Map data distribution system

• US 20080086262A1
• Filed: 07/27/2007
• Published: 04/10/2008
• Est. Priority Date: 10/05/2006
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Inayoshi, Hirokazu, Asahara, Akinori, Morioka, Michio, Naka, Kenji
• Granted Patent: US 8,005,612 B2
• Time in Patent Office: Days
• US Class Current: 701/208
• CPC Class Codes: G01C 21/3859 Differential updating map data
• CPC Class Codes: G01C 21/3896 Transmission of map data from central databases
• CPC Class Codes: Y10S 707/99932 Access augmentation or optimizing
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

In the case that a road is updated in units of specific areas in order to reduce the amount of communication data, the quality may degrade; for example, a network of roads is disconnected. To solve this problem, alterations to map data are grouped into map update data of the unit in which a network of links to update connects, and an ID is assigned to each map update data. Also, the map update data that may cause disconnection and the map update data that connects the connected components are detected from among all the past map update data, and these map update data are distributed so that they are always applied at the same time.

Claims

1. A map distribution system including a map distribution server that distributes map data and a navigation device that receives said map data, said map distribution server comprising:

a map update data management table that holds map update data including map data to update and IDs of said map update data, by making them correspond to each other;

a memory that stores a per-area map update data management table to hold a specific area of said map data, a version of said specific area, and the ID of said map update data that must have been applied for said specific area, by making them correspond to each other;

a map update data manager that refers to said per-area map update data management table and select said map update data ID required for updating a specific area selected based on an input from said navigation device; and

a communication device that distributes map update data corresponding to said selected map update data ID.

2. The map distribution system according to claim 1, said map update data manager of said map distribution server comprising:

a function of dividing a network, from which road data that is map update data to update, into connected components;

a function of detecting map update data that disconnects or connects said connected components;

a function of making road data between said connected components and dependency attribute of plural or single connection map update data to connect correspond to each other from disconnection map update data that disconnects said connected components, and storing in said memory said connection map update data as dependent map update data that must have been applied for said disconnection map update data; and

a function of distributing, when selected map update data includes disconnection map update data, corresponding said dependent map update data as well.

3. The map distribution system according to claim 2, said map update data manager of said map distribution server comprising:

a function of displaying two map update data on a single display screen; and

a function of making, when an input is received to select said displayed two map update data, either of said two map update data dependent on the other map update data.

4. The map distribution system according to claim 3, said map distribution server comprising:

a function of accepting road selection; and

a function of retrieving update data that updated said road last from the said map update data management table.

5. The map distribution system according to claim 2,

wherein said map update data manager of said map distribution server, as means for distributing map update data that adds a road to connect said connected components when distributing map update data that disconnects connected components in claim 2, adds to the map update data manager described in claim 1, the map update data that adds road data to connect said connected components.

6. The map distribution system according to claim 1,

wherein said navigation device sends to said map distribution server, a map update request containing version number per map data area held by said navigation device;

and

wherein said map update data manager of said map distribution server decides said specific area to update, based on said version number per map data area.

17. The map distribution server according to claim 14,

wherein said map update data manager, as means for distributing map update data that adds a road to connect said connected components when distributing map update data that disconnects connected components in claim 2, adds to the map update data manager describe in claim 1, the map update data that adds road data to connect said connected components.

7. A map distribution management method for a map distribution system including a map distribution server that distributes map data;

and a navigation device that receives said map data,

said map distribution server having;

a memory that stores a map update data management table that holds map update data including map data to update and the ID of said map update data, by making these data correspond to each other;

a per-area map update data management table that holds a specific area of map data, the version of said specific area, and the ID of said map update data that must have been applied for said specific area, by making these data correspond to each other;

a map update data manager; and

a communication device,

said map distribution management method, comprising;

in the map update data manager,

a first step to refer to said per-area map update data management table and a map update data ID required for updating a specific area selected based on an input from said navigation device; and

a second step to distribute from said communication device map update data corresponding to selected map update data ID.

8. The map distribution management method according to claim 7, further comprising:

in said map update data manager of said map distribution server,

a third step to divide a network, from which road data that is map update data to update is removed, into connected components;

a fourth step to detect map update data that disconnects or connects said connected components; and

a fifth step to make road data between said disconnected connected components correspond to dependency attribute of plural or single connection map update data, and store said connection map update data in said memory, as dependent map update data that have been applied for said disconnection map update data,

wherein, if the map update data of said map update ID at said second step includes disconnection map update data, corresponding said dependent map update data is also distributed.

9. The map distribution management method according to claim 8, further comprising:

in said map update data manager of said map distribution server,

a sixth step to display two map update data on a single display screen; and

a seventh step to, when an input to select said displayed two map update data is received, store said selected map update data by making either one dependent on the other.

10. The map distribution management method according to claim 9, comprising:

in said map distribution server,

an eighth step to accept road selection; and

a ninth step to retrieve update data that updated said selected road last from said map update data management table.

11. The map distribution management method according to claim 8, further comprising:

in said map update data manager, as means for distributing map update data that adds a road connecting said connected components when distributing map update data that disconnects connected components in claim 8, a tenth step to add map update data that adds road data connecting said connected components.

12. The map distribution management method according to claim 7, further comprising:

in said map distribution server,

an eleventh step to receive a map update request including a version number in units of areas of a map from said navigation device,

wherein, at said first step, said map update data manager of said map distribution server decides said specific area to update based on said version number per map data area.

13. A map distribution server that is connectable to a navigation device and that distributes map data, comprising:

a map update management table that hold map update data including map data to update and the ID of said map update data, by making them correspond to each other;

a memory that stores a per-area map update data management table that holds a specific area, the version of said specific area, and the ID of said map update data that must have been applied for said specific area, by making them correspond to each other;

a map update data manager that refers to said per-area map update data management table and selects a map update data ID required for updating a specific area selected based on an input from said navigation device; and

a map update data distributor that distributes map update data corresponding to said selected map update data ID.

14. The map distribution server according to claim 13, said map update data manager having:

a function of dividing a network from which road data that is map update data to update into connected components;

a function of detecting map update data that disconnects or connects said connected components;

a function of making road data between said disconnected connected components correspond to dependency attribute of plural or single connection map update data, and store said connection map update data in said memory, as dependent map update data that have been applied for said disconnection map update data; and

a function of, if the map update data of said map update ID at said second step includes disconnection map update data, corresponding said dependent map update data is also distributed

15. The map distribution server according to claim 14, said map update data manager having:

a function of displaying two map update data on a single display screen; and

a function of making, when an input is received to select said displayed two map update data, either of said two map update data dependent on the other map update data.

16. The map distribution server according to claim 15, said map update data manager having:

a function of accepting road selection; and

a function of retrieving update data that updated said selected road last from said map update data management table.

18. The map distribution server according to claim 13,

wherein said map update data manager receives a map update request including a version number in units of areas of map data held by said navigation device, from said navigation device, and decides said specific area to update based on said version number in units of areas of said map data.