JPS62293278A - Onboard navigator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an in-vehicle navigation device.

(Prior Art) Conventionally, in this type of in-vehicle navigation device,
A magnetic tape or a floppy disk was used as a recording medium, and map data was distributed and stored in several blocks.

For this reason, handling becomes complicated and troublesome, and a large-capacity CD-ROM is attracting attention.

(Problems to be Solved by the Invention) However, CDROMs have the disadvantage of being susceptible to scratches, dirt, etc. In addition, map data for navigation has changed from the method of recording the image as it is to the code method for the purpose of providing a zoom function, performing sensor correction using road information, and for the purpose of data compression. is becoming mainstream.

Therefore, it is important to consider how to compensate for the weaknesses of CDROM.

The present invention is intended to solve such conventional problems, and aims to provide an excellent in-vehicle navigation device that can minimize damage even when an error occurs. .

(Means for Solving the Problems) In order to achieve the above object, the present invention divides map data to be written on a CDROM disk into a plurality of blocks, and each block is divided into a directory part and a smaller small block. A directory portion configured from a group and having start information of a small block portion is repeatedly recorded a plurality of times, and error detection means for the directory portion;
If an error occurs, a means is provided to replace the information with another directory section having the same content.

(Function) Therefore, according to the present invention, when certain map data is read and the data cannot be read correctly due to an error due to scratches, dust, dirt, etc., if the part is a directory part, then , by replacing the data with other repeatedly recorded data in the same directory, it has the effect that an error does not lead to the disappearance of the entire block data.

(Embodiment) FIG. 1 is a schematic block diagram of an in-vehicle navigation device according to an embodiment of the present invention.

In FIG. 1, 1 is a direction/distance sensor, 2 is an operating means, 3 is a CD-ROM player, and 4 is a display means, which are connected to a control means 5.

Next, the operation of the above embodiment will be explained.

The control means 5 is activated by the operation means 2, and the CDRO
Map data is read from the M player 3 and a list of place names for map search is displayed on the display means 4.

By inputting or selecting a place name using the operation means 2,
The current position of the car is set and stored in the control means 5.

You can also enter your destination in the same way.

When the car moves, the direction and distance traveled are taken into the control means 5 from the direction/distance sensor 1, and the current position is calculated.

Then, the surrounding map of the updated position is displayed on the display means 4 together with the current position.

At this time, if there is no map data to be displayed in the control means 5, new map data is read out from the CDROM player 3.

If there is an error in the read data, it is determined whether the error is in the directory part, and if it is in the directory part, it is replaced with the directory part that is repeatedly written in the same block and processed.

The part of the data in which the error is indicated in the directory (
If it is a coordinate value of an intersection on a road, etc.), it is processed as is.

FIG. 2 is a flowchart of the map data reading operation, and shows the flow of the operation shown in FIG. 1.

FIG. 3 is a diagram showing an example of the structure of map data.

Figure 3(a) shows the block 1 director and block 1
It shows the arrangement of data from data to block n director and block n data.

FIG. 3(b) shows the arrangement from area C, which is the first recording data area, to area i, which is the nth recording data area.

(Effects of the Invention) As is clear from the embodiment described in Section 1, the present invention has the following advantages: Since the directory portion of map data is repeatedly and redundantly recorded on a CDROM disk, the influence of scratches, dirt, dust, etc. As a result, even if an error occurs, the portion of the directory that has a large chain effect can be read correctly, and the disturbance of the map due to the error can be kept to a small extent.

[Brief explanation of the drawing]

FIG. 1 is a schematic block diagram of an in-vehicle navigation device according to an embodiment of the present invention, FIG. 2 is a flowchart of a map data reading operation, and FIG. 3 is a diagram showing an example of the configuration of map data. 1... Direction/distance sensor, 2... Operating means, 3... CDROM player, 4... Display means, 5... Control means. Figure 1 Figure 2

Claims (1)

[Claims] Of the navigation map data part encoded as vector information, the directory part is repeatedly recorded on the CDROM disk multiple times, so that even if a read error occurs, the directory part can be read correctly, and the error is eliminated. An in-vehicle navigation device characterized by stopping the chain of events within a minimum range.