JPH09237041A - On-vehicle map display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a map display device which promptly switching the scale of the road map displayed on the display screen in compliance with an external instruction. SOLUTION: A CPU 12 is operated to read two kinds of map data stored in a CD-ROM different in scale when instructed externally and, based on each of map data, generates each of the image data for displaying road maps on a display device 4 and stores them into VRAMs 30a, 30b. The image data stored in these VRAMs are transformed into video signals by video controllers 32a, 32b, which causes a display switching SW 34 to select one of the transformed video signals and output the selected signal to a display device 4. As the result, the scale of the road map displayed on the display device 4 can be instantaneously switched over. In addition, it is possible to change the scale of the road map for each of VRAMs 30a, 30b by inputting an instruction of change in the state where the road map is displayed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicular map display device for displaying a road map including the present vehicle location on a display device.

[0002]

2. Description of the Related Art Conventionally, in this type of vehicle map display device, in order to be able to change the scale of a road map displayed on the display device, map data of different scales are previously stored.
When the road map is stored in a storage medium such as a CD-ROM and is displayed on the display device, the map data at a reduced scale specified by the user is read out from this storage medium and the read map data is used for display. Image data for the vehicle is generated and the road map is displayed on the display device.

[0003]

However, in the conventional vehicle map display device, according to the instruction from the user, the road map displayed on the display device is displayed as a detailed map having a smaller scale than the current road map or the current road map. When switching to a wide area map that has a larger scale than the road map, the new map data corresponding to the commanded scale must be read from the storage medium, and the image data for display must be rewritten based on the read map data. However, there is a problem that it takes time to change the scale of the displayed map.

Therefore, in the conventional vehicle map display device,
For example, in the state where the vehicle is traveling while displaying the detailed map near the current location on the display device and checking the traveling road,
In order to confirm the route from the current location to the destination, temporarily display a wide area map on the display device, and after confirming the route, respond to the user's request to return the displayed detailed map to the original detailed map. I couldn't. In addition, in order to switch such a map, if the user inputs a scale change command and the road map is once switched to the wide area map, then the scale of the map is changed back to the original detailed map. Even if a change command is input, it takes time for the displayed map to return to the detailed map. During that time, it is not possible to check the road near the current location on the display screen, and there is also the problem of poor usability.

On the other hand, as disclosed in Japanese Patent Publication No. 5-2814, for example, as a map display device for a ship that displays a nautical chart, a detailed map near the target position is displayed on the entire display screen, and the display is performed. Detailed area on the map,
A map display device is known which displays a wide area map including the position of the ship and the target position. That is, in this device, two types of maps with different scales are simultaneously displayed on the display screen of the display device.

Therefore, if such a technology for a ship is applied to a map display device for a vehicle, a detailed map near the present location is displayed on the entire display screen, and a partial area on the detailed map from the present location to the destination is displayed. Wide area map can be displayed. By doing so, it is possible to confirm the route to the destination while confirming the road near the current location, and the usability of the vehicle map display device can be improved.

However, in this case, since the wide area map is displayed in a partial area on the detailed map, the display of the wide area map obscures the road near the present location that the user wants to check, or the wide area. Since the map is displayed in an extremely narrow area on the display screen, there is a problem that the route to the destination cannot be confirmed on the display screen.

The present invention has been made in view of these problems, and in a vehicle map display device capable of displaying road maps of different scales, two types of different scales are displayed on a display screen as disclosed in the above publication. It is possible to improve the usability of the vehicle map display device by enabling the scale of the road map to be displayed on the display screen instead of displaying the map of To aim.

[0009]

According to another aspect of the present invention, there is provided a map display device for a vehicle, wherein the image data generating means includes:
The map data of a predetermined area including the vehicle current location detected by the current location detection means at the scale instructed by the scale instruction means is read, and based on the read map data,
Image data for displaying a road map including a mark indicating the current vehicle position on the display means is generated and stored in the image data storage means.

Further, in the present invention, a plurality of the image data generating means and a plurality of image data storing means for storing the image data generated by the image data generating means are respectively provided, and the plurality of display control means are provided. The image data stored in any one of the image data storage means is selected, and an image (that is, a road map including the current vehicle position) is displayed on the display means based on the selected image data. Then, when the switching command means inputs a switching command for the road map to be displayed on the display means, the display control means changes the image data used for display to the image data stored in another storage means.

On the other hand, the plurality of image data generating means are
Respectively, from the map data storage means, the map data of the scale commanded by the scale command means is read out and the image data is generated. In this way, the map data necessary for each image data generation means to generate the image data is stored. The scale is stored in the scale storage means. Then, when the scale is instructed from the scale instructing means, the scale changing means is a scale for the image data generating means for generating the image data being displayed on the display means among the scales stored in the scale storing means. To the commanded scale.

Therefore, according to the vehicle map display device of the present invention, the image data for displaying the road map on the display means are independently generated by the plurality of image data generation means, and the generated images are generated. The data will be individually stored in the plurality of image data storage means, and if a switching command of the road map is inputted from the outside through the switching command means, the operation of the display control means causes the image data for display to be displayed. The road map displayed on the display means can be quickly switched without being regenerated. Therefore, according to the present invention, as described above, a user who wants to temporarily display a wide area map with the detailed map displayed on the display device and then quickly return the displayed map to the detailed map. It is possible to provide a vehicle-use map display device that is easy to use and can sufficiently meet the above-mentioned requirements.

Further, the scale of the road map that can be changed by the switching command from the switching command means is determined by the scale stored in the scale storage means for each image data generating means.
In the present invention, if the scale is instructed from the scale instructing means, the image data generating means for generating the image data of the road map displayed on the display means at that time out of the scales stored in the scale storing means. Since the scale is changed to the commanded scale, the scale of the road map that can be changed by the switching command can be changed to an arbitrary scale for each road map. Therefore, if the scales of the respective image data generating means stored in the scale storing means are set to the desired scales, respectively, the display means can always display the road map at the desired scales. Can improve the usability of the device.

Further, in the vehicle map display device according to the second aspect, the scale command means can input a scale switching command for switching the scale of the road map displayed on the display means to the wide area side or the detailed side. Is composed of. Then, in the scale changing means, when a scale switching command is input from the scale commanding means, first, the scale coincidence determining means generates the image data which is being displayed on the display means in accordance with the scale switching command. When the scale for the generating means is changed, it is determined whether or not the scale after the change matches the scale of the map data used by other image data generating means to generate the image data, and this scale matching determining means When it is determined that the scale after the change does not match the scale for the other image data generating means, the scale changing executing means changes the scale stored in the scale storing means in accordance with the scale switching command, and conversely, the scale matching determination is made. If the means determines that the scale after the change matches the scale for the other image data generating means, the switching command generation means outputs a map switching command to the display control means to control the display. The image data that stage is selected, to change to the image data generated by the other image data generating means is determined that the scale matches.

That is, if the scale for the road map being displayed is changed as it is in accordance with the scale switching command from the scale changing means, the same scale may be set for a plurality of image data generating means. Therefore, in the present invention, in order to prevent such a situation, when a scale switching command is input from the scale commanding unit, if the scale is directly changed according to the switching command, the same scale is set for the two image data generating units. Check whether or not to allow the scale change only when the scales do not overlap, and prohibit the scale change when it is determined that the scales overlap. Since the scale of the image is not changed and the user feels uncomfortable, the image data used for displaying the road map can be changed to the scale corresponding to the scale change command. Than it has been so switched on.

Therefore, according to the present invention, it is possible to prevent the plurality of image data generating means from reading the map data of the same scale and generating the image data, and to display when the road map switching command is input. Since the scale of the road map displayed on the means is always changed, the road map switching function can be surely exhibited.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 1 is a block diagram showing the overall configuration of an automobile navigation apparatus of an embodiment to which the present invention is applied.

