JPH03229288A - Map plotting device - Google Patents

Abstract

PURPOSE:To generate and display a head-up map image fast by providing a storage means stored with two map data on a detailed map and an outline map, a means which specifies which map is displayed according to the detailed or outline map data, a map image generating means, and a map display means. CONSTITUTION:A buffer memory 8 is stored with the detailed map data MPD and outline map data MPO which are read out of a CR-ROM 1. A system controller 7 reads the detailed and outline map data MPD and MPO on a section corresponding to a current vehicle position out of the CR-ROM 1 to the buffer memory 8, inputs the map data to a display device together with an azimuth theta, and performs control, etc., for a scrolled display corresponding to the travel of the vehicle. For example, a head-up image plane is displayed based on the outline map data during, for example, the movement of the vehicle and a nose-up still image plane is displayed based on the detailed map data while the vehicle is in a stop state. Consequently, head-up and scrolled map images are generated and displayed fast.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a map drawing device for an automobile navigation system, and particularly to a map drawing device that rotates and displays a map so that the direction of travel of a vehicle is directed upwards on a display screen. Regarding equipment.

<Prior Art> An automobile navigation system that uses a CD-ROM as a map data storage means stores a large amount of map data in the CD-ROM, and also has a display device and a position measuring device that measures the current position of the vehicle. etc.,
A map corresponding to the current position of the vehicle is displayed on a display screen, a mark (location cursor) indicating the current position of the vehicle is displayed on the map, and the mark is moved relative to the map as the vehicle travels.

The mark can be moved relative to the map by fixing the mark in the center of the display screen and scrolling the map in accordance with the movement of the vehicle. Sunarichi, mXn (for example, 3×3) adjacent map images MP in advance
As shown in FIG.
M), and when the vehicle moves, the corresponding V
Range for reading map data from RAM (window, -
Move the WD (indicated by the dotted chain line) to scroll the map on the display screen. Then, one or more scroll display processes are performed until the vehicle enters the adjacent area, and when the vehicle enters the adjacent area, new 3x3 adjacent map data is read out so that the center of the area into which the vehicle entered is located, and using these map data, 9 Generate a map image MP2 for the screen and use it in the second VR
Store in AM. After that, the map image is read from the specified window of the second VRAM and scrolled and displayed on the CRT.
The first step each time you enter a new area. 3×3 map images are alternately stored in the second VRAM, and the VRAM from which the map images are read is switched to continuously scroll and display the map.

When drawing a map in such a car navigation system, there are two methods: one is to draw the map so that the top of the display screen is north (north up), and the other is to draw the map so that the top of the display screen is the direction of travel of the vehicle. (head-up).The latter head-up drawing method has the advantage of making it easier to grasp the direction in which the vehicle is traveling and also making it easier to read the map.

<The problem that the invention aims to solve> However, with the head-up drawing method, a head-up map image must be generated and displayed on the display screen every time the traffic direction changes, so only one type of detailed map data can be generated. Conventional drawing devices that do not have a head-up map image take too much time to generate a head-up map image, making it impossible to display it at high speed, and there are also problems such as not being able to scroll smoothly when driving at high speed.

From the foregoing, an object of the present invention is to provide a map drawing device that can generate and display heads-up map images at high speed.

<Means for solving the problem> The above problem can be solved by two maps: a detailed map and a rough map.
a storage means for storing map data;

This is achieved by a means for specifying whether a map is to be displayed based on detailed or rough map data, a map image generation means, and a map display means.

<Function> Save two types of map data, a detailed map and a rough map, for example on a CD-
It is stored in a ROM, and it is specified whether a map is to be displayed on a display screen based on either detailed or general map data, and a heads-up map image is generated based on the specified map data and displayed on the display screen. for example,
While the car is moving.

A head-up screen is displayed based on general map data, and when the vehicle is stopped, a north-up still screen is displayed based on detailed map data.

<Embodiment> FIG. 1 is a block diagram of an automobile navigation system including a map drawing device according to the present invention.

In the figure, 1 is a CD-RO that serves as a map data storage means.
M, and two types of map data, a detailed map (see Figure 2 (a)) and a rough map (see Figure 2 (b)), are stored for each rectangular area with a predetermined longitude and latitude width. . The rough map shows main roads, main facilities, main characters, etc.
The amount of data is much smaller than detailed maps6
2 is an operation unit (not shown) for map search, enlarging/reducing,
Equipped with various keys for specifying detailed/outline maps, etc.

Reference numeral 3 indicates an orientation sensor (for example, a geomagnetic sensor) that detects the absolute direction, and 4 indicates a movement amount sensor, which includes a speed sensor that detects travel distance, a transmission sensor that detects forward and backward movement, and the like. 5 is a CPU for position calculation, and direction sensor 3. The current position (longitude, latitude) of the own vehicle is calculated and output based on the respective values input from the movement amount sensor 4. or,
The position calculation CPU 5 receives data SPD indicating whether the vehicle is stopped/moving based on the output of the movement sensor 4, and the direction sensor 3.
Outputs direction data DIR from .

6 is a processing device, which includes a system controller (CPU) 7, a map data buffer memory 8, etc., and the buffer memory 8 stores detailed map data MPD and rough map data MPO read from the CD-ROMI. It looks like this.

The system controller 7 controls (1) the car 1 [details of the area according to the right position, rough map data MPD, MPO3CD-
It reads out the map data from the ROMI to the buffer memory 8, inputs the map data together with the rotation angle (azimuth) O to a display device to be described later, and (2) performs control for scrolling display according to the running of the vehicle.

9 is a display device, and system controller 7
a coordinate conversion unit 10 that performs coordinate conversion of position data included in map data input from a rotation angle (azimuth) θ;
, an image generation unit 12 that generates a map image rotated by θ based on the position data obtained by coordinate transformation; The detailed map VRAM 13 stores map images, the first and second (7) VRAMs 14.15 store rough map images, and a predetermined VRAM window position designated by the system controller 7. It has a readout control section 16 that reads and outputs images, and a display section (cathode ray tube) 17.

The overall operation of FIG. 1 will be explained below. It is assumed that the vehicle is currently moving and a head-up map is being drawn based on the rough map data.

In advance, 3x3 outline map images are transferred to the first outline map VRA.
Deploy it to M14 and use VRAM1 as the vehicle moves.
The reading position (window position If) of the map data of step 4 is changed, and the general route map is scrolled on the display screen.

When the orientation of the vehicle changes during such scroll display, the system controller 7 inputs the orientation θ together with the map data to the display device 9, and also inputs a signal MID specifying the VRAM 14.

When the display device 9 receives these data,
Generate a general map image that looks like a heads-up
Store it in VRAM14. As a result, a rad-up map image is displayed thereafter, and a scroll display is performed with the head up in accordance with the movement of the vehicle.

In such a case, when the vehicle stops or when the display of a detailed map is requested from the operation unit 2, the system controller 7 displays the detailed map data,
Input the rotation angle θ (20) and the signal MID specifying the detailed view VRAM.

As a result, the display device 9 generates a detailed north-up map image and stores it in the VRAM 13. Then,
The system controller 7 sends the readout control unit 16 a VRA
M13 and its window position are specified, and the readout control unit reads out the detailed map image from the VRAM 13 and displays it on the display unit 17.

When the vehicle enters an adjacent area while the above heads-up display and scroll display are being performed, the system controller 7 reads a 3x3 image containing the adjacent area from the CD-ROM 2.
The details of the map and the rough map data MPD and MPO are read out and stored in the buffer memory 8, and then the rough map data, the rotation angle θ (=direction of the car), and the second VRAM 15 for the schematic map are specified. Display signal MID! f9, the display device generates a schematic map image of the adjacent area in a heads-up manner, and stores it in the second VRAM 15.

Next, the system controller 7 controls the readout control section 16.
, the second VRAM 15 for the schematic diagram and its window position are specified. The readout control unit 16 reads out the map image from the specified window of the second VRAML 5 and displays it on the CRT, and thereafter displays a head-up map image every time the direction of travel changes as described above, and also displays the head-up map image in accordance with the movement of the vehicle. to move the window position and scroll the display.

Then, each time you enter an adjacent area, the first and second
The general map images are alternately stored in the VRAMs 14 and 15, and the VRAM from which the map images are read is switched to continuously scroll and display the head-up general map.

Note that the above configuration is configured to detect whether the vehicle is moving or stopped using sensor signals and to switch the display between the general map and detailed map based on whether the vehicle is moving or stopped. It may also be configured such that the display can be switched only by a switching signal from a key operation from the unit 2, and the user can switch the display between a general map and a detailed map.

<Effects of the Invention> According to the present invention, two types of map data, a detailed map and a rough map, are stored in a CD-ROM, and a map can be displayed directly on the display screen based on either the detailed or rough map data. Since the configuration is configured to generate a head-up map image based on the specified map data and display it on the display screen, when using strategic map data, it is possible to quickly generate a head-up map image and a scrolling map image. If detailed map data is used, a desired detailed map can be displayed.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a navigation system including a map drawing device according to the present invention, and FIG. 2 is an explanatory diagram of a detailed map and a schematic map. FIG. 3 is an explanatory diagram of scroll display. 1...CD-ROM 7...System controller 9...Display device 13 -VRAM for detailed drawings 14.15--VRAM diagrams for first and second mechanical drawings (a) (b)

Claims (1)

[Claims] A map drawing device for an automobile navigation system that displays a map on a display screen and the current position of a vehicle on the map, comprising a storage means for storing two types of map data, a detailed map and a rough map, and a map for either the detailed map or the rough map. A specifying means for specifying whether a map is to be displayed on a display screen based on the data, a map image generating means for generating a map image based on the map data, and a display means for displaying a map image based on the specified map data. A map drawing device characterized by: