JP3011991B2 - In-vehicle navigator - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an in-vehicle navigator, and more particularly to an in-vehicle navigator capable of displaying a large amount of map information effective for a driver on a screen.

<Prior Art> There is an in-vehicle navigator that guides a vehicle and enables a driver to easily reach a desired destination. This in-vehicle navigator detects the current location of the vehicle and
The map data around the current position is read from the ROM, the map image is drawn on the V-RAM, the current position mark is drawn on the map image, and the image on the V-RAM is converted into a video signal and displayed on the CRT display screen. . Each time the current position changes due to the movement of the vehicle, the map image in the V-RAM is rewritten and the map on the screen is moved, so that the map information around the current position can always be understood at a glance.

FIG. 6 shows an example of a map screen in a conventional vehicle-mounted navigator. The circle A at the center of the screen is the current location mark, and the arrow B
Is a traveling direction mark of the vehicle viewed on the map. Arrow C
Is a preceding guidance mark at the time of route guidance, and guidance is displayed to indicate in which direction the vehicle should go in order to reach the destination.

<Problems to be Solved by the Invention> By the way, among the maps displayed on the screen, the map information of the vehicle driving direction is effective for the driver, but many of the conventional vehicle-mounted navigators are similar to FIG. Since the center of the screen is the current location, there is only half the effective map information given to the driver on the screen.

In order to avoid this drawback, a device has been proposed in which a point at a certain distance from the current location toward the destination is set as the center of the screen, and a large amount of map information in the direction of the destination is given (Japanese Utility Model Laid-Open No. 1-128121). Gazette).

However, in this prior art, it is good if the currently traveling road extends toward the destination as shown in FIG. 7 (1), but in an actual traveling scene, FIG. 7 (2)
In many cases, the road currently running extends in a direction that is significantly different from the direction of the destination to bypass the mountains, as shown in the figure.In such a case, the display range of the vehicle driving direction is rather narrowed, and the necessary map is required. There was a problem that information could not be obtained.

As described above, an object of the present invention is to provide an in-vehicle navigator capable of widening a display range of a vehicle traveling direction effective for a driver regardless of a direction of a road on which the vehicle is currently traveling.

<Means for Solving the Problems> According to the present invention, the present invention refers to storage means for storing map data, display means for displaying a map image, current position detection means for detecting a current position of a vehicle, and map data. And a preceding point calculating means for calculating a preceding point closer to the destination by a predetermined distance from the current position on the planned traveling route, and superimposing the current position mark on the map image such that the center of the screen becomes the preceding point based on the map data. This is achieved by providing a map display control means for displaying on the display means.

<Operation> According to the present invention, a preceding point closer to the destination by a predetermined distance from the current position on the planned traveling route with reference to the map data is calculated, and the center of the screen becomes the preceding point based on the map data. To display the current location mark on the map image on the display means. Thereby, regardless of the direction of the road on which the vehicle is currently traveling, the surface area in the vehicle traveling direction is widened, and a large amount of map information effective for the driver is provided.

<Embodiment> FIG. 1 is a block diagram of a main part of an on-vehicle navigator according to an embodiment of the present invention.

1 is a CD-ROM that stores map data, 2 is a CRT display that displays a current position mark, a traveling direction mark and a preceding guidance mark on a map image, and 3 is a device that detects the current position and azimuth of a running vehicle and obtains the current position data. A current position detection unit that outputs the traveling direction data.In this embodiment, the present position detection unit detects the current position from the vehicle direction and the traveling distance, but detects the current position using radio wave navigation such as GPS and Loran. May be. Reference numeral 4 denotes an operation unit for setting a departure place (in the case of integral navigation) and a destination at the time of departure. Reference numeral 5 denotes a microcomputer-based map display control device. Calculates the driving guidance route of the vehicle, calculates the preceding point a certain distance away from the current location toward the destination on the driving guidance route while traveling, and based on the map data, the center of the screen becomes the preceding point and the map image , A current position mark, a traveling direction mark, and a preceding guidance mark are superimposed and displayed on the CRT display 2.

Reference numeral 5a denotes a traveling guidance route calculation unit for simulating a traveling guidance route (optimum traveling route) by referring to the map data on the CD-ROM 1 from the departure point and destination information set by the operation unit 4 before starting traveling, and 5b. Calculates a preceding point and a course (direction) that should be the preceding point at a certain distance from the current position of the vehicle to the destination on the traveling guidance route during traveling, and displays preceding guidance display data (preceding point data and course data) In this embodiment, the distance is measured along the traveling guidance route, but it can be measured by a straight line distance.

6 is based on the map data, and the current location mark, the traveling direction mark,
This is a map display control unit that displays the leading guidance mark on the CRT display 2 in a superimposed manner. 6a is a map image drawing unit that reads map data of a wider area than the screen display area around the preceding point from the CD-ROM 1 based on the preceding point data and draws a map image in the buffer RAM of 6b, and the display area on the screen Sometimes, the buffer RAM 6b is partially rewritten as necessary so that does not exceed the image range of the buffer RAM. 6c
Is a cutout unit that cuts out a map image for one screen from the map image in the buffer RAM 6b and writes it in the V-RAM of 6d based on the preceding point data based on the preceding point, and changes according to the change of the preceding point due to the movement of the vehicle. , Sequentially rewrites the map image in the V-RAM 6d.

6e inputs the current position data, the traveling direction data, and the preceding guidance display data, and each time the map image of the V-RAM 6d is rewritten, the current position mark, the traveling direction mark, and the preceding guidance mark are displayed on the V-RAM 6d. A mark image drawing unit 6f is a video conversion unit that converts a video signal into a video signal while repeatedly reading image data from the V-RAM 6d and outputs the video signal to the CRT display 2.

FIG. 2 is a flowchart for explaining the map display operation of the map display control device 5, FIG. 3 is an explanatory diagram of a range of a map image drawn in the buffer RAM 6b, and FIG. 4 is an explanatory diagram of a display screen.

If the departure place and destination are set on the operation unit 4 before departure,
The departure location data is output to the current location detection unit 3 and used as the starting point of the current location detection. The travel guidance route calculation unit 5a performs a number of simulation calculations with reference to the map data on the CD-ROM 1 from the departure point data and the destination data, and searches for an optimal travel guidance route (steps 101 and 102).

Next, the preceding point calculation unit 5b inputs the current position data detected by the current position detection unit 3 and refers to the traveling guidance route data calculated by the preceding guidance route calculation unit 5a to move a predetermined distance from the current position to the destination. The distant preceding point and the course at the preceding point are calculated, and the preceding guidance display data including the preceding point data and the course data are displayed on the map image drawing unit 6a and the extracting unit 6.
c, Output to the mark image drawing unit 6e (step 103).

The map image drawing unit 6a includes one unit map including the preceding point,
The map data for the eight unit maps surrounding the map is read from the CD-ROM 1, and the map image is drawn in the buffer RAM 6b (step 104, see unit maps a to i in FIG. 3A). Here, one unit map corresponds to the size of one screen. Subsequently, the cutout unit 6c cuts out a map image for one screen centered on the preceding point from the buffer RAM 6b and writes it into the V-RAM 6d (step 105, see the broken line area in FIG. 3 (1)).

Next, the mark image drawing unit 6e draws a circled current position mark image on a predetermined location of the map image on the V-RAM 6d corresponding to the current position based on the current position data, and travels next to the current position mark based on the traveling direction data. The traveling direction mark image of the arrow is superimposed and drawn in the direction indicated by the direction, and based on the preceding guidance display data, the leading guidance of the arrow in the direction indicated by the route data is provided at the center of the map image on the V-RAM 6d indicated by the preceding point data. The mark image is overlaid and drawn (step 106).

The image of the V-RAM 6d is repeatedly read out by the video conversion unit 6f, converted into a video signal, output to the CRT display 2, and displayed with the current position mark A, the traveling direction mark B, and the preceding guidance mark C superimposed on the map. (Step 10
7, see FIG. 4 (1)).

The preceding point calculation unit 5b receives the current position data from the current position detection unit 3 and determines whether or not the current position has changed due to the movement of the vehicle (step 108).
Subsequently, it is determined whether or not the vehicle has arrived at the destination (step 109). If the vehicle has arrived, the process is terminated. The route at the preceding point is calculated, and the preceding guidance display data is output (step 110).

Map image drawing unit 6a that inputs new preceding point data
Determines whether the preceding point of the map image written in the buffer RAM 6d deviates from one unit map a in which the preceding point has been located (step 111), and if not, the map image is not rewritten. (See FIG. 3 (2)), the image of one unit map b to which a new preceding point enters and eight unit maps c to l surrounding this unit map are buffered.
A part of the map image is rewritten so as to exist on the RAM 6b (step 112, see FIG. 3 (3)).

Next, the cut-out section 6c in which new preceding point data is input
However, a map image for one screen centered on the new preceding point is cut out from the buffer RAM 6b and written into the V-RAM 6d (step 105, see the broken line area in FIG. 3 (3)). Then, the mark image drawing section 6e draws the current position mark, the traveling direction mark, and the preceding guidance mark image corresponding to the new current position in an overlapping manner (step 106).

The image in the V-RAM 6d is repeatedly read out by the video conversion unit 6f, converted into a predetermined video signal, and output to the CRT display 2, so that the traveling guidance screen is changed by an amount corresponding to the movement of the vehicle.

Hereinafter, in the same manner, the V-RAM 6
Since the map image and the mark image on d are rewritten, the driving guidance display on the screen changes accordingly.

Note that the preceding point calculation unit 5b generates preceding guidance data with the destination itself as a preceding point when the vehicle is near the destination and a point that is a certain distance from the current location on the driving guide route exceeds the destination. I do.

According to this embodiment, when the road on which the vehicle is currently traveling is facing the destination, as shown in FIG. 4 (1), the vehicle travel direction is displayed in a wide range on the screen as in the conventional case. In addition, even when the road on which the vehicle is currently traveling is in a direction different from the destination direction at that point due to, for example, bypassing the mountains, the screen is displayed as shown in FIG. 4 (2). Indicates that the vehicle travel direction is displayed in a wide range.

In the above-described embodiment, the case where the preceding guidance mark is displayed at the preceding point in the center of the screen has been described as an example. However, the present invention is not limited to this, and the preceding guidance mark is displayed as shown in FIG. C is a point closer to the current position than the preceding point in the center of the screen (see x in FIG. 5 (1)), or displayed at a point farther from the preceding point in the center of the screen when viewed from the current position as shown in FIG. 5 (2). Or the preceding guidance mark may not be displayed.

The simulation calculation of the travel guidance route is performed at one time before the start of travel, but the travel guidance route from the current position to the destination and the preceding point may be sequentially calculated during travel.

<Effects of the Invention> As described above, according to the present invention, storage means for storing map data, display means for displaying a map image, current location detection means for detecting the current location of a vehicle, and a planned traveling route with reference to the map data In the above, the preceding point calculating means for calculating the preceding point closer to the destination by a certain distance from the current location, and based on the map data, the current location mark is superimposed on the map image so that the center of the screen becomes the preceding point, and the display means A map display control means for displaying, and calculating a preceding point closer to the destination by a predetermined distance from the current position on the planned traveling route with reference to the map data, and based on the map data, the center of the screen becomes the preceding point. In this way, the present location mark is superimposed on the map image and displayed on the display means. More useful map information will be given to the translator, and convenience will be increased.

[Brief description of the drawings]

FIG. 1 is a block diagram of a main part of an on-vehicle navigator according to an embodiment of the present invention, FIG. 2 is a flowchart showing the operation of a map display control device in FIG. 1, and FIG. 3 is a drawing of a buffer RAM in FIG. FIG. 4 is an explanatory view of a display screen according to an operation of the present invention, FIG. 5 is an explanatory view of a display screen according to a modification of the present invention, and FIG. 6 is a conventional in-vehicle navigator FIG. 7 is an explanatory view of a display screen in another conventional in-vehicle navigator. DESCRIPTION OF SYMBOLS 1 ... CD-ROM 2 ... CRT display 3 ... Current position detection part 4 ... Operation part 5 ... Map display control device 5a ... Driving guidance route calculation part 5b ... Private point calculation part 6 ... Map display control Department

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields investigated (Int. Cl. ⁷ , DB name) G01C 21/00 G08G 1/0969 G09B 29/00-29/10

Claims (1)

(57) [Claims] 1. A storage means for storing map data, a display means for displaying a map image, a current location detection means for detecting a current location of a vehicle, and a predetermined distance from a current location on a planned traveling route by referring to the map data. Preceding point calculation means for calculating a preceding point only near the destination; map display control means for displaying the current position mark on the map image on the display means so that the center of the screen becomes the preceding point based on the map data; An in-vehicle navigator comprising: