuing driving assistance or automatic operation free from any problem even when a traveling route includes a point where communication with a server is impossible.SOLUTION: A map data structure includes: plural pieces of mesh data each of which corresponds to areas different from one another; and group information which represents a group of the plural pieces of mesh data to be acquired simultaneously depending on a predetermined geographical structure. When acquiring map data corresponding to a predetermined geographical structure, the plural pieces of mesh data which should be acquired simultaneously are acquired at once based on the group information corresponding thereto.SELECTED DRAWING: Figure 3

Description

  The present invention relates to map data used for driving assistance.

  In recent years, development of map data suitable for driving assistance and automatic driving has been progressing. Map data used for driving assistance and automatic driving has a huge data capacity compared to map data for simple map display used in navigation devices and the like. For this reason, it is assumed that map data for driving support and automatic driving is stored in a server or the like, and the vehicle side is downloaded from the server and used as necessary. Patent Document 1 describes a technique in which map data is stored in a map data distribution server and a necessary portion of map data is downloaded on the terminal device side.

JP 2005-301058 A

  However, depending on the location where the vehicle travels, such as in a tunnel or where the radio wave condition is poor, there may be a case where the map data cannot be received by communicating with the server. In such a case, driving assistance and automatic driving cannot be executed.

  Examples of the problem to be solved by the present invention include the above. An object of the present invention is to make it possible to continue driving support and automatic driving without any trouble even when a place where communication with a server is not included on a travel route.

  The invention according to claim 1 is a map data structure, and a plurality of mesh data corresponding to different areas and a group information indicating a group of a plurality of mesh data corresponding to a predetermined geographical structure and to be acquired simultaneously. It is characterized by including these.

The structure of the driving assistance system which concerns on an Example is shown. The example of the mesh structure of map data is shown. An example of map data is shown. The structure of a driving assistance device is shown. It is a flowchart of a map data acquisition process.

  In a preferred embodiment of the present invention, the map data structure includes a plurality of mesh data corresponding to different areas, group information corresponding to a predetermined geographical structure and indicating a group of a plurality of mesh data to be acquired simultaneously, including.

  The map data structure includes a plurality of mesh data corresponding to different areas and group information corresponding to a predetermined geographical structure and indicating a group of a plurality of mesh data to be acquired at the same time. Therefore, when the vehicle side acquires map data corresponding to a predetermined geographical structure, a plurality of mesh data to be acquired at the same time can be acquired at a time based on the corresponding group information.

  In one aspect of the map data structure described above, the predetermined geographical structure is a structure that is provided for a road and causes an incommunicable state in which the mesh data cannot be received. In a preferred example, the predetermined geographical structure includes at least one of a tunnel, a plurality of continuous tunnels, and an underpass.

  In another aspect of the map data structure, the predetermined geographical structure is a road section having no branches. In a preferred example, the predetermined geographic structure includes at least one of a bridge and a section between adjacent interchanges on a highway or toll road.

  In another preferred embodiment of the present invention, a transmission device includes a storage unit that stores map data having the above-described map data structure, and a transmission unit that transmits the map data to a vehicle. With this transmission device, the map data can be transmitted to the vehicle for use.

  In another preferred embodiment of the present invention, the driving support apparatus includes an acquisition unit that acquires map data having the above-described map data structure, and the acquisition unit acquires a plurality of mesh data indicated by the group information at the same time. To do. Thereby, when acquiring the map data corresponding to a predetermined geographical structure, the driving support device can acquire a plurality of mesh data to be acquired at the same time based on the corresponding group information.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
[System configuration]
FIG. 1 shows a configuration of a driving support system to which the present invention is applied. The driving support system includes a server 10 and a driving support device 20 mounted on the vehicle 3. The server 10 and the driving support device 20 are configured to be capable of wireless communication. In FIG. 1, only one vehicle 3 is shown for convenience of explanation, but a large number of vehicles 3 actually communicate with the server 10.

  The server 10 stores map data, and provides map data on the vicinity of the current position of the vehicle 3 and on the travel route to the driving support device 20 in response to a request from the driving support device 20. In the present embodiment, since driving assistance is performed in consideration of the driving lane of the vehicle 3, in addition to road link data including information for each road, lane link data including information for each lane is prepared as map data. ing. Specifically, the server 10 includes a map database 11 (hereinafter referred to as “DB”) that stores map data including road link data and lane link data.

[Map data]
FIG. 2 shows an example of a mesh structure of map data. Map data is obtained by dividing a certain area into a plurality of meshes. FIG. 2 shows meshes M11 to M45 constituting a certain area. Specifically, a road R1 and a road R2 exist in this area. A tunnel T1 is provided in a part of the road R1. The road R1 branches to the road R2 before the tunnel T1.

