JP2001133273A - Navigation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a navigation system loading a hard disk for transferring and containing map data of a recording medium, being superior in sue convenience and capable of effectively utilizing the memory region. SOLUTION: The CUP 11 of the navigation system judges the drivers own car position based on the sensor output of a sensor 16 and the position detection output of a GPS receiver 17, and transmits the map data of a specific region around the self-car position among the map data recorded in a DVD-ROM 1 into map data memory region 15a in hard disk 15 by way of a RAM 13. In the case necessary map data is contained in the hard disk 15 for indication process to a display 20, the map data is transmitted from the hard disk 15 to an indication controller 21. In the case not contained in the hard disk, the map data are transferred from the DVD-ROM 1 to the indication controller.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation system for performing navigation using map data recorded on a recording medium, and more particularly to a navigation system having a hard disk for storing map data. .

[0002]

2. Description of the Related Art Conventionally, DVD-ROM drives and C
DVD with a D-ROM drive and a recording medium
2. Description of the Related Art Navigation systems that read map data recorded in a ROM or a CD-ROM and perform a navigation operation are widely used. Such a navigation system detects the position of the vehicle when performing a navigation operation, reads map data around the vehicle from a recording medium, and displays a map image created based on the map data together with a mark indicating the position of the vehicle. Display on the screen.

[0003]

By the way, since a recording medium such as a DVD-ROM on which music data and video data are recorded is provided, there is a need to reproduce such a recording medium during operation. However, in the above-described conventional navigation system, it is necessary to always insert the recording medium on which the map data is recorded into the drive during navigation, and it is difficult to use the recording medium for other purposes.

On the other hand, it is also conceivable to mount, for example, a hard disk in the navigation system as a large-capacity and nonvolatile storage means separately from the recording medium. If the entire data such as a DVD-ROM is installed on the hard disk as a whole and the map data is read from the hard disk during the navigation operation,
A DVD-ROM drive or the like can be used for other purposes. In addition, since the hard disk has a high access speed, there is an advantage in that the display screen is drawn at a high speed.

[0005] However, installation work from a recording medium such as a DVD-ROM to a hard disk requires a considerable amount of time, and the operation is troublesome for the user. Also,
For example, a DVD-ROM is a single-sided, single-layer type of 4.7.
The large capacity of 8.7 GB for a single-sided, double-layer type of GB requires a storage area for the hard disk, which is wasteful when the hard disk is used for other purposes. Furthermore, a DV recording map data
When the version of the D-ROM or the like becomes new, it is necessary to repeat the installation each time. Thus, DV
The problem of using a hard disk together with a D-ROM or a CD-ROM is that there are many disadvantages in many points such as usability and cost.

Accordingly, the present invention has been made in view of such a problem, and a hard disk is mounted on a navigation system, necessary map data is automatically transferred to the hard disk, the operability is excellent, and the storage area is effectively used. It aims to provide a navigation system that can be used.

[0007]

According to a first aspect of the present invention, there is provided a navigation system, comprising: a vehicle position detecting means for detecting a vehicle position; and a recording medium on which map data is recorded. First storage means for reading map data, non-volatile second storage means capable of writing and reading map data, and transfer of map data to a predetermined area defined according to the position of the vehicle at a predetermined timing Reading from the recording medium by the first storage means,
Map data transfer means for transferring and storing the map data in the second storage means;
A navigation control unit that controls a navigation operation using the map data stored in the storage unit.

According to the present invention, the navigation system includes first storage means using a recording medium such as a DVD-ROM or CD-ROM, and second storage means such as a hard disk. When map data corresponding to a predetermined area corresponding to the vehicle position detected by the vehicle position detection means is read from the first storage means, the map data is transferred to the second storage means at a predetermined timing. Thereafter, the navigation control unit performs control such as display processing by obtaining map data using both the first storage unit and the second storage unit.

Therefore, once the map data is transferred to the second storage means, the navigation operation is continued even if the recording medium storing the map data is not always set in the first storage means. Also, the more frequently an area travels, the higher the possibility that the map data is stored in the second storage means, and the rational map data transfer is possible.
Thus, the map data can be effectively used, and navigation convenient for the user can be executed.

According to a second aspect of the present invention, in the navigation system according to the first aspect, the second storage means can write and read map data at a higher access speed than the first storage means. It is characterized by being.

According to the present invention, the second storage means stores the first
Since the access speed is higher than that of the storage unit, after the map data is transferred, the map data can be read out from the second storage unit in a shorter time, and a high-speed navigation operation can be performed.

According to a third aspect of the present invention, in the navigation system according to the second aspect, the second storage means is a hard disk drive.

According to the present invention, since the hard disk device is used as the second storage means, the map data can be transferred to the high-speed, large-capacity and highly versatile storage means for use.

According to a fourth aspect of the present invention, in the navigation system according to the first aspect, when the map data necessary for the navigation operation is stored in the second storage means, While the map data stored in the second storage unit is used, if the map data necessary for the navigation operation is readable from the storage medium and is not stored in the second storage unit, the map data is stored in the storage medium. Characterized map data is used.

According to the present invention, the navigation control means determines whether or not the map data is stored in the second storage means during the navigation operation, and uses the map data in the second storage means only when the map data is stored. . Therefore, in the area where the map data has been transferred, the first storage means can be used for other purposes, which is convenient for the user.