As shown in FIG. 1 (a), the navigation device of this embodiment has a GPS (Global Positioning System).
m) is equipped with a GPS antenna 2a for receiving radio waves transmitted from an artificial satellite, the received signal is frequency-converted, demodulated, and the latitude and longitude representing the position of the receiving point (in other words, the current position of the vehicle), A GPS as a current position detecting means for calculating position data including altitude and the like, and calculating speed data indicating a moving speed (that is, vehicle speed) of a receiving point and azimuth data indicating a moving direction (that is, a traveling direction of a vehicle) of the receiving point A receiving unit 2, a display device 4 as a display means including a liquid crystal display for displaying a road map, a travel route, etc., a CRT, and a CD storing map data for displaying a road map on the display device 4. A ROM-removably mountable CD-ROM drive 6 for reading map data from the mounted CD-ROM, and a road map displayed on the display device 4 A keyboard (not shown) as a scale command means and a switch command means for the user to input various commands such as a switch command and a command to switch the scale of the road map by an external operation is provided from the keyboard. A remote control transmitter 8 which converts various commands into transmission signals and transmits the signals, and various data from the GPS receiving unit 2, the CD-ROM drive 6, the remote control transmitter 8 and the like,
The control device 10 is configured to display a road map, a traveling route, and the like on the display device 4 based on the data.

At a predetermined position below the display screen of the display device 4, in addition to the remote control transmitter 8, an operation switch 4a as a scale commanding means for inputting a command to change the scale of the road map, and An operation switch 4b is provided as a switching command means for inputting a road map switching command displayed on the display device 4.

Next, as shown in FIG. 1B, the control device 10 is composed of a CPU 12, a ROM 14, a RAM 16, and a microcomputer centering on a bus 18 for connecting these parts, and the ROM 14 is preliminarily provided. Various calculation processes for displaying a road map including the current vehicle position on the display device 4 are executed according to a control program stored therein. Further, the bus 18 has a GPS receiving unit 2 and a CD.
-Reception units 20 for receiving transmission signals (remote control signals) from the ROM drive 6 and the remote control transmitter 8 are respectively connected to transfer data from these units to the CPU 12 and to transfer control signals from the CPU 12 to the CD- Input / output interface (I / I) for outputting to the ROM drive 6
O) 22 and video RAMs (VRAMs) 30a and 30b for storing two types of image data (for example, bitmap data) generated by the CPU 12 in the processing described later and for displaying the road map on the display device 4. It is connected.

Then, in each VRAM 30a, 30b,
A video controller 3 which reads out image data from each of the VRAMs 30a and 30b and converts it into a video signal (for example, an RGB signal) for displaying a road map on the display device 4.
2a and 32b are connected to the respective video controllers 32a and 32b, and C is connected to these video controllers 32a and 32b via the I / O 22.
A display changeover switch (display changeover SW) 34 for selecting either one of the video signals output from the video controllers 32a and 32b according to the display changeover signal transmitted from the PU 12 and outputting it to the display device 4 is provided. It is connected.

The above VRAMs 30a and 30b are
Each is for storing one screen of image data for displaying a road map on the display device 4, and in this embodiment, the VRAM 30a is for displaying detailed maps and the VRAM 30b is for displaying detailed maps.
Is used for wide area map display. Then, in the present embodiment, each of these VRAMs 30a and 30b corresponds to the image data storage means of the present invention, and the video controller 32.
The a and 32b and the display switching SW correspond to the display control means of the present invention.

In addition, a part of the RAM 16 is designed such that the stored data can be always held by a built-in battery, and the backup area thereof has a scale of the road map when the detailed map is displayed (in the detailed mode), The scale of the road map used when the wide area map is displayed (in the wide area mode) is stored. That is, the RAM 16 corresponds to the scale storage means of the present invention.

On the other hand, the CD-ROM as a map data storage means mounted in the CD-ROM drive 6 has a structure shown in FIG.
As shown in (a), the map data of all areas to be displayed, such as the whole country, Kanto area, Kansai area, ... Represents the distance on the map per unit length, for example, corresponding to eight scale lengths. (In other words, corresponding to the eight different scales of the road map) are stored respectively. As shown in FIG. 2B, the map data for each reduced scale is composed of a large number of unit map data divided corresponding to the size of one screen of the display device 4. Therefore, when displaying the road map on the display device 4, the control device 10 has the largest scale length of 200 km (in other words, the smallest scale ratio) and the smallest scale length of 100 m from the wide area map (in other words For example, the scale of the displayed map can be switched in 8 steps, up to the largest scale).

Next, the map display processing executed by the CPU 12 to display the road map on the display device 4 in the navigation apparatus of this embodiment will be described with reference to the flowchart shown in FIG. As shown in FIG. 3, when this process is started, first, in S100 (S: step), a detailed mode for displaying a detailed map is initially set as a display mode for displaying a road map, and The scale of the detailed map displayed in the detailed mode and the scale of the wide area map displayed in the wide area mode are initially set.

In this initial setting process, when the navigation device is just shipped and the scale of each display mode in detail and wide area is not stored in the backup area of the RAM 16, the scale of each display mode is set. If a preset initial value is set and the scale of each display mode used last time is stored in the backup area of the RAM 16, that scale is initialized as the scale to be used this time.

Next, in S110, the current position of the vehicle determined by the GPS receiving unit 2 (specifically, coordinate data)
Read. Then, in the subsequent S120, the CD-ROM
From the map data corresponding to the scale (scale length) in the detailed mode among the map data for each scale (scale length) stored in, as shown in Fig. 2 (b), unit map data including the current location P0 and unit map data P1 around it
The unit map data P0 to P8 for a total of 9 screens including P0 to P8 are stored in the RAM 16 once as the map data for the detailed map display, and the stored map is stored. Image data (bitmap data) for displaying a detailed map on the display device 4 is created based on the map data of one screen area centering on the current vehicle position in the data.

As described above, when the image data for displaying the detailed map is created in S120, the data content of the VRAM 30a for displaying the detailed map is updated based on the created image data in the subsequent S130. To do. Note that S
In 120, the unit map data for 9 screens centering on the current vehicle location is already stored in the RAM 1 as map data for display.
If it is stored in No. 6, the image data is created based on the map data without reading the unit map data. When the current position is no longer included in the map data P0 stored in the RAM 16 as the vehicle travels, the shortage unit map data is read from the CD-ROM and stored in the RAM 16 to eliminate unnecessary units. The map data is deleted from the RAM 16. Further, the image data created in S120 is not simply the image data for displaying the road map on the display device 4, but as shown in FIG.
This is image data in which additional information such as the vehicle mark G indicating the current vehicle position and the scale length is added on the road map (which is the center position in this embodiment).

Next, in S140, nine screens centered on the current location are selected from the map data corresponding to the scale (scale length) in the wide area mode among the map data for each scale stored in the CD-ROM. The minute unit map data P0 to P8 are read, and the image data for displaying the wide area map on the display device 4 is created by the same procedure as in S120. Then, when the image data for wide area map display is created in S140, the data content of the VRAM 30b for wide area map display is updated based on the created image data in subsequent S150.

Incidentally, the above S120, S130 and S14
The processes of 0 and S150 respectively correspond to the image data generating means of the present invention. Next, in S160, it is determined whether or not a scale map change command has been input by operating the operation switch 4a or the remote control transmitter 8 provided on the display device 4, and the scale change command has been input. If so, S2
After shifting to 00 and executing a display map scale changing process which will be described later, shift to S110.

On the other hand, if it is determined in S160 that the road map scale change command has not been input, this time S1 is executed.
In step 70, it is determined whether a road map switching command (that is, a display mode switching command) has been input by operating the operation switch 4b provided on the display device 4 or the remote control transmitter 8. Then, if the display mode switching command is not input, the process directly proceeds to S110, and if the display mode switching command is input, in S180,
After switching the currently set display mode to the other display mode, the process proceeds to S110.

That is, in S180, if the detailed mode for displaying the detailed map is currently set as the display mode, the display mode is switched to the wide area mode for displaying the wide area map, and conversely, the current display mode is set. If the wide area mode for displaying the wide area map is set, the display mode is switched to the detailed mode for displaying the detailed map. Further, in S180, not only the setting of the display mode is switched, but also the display switching signal is transmitted to the display switching SW 34, so that the display switching SW3 is switched according to the display mode.
4 selects the video signal on the video controller 32a side or the video signal on the video controller 32b side and outputs it to the display device 4.

As a result, according to the navigation device of this embodiment, for example, the VRAM 30a for displaying the detailed map is displayed.
In FIG. 5, image data corresponding to a detailed map with a scale length of 200 m as shown in FIG. 5A is stored, and when the display mode is the detailed mode and the detailed map is displayed on the display device 4, Operation switch 4 provided on the display device 4
b or the remote control transmitter 8 is operated to input a display mode switching command, the display mode is switched to the wide area mode, and the display screen of the display device 4 is changed to the wide area map as shown in FIG. The wide area map corresponding to the image data stored in the display VRAM 30b is instantly switched. Note that FIG. 5B shows a VRA for wide area map display.
A display screen when image data corresponding to a wide area map having a scale length of 2 km is stored in M30b is shown.

Next, the display map scale changing process executed in S200 will be described with reference to the flowchart shown in FIG. This process is a process corresponding to the scale changing means of the present invention. When this process is started, the change command input this time in S210 is a command for changing the scale of the road map currently being displayed to a wide scale. Or not. Then, if the change command input this time is a scale change command to the wide area side, the process proceeds to S220, and it is determined whether or not the current display mode is the wide area mode. Even if the scale of the road map currently being displayed is changed to the wide area side, it does not match the scale of the detailed mode. Therefore, the process directly proceeds to S240, and the scale of the current display mode (in this case, wide area mode) is set to the wide area side. And the process is ended once.

On the other hand, when it is determined in S220 that the current display mode is not the wide area mode (that is, the detailed mode), the processing proceeds to S230 and the scale of the road map currently displayed is set to the wide area side. If it is changed as it is, it is determined whether the scale after the change matches the wide area mode. If the scale after the change does not match the wide area mode, the process proceeds to S240, the scale of the current display mode (in this case, the detailed mode) is updated to the wide area side, and the process is temporarily terminated. On the contrary, if the scale after the change coincides with the wide area mode, the process proceeds to S250 and the above-described S1 is performed.
The display mode is switched from the current display mode (detailed mode in this case) to another display mode (wide area mode in this case) by the same procedure as the processing of 80, and the processing is temporarily terminated.

On the other hand, in S210, it is determined that the change command input this time is not a command to change the scale of the road map currently being displayed to the scale of the wide area (that is, the scale change command to the detail side). In this case, the process proceeds to S260, it is determined whether the current display mode is the detailed mode,
In the detailed mode, even if the scale of the currently displayed road map is changed to the detailed side, it does not match the scale of the wide area mode. Therefore, the process directly proceeds to S280, and the current display mode (in this case, the detailed mode). ) Update the scale to the detail side,
The process is once ended.

If it is determined in S260 that the current display mode is not the detailed mode (that is, the wide area mode), the process proceeds to S270 and the scale of the road map currently displayed is set to the detailed side. If the scale is changed to, the scale after the change is determined to match the detailed mode. If the scale after the change does not match the detailed mode, the process proceeds to S280, the scale of the current display mode (in this case, the wide area mode) is updated to the detailed side, and the process is temporarily terminated. On the contrary, if the scale after the change matches the detailed mode, the process proceeds to S250, and the above-described S1 is performed.
The display mode is switched from the current display mode (wide area mode in this case) to another display mode (detailed mode in this case) by the same procedure as the processing of 80, and the processing is temporarily terminated.

Here, the processing of S230 and S270 corresponds to the scale matching determination means of the present invention (claim 2),
The processing of S240 and S280 corresponds to the scale change executing means of the present invention (claim 2), and the processing of S250 corresponds to the switching command generating means of the present invention (claim 2).

That is, in the present embodiment, if the scale of the road map being displayed is changed as it is in accordance with the scale change command inputted from the outside, the scales in the respective display modes are the same and the VRAM 30a, Even if image data for displaying a road map of the same scale is stored in 30b and a road map switching command is input, it may not be possible to switch the road map displayed on the display device 4.
By the display map scale change processing, the scale of each display mode can be updated without matching the scale of each display mode.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment,
It can take various forms. For example, in the above-mentioned embodiment, when switching the road map displayed on the display device 4, the display switching SW 34 which outputs one of the outputs from the video controllers 32a and 32b to the display device 4 is used, but the VRAM 30a, VRAM3
If the output 0b is switched by the display switching SW, the road map can be displayed on the display device 4 by using one video controller.

In the above embodiment, the VRAMs 30a,
30b has been described separately from the RAM 16, but RAM1
Part of the area 6 may be used as VRAM. Further, in the above embodiment, the CD-ROM drive 6
After storing the map data from the
The data for one screen is cut out to the AMs 30a, 30b, but the RAM 16 is not used, but the data is directly stored in the VRAMs 30a, 30b from the CD-ROM drive 6, and the data for one screen is cut out by the video controller. Good.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a configuration of an entire navigation device according to an embodiment.

FIG. 2 is an explanatory diagram illustrating a configuration of map data stored in a CD-ROM.

FIG. 3 is a flowchart showing a map display process executed by a CPU.

FIG. 4 is a flowchart showing a display map scale changing process executed in S200 of FIG.

FIG. 5 is an explanatory diagram illustrating an example of a road map displayed on a display device and a switching operation thereof.

[Explanation of symbols]

2 ... GPS receiving unit 4 ... Display device 6 ... CD
-ROM drive 8 ... Remote control transmitter 10 ... Control device 12 ... CP
U 14 ... ROM 16 ... RAM 22 ... I / O 30a, 30b ... V
RAM 32a, 32b ... Video controller 34 ... Display switching SW

Claims (2)

[Claims] 1. A display unit for displaying a predetermined image including a road map, an image data storage unit for storing image data for displaying the predetermined image on the display unit, and the image data storage unit. Display control means for displaying an image on the display means based on the stored image data; and map data storage means for storing map data for displaying a road map on the display means for each road map of a different scale. A current position detecting means for detecting the current position of the vehicle; a scale commanding means for externally commanding a scale of a road map displayed on the display means; and a scale commanded from the scale commanding means from the map data storage means. Moreover, the map data of the predetermined area including the vehicle current position detected by the current position detection means is read out, and a mark indicating the vehicle current position is determined based on the map data. A vehicle map display device comprising: image data generation means for generating image data for displaying a road map including the image on the display means; and storing the image data in the image data storage means. A plurality of data generating means are provided, and a switching command means for externally instructing switching of the road map displayed on the display means is provided, and the display control means is any one of the plurality of image data storage means. Image data stored in one is selected, a predetermined image is displayed on the display unit, and when a map switching command is input from the switching command unit, the image data used for display is stored in another image data storage unit. And the scale of map data necessary for generating the image data is stored for each of the image data generating means. When a scale is commanded from the scale storage means and the scale command means, a scale for the image data generating means that is generating the image data being displayed on the display means among the scales stored in the scale storage means is set. A scale changing unit for changing the scale to the instructed scale, and each image data generating unit is configured to read the map data of the scale stored in the scale storing unit from the map data storing unit. A vehicle map display device characterized by the above. 2. The scale command means is configured to be capable of inputting a scale switching command for switching the scale of the road map displayed on the display means to a wide area side or a detail side, and the scale changing means is configured to perform the scale switching command. When the scale for the image data generating means that is generating the image data being displayed on the display means is changed in accordance with the above, the changed scale is the map data used by other image data generating means to generate image data. A scale matching determination unit that determines whether or not the scale matches, and when the scale matching determining unit determines that the scale after the change does not match the scale for another image data generating unit, the scale switching command is executed in accordance with the scale switching command. Scale change execution means for changing the scale stored in the scale storage means, and the scale after the change in the scale coincidence determining means matches the scale for other image data generating means. When cut off, a map switching command is output to the display control means, and the image data selected by the display control means is generated by another image data generation means determined to have the same scale. 2. The vehicle map display device according to claim 1, further comprising: a switching command generating unit that changes the display map to.