  FIG. 3 shows an example of the map data of the area shown in FIG. The map data includes a mesh ID, data, and a group ID. Here, the “mesh ID” is identification information that uniquely indicates each mesh as illustrated in FIG. “Data” is actual data of map data, and includes, for example, the above-described road link data, lane link data, and the like. The “group ID” is identification information that uniquely indicates a group when a plurality of meshes are integrally handled as a group.

  Next, the group will be described in detail. The driving support device 20 mounted on the vehicle 3 basically performs driving support according to the travel route set by the user. For this reason, as the vehicle 3 travels, map data of an area ahead of a predetermined distance on the travel route is always downloaded from the server 10 and stored in the driving support device 20, and driving support is performed using the map data. . For example, as the vehicle 3 travels, the driving support device 20 sequentially downloads 3 km ahead mesh data on the travel route and stores the mesh data in the driving support device 20 (hereinafter also referred to as “normal download”). .)

  However, when the tunnel T1 is on the travel route as shown in FIG. 2, the driving support device 20 cannot communicate with the server 10 in the tunnel T1, and therefore cannot acquire map data. For this reason, in normal downloading, map data ahead cannot be acquired after the vehicle 3 enters the tunnel T1, and driving assistance in the tunnel T1 cannot be performed.

  Therefore, in this embodiment, map data is grouped and downloaded together for a geographical structure such as the tunnel T1 that cannot communicate with the server 10. Specifically, the meshes M14, M23, M24 and M33 to which the tunnel T1 belongs are associated as one group. If the group ID of the group for the tunnel T1 is “T1”, as shown in FIG. 3, the group ID “T1” is assigned to the map data of the meshes M14, M23, M24, and M33. Then, when the vehicle 3 enters the tunnel T1, the driving support device 20 calls the map data of all meshes having the group ID “T1” (hereinafter, “mesh map data” is also simply referred to as “mesh data”). Are collectively downloaded from the server 10. Hereinafter, this method is also referred to as “group download”. In this way, before the vehicle enters the tunnel T1, the driving support device 20 can acquire all the mesh data for the tunnel T1, so that after the vehicle 3 enters the tunnel T1, the driving support of the vehicle 3 can be obtained. Can be continued.

  Even if the mesh data of the meshes M14, M23, M24, and M33 grouped with respect to the tunnel T1 as described above are individually required, they are individually downloaded by the driving support device 20. Used. For example, in FIG. 2, when the vehicle 3 travels on the road R1 from south to north (from the bottom to the top in the figure) and travels in the direction of the road R2 at the fork of the tunnel T1 (ie, does not travel on the tunnel T1) In the case), the driving support device 20 performs driving support by downloading mesh data of the meshes M33, M34, and M35 in order by normal download. That is, the mesh M33 belongs to the group of the tunnel T1, but when the vehicle 3 does not pass through the tunnel T1 and passes through the other road R2 in the mesh M33, the mesh data of the mesh M33 is independent of the group T1. Usually downloaded and used.

  In the above example, a tunnel is cited as a geographical structure to which map data is grouped. However, the present invention is not limited to this. For example, map data may be similarly managed in groups for areas where communication with the server 10 is not possible, such as underpasses and mountain roads. Also, in an area where multiple tunnels are contiguous and the distance between tunnels is short, the map data used in the next tunnel may not be downloaded during the period from exiting the tunnel to entering the next tunnel. is there. In such a case, it is preferable to manage map data by grouping a plurality of continuous tunnels into one group. The same applies to the case where a plurality of underpasses are continuous.

  In the above example, a plurality of mesh data are grouped with respect to a geographical structure that makes communication with the server 10 impossible. However, regardless of the communication environment, there is no road branch on the travel route, When it is certain that the vehicle travels a predetermined section on the travel route, the map data of the section may be managed as a group. For example, for a section of a road that spans a plurality of meshes and does not have a branch, map data may be grouped and managed. Moreover, you may manage map data grouped also about the bridge which straddles a some mesh and does not have a branch in the middle. Furthermore, for a section between adjacent interchanges on a highway or a toll road, a plurality of map data included in the section may be managed as a group.

[Driving support device]
Next, the driving support device 20 will be described in detail.
(Constitution)
FIG. 4 shows the configuration of the driving support device 20. The driving support device 20 is mounted on the vehicle 3. The driving support device 20 may be mounted on the vehicle as a navigation device or the like in addition to being built in the vehicle 3.

  The driving support device 20 includes a communication unit 21, a positioning unit 22, a camera 23, a map DB 24, a storage unit 25, a control unit 26, a display unit 27, and an audio output unit 28. The communication unit 21 communicates with the server 10 by wireless communication. The communication unit 21 is mainly used for downloading map data from the server 10. The positioning unit 22 includes a GPS receiver, a self-supporting positioning device, and the like, and measures the current position of the vehicle 3. The camera 23 is attached to the front part of the vehicle 3 or the vicinity of the windshield in the passenger compartment, and photographs the front of the vehicle 3.