According to a fifth aspect of the present invention, in the navigation system according to the first aspect, a map data storage area for storing the transferred map data is set in the second storage means. And

According to the present invention, the predetermined storage capacity of the second storage means is set as the map data storage area, and the transferred map data is stored in the map data storage area.
Therefore, while map data is stored in a part of the second storage means, the other area can be used for storing other data, and the application range of the second storage means can be expanded.

According to a sixth aspect of the present invention, in the navigation system according to the fifth aspect, when the map data is transferred by the map data transfer means when the storage capacity of the map data storage area is exceeded. It is characterized by further comprising a map data deleting means for deleting a part of the map data in the map data storage area according to a predetermined condition.

According to the present invention, the map data is read from the first storage means, and when it is found that the remaining capacity of the map data storage area is small and the storage capacity is exceeded at the time of transfer, the map data is stored according to a predetermined condition. Some of the map data that has already been deleted will be deleted. Therefore, even when the total capacity of the map data to be transferred exceeds the storage area of the map data storage area, it is possible to prevent unnecessary map data from being deleted and a situation in which the memory becomes full.

A navigation system according to a seventh aspect of the present invention is the navigation system according to the first aspect, wherein the map data transfer means transfers the map data every time the moving body moves by a predetermined distance. I do.

According to the present invention, the map data transfer means transfers the map data from the first storage means to the second storage means at a timing when the moving body such as a vehicle travels and the position of the vehicle has moved by a predetermined distance. Perform a transfer. Therefore, it is possible to easily match the timing at which the predetermined area to be transferred substantially changes, and it is possible to smoothly perform the transfer process.

According to a eighth aspect of the present invention, in the navigation system according to the first aspect, the recording medium records block map data for each unit block obtained by dividing the entire map, and the first storage means Reading and writing to and from the second storage means are performed in units of the block map data.

According to the present invention, the map data recorded on the recording medium is obtained by dividing the entire map into unit blocks, collecting block map data for each unit block, and storing the first storage means and the second storage means. In the means, block map data is used as an access unit. Therefore, in the map data transfer process, the transfer block and the management of the map data can be easily performed because the transfer target unit block is selected and the transfer is repeated in order.

According to a ninth aspect of the present invention, in the navigation system according to the eighth aspect, the unit block is a rectangular area surrounded by sides parallel to the east-west direction and sides parallel to the north-south direction. And

According to the present invention, the map data recorded on the recording medium is obtained by dividing the entire map into a mesh to form a unit block, and the dividing lines are parallel to the east, west, and north and south, respectively. Therefore, the unit block in which the vehicle is traveling can be determined based on the latitude and longitude by detecting the own vehicle position, so that the corresponding transfer target area can be easily determined.

According to a tenth aspect of the present invention, in the navigation system according to the eighth aspect, the map data transfer means determines whether or not block map data to be transferred is already stored in the second storage means. And transferring only block map data not stored in the second storage means.

According to the present invention, when transferring the block map data, the map data transfer means determines whether or not the block map data is stored in the second storage means, and only when the block map data is not stored, the second storage means. Block map data is transferred to. Therefore, unnecessary transfer processing can be avoided, and the transfer processing can be executed quickly.

In the navigation system according to the eleventh aspect, in the navigation system according to the eighth aspect, the map data transfer unit may include an area including a plurality of peripheral unit blocks based on the unit block including a position of the own vehicle. Is a transfer target.

According to the present invention, the map data transfer means obtains a unit block including the position of the own vehicle, defines a range of the unit block around the position of the own vehicle based on the unit block, and determines a block within the range. Transfer map data.
Therefore, it is possible to transfer the block map data to the second storage unit in advance for a unit block that is likely to pass through a traveling vehicle.

[0030] According to a twelfth aspect of the present invention, in the navigation system according to the eleventh aspect, the map data transfer means is configured to increase a region including the plurality of unit blocks in a forward direction of the moving body. The transfer target is determined.

According to the present invention, the map data transfer means defines a relatively wide range forward in the traveling direction of the vehicle as the range of the unit block around the own vehicle position, and converts the block map data within this range. Forward. Therefore, the block map data on the front side in the traveling direction, which has a higher degree of use, can be transferred to the second storage means in advance in consideration of the possibility of passing within a short time.

According to a thirteenth aspect of the present invention, in the navigation system according to the eighth aspect, the map data transfer means includes an area composed of a plurality of unit blocks overlapping on an optimal route from the position of the vehicle to the destination. Is a transfer target.

According to the present invention, when the optimum route to the desired destination is set, the map data transfer means obtains a unit block overlapping the optimum route, and obtains a plurality of unit blocks from the own vehicle position along the destination. The range of the unit block is defined, and the block map data within this range is transferred. Therefore, the block map data can be transferred to the second storage unit in advance for the unit block that the traveling vehicle is scheduled to pass in advance.

According to a fourteenth aspect of the present invention, there is provided a navigation system for detecting a position of a vehicle, a communication means for obtaining map data from outside the moving body, and writing and reading of map data. A non-volatile storage unit, and map data obtaining unit which obtains map data from the outside by the communication unit at a predetermined timing with a predetermined area defined according to the vehicle position as a transfer target, and stores the map data in the second storage unit. And a navigation control means for controlling a navigation operation using the map data stored in the storage means.

According to the present invention, the navigation system includes communication means using radio waves or the like, obtains map data from the communication means, and thereafter obtains the second storage means in the same manner as in the first aspect. The navigation data is stored by storing the map data. Therefore, it is possible to simplify the configuration by substituting the device for reading the recording medium with the communication means, and to continue the navigation control even when the communication is temporarily interrupted.

[0036]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the overall configuration of the navigation system according to this embodiment. The navigation system shown in FIG.
2, a RAM 13, a DVD-ROM drive 14,
It includes a hard disk 15, a sensor unit 16, a GPS receiving unit 17, an interface 18, an input device 19, a display 20, a display control unit 21, a buffer memory 22, a sound processing circuit 23, and a speaker 24. It is configured.

In FIG. 1, a CPU 11 controls the operation of the entire navigation system. The CPU 11 is connected to each component of the navigation system, and
2 to read and execute the control program stored in
The data being processed is temporarily stored in the AM 13. CPU
Reference numeral 11 functions as a navigation control unit, a map data transfer unit, and a map data deletion unit of the present invention.

The DVD-ROM drive 14 functions as the first storage means of the present invention, and stores the map data in a DV-ROM drive.
The D-ROM 1 is mounted, and this map data is read out. DVD-ROM1 is 4.7G with one layer on one side
B, a recording medium having a large storage capacity of 8.7 GB with two layers on one side, pits corresponding to the recording data are formed on the disk, and the recording data is read out using the pickup of the DVD-ROM drive 14.

The DVD-ROM 1 stores map data including road shape data necessary for the navigation operation, and further stores various related data such as related facility data and name data in association with the road shape data. I have. In the present embodiment, the entire map is divided into blocks as mesh-shaped unit areas, and map data corresponding to each block is managed as block map data.
A plurality of block map data are recorded in the ROM 1.

FIG. 2 is a diagram for explaining the concept of a block which is a division unit of the map data of the DVD-ROM 1. As shown in FIG. 2, the map data of the DVD-ROM 1 is managed by dividing the entire area on the map into M blocks in the east-west direction and N blocks in the north-south direction, each of which is divided into mesh blocks. In FIG. 2, the block (i, j) is defined as the i-th block from the west and the j-th block from the north, and all blocks from the northwest end block (1, 1) to the southeast end block (M, N) are defined. , M × N blocks of the same shape are assembled to form the entire map data.

In FIG. 2, it is described that the whole area on the map is a rectangular area, and the blocks of each unit are also rectangular areas. In some cases, the shape of each block is not limited to the same shape. In the following description, for simplicity,
Each block is assumed to be a rectangular area of the same shape,
The present invention can be applied to a more complicated block shape.

FIG. 3 is a diagram showing an example of a data structure when the map data in block units shown in FIG. 2 is recorded on the DVD-ROM 1. In FIG. 3, each block map data includes road shape data of each block and related data associated therewith, and a specific name is given to each block to distinguish it. DVD-R
In OM1, block map data is recorded in order for each of the M × N blocks. The data order of the block map data shown in FIG. 3 is an example, and the data may be stored in a different data order. Further, the data may be stored in a different storage area for each data type of each block.

Returning to FIG. 1, the hard disk 15 is a nonvolatile storage device for reading and writing various data such as map data, and functions as the second storage means of the present invention. In the present embodiment, the hard disk 15
Can be used for many purposes, and can store various data such as music data, video data, and application programs. A part of the hard disk 15 is allocated as a map data storage area 15a, and is used as an area for transferring and storing the map data of the DVD-ROM 1. For example, about 1 to 2 Gbytes of the hard disk 15 may be allocated to the map data storage area 15a. It goes without saying that as the storage capacity of the hard disk 15 increases, more areas can be allocated. The details of the transfer of the map data to the hard disk 15 will be described later.

The sensor section 16 includes various sensors necessary for detecting the position of the vehicle. Specifically, it includes a vehicle speed sensor, a traveling distance sensor, a direction sensor, and the like for detecting a traveling state of the vehicle. The GPS receiving unit 17 receives a radio wave from a GPS (Global Positioning System) satellite and outputs positioning data. The sensor unit 16 and the GPS receiving unit 17 function as the vehicle position detecting means of the present invention in combination with the CPU 11.

The interface 18 performs an interface operation between the sensor unit 16 and the GPS receiving unit 17 and the CPU 11, and the CPU 11 performs the operation based on the sensor output from the sensor unit 16 and the positioning data from the GPS receiving unit 17. Vehicle position data is required. The vehicle position data is collated with the above-described map data by the CPU 11 and corrected using a map matching process or the like.

The input device 19 includes a key unit provided in the navigation system body or a remote controller having a key unit, and supplies a signal corresponding to the key input to the CPU 11 in order to perform a desired operation in the navigation operation.

The display 20 is a display means used for a navigation operation, and is composed of, for example, a CRT, a liquid crystal display element and the like. On the display 20, map data is displayed in various modes under the control of the display control unit 21, and the position of the own vehicle is displayed as a car mark so as to be superimposed on the map data. The display control unit 21 generates display data to be displayed on the display 20 and stores the display data in the buffer memory 2.
The display data is read out from the buffer memory 22 at an appropriate timing while being temporarily stored in the display 2.
Display output to 0.

The audio processing circuit 23 generates a predetermined audio signal under the control of the CPU 11. The audio signal amplified to an appropriate level in the audio processing circuit 23
4 is externally output. Such audio signals include
For example, there is a guidance voice for guiding a vehicle route.

In the present embodiment, the map data recorded on the DVD-ROM 1 is read out during the navigation operation, the display processing on the display 20 and the map matching processing are performed, and the map data necessary for the navigation operation is provided at an appropriate timing. Is transferred to the hard disk 15 and stored. The transfer of the map data is performed for each block in an area determined according to predetermined conditions based on the position of the vehicle. Then, the map data once stored in the hard disk 15 is retained as long as it is not deleted, and thereafter the map data can be read from the hard disk 15 instead of the DVD-ROM 1 to perform the navigation operation.

Next, a method of transferring map data to the hard disk 15 will be described with reference to FIGS. In the present embodiment, there are two ways to determine the block area to be transferred, and the two
There are two transfer methods. Hereinafter, each of the two transfer methods will be described.

First, a first transfer method according to the present embodiment will be described with reference to FIGS. FIG. 4 is a diagram showing a block area to be transferred in the first transfer method. Here, for simplicity, let us consider a range of 7 blocks in the horizontal direction and 7 blocks in the vertical direction, when viewed from the vehicle, for a total of 49 blocks.

In FIG. 4, when the vehicle is located at the host vehicle position P and the traveling direction is upward, the region R (the range indicated by oblique lines) corresponds to the block region to be transferred.
This region R includes a total of 16 blocks, and is set relatively wide forward in the traveling direction in consideration of the possibility of the vehicle passing. Note that the region R shown in FIG. 4 can be used regardless of the direction of travel of the vehicle in the north, south, east or west.

When transferring data to the hard disk 15,
It is necessary to detect the own vehicle position P as described above and determine a block including the own vehicle position P. In the present embodiment, as described above, since a mesh-shaped rectangular area is a block, it is possible to determine a block based on latitude and longitude. Further, the traveling direction of the vehicle can be determined, and the region R can be defined based on the block including the vehicle position P. If the corresponding block map data is not stored in the hard disk 15 for each of the 16 blocks included in the area R, the block map data is transferred to the hard disk 15 and sequentially stored in the map data storage area 15a. do it. Therefore, the number of blocks actually transferred to the hard disk 15 at the time of the transfer of the region R fluctuates according to the storage state of the hard disk 15.

The block area around the own vehicle position to be transferred can be set without being limited to the area R shown in FIG. The range may be wider or narrower than the region R, and the shape of the region may be freely set. It is desirable that the block area around the own vehicle position be appropriately set according to the frequency of the transfer processing, the size of each block, and the like. Further, the block area may not be fixed but may be variable according to the situation.

Next, FIG. 5 is a flowchart for explaining the processing by the first transfer method. In FIG. 5, when the processing is started after the navigation system is activated, in step S1, the host vehicle position P is detected. That is, based on the sensor output from the sensor unit 16 and the positioning data from the GPS receiving unit 17, the vehicle position data including the latitude and longitude is obtained.

Next, in step S2, step S
Based on the own vehicle position data obtained in step 1, the moving distance from the position where the previous transfer processing was executed is obtained, and it is determined whether or not the moving distance has exceeded a predetermined distance. That is, the execution timing of the transfer process can be variously set, but in the present embodiment, the transfer process is executed at a timing at which the vehicle has moved a predetermined distance. In addition, besides this, the transfer process is executed each time the vehicle moves from one block to another,
The transfer process may be executed at a timing when a predetermined time has elapsed.

If the result of determination in step S2 is that the travel distance of the vehicle has not reached the predetermined distance (step S2; N
O), the transfer process is not yet performed, and the process returns to step S1. On the other hand, when the moving distance of the vehicle has reached the predetermined distance (step S2; YES), the process proceeds to step S3. In step S3, the above-mentioned area R to be transferred is determined based on the vehicle position data. Specifically, as shown in FIG. 4, a region R may be defined based on the block including the host vehicle position P and the traveling direction of the vehicle, and 16 blocks included therein may be specified.

Next, in step S4, it is determined whether or not the block map data corresponding to each block of the area R determined in step S3 has been stored in the hard disk 15. Since block map data transferred in the past is sequentially stored in the map data storage area 15a of the hard disk 15, the presence or absence of predetermined block map data can be determined by referring to the block names in order. Alternatively, a management area may be provided in the hard disk 15 and a flag indicating whether or not each block map data is recorded may be written, and the flag may be referred to at the time of transfer.

If the result of determination in step S4 is that the target block map data has not yet been stored in the hard disk 15 (step S4; NO), the flow proceeds to step S5 to execute a transfer process. On the other hand, when the target block map data has been stored in the hard disk 15 (step S4; YES), the process proceeds to step S6 without executing the transfer process of step S5.

In the transfer process of step S5, the DVD-R
The block map data of each block recorded on the DVD-ROM 1 is read by the OM drive 14 and written into the map data storage area 15 a of the hard disk 15. FIG. 6 shows a state in which the DVD-ROM 1 is
FIG. 6 is a diagram for explaining the transfer of block map data to a. As shown in FIG. 6, after the block map data stored in the DVD-ROM 1 is read out by the DVD-ROM drive 14, it is temporarily stored in the transfer buffer 13a of the RAM 13. The transfer buffer 13a is a storage area on the RAM 13 provided for the transfer processing according to the present embodiment, and has a capacity capable of storing at least one block of block map data. Subsequently, the block map data held in the transfer buffer 13a is written to a predetermined recording position in the map data storage area 15a of the hard disk 15.

In FIG. 6, the CPU 11 is a DVD-R
Transfer between the OM driver 14 and the RAM 13 and RA
The transfer timing between the M13 and the hard disk 15 is controlled. Here, the RAM 13 may hold block map data of blocks around the vehicle for display processing by the display control unit 21 as described later. In this case, the DVD-ROM 1 must be read. Not
Block map data can be directly transferred from the RAM 13 to the hard disk 15.

Next, in step S6, it is determined whether or not the target block is still in the region R. As a result of the determination, when there is a target block remaining in the region R (step S6; YES), the process proceeds to step S4 to perform the transfer processing of steps S4 to S6 for the block. On the other hand, when the transfer processing has been completed for all 16 blocks in the area R (step S6; N
O), the process ends.

Next, FIGS. 7 to 9 are diagrams for explaining the relationship between the movement of the vehicle position and the storage state of the hard disk 15 in the first transfer method. In the following, a description will be given of the transition of the storage state of the block map data in the map data storage area 15a of the hard disk 15 when the own vehicle position during traveling changes in the order of FIG. 7, FIG. 8, and FIG.

FIG. 7A is a diagram showing a state of the peripheral blocks when the vehicle is located at the own vehicle position P1.
FIG. 7B is a diagram showing the layout of block map data stored in the map data storage area 15a of the hard disk 15 corresponding to FIG. In FIG. 7A, for convenience of explanation, a range of 7 blocks in the vertical direction and 5 blocks in the horizontal direction is considered, and blocks are described as blocks B1 to B35 in order from the upper left.

As shown in FIG. 7A, the own vehicle position P1 is included in the block B33. Therefore, based on the block B33, a block area similar to the area R in FIG. 4 is determined and defined as the area R1. Then, the transfer processing of steps S4 to S6 in FIG. 5 is executed for the 16 blocks included in the region R1. At this stage, the description will be made assuming that the block map data is not yet stored in the map data storage area 15a.

Then, as shown in FIG.
-The block map data of 16 blocks in the area R1 read from the ROM 1 is stored in the transfer buffer 1 of the RAM 13.
After that, the data is sequentially written to the map data storage area 15a. Writing is started from the head recording position A0 of the map data storage area 15a, and the block map data of the blocks B17 to B35 is stored in the range from the recording position A1 in the order shown in FIG. Note that the write order for the 16 blocks in the region R1 can be determined as appropriate.

FIG. 8A is a diagram showing a state of a peripheral block when the vehicle has moved from the own vehicle position P1 to the own vehicle position P2, and FIG. 8B corresponds to FIG. 8A. FIG. 7 is a diagram showing the arrangement of block map data stored in a map data storage area 15a. Here, the vehicle is located at the own vehicle position P2.
Is reached, the determination in step S2 of FIG.
Shall be

As shown in FIG. 8A, the own vehicle position P2 is included in the block B23. Therefore, the block area is determined based on the block B23 as described above, and is defined as the area R2. Then, the transfer processing of steps S4 to S6 in FIG. 5 is executed for the 16 blocks included in the region R2. At this time, the blocks B17, B18, B19, B22, B23, B
24 are determined to have already been transferred from the storage state of the hard disk 15, and the determination in step S4 in FIG. 5 is “YES”. Therefore, the remaining 10 blocks actually transferred are left.

As shown in FIG. 8B, a DVD-ROM
The block map data of 10 blocks in the area R2 read from the area 1 is stored in the map data storage area 15a in FIG.
The writing is started from the recording position A1 which is the head of the empty area in (b). Then, the block map data of the blocks B7 to 25 is newly stored in the range from the recording position A2 in the order shown in FIG.

FIG. 9A is a diagram showing the state of the peripheral blocks when the vehicle moves from the own vehicle position P2 to the own vehicle position P3, and FIG. 9B corresponds to FIG. 9A. FIG. 7 is a diagram showing the arrangement of block map data stored in a map data storage area 15a. As in the case of FIG. 8, when the vehicle reaches the own vehicle position P3, the determination in step S2 of FIG. 5 is “YES”.

As shown in FIG. 9A, the vehicle position P3 is included in the block B13. Therefore, the block area is determined based on the block B13 as described above, and is defined as the area R3 (a part of the area R2 is outside the range of FIG. 9A). Then, the transfer processing of steps S4 to S6 in FIG. 5 is executed for the 16 blocks included in the region R3. At this time, it is determined that six blocks B7, B8, B9, B12, B13, and B14 in the area R3 have already been transferred from the storage state of the hard disk 15, and the determination in step S4 in FIG.
S ". Therefore, the remaining seven blocks actually transferred (within the range of FIG. 9A).

As shown in FIG. 9B, a DVD-ROM
The block map data for seven blocks in the area R3 read from the area No. 1 is stored in the map data storage area 15a in FIG.
The writing is started from the recording position A2 which is the head of the empty area in. Then, block map data of blocks B2 to 15 are newly stored in the range from the recording position A3 in the order shown in FIG. 9B.

Thereafter, the position of the own vehicle moves and the step S
Each time the determination result of step 2 becomes “YES”, the same transfer processing is repeated, and new block data is stored one after another in the map data storage area 15a. If the storage capacity allocated to the map data storage area 15a is exceeded and new block map data cannot be written, the stored block map data may be deleted according to a predetermined condition. For example, the block map data with the oldest recording date on the hard disk 15 may be deleted,
What is necessary is just to delete the block map data of the block farthest from the own vehicle position. Thus, new block map data can be written to the map data storage area 15a.

According to the navigation system using the first transfer method according to the present embodiment, the position of the own vehicle is detected, the current block is determined, and a plurality of blocks around the own vehicle based on the detected position are transferred. In addition, the process of transferring the block map data from the DVD-ROM 1 to the hard disk 15 is performed, the storage state in the map data storage area 15a of the hard disk 15 is determined, and the unstored block map data is transferred. Therefore, it is possible to selectively store the block map data around the own vehicle, which is highly likely to be used, on the hard disk 15. When the block map data stored in the hard disk 15 is used, the navigation operation can be continued even when the DVD-ROM drive 14 is used for another purpose or when the disk is ejected. Since the blocks that the vehicle passes more frequently are more likely to be stored in the hard disk 15, the utility value of the map data stored in the hard disk 15 is further increased. Further, in general, even if the storage capacity of the map data storage area 15a is relatively small, the map data storage area 15a can cover the range of action of a specific vehicle.

Next, a second transfer method according to the present embodiment will be described with reference to FIGS. FIG. 10 is a diagram showing a block area to be transferred in the second transfer method. Here, for simplicity, 5
Consider a range of 75 blocks in total, 15 blocks in the vertical direction. In FIG. 10, it is assumed that the vehicle is located at the host vehicle position P and the traveling direction is upward.

In the second transfer method, a range overlapping with the optimum route set in the navigation system is set as a block area to be transferred. That is, in FIG. 10, it is assumed that the optimum route RT from the start position PS to the destination PE is determined and set based on a desired operation. At this time, 21 blocks from the block C1 including the start position PS to the block C21 including the destination PE through the middle blocks C2 to C20 along the optimal route RT are included in the optimal route R.
It overlaps on T.

Here, there are cases where the number of RT blocks on the optimum route becomes large, and the processing time required for the transfer needs to be limited. Therefore, the number of blocks to be transferred once to the hard disk 15 is limited to a predetermined number. I do. For example, in the case of FIG. 10, the number of target blocks is limited to 10 for one transfer process.
C becomes a transfer target. As shown in FIG. 10, the area RC includes a total of 10 blocks C1 to C10.
Then, similarly to the first method, the block map data corresponding to each block in the area RC is sequentially stored in the map data storage area 15a of the hard disk 15.

Next, FIG. 11 is a flowchart for explaining the processing by the second transfer method. In FIG. 11, after the navigation system is activated, in step S11, an optimal route RT to a predetermined destination is set according to a user operation or the like.

Next, in step S12, a block overlapping on the optimum route RT set in step S11 is determined, and in the order from the start position PS to the destination PE,
A list is created by listing the determined blocks. This list data is stored in a predetermined area of the RAM 13, for example. In the example of FIG. 10, the blocks C1 and C2
List data is created in the order of 1. The transfer target block may be a transfer target including not only a block overlapping the optimal route RT but also blocks around the optimal route RT.

Subsequently, in step S13, the position of the host vehicle is detected, and in step S14, it is determined whether or not the vehicle has moved a predetermined distance. The processing in steps S13 and S14 may be performed in the same manner as the processing in steps S1 and S2 in FIG. However, after setting the optimum route RT, the predetermined distance may be set to zero only when step S14 is executed first (the determination result of step S14 is “YES”), and the transfer processing of steps S15 to S19 may be performed immediately. .

If the decision result in the step S14 is "YES", in a step S15, the area RC to be transferred is determined by referring to the list data. FIG.
In the example, the area RC includes 10 blocks C1 to C10 from the block C1 including the own vehicle position.

Next, steps S16 to S18
Then, transfer processing of block map data corresponding to each block of the area RT determined in step S15 to the map data storage area 15a of the hard disk 15 is performed. The processes in steps S16 to S18 may be performed in the same manner as the processes in steps S4 to S6 in FIG.

If the decision result in the step S18 is "NO", the transfer process is ended once, and in a step S19, it is determined whether or not the vehicle has arrived at the destination PE (step S19). As a result, if the vehicle has not reached the destination PE (step S19; NO), the process proceeds to step S13 in preparation for the next and subsequent transfer processes. On the other hand, if the vehicle has reached the destination PE (step S19; YE
S), the process ends.

It is conceivable that the vehicle may deviate from the optimum route RT during traveling. Therefore, as a result of the determination in step S13, the block including the own vehicle position is determined to be the optimal route RT.
If it is determined that the vehicle is out of the range, the optimum route from the current vehicle position to the destination PE is newly obtained, the corresponding list data is created again, and the processing of steps S13 to S19 is repeated again. desirable.

According to the navigation system using the second transfer method according to the present embodiment, on the condition that the optimal route for navigation has been set, the set route R
The transfer processing of the block map data from the DVD-ROM 1 to the hard disk 15 is performed in the same manner as the above-described first transfer method, with a plurality of blocks overlapping on T as transfer targets. Therefore, in addition to the effect of the above-described first transfer method, map data along the optimal route RT, which has a very high possibility of the vehicle passing during the navigation operation, is transferred to the hard disk 15 in advance. Map data with high utility value
5 can be stored.

Next, display processing of a display screen based on map data will be described with reference to FIGS. FIG. 12 is a flowchart showing the display processing of the display screen based on the map data. FIG. 13 is a view for explaining the display range corresponding to the own vehicle position. FIGS. 14 and 15 are block diagrams of the display processing. FIG. 3 is a diagram illustrating data transfer. Here, a description will be given of a process performed when all block map data of the entire map (for example, all over Japan) is recorded on the DVD-ROM 1 and a part of the block map data is stored on the hard disk 15.

In FIG. 12, when the display process is started, in step S21, the position of the own vehicle is detected. Next, in step S22, the display range on the map to be displayed is determined based on the position of the vehicle.

Here, referring to FIG. 13, step S22
The display range determined by is described. In FIG. 13, it is assumed that blocks around the vehicle are arranged in the same manner as in FIGS. 7 to 9. A display range D1 when the vehicle is located at the host vehicle position P4 and a display range D2 when the vehicle is located at the host vehicle position P5 are indicated by dotted lines in FIG.
The display ranges D1 and D2 are set to rectangular areas slightly larger than the size of each block, and the roads and the like inside the display ranges D1 and D2 are drawn on the display 20. However, the shapes of the display ranges D1 and D2 in FIG. 13 are merely examples, and may actually be set larger or smaller.

In FIG. 13, since the display range D1 overlaps the blocks B23, B24, B28 and B29,
At the time of display processing, these four blocks of block map data are required. The display range D2 is the block B12,
Since these overlap with B13, B14, B17, B18, and B19, the block map data of these six blocks is required for the display processing. Thus, in step S22, the display range according to the movement of the vehicle may be determined, and the block to be displayed may be determined.

Next, in step S23, prior to transferring the necessary block map data to the RAM 13, whether or not new block map data is necessary corresponding to the block determined to be displayed in step S22 is determined. Judge. That is, the block map data necessary for the display processing is sent from the hard disk 15 or the DVD-ROM drive 14 to the display control unit 21 via the display transfer buffer 13b of the RAM 13 (see FIGS. 14 and 15). ), It is determined whether or not the necessary block map data is already stored in the display transfer buffer 13b.

If the result of determination in step S23 is that new block map data to be transferred to the display transfer buffer 13b is required (step S23; YES), the flow proceeds to step S24. On the other hand, when new block map data is unnecessary because it is already held in the display transfer buffer 13b (step S23; NO), step S2 is performed.
Return to 1.

Next, in step S24, step S2
It is determined whether the block map data determined to be necessary in step 3 has been stored in the map data storage area 15a of the hard disk 15 (step S24). This judgment is shown in FIG.
May be performed in the same manner as in step S4. As a result of the determination in step S24, if the data is already stored (step S24;
(YES), proceed to step S25, and if not stored (step S24; NO), proceed to step S26.

In step S25, the hard disk 15
From the block map data to the RAM 13. As shown in FIG. 14, under the control of the CPU 11, necessary block map data is read from the map data storage area 15a of the hard disk 15, and written to the display transfer buffer 13b of the RAM 13. Thereafter, the block map data is held in the display transfer buffer 13b until it is used for display processing by the display control unit 21 as described later.

On the other hand, in step S26, the DVD-RO
The block map data is transferred from the M drive 14 to the RAM 13. As shown in FIG. 15, under the control of the CPU 11, the DVD-ROM drive 14
Reads necessary block map data from M1 and stores it in RAM
13 to the display transfer buffer 13b. As described above, the block map data is held in the display transfer buffer 13b until it is used by the display control unit 21 for display processing.

[0096] Subsequent to step S25 or step S26, in step S27, the RAM 1 stores all the block map data determined to be necessary in step S23.
3 is determined. As a result of the determination, when the transfer of all necessary block map data is completed (step S27; YES), the process proceeds to step S28, and when the block map data to be transferred still remains (step S27; NO), Returning to step S24, the same processing is repeated.

In step S28, a display process is performed using the block map data held in the RAM 13.
That is, as shown in FIG. 14 and FIG.
The block map data necessary for the display processing is sequentially read from the display transfer buffer 13b, and sent to the display control unit 21 to perform the display processing. As a result, a display screen necessary for the navigation operation is displayed on the display 20.

By performing the display processing of the display screen according to the present embodiment, even when the DVD-ROM 1 storing the map data is not mounted on the DVD-ROM drive 14, the map data is already stored on the hard disk 15. If stored, display processing required for navigation can be performed. In addition, map data is frequently read from the hard disk 15 having a high access speed, so that the screen display becomes faster and scrolling and the like are performed quickly, so that a more comfortable navigation operation is performed.

In the above embodiment, the case where the DVD-ROM 1 is used as the recording medium on which the map data is recorded has been described, but the recording format on the recording medium is not limited to the DVD format. The recording medium is not limited to an optical disk or the like, and the present invention can be applied to a case where map data is downloaded via a network, for example.

The navigation system according to the above embodiment is not limited to being realized as an individual navigation device, but can be realized in combination with, for example, a personal computer having a hard disk. In this case, the functions of the above-described embodiments can be realized by operating software for executing the transfer processing of the present invention on a personal computer.

A DVD in which map data is recorded on a vehicle
-Instead of a recording medium such as a ROM, block map data may be transferred and acquired from a map server provided in a center that collectively manages map data outside the vehicle. In this case, a mobile phone is provided as a communication means on the vehicle side, and if block map data to be stored in the hard disk 15 is found on the vehicle side (the block map data stored on the hard disk 15 in the same manner as in the above embodiment) Is determined, the mobile phone accesses the center map server and downloads the block map data requested by the vehicle. By transferring the map data from the server by communication in this manner, a recording medium such as a DVD-ROM for recording read-only map data becomes unnecessary.

[0102]

As described above, according to the present invention,
Of the map data recorded on the recording medium, map data corresponding to a predetermined area defined according to the position of the vehicle is transferred from the first storage means to the second storage means. The storage means can be used for other purposes, and the map data of the area where the vehicle travels frequently can be intensively stored in the second storage means.
A highly convenient navigation system can be provided.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an overall configuration of a navigation system according to an embodiment.

FIG. 2 is a diagram illustrating the concept of a block that is a division unit of map data.

FIG. 3 is a diagram showing an example of a data structure when map data is recorded on a DVD-ROM.

FIG. 4 is a diagram illustrating a block area to be transferred in a first transfer method according to the embodiment;

FIG. 5 is a flowchart illustrating a process according to a first transfer method of the embodiment.

FIG. 6 is a diagram illustrating transfer of block map data from a DVD-ROM to a hard disk.

FIG. 7 is a diagram for explaining the relationship between the movement of the vehicle position and the storage state of the hard disk, and is a diagram for a vehicle position P1.

FIG. 8 is a diagram for explaining the relationship between the movement of the vehicle position and the storage state of the hard disk, and is a diagram in the case of the vehicle position P2.

FIG. 9 is a diagram for explaining the relationship between the movement of the vehicle position and the storage state of the hard disk, and is a diagram in the case of the vehicle position P3.

FIG. 10 is a diagram illustrating an area to be transferred in a second transfer method according to the embodiment;

FIG. 11 is a flowchart illustrating a process according to a second transfer method of the embodiment.

FIG. 12 is a flowchart showing display processing of a display screen based on map data.

FIG. 13 is a diagram illustrating a display range corresponding to the position of the host vehicle.

FIG. 14 is a diagram illustrating transfer of block map data stored in a hard disk in a display process.

FIG. 15 is a diagram illustrating transfer of block map data recorded on a DVD-ROM in a display process.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... DVD-ROM 11 ... CPU 12 ... ROM 13 ... RAM 13a ... Transfer buffer 13b ... Display transfer buffer 14 ... DVD-ROM drive 15 ... Hard disk 15a ... Map data storage area 16 ... Sensor part 17 ... GPS receiving part 18 ... Interface 19 Input device 20 Display 21 Display control unit 22 Buffer memory 23 Audio processing circuit 24 Speakers B1 to B35, C1 to C21 Blocks P, P1 to P5 Own vehicle position R1 to R3, RC area A0 to A4: Recording position RT: Optimal route PS: Start position PE: Destination D1, D2: Display range

Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) G09B 29/10 G06F 15/40 370C (72) Inventor Koichi Nagaki 61-1 Fujimi, Tsurugashima-shi, Saitama Pioneer Stock F-term in company research institute (reference) 2C032 HB05 HB25 HC05 HD03 2F029 AA02 AB07 AB13 AC02 AC09 AC14 AC16 AC18 AC20 5B075 ND07 PQ02 PQ69 UU13 5H180 AA01 BB13 CC12 FF04 FF05 FF22 FF25 FF32

Claims (14)

[Claims] 1. a vehicle position detecting means for detecting a vehicle position; a first storage means for reading the map data from a recording medium on which the map data is recorded; and a nonvolatile memory capable of writing and reading the map data. A second storage unit, reading out map data from the recording medium by the first storage unit at a predetermined timing with a predetermined area defined according to the vehicle position as a transfer target, transferring the map data to the second storage unit; Map data transfer means for storing, and navigation control means for controlling a navigation operation using map data recorded on the recording medium and map data stored in the second storage means. Navigation system. 2. The navigation system according to claim 1, wherein said second storage means is capable of writing and reading map data at a higher access speed than said first storage means. 3. The navigation system according to claim 2, wherein said second storage means is a hard disk drive. 4. When the map data necessary for the navigation operation is stored in the second storage unit, the navigation control unit uses the map data stored in the second storage unit, while using the map data for the navigation operation. 2. The navigation according to claim 1, wherein when necessary map data is readable from said recording medium and is not stored in said second storage means, map data recorded on said recording medium is used. system. 5. The navigation system according to claim 1, wherein a map data storage area for storing the transferred map data is set in the second storage unit. 6. When transferring the map data by the map data transfer means, if the storage capacity of the map data storage area is exceeded, a part of the map data in the map data storage area is deleted according to a predetermined condition. The navigation system according to claim 5, further comprising a map data deleting unit. 7. The navigation system according to claim 1, wherein the map data transfer means transfers the map data every time the moving body moves by a predetermined distance. 8. The recording medium stores block map data for each unit block obtained by dividing the entire map, and reading and writing to and from the first storage unit and the second storage unit are performed in units of the block map data. The navigation system according to claim 1, wherein the navigation is performed as: 9. The navigation system according to claim 8, wherein the unit block is a rectangular area surrounded by sides parallel to the east-west direction and sides parallel to the north-south direction. 10. The map data transfer means determines whether or not block map data to be transferred is already stored in the second storage means, and determines whether or not the block map data is not stored in the second storage means. The navigation system according to claim 8, wherein only the transfer is performed. 11. The navigation system according to claim 8, wherein the map data transfer unit transfers an area composed of a plurality of peripheral unit blocks based on the unit block including the position of the vehicle. . 12. The navigation system according to claim 11, wherein the map data transfer unit determines the transfer target such that an area including the plurality of unit blocks is widened in the forward direction of a moving object. 13. The navigation system according to claim 8, wherein the map data transfer unit transfers an area composed of a plurality of unit blocks overlapping on an optimum route from a position of the own vehicle to a destination. 14. A vehicle position detecting means for detecting the position of the vehicle, a communication means for obtaining map data from outside the moving body, a nonvolatile storage means capable of writing and reading map data, Map data obtaining means for obtaining map data from the outside at a predetermined timing by the communication means and storing the map data in the second storage means with a predetermined area defined in accordance with the vehicle position as a transfer target; and storing the map data in the storage means. And a navigation control means for controlling a navigation operation using the obtained map data.