JPH0588477B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an in-vehicle map display device, and more particularly, to an in-vehicle map display device that displays maps with different densities in areas near a special vehicle and in other areas. It is.

[Prior Art] Conventionally, as one of the in-vehicle map display devices used to assist the driving of vehicles such as automobiles,
Some devices are configured to sequentially calculate the current location of the vehicle and display a map and a current location mark on the screen of the display means.

[Problems to be Solved by the Invention] However, in conventional map display devices of this type, the density of the displayed map was constant, so it is necessary to make it easier to understand the road situation near the current location of the vehicle. Therefore, if a map with a high density is displayed, detailed roads will be displayed in all areas on the displayed map, making the map very difficult to read.On the other hand, in order to make the whole map easier to see, we will display small roads such as national roads and prefectural roads with a low density. When displaying a map made up of major roads such as, there was a problem that the road conditions near the vehicle's current location could not be grasped.

SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide an in-vehicle map display device that displays a map that is dense near the vehicle's current location and less dense around it, and that is easy to see and use for vehicle occupants. It was created with the following purpose:

[Means for Solving the Problems] That is, the configuration of the present invention as a means for solving the above problems, as shown in FIG. 1, includes: a display means M1 for displaying a map; a map data storage medium M2 in which map data having level information set in advance is stored; and vehicle position detection means M3 for detecting the current location of the vehicle.
a display area specifying means M4 for specifying a region of the map to be displayed on the display means; a map data input means M5 for inputting map data of the specified area from the map data storage medium M2; a map display control means M6 for displaying a map on the display means based on the map data input from the map data input means M5; a first display map creation means M7 that creates a display map based on map data with coarse level information; and a display map of the vicinity of the current vehicle location detected by the vehicle position detection means M3, using the map data input means. a second display map creation means M8 that creates the input map based on map data with dense level information; and the first and second display map creation means M7, M
a map synthesis display control means M9 that synthesizes the display maps created in step 8 and displays on the display means a map that is dense for the vicinity of the vehicle's current location and coarse for the area surrounding the vehicle's current location; The gist of this paper is an in-vehicle map display device characterized by the following features:

Here, the display means M1 is for displaying a map and providing map information to a vehicle driver etc.,
It can be configured with CRT, liquid crystal dot display, LED, etc. Further, the storage means M2 stores the shape of the map displayed on the display means, the names of each part on the map, etc. as map data, and stores the shape of the map displayed on the display means, the names of each part on the map, etc. etc. can be used. In the map data stored in this storage means M2, a display level corresponding to the density of the map to be displayed is preset for each display object such as roads, rivers, railways, etc. constituting the map. Therefore, the density of the map displayed on the display means M1 can be changed using this display level. In other words, for example, if you set major roads such as national highways and prefectural roads as display objects at a coarse display level, and set municipal roads that are narrower than the main roads as display objects at a dense display level, you can create a low-density map. When displaying, display means M1
You can change the density of the displayed map, such as displaying a coarse map consisting of major roads, etc., and displaying a detailed map that includes major roads and municipal roads when displaying a high-density map. It is.

Next, the vehicle position detection means M3 detects the current location of the vehicle in which the map display device is mounted, and can be configured using sensors that respectively detect the distance traveled and the direction of travel of the vehicle. .
In addition, the display area specifying means M4 is the display area specifying means M1.
Specify the area to be displayed on the map data input method M
It is used to extract map data of the area corresponding to item 5 from the map data storage medium M2, and may be configured so that the display area can be specified by an operation by a vehicle occupant.

The map display control means M6 is for displaying a map on the display means M1 according to the map data extracted by the map data input means M5 and the current vehicle location detected by the vehicle position detection means M3. together with the map data input means M5,
It can be constructed by a control circuit including a microcomputer including a CPU, ROM, RAM, etc., and a drive device for driving the display means M1.

Here, among the components constituting the map display control means M6, the first display map creation means M7 includes:
It is configured to create a display map based on map data at a coarse display level of the map data input by the map data input means M5, and thereby a map of the area displayed on the display means M1. is created at low density.

Next, a second display map creation means M8 creates a display map in the vicinity of the current vehicle location detected by the vehicle position detection means M3, based on the map data with dense level information input by the map data input means M5. As a result, a detailed map consisting of, for example, city, town, and village roads near the vehicle's current location is created. Note that the map created by this second display map creation means M8 is of an area near the vehicle's current location, but specifically for this area, for example, the entire display map is divided into predetermined sections,
The mapping area may be a section to which the vehicle's current location belongs, or an area within a predetermined unit circle centered on the vehicle's current location.

and the first and second display map creation means M
The display maps created in steps 7 and M8 are combined by a map synthesis display control means M9, and the resulting map is displayed on the display means M1.

[Function] In the in-vehicle map display device of the present invention configured as described above, the display means M1 displays a fine, high-density map in the vicinity of the vehicle's current location, and a low-density, coarse map in the area surrounding the vehicle's current location. is displayed, allowing the user to accurately grasp the road conditions near the vehicle's current location, and displaying a map that is very easy to read as a whole.

[Example] An example of the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram showing the in-vehicle map display device of this embodiment. In the figure, reference numeral 2 includes the display designation means M4, which is an operation unit operated by a vehicle occupant when using the map display device, and 3 indicates the direction of travel of the vehicle, that is, the geomagnetic field relative to the vehicle on which the map display device is mounted. A direction sensor that detects the direction; 4 a distance sensor that detects the distance traveled by the vehicle;
5 is a map data storage device corresponding to the storage means map data storage medium M2 in which map data is stored in advance for each predetermined area; 6 is a CRT display which corresponds to the display means M1 and displays a map; 10
corresponds to the map data input means M5 and display control means M6, and includes a microcomputer 10-1 consisting of a CPU, ROM, RAM, I/O, etc. and a display controller 10-2, and is capable of displaying a map on the CRT display 6. This is a control device that executes arithmetic processing and display control for display.

Here, the operation unit 2 includes a designation key for designating the area to be displayed, a cursor key for inputting the current location of the vehicle on the currently displayed map, and the like.

The orientation sensor 3 includes a ring-shaped permalloy core, an excitation coil, and two coils perpendicular to each other, and generates an orientation signal to detect the traveling direction of the vehicle relative to the earth's magnetic field based on the output voltages of these two coils. is output to the control device 10.

Next, the distance sensor 4 indirectly detects the rotation of the speedometer cable and the output shaft of the transmission.
It is detected as an electrical signal by a reed switch, a magnetic sensing element, a photoelectric conversion element, etc., and outputs a distance signal to the control device 10, which is used to calculate the distance traveled by the vehicle. Furthermore, this distance sensor 4
and the direction sensor 3 is the vehicle position detection means M
Corresponds to 3.

On the other hand, the microcomputer 10 of the control device 10
There are two video RAM areas in the RAM of -1 that directly represent the display contents of the CRT display 6.
VRama and VRAMb are provided, and the display controller 10-2 synthesizes the display contents of these two VRAM areas and displays it on the CRT display 6.

Next, the map data storage device 5 is constituted by an optical disk storage device, and map data for each area is stored in the optical disk. The stored map data is read out using laser light, and is sent to the control device 10 for processing.

The data on this optical disk includes, for example, as shown in FIG. 3, a header 12 that is an identification symbol of regional map data, a route information string 20 regarding various routes on the map of the region, and information on each part on the map. It is composed of a name information string 30 regarding each name, etc.

Here, the route information string 20 includes route information strings 21-1, 21-2, etc. for each route (linear display object) such as roads, rivers, railways, etc. on the map, and their pointers 2.
2-1, 22-2, ..., and the route information columns 21-1, 21-2, ... for each route display this route in accordance with the route number representing the route and the density of the map, respectively. It consists of a route display level indicating whether or not to do so, a point information group of each point forming the route, and route end information. Further, the point information for each point forming the route is composed of a point number representing the point and map coordinates (X, Y) representing the position.

Next, the article information column 30 includes the intersection information column 31-
1. Consisting of root name information strings 31-2,... and pointers 32-1, 32-2,... which correspond one-to-one to these name information strings 31-1, 31-2,... The intersection information column 31-1 is composed of a plurality of intersection name information in which point numbers, display levels, and intersection names are set for each intersection, and the route name information column 31-2 is composed of a plurality of intersection name information in which point numbers, display levels, and intersection names are set for each intersection. It is composed of multiple pieces of route name information in which numbers, name levels, and route names are set. As with the point level, this name display level is a level that indicates whether or not to display the name, corresponding to the density of the displayed map.

Here, the above display level and name display level correspond to the above-mentioned level information that is set corresponding to the density of the displayed map, and in this example, main roads such as toll roads, expressways, national roads, prefectural roads, etc. as well as,
For the main intersections of each road, level information of rank "0" is set so that the display map can be displayed in both low density and high density, and for other general local roads and main intersections on that road, , level information of rank "1" is set to be displayed only when displaying a high-density map.

In the in-vehicle map display device of this embodiment configured as described above, the map of the area specified by the vehicle occupant is created in high density near the vehicle's current location and in low density around it, and is displayed on the CRT display 6. This map display control process will be explained below with reference to the flowchart shown in FIG.

When the process starts, first execute step 101,
It is determined whether or not a map to be displayed on the CRT display 6 has been designated by operating the operation unit 2 by the vehicle occupant.

Once the map is specified, the process moves to step 102.
The map data of the corresponding area in the map data storage device 5 is input. This process corresponds to the map data input means M5, and can be easily executed by sequentially searching the header, which is an identification symbol of each map data.

In the following step 103, the input map data is grouped according to the display level. Then, in the next step 104, the map data of the grouped display level "0" is input into the VRama area,
In the next step 105, map data of display level "1" is input into the VRAMb area.

In this way, the map data is divided into display levels "0" and "1", and the display levels are divided into VRMa areas and
Once input into the VRAMb area, the subsequent step 106 is executed to synthesize the map data grouped above,
Display the map on CRT display 6.

Next, in step 107, it is determined whether or not the vehicle's current location has been input on the map by the vehicle occupant operating the cursor keys on the operating section 2. When the current location of the vehicle is input, the brightness at that point is increased in step 108, and the current location of the vehicle is displayed on the map as is.

Once the current vehicle location is entered, proceed to step 109.
, create a mask pattern with radius R centered on the input current location, and proceed to the following steps.
Move to 110. This mask pattern is used so that the displayed map has high density in the area of radius R centered on the current location of the vehicle, and low density in other areas.

In step 110, the map data input into the VRAMb area is masked using the mask pattern created above, and the map data is input as is in the area with a radius R centered on the vehicle's current location, and the map data is input as is in the other areas. Now let's create map data with no display objects.

Then, in the following step 111, the above masked
The map data in the VRAMb area and the map data input in the VRama area are combined to change the displayed map on the CRT display 6.

Next, in step 112, the current location of the vehicle, which changes as the vehicle travels, is calculated based on the detection signals from the azimuth sensor 3 and distance sensor 4, and the process proceeds to step 113.

In step 113, it is determined whether the distance between the vehicle's current location determined above and the vehicle's current location currently displayed on the CRT display 6 is a predetermined distance or more, that is, whether the vehicle has moved by a predetermined distance or more. . The processes of steps 112 and 113 described above are repeated until the vehicle has moved beyond a predetermined distance, and then, when it is determined in step 113 that the vehicle has moved beyond a predetermined distance, step 108 is executed.
Then, the process of steps 108 to 113 is executed again.

Figure 5 shows that the CRT display 6 is displayed as a result of the above processing.
It is an image diagram showing changes in the map displayed above. First, as shown in Fig. 5A, processing is started,
The map displayed for the first time on the CRT display 6 through the process of step 106 is a composite of map data corresponding to each display level "0" and "1" in all areas as shown in Figure 6 A and B, respectively. This results in a dense map. After that, the vehicle's current location is input, and when that location _P1 is displayed, a mask pattern with a radius R centered on the vehicle's current location _P1 as shown in FIG. 7 is created, and in step 111, as shown in FIG. In addition, a map with high density in the area α of radius R centered on the vehicle's current location and low density in other areas will be displayed. When the vehicle moves to point _P2 , which is a predetermined distance or more away from point P1, the displayed map changes to the _fifth point.
As shown in Figure C, the map is changed to a map in which the area β of radius R centered on point _P2 has a high density.

As explained above, in the in-vehicle map display device of this embodiment, on the CRT display 6,
A map with high density within a unit circle centered on the vehicle's current location and low density in other areas will be displayed. Therefore, surrounding road conditions can be grasped in detail near the vehicle's current location, and when the vehicle is located near the destination, it is possible to provide accurate route guidance to the destination. In addition, in areas other than the vehicle's current location, a rough map consisting only of major roads is displayed, making the map easy to read, and when the destination is far away, it is easy to determine the route to use to get to the destination. can do. Furthermore, even if the route the vehicle is traveling in is congested or the road is closed due to construction, the map is densely packed near the vehicle's current location.
Other driving routes can be easily found.

In the above embodiment, the area for high-density map display is an area within a predetermined radius centered on the vehicle's current location, but the entire display area may be divided into four blocks as shown in FIG. The area where the vehicle is located may be divided into two areas, and the block where the vehicle is located may be used as a high-density display area. In this case, the displayed map will be as shown in FIG. 8B, for example.

[Effects of the Invention] As described in detail above, in the in-vehicle map display device of the present invention, the map displayed on the display means M1 is dense in the vicinity of the vehicle's current location, and is coarse in the area surrounding the vehicle's current location. Therefore, the road situation can be grasped in detail near the vehicle's current location, and the map as a whole becomes very easy to read, making the map display device highly useful for vehicle occupants.

[Brief explanation of drawings]

Figure 1 is a block diagram showing the configuration of the present invention, Figure 2 is a block diagram showing the configuration of the present invention.
7 to 7 show one embodiment of the present invention, and a second embodiment of the present invention is shown in FIG.
3 is a block diagram showing the configuration of this embodiment, FIG. 3 is a configuration diagram of map data, FIG. 4 is a flowchart showing the map display control process executed by the control circuit 10, and FIG. 5 is a flowchart showing the process. An explanatory diagram showing changes in the map displayed on the CRT display 6,
Figure 6 A is an explanatory diagram showing a map created using map data at display level "0" (coarse), and Figure 6 B is an explanatory diagram showing a map created using map data at display level "1" (dense). FIG. 7 is an explanatory diagram showing a mask pattern created centering on the current vehicle location _P1 , and FIG. 8 is an explanatory diagram showing another example of map display. 2... Operation unit, 3... Orientation sensor, 4... Distance sensor, 5... Map data storage device, 6... CRT display, 10... Control device.

Claims (1)

[Claims] 1. A display means for displaying a map, a map data storage medium in which map data having level information set corresponding to the density of the map is stored in advance, and a vehicle position for detecting the current location of the vehicle. a detecting means; a display area specifying means for specifying a region of the map to be displayed on the display means; a map data input means for inputting map data of the specified area from the map data storage medium; and the input map. A map display control means for displaying a map on the display means based on the data; and a map display control means for displaying a map on the display means based on the map data input means. a first display map creation means for creating a display map based on rough map data; and a first display map creation means for creating a display map based on rough map data; The display map created by the first and second display map creation means is combined with the second display map creation means that creates the map data based on the dense map data, and the display map created by the first and second display map creation means is densely mapped for the vicinity of the current vehicle location. An in-vehicle map display device comprising: map synthesis display control means for causing the display means to display a rough map for the area surrounding the vehicle's current location.