  The map DB 24 stores map data downloaded from the server 10 through the communication unit 21. The storage unit 25 includes a RAM, a ROM, and the like, and stores a program for operating the driving support device 20. In addition, the storage unit 25 provides a working memory for executing various processes.

  The control unit 26 controls the entire driving support device 20. Specifically, the control unit 26 executes map data acquisition processing for downloading map data from the server 10 and driving support processing for supporting driving using the downloaded map data. Information provided to the driver by the driving support process is displayed on the display unit 27 or output as a voice message by the voice output unit 28.

(Map data acquisition process)
Next, a map data acquisition process for acquiring map data from the server 10 will be described. FIG. 5 is a flowchart of the map data acquisition process. This process is repeatedly executed at predetermined time intervals while the vehicle 3 is traveling, mainly by the control unit 26 of the driving support device 20. Further, it is assumed that the travel route to the destination set by the user has already been set as a premise for executing this map data acquisition processing. Moreover, the following example is an example when the map data regarding a tunnel are grouped.

  First, the control unit 26 determines whether or not a tunnel exists on the travel route that has already been set (step S10). If there is no tunnel on the travel route (step S10: No), the process proceeds to step S13. On the other hand, if there is a tunnel on the travel route (step S10: Yes), the control unit 26 determines whether the vehicle 3 has approached the tunnel, or more specifically, whether the distance to the tunnel has become a predetermined distance or less. Is determined (step S11).

  When the vehicle 3 is not approaching the tunnel (step S11: No), the process proceeds to step S13. On the other hand, when the vehicle 3 approaches the tunnel (step S11: Yes), the control unit 26 connects to the server 10 via the communication unit 21 and acquires all mesh data belonging to the group of the tunnel (step S12). ). That is, the control unit 26 performs group download for the tunnel. For example, when the vehicle 3 is approaching the tunnel T1 shown in FIG. 2, the control unit 26 determines the mesh data of meshes M14, M23, M24, and M33 belonging to the group T1 for the tunnel T1 from the map data shown in FIG. Is acquired from the server 10. Then, the process proceeds to step S15.

  On the other hand, when there is no tunnel on the travel route (step S10: No), and when there is a tunnel on the travel route but the vehicle 3 has not yet approached the tunnel (step S11: No), the control unit 26 It is determined whether or not the acquisition timing of forward mesh data on the travel route has arrived (step S13). That is, the control unit 26 determines whether or not it is time to acquire mesh data ahead of a predetermined distance from the current position of the vehicle 3 on the travel route by the above-described normal download (step S13).

  When the acquisition timing of the forward mesh data has not arrived (step S13: No), the process proceeds to step S15. On the other hand, when the acquisition timing of the forward mesh data has arrived (step S13: Yes), the control unit 26 acquires the mesh data from the server 10 (step S14). Then, the process proceeds to step S15.

  In step S15, the control unit 26 determines whether or not the vehicle 3 has arrived at the destination. When the vehicle 3 has not arrived at the destination (step S15: No), the process returns to step S10. On the other hand, when the vehicle 3 arrives at the destination (step S15: Yes), the process ends.

  In the above example, when the map data is grouped for the tunnel, the driving process can be similarly performed when the map data is grouped for another geographical structure. That is, in addition to the tunnel, when the map data is grouped for a geographical structure such as an underpass, a road section without a branch, a bridge, an expressway or an adjacent interchange section of a toll road, the driving support device 20 When these are detected (steps S10 and S11) and the vehicle 3 approaches its geographical structure, all the mesh data belonging to the corresponding group may be acquired (step S12).

[Modification]
In the above embodiment, the map data downloaded from the server 10 is used by the driving support device mounted on the vehicle, but instead, it may be used for automatic driving by the autonomous driving vehicle.

3 Vehicle 10 Server 11 Map DB
20 driving support device 21 communication unit 26 control unit

Claims (7)

A map data structure,
A plurality of mesh data each corresponding to a different area;
Corresponding to a predetermined geographical structure, group information indicating a plurality of groups of mesh data to be acquired simultaneously,
A map data structure containing   2. The map data structure according to claim 1, wherein the predetermined geographical structure is a structure that is provided for a road and causes an incommunicable state in which the mesh data cannot be received. 3.   The map data structure according to claim 2, wherein the predetermined geographical structure includes at least one of a tunnel, a plurality of continuous tunnels, and an underpass.   The map data structure according to claim 1, wherein the predetermined geographical structure is a section of a road having no branch.   The map data structure according to claim 4, wherein the predetermined geographical structure includes at least one of a bridge and a section between adjacent interchanges of a highway or a toll road. A storage unit for storing map data having the map data structure according to any one of claims 1 to 5;
A transmission unit for transmitting the map data to the vehicle;
A transmission device comprising: An acquisition unit that acquires map data having the map data structure according to any one of claims 1 to 5,
The driving support device, wherein the acquiring unit acquires a plurality of mesh data indicated by the group information at the same time.

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