JP2003337027A - Method and program for map data processing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a map-data processing method in which a part of large- capacity map data provided by a recording medium or the like is updated with satisfactory efficiency and in which new data and old data are used with satisfactory efficiency so as to have a matching property, to provide a map-data processing program and to provide a map-data processing unit for realizing the map-data processing method. <P>SOLUTION: Whole-country map data is divided into a plurality of blocks, each block is divided into a plurality of meshes, each block has whole-mesh control information, and a part of the whole-country map data is updated in units of meshes while the whole-mesh control information is being used. At this time, the whole-mesh control information in the recording medium 2 is transferred to a nonvolatile memory 12 inside a navigation system 1, and its content is updated sequentially according to its update. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a map data processing method and a map data processing program.

[0002]

2. Description of the Related Art Conventionally, map data such as road maps used in navigation devices are stored on a CD-ROM or a DVD-ROM.
It was provided by a recording medium such as a ROM. In addition, map data is also provided to a vehicle-mounted navigation device using communication.

[0003]

However, there is provided a mechanism for efficiently updating a part of the large-capacity map data provided by a recording medium or the like and using the old and new map data in an efficient and consistent manner. Didn't.

The present invention is a map data processing method and a map data processing method that can efficiently update a part of large-capacity map data provided on a recording medium or the like and can efficiently use old and new map data with consistency. It is to provide a program and a map data processing device that realizes the map data processing method.

[0005]

The invention according to claim 1 is applied to a map data processing method in a map data processing device, and the map data divided into a plurality and the map data divided into a plurality of are recorded media. The management information of the map data indicating whether or not it is stored at the position is read into the nonvolatile memory in the map data processing device from the recording medium, and a part of the map data is updated in divided units. When the update data is obtained, in the management information of the nonvolatile memory, a part of the management information corresponding to the update data is changed to indicate the position where the update data is stored, and based on the management information of the nonvolatile memory, The map data is accessed. The invention of claim 2 is applied to a map data processing program executed for processing map data in a map data processing device, and the map data divided into a plurality and the map data divided into a plurality are recorded media. The management information of the map data indicating whether or not it is stored at the position is read into the nonvolatile memory in the map data processing device from the recording medium, and a part of the map data is updated in divided units. When the update data is obtained, in the management information of the nonvolatile memory, a part of the management information corresponding to the update data is changed to indicate the position where the update data is stored, and based on the management information of the nonvolatile memory, Accessing map data is executed by a map data processing device. The invention according to claim 3 is applied to a map data processing device for processing map data, and a map indicating which position of the recording medium the map data divided into a plurality and the map data divided into a plurality are stored in. Recording medium drive means for mounting the recording medium in which data management information is stored, non-volatile memory for reading the management information from the recording medium and storing it, and updating for updating a part of the map data in divided units. When the update data acquisition unit that acquires the data and the update data acquisition unit acquires the update data, a part of the management information corresponding to the update data in the management information of the nonvolatile memory indicates the position where the update data is stored. And the control means for accessing the map data based on the management information of the nonvolatile memory. The invention of claim 4 is applied to a map data processing method in a map data processing device,
A map data processing device is equipped with the recording medium storing the map data divided into a plurality of pieces and the management information of the map data indicating at which position of the recording medium the map data divided into a plurality of pieces are stored. The identification information indicating that the management information of the map data used by the map data processing device is stored in the recording medium is stored in the first non-volatile memory as the initial value, and the data is divided. When the update data for updating a part of the map data is acquired, the acquired update data is stored in the second non-volatile memory, the management information of the map data is acquired from the recording medium, and the management corresponding to the update data is performed. Part of the information is changed to indicate the position of the second non-volatile memory in which the update data is stored and stored in the third non-volatile memory, and the identification information stored in the first non-volatile memory When the map data management information is changed to identification information indicating that the map data is stored in the third non-volatile memory and the map data is accessed, the first non-volatile memory is accessed and the map data management information is recorded. When the identification information indicating whether the map data is stored in the medium or the third non-volatile memory is obtained and it is determined that the map data management information is stored in the recording medium, the map data management information is read from the recording medium. When it is determined that the map data management information is stored in the third non-volatile memory, the map data management information is acquired from the third non-volatile memory, and the acquired map data management information is added to the acquired map data management information. Based on this, the map data is accessed. The invention of claim 5 is applied to a map data processing program executed for processing map data in a map data processing device,
A map data processing device is equipped with the recording medium storing the map data divided into a plurality of pieces and the management information of the map data indicating at which position of the recording medium the map data divided into a plurality of pieces are stored. When the update data for recognizing that the map data is stored, the identification information indicating that the map data is stored in the recording medium is stored in the first nonvolatile memory, and a part of the map data is updated in divided units, The second non-volatile memory in which the acquired update data is stored in the second non-volatile memory, the management information of the map data is acquired from the recording medium, and a part of the management information corresponding to the update data is stored in the second non-volatile memory. Stored in the third non-volatile memory after being changed to indicate the position of, and the management information of the map data is stored in the third non-volatile memory as the identification information stored in the first non-volatile memory. When changing the identification information shown and accessing the map data, the first non-volatile memory is accessed to identify whether the management information of the map data is stored in the recording medium or the third non-volatile memory. When the information is acquired and it is determined that the map data management information is stored in the recording medium, the map data management information is acquired from the recording medium, and the map data management information is stored in the third nonvolatile memory. When it is determined that the map data processing device acquires the management information of the map data from the third non-volatile memory and accesses the map data based on the acquired management information of the map data. is there. The invention according to claim 6 is applied to a map data processing device for processing map data, and a map indicating which position of the recording medium the map data divided into a plurality and the map data divided into a plurality are stored in. Recording medium driving means for mounting the recording medium in which data management information is stored, and map information management information used by the map data processing device as an initial value when the recording medium is mounted in the recording medium driving means. A non-volatile memory that stores identification information indicating that is stored in a recording medium, an update data acquisition unit that acquires update data that updates a part of the map data in divided units, and an update data A second non-volatile memory for storing the update data acquired by the acquisition means, and a management information of the map data from the recording medium when the update data acquisition means acquires the update data. Then, a part of the management information corresponding to the update data is changed to indicate the position of the second non-volatile memory in which the update data is stored, and the identification information stored in the first non-volatile memory is changed to the map data. A control means for changing the management information to identification information indicating that the management information is stored in the third non-volatile memory; and a third non-volatile memory for storing the management information of the map data changed by the control means. The control means, when accessing the map data, accesses the first non-volatile memory to obtain identification information as to whether the management information of the map data is stored in the recording medium or the third non-volatile memory. However, when it is determined that the map data management information is stored in the recording medium, the map data management information is acquired from the recording medium, and the map data management information is stored in the third non-volatile memory. When it is determined to have been, to acquire management information of the map data from the third nonvolatile memory, based on the acquired management information of the map data is used to access the map data.
The invention of claim 7 is applied to a method of processing map data in a map data processing device, and indicates which position of a recording medium the map data divided into a plurality and the map data divided into a plurality are stored. Recognizing that the recording medium storing the management information of the map data is installed in the map data processing device, the management information of the map data used by the map data processing device is stored in the recording medium as an initial value. Identification information indicating that the map data is stored in the first non-volatile memory, and recognizes the connection with the second non-volatile memory in which update data for updating a part of the map data in divided units is written. , When the connection with the second non-volatile memory is recognized, the management information of the map data is acquired from the recording medium, and a part of the management information corresponding to the update data is stored in the second nonvolatile memory. Stored in the third non-volatile memory to change to indicate the position of sex memory, identification information stored in the first nonvolatile memory management information of the map data 3
When the map data is changed to the identification information indicating that the map data is stored in the non-volatile memory, the first non-volatile memory is accessed to determine whether the management information of the map data is stored in the recording medium. When it is determined that the management information of the map data is stored in the recording medium, the management information of the map data is acquired from the recording medium and the management information of the map data is acquired. When it is determined that the information is stored in the third nonvolatile memory, the management information of the map data is acquired from the third nonvolatile memory, and based on the acquired management information of the map data,
The map data is accessed. The invention of claim 8 is applied to a map data processing program executed for processing map data in a map data processing device,
A map data processing device is equipped with the recording medium storing the map data divided into a plurality of pieces and the management information of the map data indicating at which position of the recording medium the map data divided into a plurality of pieces are stored. The identification information indicating that the management information of the map data used by the map data processing device is stored in the recording medium is stored in the first non-volatile memory as the initial value, and the data is divided. When the connection with the second non-volatile memory in which the update data for updating a part of the map data is written is recognized and the connection with the second non-volatile memory is recognized, the map data of the map data is recorded from the recording medium. The management information is acquired, a part of the management information corresponding to the update data is changed so as to indicate the position of the second non-volatile memory in which the update data is stored, and is stored in the third non-volatile memory. Volatile The identification information stored in the non-volatile memory is changed to the identification information indicating that the management information of the map data is stored in the third non-volatile memory, and when the map data is accessed, the first non-volatile memory is accessed. Then, the identification information indicating whether the map data management information is stored in the recording medium or the third non-volatile memory is acquired, and it is determined that the map data management information is stored in the recording medium. When the management information of the map data is acquired from the recording medium and it is determined that the management information of the map data is stored in the third nonvolatile memory, the management information of the map data is acquired from the third nonvolatile memory. The map data processing device is made to access the map data based on the acquired management information of the map data. The invention of claim 9 is applied to a map data processing device for processing map data, and a map showing which position of a recording medium the map data divided into a plurality and the map data divided into a plurality are stored in. A recording medium driving means for mounting the recording medium in which data management information is stored;
When the recording medium is mounted on the recording medium drive means, a first nonvolatile storage that stores, as an initial value, identification information indicating that the management information of the map data used by the map data processing device is stored in the recording medium. A memory connecting unit that enables connection between the memory and the second non-volatile memory 12 in which update data for updating a part of the map data in divided units is connected; When it is recognized that the update memory is connected, the management information of the map data is acquired from the recording medium, and a part of the management information corresponding to the update data is moved to the position of the second non-volatile memory where the update data is stored. Control means for changing the identification information stored in the first non-volatile memory to identification information indicating that the management information of the map data is stored in the third non-volatile memory. And a third non-volatile memory for storing management information of the map data changed by control means,
The control means, when accessing the map data, accesses the first non-volatile memory to obtain identification information as to whether the management information of the map data is stored in the recording medium or the third non-volatile memory. When it is determined that the map data management information is stored in the recording medium, the map data management information is acquired from the recording medium, and the map data management information is stored in the third nonvolatile memory. When the determination is made, the management information of the map data is acquired from the third nonvolatile memory, and the map data is accessed based on the acquired management information of the map data.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram for explaining the transfer of map data having the structure of map data according to the present invention. The in-vehicle navigation device 1 includes a CD-ROM and a D-ROM.
Map data, management information, guidance search data, and the like are read from the recording medium 2 such as a VD-ROM. Update data such as map data is provided from the removable memory 3. The removable memory 3 is a replaceable recording medium in which update data and the like are recorded in order to update a part of the map data.

The navigation device 1 can also be connected to a communication device 4 such as a mobile phone. The navigation device 1 can be connected to the internet 5 via the communication device 4 and further connected to the map server 6 via the internet 5. The map server 6 holds old map data to the latest map data in the map database 7, and holds old guide search data to the latest guide search data in the guide search database 8. Therefore,
The map server 6 can provide update data for updating a part of the map data to the navigation device 1 via the Internet 5. The guidance search data is P
It is data that stores position information such as OI and attribute information such as type and name.

The navigation device 1 has a control device 11 and a non-volatile memory 12. The control device 11 is composed of a microprocessor and its peripheral circuits. The non-volatile memory 12 is a non-volatile memory such as a hard disk or a flash memory provided inside the navigation device 1. The non-volatile memory 12 may be any storage device as long as the written data is not erased even when the power of the navigation device 1 is turned off.

The recording medium 2 is temporarily stored in the navigation device 1.
When it is installed in the navigation device 1, it remains installed in the navigation device 1 unless it is replaced with a new recording medium 2. Therefore, the removable memory 3 may be referred to as a fixed medium. The map database 7 and the guidance search database 8 are mother data databases because they have all old and new map data and guidance search data. The map server 6 can use the map database 7 and the guidance search database 8 to prepare the recording medium 2 having initial (pre-update) map data and the like, and the removable memory 3 having update data.

FIG. 2 is a block diagram of the vehicle-mounted navigation device 1. The navigation device 1 is a control device 1
1, non-volatile memory 12, current location detection device 13, DVD
Drive device 14, memory 15, communication interface 1
6, it has a removable memory reading device 17, a monitor 18, and an input device 19.

The current position detection device 13 is a current position detection device for detecting the current position of the vehicle. For example, a direction sensor for detecting the traveling direction of the vehicle, a vehicle speed sensor for detecting the vehicle speed, and a GPS.
(Global Positioning System) A GPS sensor for detecting GPS signals from satellites and the like. DVD drive device 1
Reference numeral 4 is a device that is equipped with the recording medium 2 and reads map data and the like. In the present embodiment, the recording medium 2 is a DVD-
ROM. It may be a CD-ROM or another recording medium.

The memory 15 stores the vehicle position information and the like detected by the current position detection device 13, and the control device 1
This is a memory for storing node information, link information, etc. on the recommended route calculated by 1. Further, it also stores all mesh management information described later. The memory 15 is the control device 11
Is a working area. Communication interface 16
Is an interface for connecting the communication device 4. It is possible to use a mobile phone or connect to the Internet via the communication interface 16. The removable memory reading device 17 is a device that is loaded with the removable memory 3 and can read data from the removable memory 3.

The monitor 18 is a display device for displaying a map, a recommended route, and various kinds of information. The monitor 18 may be integrally provided as a part of the navigation device body, or may be separately provided as a housing. Further, only the monitor 18 may be connected to the main body of the navigation device by a cable or the like and provided at separate positions. The input device 19 is an input device for inputting a destination of the vehicle or the like when searching for a route. It may be a remote control or monitor 1
It may be configured by a touch panel or the like provided on the screen of 8. The control device 11 controls the current location information of the vehicle detected by the current location detection device 13, the recording medium 2 and the non-volatile memory 12.
Various kinds of navigation processing such as road map display, route search, route guidance, etc. are performed using the map data stored in. Various processing programs executed by the control device 11 are incorporated in a ROM (not shown) provided inside the control device 11.

-Structure of Map Data- The data structure of the above-mentioned map data will be described in more detail. Map data is information about the map,
This includes background (for map display) data, locator data, network (for route search) data, guidance data (intersection name, road name, direction name, direction guide facility information, etc.). Background data is data for displaying the background of roads and road maps. The locator data is data used for identifying the current location of the vehicle and map matching. The network data is route search data including branch information that is not directly related to the road shape, and is mainly used when calculating a recommended route (route search). Guidance data is data that consists of names of intersections,
It is used when guiding the recommended route to the driver based on the calculated recommended route.

The map data of this embodiment is managed by the concept of levels, blocks and meshes. In this embodiment, the map data is divided into seven levels with different scales, the level of the most detailed scale is level 0, and the level of the widest area map is level 6. Each level includes map data with different scales, but the target area is the same for each level. That is, if the whole of Japan is targeted, the map data of the whole of Japan having different scales for each level is provided. For example, at level 0, the scale factor is 1/625
0, level 3 scale 1/400000, level 4 scale 1/10000, level 6 scale 1 /
It has map data of 128,000,000 throughout Japan.
That is, there are 7 sets of map data corresponding to levels 0-6.

FIG. 3 shows map data levels, blocks, and
It is a conceptual diagram explaining the relationship of a mesh. Levels 3 and 4 are shown as representatives. Reference numeral 101 indicates a target area of the map data. If the map data of the whole of Japan is handled, the area 101 is a range including the whole of Japan. Both Level 3 and Level 4 target the same range of areas.
In level 3, the area 101 is divided into a plurality of blocks 4 × 4 = 16 and managed. One block 102 is divided into a plurality of meshes 103 and managed. In this embodiment, m × n meshes are used for management. The number of divided meshes between the blocks 102 is the same number m × n at the same level.

At level 4, the area 101 is 2 × 2 = 4.
Are divided into a plurality of blocks 104 and managed. One block 104 is divided into a plurality of meshes 105 and managed. In this embodiment, p × q meshes are used for management. The number of divided meshes between the blocks 104 is the same number p × q at the same level.

The levels 3 and 4 differ in the number of blocks into which the area 101 is divided and the number of meshes into which each block is divided. This is handled by Level 4 which handles a wide area map with a smaller scale (large denominator value) and Level 3 which handles a detailed map with a larger scale (smaller denominator value) than Level 4. This is because the amount of data also differs.
That is, an appropriate division is performed according to the amount of data handled at each level. However, within the same level, the size of one block and the size of one mesh are the same. Note that the number of divided blocks at each level in FIG. 3 is an example, and the number is not necessarily limited to this number.

The names of the blocks and meshes are named for convenience in the present embodiment. Therefore, the names are not necessarily limited to these. The mesh may be called a parcel, the block may be called a first division unit, and the mesh may be called a second division unit. Also,
These blocks and meshes may be called geographically divided units.

FIG. 4 is a diagram showing a structure of all mesh management information 181 and mesh data 182 for managing all meshes in a block. The mesh data 182 is map data provided corresponding to the mesh 103 or the mesh 105 described above. All mesh management information 181
Has management information of all mesh data included in a block, and is provided for each block.

The total number of meshes 183 of the total mesh management information 181 of FIG. 4 is the total number of meshes included in the block. The lower left reference position code 184 stores positional information regarding the latitude and longitude of the lower left position of the block. The number of meshes 185 in the longitude direction is the number of meshes arranged in the east-west longitude direction, and m is entered in the example of level 3 in FIG. The number of meshes 186 in the latitude direction is the number of meshes arranged in the north-south latitude direction, and n is entered in the example of level 3 in FIG. Each mesh management information 187 is information for managing each mesh data 182, and is provided by the number of meshes in the block.

Each mesh data 182 includes in-mesh management information 111, background (for map display) data 112, locator data 113, network (for route calculation) data 114, and guidance data 115. The in-mesh management information 111 and the background (for map display) data 112 are used as basic data, and the locator data 113, network data 114, and guidance data 115 are used as extended data.
Basic data is data that exists at all levels. Extended data is data that exists at a unique level. For example, network data may be level 1, 2,
3 and 4, and locator data and guidance data exist at level 0. Note that address extension data, image data, VICS data, building attribute data, peripheral search data, and the like may be further provided as the extended data.

In this embodiment, the upper limit of the data size of the basic data is set and managed. For example,
The upper limit data size is 32 KB. If the basic data exceeds the upper limit due to the update of map data, the excess is managed as extended data. For example, the initial basic data is 20KB and the extended data is 10K.
Assume that the mesh data 182 of B is updated so that only the basic data is updated to 40 KB.
As the updated data, the basic data is edited so as to fit within 32 KB, and the basic data of 8 KB exceeding 32 KB is managed as extended data. Therefore, the extended data is 18
The size of mesh data 182 is 30K.
It goes from B to 50 KB. Also, the initial basic data is 20
Suppose that the mesh data 182 whose KB and extension data are 10 KB is updated and only basic data is updated to 30 KB. In this case, the upper limit of basic data is 3
Since it does not exceed 2 KB, the increasing basic data of 10 KB is added as it is as basic data. as a result,
Basic data after update is 30 KB, extended data is 10 KB
Therefore, the size of the mesh data 182 changes from 30 KB to 40 KB. As described above, the upper limit of the data size of the basic data is set for the following reason.

In the normal case, the navigation device 1 may be used for many years without adding a memory. Therefore, it is desirable that the map data also has a fixed size in accordance with the performance of the navigation device 1 used for many years.
However, it is usually possible that the amount of map data will increase due to the progress of maintenance of building shape data, the refinement of topographical data, the progress of real estate development on site. Therefore, the structure of the map data according to the present embodiment makes it possible to update the map data in mesh units.

On the other hand, when a new type navigation device is put on the market, the amount of data that can be handled by the program is increased due to an increase in the amount of memory, an increase in processing capacity, etc.
It is usually possible that new functions are added or details can be displayed. In such a case, the updated map data needs to have a structure that can be commonly used by the old navigation device and the new navigation device.

Therefore, in the present embodiment, the basic data size is maintained at a data size that can be handled by the old navigation device, and data exceeding this size is edited so as to be recorded in the extended data. Also, new function data that is not used in the old model should be recorded in the extended data.

The same thing can be said for the contents described above with the expression "old model & new model" when they are replaced with "general purpose & high class" and "portable device & in-vehicle device". That is, the structure of the map data according to the present embodiment can be commonly used for a device having a low processing capacity to a device having a high processing capacity.
Then, map data that is commonly used by a device with a low processing capacity to a device with a high processing capacity is used as basic data. The upper limit size of this basic data is a data size that matches the memory size of the device with the lowest processing capacity. As a result, the map data according to the present embodiment can be commonly used by a device having a low processing capacity to a device having a high processing capacity. As a result, the efficiency of map data management and cost reduction can be achieved.

Since the basic data prepared from the beginning is commonly used by devices having a low processing capacity to devices having a high processing capacity, it can be said that the data has a high priority. In addition, the basic data that is updated and increased includes background data that displays a more detailed map than the basic data that was prepared from the beginning, and low-priority background data that does not cause problems even if it is not displayed on the old model. I can say. Of course, even basic data that is updated and increased can be said to be data having the same priority as the basic data prepared from the beginning as long as the basic data can be managed within the above upper limit value.

In the above, the upper limit of the data size of the mesh data 182 is not specified. However, the upper limit of the data size may be defined for the mesh data 182 due to the memory in the navigation device 1. For example, the upper limit of the mesh data 182 is 128 KB. The upper limit value 32 KB of the basic data and the upper limit value 1 of the mesh data 182 are set.
28 KB may be another value. An appropriate value may be determined in consideration of the performance of the navigation device when the map data is initially specified and the performance improvement expected in the future.

-Management of Map Data by Navigation Device- FIG. 5 is a diagram for explaining how map data is managed by the navigation device 1. Navigation device 1
Can read all mesh management information and map data from the recording medium 2, and further read updated map data from the map server 6 via the removable memory 3 or the Internet 5 to use the latest map data.

In the case of the conventional navigation device, the data is read from only the recording medium such as CD-ROM or DVD-ROM. In the navigation device of the present embodiment, the map data in the recording medium 2 and the updated map data are used in a mixed manner. Therefore, the nonvolatile memory 12 that is a readable / writable medium is included. The non-volatile memory 12 is composed of a non-volatile memory such as a hard disk or a flash memory, and retains data even when the navigation device is powered off. Non-volatile memory 1
2 may be referred to as cache media 12.

The non-volatile memory 12 has block management information 124. The block management information 124 has identification information indicating whether all the mesh management information of the block is on the recording medium 2 or the non-volatile memory 12. As an initial value, all mesh management information of each block is set as being on the recording medium 2. In response to the update of the map data on a mesh-by-mesh basis, all mesh management information 125 of the block having the updated mesh is created in the non-volatile memory 12, and in the block management information 124, all the mesh management information of the block is stored in the non-volatile memory. 12
Set that it is above. The program can determine whether all the mesh management information is on the recording medium 2 or the non-volatile memory 12 by first referring to the block management information 124.

Reference numeral 126 is a memory in the memory 15 of the navigation device, which is an area for storing all mesh management information. Hereinafter referred to as the memory 126. The program determines whether all the mesh management information is on the recording medium 2 or the non-volatile memory 12, then reads the all mesh management information from the corresponding medium, and stores it in the memory 126.
To store. The all-mesh management information 127 read in the memory 126 has mesh management information of mesh 1 to mesh n. The mesh management information 128 has position information 129, storage location 130, offset 131, and size 132 data. The position information 129 is position information represented by latitude and longitude of the mesh, and the storage location 130 is data indicating whether the data is in the recording medium 2 or the nonvolatile memory 12. Offset 131
Is a medium (recording medium 2 or non-volatile memory 12)
The size 132 is data indicating the upper position, and the size 132 is data indicating the size of the map data.

When the map data for each mesh is updated in the removable memory 3, the map data for the corresponding mesh is read into the non-volatile memory 12 and stored as the map data 133. Therefore, based on the contents of the storage location 130, the map data that has not been updated can access the recording medium 2, and the updated map data can access the nonvolatile memory 12.

-Data Structure in Recording Medium- Next, the data in the recording medium 2 will be described. The recording medium 2 has a main data file. FIG. 6 is a diagram for explaining the structure of the main data file. The main data file is
It has all management information 151, stored data information 152, level management information 153, block management information 154, all mesh management information 155, and map data 156.

The total management information 151 has information about the entire data such as format version / revision, data version / revision, media identification information, creation date, creator, and cover area. Stored data information 1
52 describes the type and storage location of the data stored in the recording medium 2. The level management information 153 has information on the hierarchical structure (level structure) of the map data stored in the recording medium 2, the type of extended data given to each level, and the storage position of the block management information. When the map data is updated, the level management information 153 stores the block management information (recording medium 2).
In order to change the nonvolatile memory 12), the nonvolatile memory 12 is copied and used.

The block management information 154 has management information of all mesh management information such as division information of all mesh management information at each level, storage location of all mesh management information, storage location and the like. When the recording medium 2 is mounted on the DVD drive device 14, it is copied to the non-volatile memory 12 and used. The storage locations of all mesh management information are all set in the recording medium 2 as initial values. The block management information 154 is created for each level.

The all mesh management information 155 is stored in block units of individual levels. For example, in FIG. 6, at level 0, there are m blocks and m pieces of all-mesh management information 155. Level 1 to Level 6
The same is true for. All mesh management information 155 is
It has storage locations, positions, sizes, and history information of all meshes existing in one block.

The map data 156 corresponds to data in mesh units. The map data 156 is stored for the total number of meshes of all levels and all blocks stored in the recording medium 2. The structure of map data in mesh units is as shown in FIG. Since the map data in mesh units have different update cycles, the management information and the updated data are managed on the non-volatile memory 12, and the data not updated uses the data on the recording medium 2. For example, in background data, the shape and characters are frequently updated,
Other extended data updates do not occur very often. Therefore, the capacity of the non-volatile memory 12 can be effectively used when the updated data is stored in the non-volatile memory 12. Since the basic / extended data on the map data are managed individually, the in-mesh management information section manages history information, storage location, storage location, and size of each data.

-Data Structure in Nonvolatile Memory- As shown in FIG. 5, the nonvolatile memory 12 has block management information 124, all mesh management information 125, and map data 133. Also shown) and level management information (not shown). The data is stored in a file format, and the stored data information and the level management information are stored as a main management file (not shown). The block management information 124 is stored as a block management file, the all mesh management information 125 is stored as an all mesh management information file, and the map data 133 is stored as a map data file.

-Main Management File-The main management file (not shown) stores the stored data information copied from the recording medium 2 and the level management information. The stored data information is stored in the main data file in the recording medium 2 when the data other than the mesh unit data in the recording medium 2 (for example, guide search data) is updated and stored in the nonvolatile memory 12. It is created by copying the stored data information of. Every time the update data of data other than the data in mesh units is stored in the non-volatile memory 12, the storage location of the corresponding management information is changed from the recording medium 2 to the non-volatile memory 12.
Change to.

Further, the stored data information holds the medium identification information so as to correspond to the recording medium 2 which is the source of the cache information. At startup, this information is compared with the medium identification information in the recording medium 2, and if they match, there is no problem. However, when this information is different (another recording medium is inserted), it is managed by each information on the non-volatile memory 12,
The update data on the non-volatile memory 12 cannot be used because the storage location, position, and size are inconsistent with the recording medium 2. When such a situation occurs, navigation is performed using only the data in the recording medium 2.

The level management information is a copy of the level management information in the recording medium 2 when any mesh of the map data stored in the recording medium 2 is updated and stored in the non-volatile memory 12. Created. Each time the map data is stored in the non-volatile memory 12, the storage location of the block management information of the corresponding level is changed from the recording medium 2 to the non-volatile memory 12. At this time, the position information and size of the block management information are also updated to the values in the non-volatile memory 12.

-Block Management File- The block management file is created by copying the block management information 154 of each level in the recording medium 2 to the non-volatile memory 12 when the recording medium 2 is mounted on the DVD drive device 14. It The storage locations of all mesh management information of each block are all set as the recording medium 2 as initial values. When the map data is updated and stored in the nonvolatile memory 12, the block management information of the level corresponding to the map data to be updated is updated. The storage location of all mesh management information corresponding to the updated map data is changed from the recording medium 2 to the non-volatile memory 12. At this time, the position information and size are also changed to the values in the non-volatile memory 12. The block management file is created for each level. In this case, the file name is created using the level as a key.
As a result, the block management file name need not be described, and the level management information size can be saved.

-All mesh management information file-The all mesh management information file updates the map data of the mesh in the corresponding block for the first time and stores it in the non-volatile memory 12
When all the mesh management information of the block corresponding to the map data in the recording medium 2 is copied, it is created. The storage location of the map data is changed from the recording medium 2 to the non-volatile memory 12. At this time, the location information of the map data,
The size is also updated to the value in the nonvolatile memory 12. After that, when the mesh in the corresponding block is further updated, all mesh management information files of the corresponding block already in the non-volatile memory 12 are updated. The entire mesh management information file is created in block units. At this time, the file name is created using the level and block management information as keys. As a result, it is not necessary to describe all mesh management information file names, and the block management information size can be saved.

-Map Data File-The map data file is created when the map data is updated and stored in the non-volatile memory 12. The unit of creation is the mesh unit. The entire map mesh management information corresponding to the updated map data is created by copying the information in the recording medium 2, and the actual storage location of the basic / extended data,
Only the storage position and size are updated to the values in the non-volatile memory 12. The basic / extended data that has not been updated refers to the data in the recording medium 2. The map data file is created in mesh units. At this time, the file name is created using the level, the block management information, and the all-figure mesh management information as keys. As a result, it is not necessary to describe the map data file name, and the size of the figure management information and block management information can be saved.

FIG. 4 is a diagram showing the data structure of one mesh 103 or mesh 105 in FIG. The mesh data includes in-mesh management information 111, background (for map display) data 112, locator data 113, network (for route calculation) data 114, guidance data 11
It consists of 5. The in-mesh management information 111 and the background (for map display) data 112 are used as basic data, and the locator data 113, network data 114, and guidance data 115 are used as extended data. Basic data is data that exists at all levels. Extended data is data that exists only at a specific level. For example, network data exists only at levels 1, 2, 3, and 4,
Locator data and guidance data exist only in level 0. Note that address extension data, image data, VICS data, building attribute data, peripheral search data, and the like may be further provided as the extended data.

-Regarding Basic / Expanded Data of Map Data-As shown in FIG. 4, the map data includes basic data of the mesh management information 111 and the background (for map display) data 112, the locator data 113, and the network. Data 1
14 and a plurality of extension data of the guidance data 115. The individual data (frames) forming the map data will be described below.

-Intra-mesh management information-The in-mesh management information 111 describes information unique to the map data divided by the mesh and information such as the storage location / position / size of the stored background / extended data. FIG. 7 is a diagram showing the structure of the in-mesh management information 111. The in-mesh management information 111 is the mesh information 16
1, background management information 162, extended data identification information 163,
It is composed of extended data management information 164.

The mesh information 161 stores basic information such as the size of the management information in the mesh and the actual size information of the mesh in the vertical and horizontal directions. The background management information 162 stores management information regarding the background data (data for map display) of this mesh. Specifically, history information, storage location,
The storage location, offset, and size are stored. As the history information, for example, a management number of update information is stored, and a larger value indicates newer data. An identification flag indicating which of the recording medium 2 and the non-volatile memory 12 stores data is stored in the storage location. The storage location describes the storage location of the background data. In the case of the recording medium 2, the offset is from the head of the main data file, and in the case of the nonvolatile memory 12, the offset is from the head of the map data file. The size stores the actual size of the background data.

The background data is managed by further dividing one mesh area into n × m. Therefore, there are n × m pieces of this background management information. The background data is updated by this n ×
The unit is a mesh divided into m.

As described above, the extension data does not have all types of extension data added to all levels. Also,
Even if the information is attachable, it is not attached to all meshes. For example, no mesh data is attached to the mesh of water area only. Therefore, the extension data identification information 163 describes the type of extension data that can be attached to the mesh and the attached state. The extended data management information 164 is arranged in the order specified by this information by the number of extension data that can be given.

The extension data management information 164 stores management information of individual extension data. The management content is the same as the background data. The history information of the extended data is managed in units of extended data.

-Background Data-The background data (data for map display) 112 may be managed in mesh units, but in the present embodiment, one mesh area is further managed by being divided into n × m. . this is,
This is because it is possible to handle data even with a small screen or memory such as a mobile phone. The background data 112 is updated for each divided unit (divided mesh).
The normalized size of the background data is 2 per mesh.
56 × 256 (coordinate value is 0 to 255). One mesh is created by, for example, a 4 × 4 divided mesh. Therefore, the normalized size per mesh is 1021 x 1
It becomes 021. The divided mesh coordinates 255 = 0 of the adjacent divided mesh, and therefore 256 × 4-3 = 1021.

Although the normalized size is smaller than that of other map data, when a background is supposed to be drawn, there is no problem in practical use because only one division mesh is displayed in the area of 320 × 260 at the maximum. Moreover, since the number of bits used for one coordinate can be reduced, the size of the entire data can be reduced.

The background shape is managed by a maximum of 256 layers, and is drawn with a drawing attribute for each layer. In the existing navigation data, the background data is divided into about 16 classes and assigned drawing attributes. However, when there are many types of backgrounds such as city maps, there are not enough classes and color classification cannot be performed well. Therefore, the layer corresponding to the existing class is expanded to 256 layers. The drawing order is the data storage order. In the existing navigation data, all shapes of the same type are continuously stored. For this reason, even if the shapes are the same, shapes with different drawing orders (such as roads under a high-speed viaduct and roads crossing a high-speed road) cannot be displayed correctly, or unnecessary classes are generated. By setting the drawing order of shapes to the data storage order, it is possible to suppress an increase in layers.

In the case of existing navigation data, there are some which share the road shape for display and the road shape for map matching network. This is because the amount of data can be reduced by using the displayed and searched road shapes. In the present embodiment, the storage of the road shape as the background data is switched in level units. The advantage of storing the road shape as the background shape is that when drawing a map,
Maps can be drawn with one access without accessing multiple data groups such as backgrounds, roads, and characters. Also, since the road is good as a background, it is possible to drastically deform and connect, so it is possible to reduce the amount of display data and improve the display speed.

-Locator data-In the locator data, roads are represented by the concept of links, nodes, and link strings. A node is an intersection or a designated point on a road. A link corresponds to a road between nodes, and a link string represents one road by a plurality of links. The locator road data exists at the lowest level 0 of the road map and is used for confirmation of the own vehicle position, acquisition of route coordinates of search results, narrow street search, and the like. The structure of road data as locator data holds the same information as existing navigation data. That is, roads having the same attribute are managed as a set of road data managed in the form of link strings. Road attributes are given to link strings,
It is roughly divided into the things given to links or nodes.

The attributes given to the link string include road type, pay / free classification, infrastructure target attribute, route calculation target flag, and the like. The attributes given to links or nodes include link type, width, cross link information,
The regulation information and the interpolated coordinate information may be used. The normalized coordinates of the locator data are 2048 × 2048. Since the locator data is required to have coordinate accuracy, the locator data has a normalized size different from the background data (1021 × 1021).

A description will be given of how to connect the road with the adjacent mesh when the locator data is updated for each mesh.

The link string data of the locator data is an array of data regarding the nodes existing in the link string. The data regarding the node includes data such as the position coordinate of the node and the link number connected to the node. Normalized coordinate values are used for the position coordinates of the node.

FIG. 8 is a diagram for explaining a case where one road exists across adjacent meshes. The mesh 171 and the mesh 172 are adjacent to each other, and the link 173
One road represented by and link 175 is mesh 171
Exists across the mesh 172. A connection point is provided on the road located at the boundary of the mesh and it is used as a node. In the mesh 171, the node 1 is the node at the connection point.
74 is provided, and in the mesh 172, a node 176 is provided as a node of a connection point.

The data relating to the node stores the position coordinates of the node and the link number connecting in either direction. For example, the node 174 stores the position coordinates of the node 174 and the link number of the link 175 connecting to the right. The node 176 stores the position coordinates of the node 176 and the link number of the link 173 connecting to the left.

If the meshes 171 and 172 have the same history, the connection destination can be specified by the link number to be connected. However, the data of the mesh 172 may be updated and the link number of the link 175 may change. In such a case, the connection destination at the mesh boundary cannot be specified by the link number.

In the present embodiment, when the data is updated, the connection destination is specified by searching whether or not the adjacent meshes have connection points having the same position coordinates. That is, the meshes are connected using the normalized coordinate values of the connection points. The identification of the adjacent mesh itself is performed by using the mesh position information and the like as in the conventional case.

When a new road or the like is added in the field, if only some meshes are updated, there may be no road connected to the mesh side that has not been updated. In such a case, even if the connection destination actually exists,
The data is treated as a dead end. In such a case, it is desirable that the location overnight data of the adjacent mesh be updated. Therefore, when it is possible to connect to the map server 6 via the Internet, an update request for the map data of the adjacent mesh may be automatically transmitted. Alternatively, a display or the like may be displayed to urge the user to send a map data update request.

-Network (for route calculation) data-Network data is a standard level 1 (scale factor 1).
/ 25000) as the lowest layer and stored as extended data in a plurality of higher levels. Network data is represented using the concept of links, nodes, and link strings, like the data for locators. The network data represents connection information of nodes that represent intersections. Each node is
It has adjacent node information that is connected to its own node information. The own node information stores the position coordinates of the own node, and the adjacent node information stores information of all the nodes connected to the own node. The node information of the connected node stores the node number of the node and the link number connected to the node.

The area of one network data is the same as the area of the corresponding map data, and the normalized size of one mesh is 2048 × 2048.

In the structure of network data, the point that is largely different from the existing navigation data is the association of nodes and links between adjacent meshes and levels.
In the case of existing navigation data, the association of the same node between adjacent levels is directly referenced using the index number and offset. On the other hand, in the present embodiment, data is updated in mesh units,
Mix old and new data. Therefore, it is not possible to directly refer to the conventional index number or offset.

When the history information of the network data of the adjacent and upper and lower meshes is the same, the reference using the index number or the like can be performed as in the conventional case. However, if the history information is different, the reference using the index number or the like cannot be performed. Therefore, in the present embodiment, the coordinate value of the connection point of the mesh boundary is used as a key, as with the locator data. The connection points for associating the levels are not necessarily at the mesh boundaries, and nodes existing at both the upper level and the lower level are selected.

When the same node in the adjacent diagram is searched simply using the coordinate value as a key, the coordinate value does not overlap other than the road intersecting on the mesh boundary at the lowest (detailed) level. This is because the node coordinates are defined by the resolution of the lowest level normalized coordinates. Therefore, if the search time is ignored, it is possible to search without fail. However, in the case of higher-level network data, a plurality of nodes may exist at the same coordinates, so it is not possible to search using only simple coordinate values as keys. That is, the two adjacent points defined by different coordinate values at the lower level
Two nodes may be rounded to the same coordinate value as they go up. In such a case, it is not possible to identify which node it is, and it is not possible to search correctly.

Therefore, in the present embodiment, the coordinate value of the lowest level is also used as the key in addition to the coordinate key. As a result, even if the node is a duplicate node in the upper level, the coordinate key of the lowermost layer of the alternate key is different, so that the other party can be searched correctly. Further, since it is possible that duplicate nodes occur at the lowest level, the extended coordinate of 4 bits (value range is 0 to 15) is added to the coordinate value of the lowest layer.

Therefore, the higher-level node normalized coordinates are (Xh, Yh) and the lower-level node normalized coordinates are (Xh, Yh).
l, Yl) and the extended coordinates are α, the normalized coordinates of a node at a higher level are (Xh, Yh) and (Xl, Y
It can be defined as a combination of l) and (α).

As described above, even if the old and new data are mixed, not only the connection between the adjacent meshes but also the connection between the levels can be surely performed. The meshes corresponding to the levels are specified by providing a level correspondence table for each level. The inter-level correspondence table contains information on which node of which mesh of the lower level the node of the level corresponds to. Therefore, the connection points between the levels are associated with each other using this level-to-level correspondence table and the definition of the normalized coordinates described above. By using this level-to-level correspondence table and the above-mentioned normalized coordinates, even if only some of the meshes in the lower level are updated, the roads that have not changed even after the update can be connected to the unupdated upper level data. Can be maintained. In addition, a new road or a road whose shape has changed in the updated mesh cannot be connected to unupdated upper level data, but erroneous connection can be avoided.

The position of the normal mesh is represented by the latitude and longitude of the lower left corner of the mesh. That is, the position information 129 of all mesh management information stores position information corresponding to the latitude and longitude of the lower left corner of the mesh. Further, the normalized coordinates of the mesh have the origin at the lower left corner of the mesh. Therefore, the above-mentioned normalized coordinates correspond to the latitude and longitude corresponding to the position in the map considering the position information of the mesh due to the latitude latitude.
It is represented by dimensional coordinate values. Since these two-dimensional coordinate values are values corresponding to latitude and longitude, it can be said that they are universal values that are not affected by different navigation devices, different standards, etc. That is, the connection between the adjacent meshes and the upper and lower meshes is performed using a universal key.

The normalized coordinates of the higher-level node are not limited to the above definition, but (Xh, Yh) and (Xl, Y
It may be defined as a combination of (1) or a combination of (Xh, Yh) and (α).

In addition, the node normalization coordinates (X
For l, Yl), the coordinates of the lowest level are not necessarily used. Use moderately lower level coordinates. The extended coordinate α is a parameter other than the normalized coordinate, and is, for example, height data of the node. Also,
It may be time data (information) regarding generation and update of data. Further, both height data and time data may be used. The size of the α data may be 4 bits or more.

In addition, in the definition of the above-mentioned normalized coordinates, parameters other than the two-dimensional coordinates (Xh, Yh) at the corresponding level are used, such as the coordinates (Xl, Yl) at other levels or height data (α). is doing. This parameter is 2
Since a method of adding connection information to the dimensional coordinates to describe the connection status between levels is referred to as an inter-level correspondence key in the present embodiment. It may also be called a 2.5-dimensional space key.

In this embodiment, an interlevel correspondence table is provided for each level to correlate nodes between levels. Therefore, the inter-level correspondence key of each level does not necessarily have to include all the lower-level normalized coordinates. For example, it is sufficient to include only the lowest level normalized coordinates. The node normalized coordinates of level 0 are (X0, Y0), the node normalized coordinates of level 1 are (X1, Y1), the node normalized coordinates of level 2 are (X2, Y2), and the node normalized coordinates of level 3 are Assuming that (X3, Y3), the inter-level correspondence key of each level node is expressed as follows. The level 0 corresponding key is (X0, Y0), the level 1 corresponding key is a combination of (X1, Y1) and (X0, Y0), and the level 2 corresponding key is (X2, Y2). And the (X0, Y0) combination, and the level 3 inter-level correspondence key is the (X3, Y3) & (X0, Y0) combination.

-Guide data-The guide data exists only in the map data of the lowest level 0, and is used when guiding the route of the route search result. The guidance data stores information on intersection names, road names, direction names, direction guide information, spot guide information, peripheral target information, road building information, and the like.

-Data update in removable memory-Fig. 9
Is a flowchart for updating map data in the removable memory 3, reading data near the destination, and performing route search. The update data is provided in the removable memory 3. The control of the flowchart of FIG.
Run on.

When the power of the navigation device 1 is turned on, the program according to the flowchart of FIG. 9 is started. In step S1, it is determined whether or not there is updated data.
The determination of the presence / absence of update data is to determine whether or not the removable memory 3 storing the update data is installed. If it is determined that there is update data, the process proceeds to step S2.

In step S 2, the update data in the removable medium 3 is referred to, all mesh management information of the data that needs to be updated with respect to the data in the recording medium 2 is read from the recording medium 2 and written in the nonvolatile memory 12. . In step S3, all mesh management information recorded in the non-volatile memory 12 is rewritten according to the update data. In step S4, the data near the destination is read out based on all the mesh management information recorded in the non-volatile memory 12. As described above, the update data is written in the non-volatile memory 12. However, here, the removable memory 3 is mounted as it is, and the update data is read from the removable memory 3. The map data that has not been updated is read from the recording medium 2.

On the other hand, if it is determined in step S1 that there is no update data, the process proceeds to step S5. In step S5,
It is determined whether there is an update history. Whether or not there is an update history is determined by the block management information 12 in the nonvolatile memory 12.
Access 4 to judge. If it is determined in step S5 that there is an update history, the process proceeds to step S6. Step S
In step 6, the block management information 124 is referred to, and all mesh management information that has been sequentially rewritten so far is read from the nonvolatile memory 12. In step S7, with reference to the block management information 124, all other mesh management information that is not in the non-volatile memory 12 is read from the recording medium 2. In step S8, based on all mesh management information read from the non-volatile memory 12 and the recording medium 2, step S4
Similarly to, the data near the destination is read.

If it is determined in step S5 that there is no update history, the process proceeds to step S9. In step S9, all mesh management information is read from the recording medium 2. Next, in step S10, data in the vicinity of the destination is read from the recording medium 2 based on all the mesh management information read from the recording medium 2.

In step S11, a route search is performed based on the read map data. In the flowchart of FIG. 9, only the data near the destination is read, but the data near the current position is also sequentially read to perform the route search.

-Data update using communication with map server-Fig. 10 shows data near the destination on the Internet 5
6 is a flow chart for performing a route search by reading data from the map server 6 and updating the data through the map server 6, reading data near the present location and near the destination. The update data is provided from the removable memory 3 and the map server 6. The control of the flowchart of FIG. 10 is executed by the control device 11.

When the power of the navigation device 1 is turned on, the program according to the flowchart of FIG. 10 is started. In step S21, initialization processing such as reading all mesh management information is performed. FIG. 11 is a flowchart of this initialization processing.

In step S101 of FIG. 11, it is determined whether or not there is an update history. Whether or not there is an update history is determined by accessing the block management information 124 of the non-volatile memory 12. If it is determined in step S101 that there is an update history, the process proceeds to step S102. In step S102, the block management information 124 is referred to, and all mesh management information that has been sequentially rewritten up to now is read from the non-volatile memory 12. In step S103, the non-volatile memory 12 is referred to by referring to the block management information 124.
All other mesh management information that is not above is read from the recording medium 2. In step S104, data near the current location is read based on all mesh management information read from the nonvolatile memory 12 and the recording medium 2. Next, the process proceeds to step S22 of FIG.

On the other hand, if it is determined in step S101 that there is no update history, the process proceeds to step S105. Step S
At 105, all mesh management information is read from the recording medium 2. In step S106, the data near the current location is read from the recording medium 2 based on the all-mesh management information read from the recording medium 2. Next, step S in FIG.
Proceed to 22.

Returning to FIG. 10, data in the vicinity of the destination is read in after step S22. In step S22, the map server 6 is requested for new data, and if the new data exists, the update data (near the destination) is downloaded by communication. In step S23, the presence or absence of update data is determined. The determination of the presence / absence of update data is to determine whether or not the update data has been sent from the map server 6. If it is determined that there is update data, the process proceeds to step S24 and update processing is performed.

FIG. 12 is a flowchart of this updating process. In step S111 of FIG. 12, it is determined whether or not the data update history near the destination, that is, whether or not the data near the destination has been updated so far. If it is determined that there is an update, the process proceeds to step S112. In step S112,
According to the update data transmitted from the map server 6, all mesh management information already existing in the non-volatile memory 12 is rewritten. Then, it progresses to step S115.

On the other hand, if it is determined in step S111 that there has been no data update near the destination so far, step S11
Go to 3. In step S113, the update data transmitted from the map server 6 is referred to, all mesh management information of data that needs to be updated with respect to the data in the recording medium 2 is read from the recording medium 2 and written in the nonvolatile memory 12.
In step S114, all mesh management information recorded in the non-volatile memory 12 is rewritten according to the update data. Then, it progresses to step S115.

In step S115, the rewritten all mesh management information is read from the non-volatile memory 12 to the memory 126. In step S116, the nonvolatile memory 12
The data near the destination is read based on all the mesh management information read from the. Next, the process proceeds to step S26 in FIG.

In step S23 of FIG. 10, if it is determined that there is no update data transmitted from the map server 6,
It proceeds to step S25. In step S25, the data near the destination is read out from the already existing data. That is, the data is read from the recording medium 2 or from the nonvolatile memory 12 in the case of previously updated data. In step S26, a route search is performed based on the read map data.

-Route Search Using Level Corresponding Keys-
FIG. 13 is a flowchart of a route search using the inter-level correspondence key. In step S31, the road links in the vicinity are respectively specified from the current position information and the destination information. In step S32, the corresponding link of the route calculation data is specified from the obtained road links in the vicinity.
In step S33, it is determined how many layers (levels) to search. Determine how many layers to search according to the distance between the current location and the destination. When the present location and the destination are close to each other, the first-layer route search processing is performed, and when the distance is long, the second-layer route search processing or the third-layer route search processing is performed.

In the route search, the network data of the lowest level (detail side) is usually used near the present location and the destination. Therefore, if the current location and the destination are close to each other, the network data at the lowest level is used. On the other hand, if the current location and the destination are far from each other, an intermediate route is used from the viewpoint of shortening the route search time. The search uses the network data of the upper level (wide area side). Therefore,
The current location and the vicinity of the destination use the network data of the lowest level, and the route search in the middle uses the network data of the upper level. That is, the two-layer route search process or the three-layer route search process is performed.

If it is determined in step S33 that the one-layer route search process is to be performed, the process proceeds to step S34. If it is determined that the two-layer route search process is performed, the process proceeds to step S35. When it is determined that the three-layer route search process is performed, the process proceeds to step S36.

FIG. 14 is a flowchart of the one-layer route search process. In step S201, a new adjacent candidate node is extracted. In this case, adjacent candidate links may be extracted. In step S202,
It is determined whether or not the history information of adjacent meshes required for route search is the same. If it is determined that they are the same, the process proceeds to step S207. If it is determined that they are not the same, step S2 is performed.
Go to 03. In step S207, a normal pointer
The adjacent node is specified by referring to the index.
A normal pointer index is a node number or node ID.

In step S203, it is determined whether or not the own node is the connection point. The connection point is a point for connecting the meshes, and a point located at the mesh boundary is set in the one-layer route search. If it is determined that the own node is not the connection point, the process proceeds to step S207, and if it is determined that the own node is the connection point and the adjacent node is the connection point, the process proceeds to step S204. The case where the own node is not the connection point means that all the adjacent nodes connected to the own node exist in the mesh. When the own node is the connection point, the adjacent node in the adjacent mesh is also the connection point.

In step S204, the level correspondence key between the own node and the adjacent node is referred to. Step S205
Then, it is determined whether or not the level correspondence keys of the own node and the adjacent node match. If it is determined that they match, the process proceeds to step S208, and if it is determined that they do not match, the process proceeds to step S206. The fact that the inter-level correspondence keys of the own node and the adjacent node match means that the adjacent node can be identified, and the node is connected to the node having the same inter-level correspondence key of the adjacent mesh.

In step S206, the own node is processed as a dead end point. That is, the fact that no adjacent node having a matching inter-level correspondence key was found means that the route is interrupted there. Note that step S2
The process of 04 and step S205 has been described on the assumption that there is one connection point between adjacent meshes. But,
There may be multiple connection points at the mesh boundary. In such a case, it is necessary to search which connection point of the adjacent mesh the own node is connected to. Therefore, it is necessary to repeat the processing of steps S204 and S205 for a plurality of connection points of the adjacent mesh until the adjacent nodes can be identified.

If it is determined in step S203 that the own node is not the connection point, the process advances to step S207 to identify an adjacent node by referring to a normal pointer index. This is because the own node and the adjacent node are in the data of one mesh. It should be noted that specifying the adjacent node with reference to the pointer index is simpler and faster than specifying the adjacent node with reference to the inter-level correspondence key.

In step S208, Dijkstra route search processing is performed using the specified node information, and the flow advances to step S209. In step S209,
It is determined whether or not all the route search processes have been completed, and if it is determined that they have not been completed, the process returns to step S201. When it is determined that the search is completed, the one-layer route search process is ended.

FIG. 15 is a flowchart of the two-layer route search process. In step S211, a route search process is performed using lower level meshes of the current position side and the destination side. This is the same process as the one-layer route search process of FIG. In step S212, a process of connecting the lower level node and the upper level node is performed. FIG. 16 is a flowchart showing details of the process of step S212.

In step S221 of FIG. 16, a new upper layer candidate node is extracted from the level correspondence table described above. The level correspondence table is provided on the upper level side (wide area side), and stores information on which node of which mesh on the lower level side (detail side) corresponds to. In step S222, it is determined whether or not the history information of the meshes of the corresponding upper and lower layers is the same. Step S2
If it is determined in step 22 that the history information of the meshes of the corresponding upper and lower layers is different, the process proceeds to step S223.

In step S223, the inter-level correspondence key of the node at the lower level in the inter-level correspondence table is referenced. In step S224, it is determined whether the inter-level correspondence key of the lower-level node in the inter-level correspondence table and the inter-level correspondence key of the node in the lower-level mesh obtained by the search match. When it is determined that they match, the process proceeds to step S227, and when it is determined that they do not match, the process proceeds to step S225. In step S225, the own node at the lower level is processed as a dead point.

On the other hand, if it is determined in step S222 that the corresponding upper layer level and lower layer level mesh history information is the same, the process proceeds to step S226. Step S226
Then, the node ID number is referred to (normal processing) to specify the upper level node. In step S227, the upper layer node corresponding to the specified lower layer node is stored as a candidate. In step S228, it is determined whether or not the process is completed, and if the process is to be continued, the process returns to step S221 to repeat the process. If it is determined that the process is to end, the process of connecting the lower-level node and the upper-level node in FIG.

In step S213, a route search process using an upper level mesh is performed. Step S213
The process of is similar to the one-layer route search process of FIG. 14, and thus its description is omitted. In step S214, the shortest route is obtained from the combination of the candidate routes obtained at the lower level and the upper level.

As described above, when the map data structure and the map data processing method of this embodiment are used,
It has the following effects. (1) Since map data can be updated in mesh units,
When only a part of the map data is updated, it is not necessary to update the entire recording medium such as a DVD-ROM in which the map data is stored. It is possible to set the minimum unit of updating as a mesh unit, that is, as a basic / extended data unit, and it is possible to reduce the communication amount (cost) required for unnecessary data updating. Also, it becomes possible to make the cycle of updating individual basic and extended data different. (2) Since the update data is also provided by communication via the Internet, the latest update data can be provided quickly and at low cost. (3) Since the mesh data is separated into basic data and extended data, common map data can be used even if there is a navigation device that only requires map display or a navigation device that performs route search or guidance processing. It is possible to use. Furthermore, the extended data is also separated according to the type of data. As a result, even when some extension data is needed but other extension data is not needed, it is possible to deal with it by providing update data with the same mechanism. Also,
Background data and other locator data and network data are managed separately. Therefore, when drawing a map, a map can be drawn with one access without accessing a plurality of data groups such as background, roads, and characters. Furthermore, since the road as a background is good, it is possible to drastically deform and connect, and it is hoped that the display data amount will be reduced and the display speed will be improved. (4) Since the mesh data is separated into basic data and extended data, the same map database can be used to provide map data to simple devices such as mobile phones and high-end devices such as car navigation devices. be able to. For example, only basic data is provided for map display and navigation on a mobile phone. The vehicle navigation device is provided with basic data and extended data. (5) Two-dimensional coordinate values corresponding to latitude and longitude are used to connect data between adjacent meshes and between upper and lower levels, so the data update method depends on the model,
It is possible to prevent dependence on the standard. That is, since it can be said that the two-dimensional coordinates corresponding to latitude and longitude are universal data, the data updating method can be standardized by using these data. (6) Since the parameter of the two-dimensional coordinate value plus alpha is used, it is possible to reliably identify the nodes. For example, if the height data is a parameter of plus alpha, even if the road is an elevated connection point,
Can be definitely distinguished. Further, when the coordinate value of the lower layer is used as a parameter of plus alpha, the node or the like can be specified by the resolution of the lower layer. That is, data can be reliably connected even between upper and lower levels having different scales. (7) Since the map data is managed while storing all mesh management information in the non-volatile memory, the update data can be managed easily and reliably. This facilitates the program development of the navigation device. (8) The method of searching for boundary nodes having the same coordinate value from adjacent meshes in order to obtain the connection destination of each boundary node is performed not for all meshes but only for updated meshes. A pointer reference expression search method is used. This makes it possible to minimize the decrease in data processing speed. (9) Since the update data for the whole country is not collectively delivered, but only the area selected by the user is delivered, the reception time can be minimized. In addition, since not all the map data is recorded in the readable and writable mass storage device, a storage capacity capable of recording only the update data requested by the user is sufficient. (10) Further, in the above embodiment, the extended coordinate α is provided as a part of the inter-level correspondence key, and this parameter is used as, for example, height data of the node or time data (information) related to data generation / update. I explained that it was okay. Such extended coordinates α need not be provided to all boundary nodes on the mesh boundary, and may be provided only to some special nodes. For example, it may be provided only to boundary nodes that intersect on the mesh boundary and have the same coordinates. As a result, an increase in data amount and a decrease in data processing speed can be minimized.

In the above embodiment, the control program executed by the control device 11 of the navigation device has been described as an example stored in the ROM, but the contents are not limited to this. The control program and its installation program may be provided on a recording medium such as a DVD. In addition,
The recording medium need not be limited to DVD, but CD-RO
M, magnetic tape, or any other recording medium may be used.

Furthermore, it is also possible to provide those programs via a transmission medium such as a communication line represented by the Internet. That is, the program
It is also possible to convert into a signal on a carrier wave that carries a transmission medium and transmit the signal. When the program is provided on a recording medium or the Internet, it may be provided in the same configuration as that shown in FIG. For example, the recording medium 2 may be a recording medium provided with a program, and the map server 6 may be a server providing an application program.

Further, the above-mentioned control program may be executed on a personal computer to realize a car navigation device. In that case, the current position detection device 13 and the input device 19 may be connected to a predetermined I / O port of the personal computer.

In the above embodiment, an example in which the update data is provided from the removable memory 3 has been described, but the content is not limited to this. Update data on CD-ROM
Alternatively, the recording medium 2 may be written in a DVD-ROM, a DVD-ROM, or the like, and the recording medium 2 may be temporarily replaced and provided.

In the above embodiment, an example of reading the initial map data from the recording medium 2 has been described, but it is not necessary to limit to this content. Receive the initial map data via the Internet 5 and store it in the non-volatile memory 12,
After that, update management may be performed by the method described above.
Further, necessary map data may be received each time via the Internet 5, stored in the non-volatile memory 12 each time, and if there is an update thereafter, update management may be performed by the above-described method.

In the above embodiment, an example of route search is explained as the navigation processing, but it is not necessary to limit to this content. Using the above map data, map display,
Various navigation processes such as route guidance can be performed.

In the above embodiment, the nonvolatile memory 1
2 has been described as an example provided inside the navigation device 1, but it is not necessary to limit to this content. It may be an external storage device connected by a cable or the like.

In the above embodiment, the background data (for map display) is used as the basic data and the network data is used as the extended data, but the contents are not limited to this. For example, network data may be used as basic data. This is the case when map data (network data, etc.) is used for an application that does not display a map. Specifically, we do a route search,
This is the case when it is used in an application in which the direction of travel of a vehicle is guided only by arrows or the like. This is because such a navigation device does not need background (for map display) data. At this time, the network data has the highest priority, and only the network data may be updated in mesh units. That is, the basic data may be, for example, map data of the highest priority type commonly used by a plurality of predetermined models in each application.

Although various embodiments and modifications have been described above, the present invention is not limited to these contents. Other aspects that are conceivable within the scope of the technical idea of the present invention are also included within the scope of the present invention.

[0120]

Since the present invention is configured as described above, it has the following effects. Since the management information of the divided map data is stored in the non-volatile memory to manage the map data, it is possible to easily and surely manage the update data. This facilitates the program development of the navigation device.

[Brief description of drawings]

FIG. 1 is a diagram for explaining exchange of map data having a map data structure of the present invention.

FIG. 2 is a block diagram of a vehicle-mounted navigation device.

FIG. 3 is a conceptual diagram illustrating a relationship among levels of map data, blocks, and meshes.

FIG. 4 is a diagram showing a data configuration of one mesh shown in FIG.

FIG. 5 is a diagram illustrating how map data is managed by the navigation device.

FIG. 6 is a diagram illustrating a configuration of a main data file.

FIG. 7 is a diagram showing a structure of in-mesh management information.

FIG. 8 is a diagram illustrating a case where one road exists across adjacent meshes.

FIG. 9 is a flowchart for updating map data in a removable memory, reading data near a destination, and performing route search.

FIG. 10 is a flowchart for reading data near a destination from a map server via the Internet and updating the data, reading data near the current location and near the destination, and performing route search.

11 is a flowchart of the initialization process in step S21 of FIG.

12 is a flowchart of the update process of step S24 of FIG.

FIG. 13 is a flowchart of a route search using a 2.5-dimensional space key.

FIG. 14 is a flowchart of a one-layer route search process.

FIG. 15 is a flowchart of a two-layer route search process.

16 is a flowchart showing details of the processing in step S212 in FIG.

[Explanation of symbols]

1 Navigation device 2 recording media 3 removable memory 4 Communication device 5 Internet 6 map server 7 map database 8 guidance search database 11 Control device 12 Non-volatile memory 13 Current location detector 14 DVD drive 15 memory 16 Communication interface 17 slots 18 monitors 19 Input device

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G09B 29/00 G09B 29/00 AZ 29/10 29/10 AF term (reference) 2C032 HB03 HB05 HB11 HB22 HC08 HD16 2F029 AA02 AB01 AB07 AC02 AC14 5B075 ND06 UU13 5H180 AA01 BB05 BB13 FF04 FF05 FF13 FF22 FF27 FF32

Claims (9)

[Claims] 1. A map data processing method in a map data processing device, comprising: a map indicating a plurality of divided map data and a map indicating a position on a recording medium where the plurality of divided map data are stored. When the management information is read into the nonvolatile memory in the map data processing device from the recording medium in which the data management information is stored, and update data for updating a part of the map data in the divided units is obtained. In the management information of the non-volatile memory, a part of the management information corresponding to the update data is changed to indicate a position where the update data is stored, based on the management information of the non-volatile memory, A method of processing map data, characterized in that the map data is accessed. 2. A map data processing program executed by a map data processing device for processing map data, wherein any of a plurality of divided map data and one of the plurality of divided map data is a recording medium. The management information of the map data indicating whether or not it is stored in the position is read from the recording medium into the nonvolatile memory in the map data processing device, and a part of the map data is divided into units. In the management information of the non-volatile memory, a part of the management information corresponding to the update data is changed to indicate a position where the update data is stored, A map characterized by causing a map data processing device to execute access to the map data based on the management information in a memory. Data processing program. 3. A map data processing device for processing map data, wherein the map data is divided into a plurality of pieces and the map data indicating at which position of the recording medium the map data is divided. Recording medium drive means for mounting the recording medium in which the management information is stored, a non-volatile memory for reading and storing the management information from the recording medium, and a part of the map data in the divided unit. Update data acquisition means for acquiring update data to be updated, when the update data acquisition means acquires the update data, in the management information of the nonvolatile memory, a part of the management information corresponding to the update data A control unit that changes the location where the update data is stored and that accesses the map data based on the management information of the nonvolatile memory. A map data processing device comprising: a step. 4. A method of processing map data in a map data processing device, comprising: map data divided into a plurality of pieces; and a map indicating at which position of a recording medium the map data divided into a plurality of pieces are stored. Recognizing that the recording medium storing the data management information is installed in the map data processing device, the management information of the map data used by the map data processing device is stored in the recording medium as an initial value. Identification information indicating that the update data is stored in the first non-volatile memory, and when the update data for updating a part of the map data in the divided unit is acquired, the acquired update data is changed to the second Of the management information of the map data stored in the non-volatile memory of the storage medium and a part of the management information corresponding to the update data before the update data is stored. The change to indicate the position of the second non-volatile memory 3
And storing the identification information stored in the first non-volatile memory into identification information indicating that the management information of the map data is stored in the third non-volatile memory. When accessing the map data, the first non-volatile memory is accessed to identify whether the management information of the map data is stored in the recording medium or the third non-volatile memory. And the management information of the map data is stored in the recording medium, the management information of the map data is acquired from the recording medium, and the management information of the map data is stored in the third nonvolatile memory. Management information of the map data is acquired from the third non-volatile memory when it is determined that the map data is stored in the memory, and based on the acquired management information of the map data. A method for processing map data, characterized in that the map data is accessed. 5. A map data processing program executed by a map data processing device for processing map data, wherein any of a plurality of divided map data and the plurality of divided map data is a recording medium. Recognizing that the recording medium storing the management information of the map data indicating whether it is stored in the position is installed in the map data processing device, the map data used by the map data processing device is set as an initial value. When identification information indicating that the management information is stored in the recording medium is stored in the first non-volatile memory, and update data for updating a part of the map data in the divided units is obtained. Storing the acquired update data in a second non-volatile memory, acquiring management information of the map data from the recording medium, and managing information corresponding to the update data. The change some to indicate the position of the said update data is stored second non-volatile memory 3
And storing the identification information stored in the first non-volatile memory into identification information indicating that the management information of the map data is stored in the third non-volatile memory. When accessing the map data, the first non-volatile memory is accessed to identify whether the management information of the map data is stored in the recording medium or the third non-volatile memory. And the management information of the map data is stored in the recording medium, the management information of the map data is acquired from the recording medium, and the management information of the map data is stored in the third nonvolatile memory. Management information of the map data is acquired from the third non-volatile memory when it is determined that the map data is stored in the memory, and based on the acquired management information of the map data. A map data processing program, characterized in that access to the map data is executed in a map data processing device. 6. A map data processing device for processing map data, wherein the map data is divided into a plurality of pieces and the map data indicating which position of the recording medium the map data is divided into. Recording medium drive means for mounting the recording medium in which the management information of the map data is stored, and when the recording medium is mounted in the recording medium drive means, as an initial value, the map data used by the map data processing device A first non-volatile memory for storing identification information indicating that management information is stored in the recording medium; and update data acquisition for acquiring update data for updating a part of the map data in the divided units. Means, a second non-volatile memory for storing the update data acquired by the update data acquisition means, and the update data acquisition means acquiring the update data Acquiring management information of the map data from the recording medium and changing a part of the management information corresponding to the update data to indicate a position of the second non-volatile memory in which the update data is stored, Control means for changing the identification information stored in the first non-volatile memory into identification information indicating that the management information of the map data is stored in the third non-volatile memory; A third non-volatile memory for storing management information of the changed map data, wherein the control means accesses the first non-volatile memory to access the first non-volatile memory when the map data is accessed. Identification information indicating whether the management information is stored in the recording medium or the third non-volatile memory is acquired, and the management information of the map data is stored in the recording medium. When it is determined that the map data is stored, the management information of the map data is acquired from the recording medium, and when it is determined that the management information of the map data is stored in the third nonvolatile memory, the third information is stored. The map data processing apparatus acquires management information of the map data from the non-volatile memory, and accesses the map data based on the acquired management information of the map data. 7. A method for processing map data in a map data processing device, comprising: map data divided into a plurality of pieces; and a map indicating at which position of the recording medium the map data divided into a plurality of pieces are stored. Recognizing that the recording medium storing the data management information is installed in the map data processing device, the management information of the map data used by the map data processing device is stored in the recording medium as an initial value. The identification information indicating that the map data is stored in the first non-volatile memory, and the second non-volatile memory in which the update data for updating a part of the map data in the divided unit is written. When the connection is recognized and the connection with the second non-volatile memory is recognized, the management information of the map data is acquired from the recording medium and a part of the management information corresponding to the update data is acquired. Is changed to indicate the position of the second non-volatile memory in which the update data is stored and stored in the third non-volatile memory, and the identification information stored in the first non-volatile memory is stored in the third non-volatile memory. The management information of the map data is changed to identification information indicating that the map data is stored in the third non-volatile memory, and when the map data is accessed, the first non-volatile memory is accessed to access the map data. When it is determined that the management information of the map data is stored in the recording medium, the identification information indicating whether the management information is stored in the recording medium or the third nonvolatile memory is acquired. When the management information of the map data is acquired from the recording medium and it is determined that the management information of the map data is stored in the third nonvolatile memory, the third nonvolatile memory is used. It acquires management information of the map data from Li, based on the acquired management information of the map data, method of processing map data, wherein the accessing the map data. 8. A map data processing program executed by a map data processing device for processing map data, wherein any of a plurality of divided map data and one of the plurality of divided map data is a recording medium. Recognizing that the recording medium storing the management information of the map data indicating whether it is stored in the position is installed in the map data processing device, the map data used by the map data processing device is set as an initial value. The identification information indicating that the management information is stored in the recording medium is stored in the first nonvolatile memory, and the update data for updating a part of the map data in the divided unit is written. When recognizing the connection with the second non-volatile memory and recognizing the connection with the second non-volatile memory, the management information of the map data is acquired from the recording medium. A part of the management information corresponding to the update data is changed so as to indicate the position of the second non-volatile memory in which the update data is stored, and is stored in the third non-volatile memory. The identification information stored in the first non-volatile memory is changed to the identification information indicating that the management information of the map data is stored in the third non-volatile memory, and when the map data is accessed, the first information is stored. The non-volatile memory is accessed to obtain identification information as to whether the management information of the map data is stored in the recording medium or the third non-volatile memory, and the management information of the map data is recorded in the recording information. When it is determined that the map data is stored in the medium, the map data management information is acquired from the recording medium, and the map data management information is stored in the third non-volatile memory. When it is determined that the map data processing device acquires management information of the map data from the third non-volatile memory and accesses the map data based on the acquired management information of the map data. A map data processing program characterized in that 9. A map data processing device for processing map data, wherein the map data is divided into a plurality of pieces and the map data indicating in which position of the recording medium the divided map data is stored. Recording medium drive means for mounting the recording medium in which the management information of the map data is stored, and when the recording medium is mounted in the recording medium drive means, as an initial value, the map data used by the map data processing device A first non-volatile memory storing identification information indicating that management information is stored in the recording medium; and a first non-volatile memory in which update data for updating a part of the map data in the divided unit is written. And a memory connecting unit that enables connection with the second nonvolatile memory 12, and the recording medium when the second nonvolatile memory is connected to the memory connecting unit. The management information of the map data is acquired from the second data, and a part of the management information corresponding to the update data is stored in the second
Change to show the location of the non-volatile memory of
Control means for changing the identification information stored in the non-volatile memory into identification information indicating that the management information of the map data is stored in the third non-volatile memory, and the control means A third non-volatile memory storing the management information of the map data, wherein the control means, when accessing the map data, accesses the first non-volatile memory to store the management information of the map data. When the identification information indicating whether the map data is stored in the recording medium or the third non-volatile memory is acquired and it is determined that the management information of the map data is stored in the recording medium, the recording medium When the management information of the map data is acquired from the storage device and it is determined that the management information of the map data is stored in the third nonvolatile memory, the third nonvolatile memory is used. Acquires management information of the map data from sexual memory, based on the acquired management information of the map data, the map data processing apparatus, wherein the accessing the map data.