JPH0673159B2 - Vehicle navigation system - Google Patents

Description

TECHNICAL FIELD The present invention relates to a vehicle navigation device that displays a current position of a vehicle and a map on a screen of a display device and guides the vehicle to a destination.

[Conventional technology]

Recently, research and development of a vehicle navigation device that superimposes the current position of a vehicle such as an automobile on map information stored in a storage unit in advance and displays it on a screen of a display device to guide the vehicle to a destination has been actively conducted. Some of which have already been commercialized.

Such vehicle navigation device detects the current position of the vehicle by various sensors, and displays the position on the map,
The current position or map is moved as the vehicle travels. In an area with many roads such as an urban area, an enlarged map in the vicinity is displayed together with the current position.

[Problems to be Solved by the Invention] However, since the conventional vehicle navigation device only displays the current position of the vehicle on such a magnified map, an area where intersections are located in a complicated approach, etc. Was of little use in.

[Means for solving problems]

FIG. 1 is a block diagram of a vehicle navigation device of the present invention. In the figure, reference numeral 1 is an image file as a storage means for storing map information, which can be constituted by, for example, a CD-ROM, a video disk or the like. The image file 1 stores normal map information and information about main intersections included in the map information. The information on the intersection is stored as information for each approach road corresponding to the approach road to the intersection. Reference numeral 2 is a reading device for reading the information stored in the image file 1, decoding the information, and outputting the decoded information to the arithmetic unit 3 including a microcomputer. Reference numeral 4 is an arithmetic memory including a RAM for controlling programs for controlling the operation of the arithmetic unit and other necessary information such as RAM and ROM. Reference numeral 5 denotes sensors that detect data necessary for recognizing the current position such as the traveling speed, distance and direction of the vehicle.
The detection signal is supplied to the position recognition device 6 so that the current position is recognized. Information regarding the recognized current position is output to the arithmetic unit 3. Reference numeral 7 denotes an operation switch that is operated when a predetermined operation is commanded and input to the arithmetic unit 3. Reference numeral 8 is a main image memory, and 9 is a sub-image memory. The former constitutes storage means for storing map information out of the information read from the image file 1, and the latter stores information regarding intersections. The information stored in the main image memory 8 or the sub-image memory 9 is selectively selected by the switch 10 and displayed on the display device 11 such as a CRT or LCD.

[Action]

Then, the operation will be explained. The navigation by this apparatus is executed by the arithmetic unit 3 according to the flowchart shown in FIG. 5, for example. That is, when the vehicle is traveling toward a predetermined destination, the sensors 5 detect the data such as the traveling speed, distance and direction of the vehicle necessary for recognizing the current position by a known method. The detected data is supplied to the position recognition device 6 and the current position is recognized. The arithmetic unit 3 reads the map including the current position recognized by the position recognizing unit 6 from the image file 1 through the reading unit 2 and stores it in the main image memory 8 together with the current position. At this time, the arithmetic unit 3 switches the switch 10 to the main image memory 8
Since it is switched to the side, the map including the current position is displayed on the display device 11 together with the current position.

In such a state, the calculation device 3 calculates the distance between the current position and the main intersection where information is stored among the intersections on the map displayed on the screen. For example, as shown in FIG. 2, when intersections A to F are displayed on the screen as intersections storing information, the distance between these intersections and the current position on the way from the intersection B to the intersection E is Is calculated. Such calculation is performed based on the orthogonal coordinates (X, Y coordinates) of each point as shown in FIG. For example, for the distance 1 between the intersections A and B, the coordinates of the intersection A are (Xa, Ya),
When the coordinates of the intersection B are (Xb, Yb), 1 = {(Xa-Xb) ² + (Ya-Yb) ² } ^1/2 .

Then whether there is an intersection within a predetermined distance 1 ₂ predetermined from the current position (the circle indicated by numeral II in FIG. 2) is determined. Since the distance 1 ₂ When less is intersection is displayed on the display device 11 information related to the intersection, the sequence returns to the start. When there is no intersection distance 1 ₂ within, computing device 3 switches the switch 10 to the main image memory 8 side. Therefore, the map stored in the main image memory 8 remains displayed on the display device 11.

Then the calculation unit 3 determines whether there is an intersection a predetermined prescribed distance 1 ₁ within (the circle indicated by numeral I in FIG. 2). If there is no intersection at a predetermined distance 1 ₁ within, the sequence returns to the start. When there is an intersection at a predetermined distance 1 ₁ within, and the traveling direction match among the intersection, and the distance is searched shortest intersection is selected. For example, as shown in FIG. 3, when the intersection is an intersection having four entrance routes A to D, there are four pieces of information about the intersection corresponding to the entrance routes. That is, since approach road a is heading to the west-northwest (WNW), the image of the intersection seen from approach road a is stored together with the symbol WNW. Similarly, the image of the intersection seen from the approach road entrance along with the symbol SSW corresponding to the approach road heading to south-southwest (SSW) corresponds to the approach road toward southeast east (ESE) and the symbol E.
An image of the intersection seen from approach road C with SE, and an image of the intersection seen from approach road D together with symbol NNE corresponding to the approach road D further north-northeast (NNE) are stored. For example, the direction in which the vehicle is currently traveling is west-northwest (WN
W), the information of the intersection from the approach road A having the symbol WNW is searched and selected from the image file 1.

Further, it is determined whether the selected information is the information already stored (stored) in the sub-image memory 9. If the information is not yet stored, the information is read from the image file 1 and stored in the sub image memory 9. That is, when the intersection E approaching as the vehicle travels in FIG. 2 enters the circle indicated by the numeral I, the information of the intersection E as seen from the direction in which the vehicle is traveling is the sub-image memory. 9 is stored in advance.

When information in the sub-image memory 9 is stored, or when it is already stored, whether now there is an intersection distance 1 ₂ within is determined. The sequence when there is no intersection distance 1 within ₂ to return to the start. Distance 1 ₂ within switch 10 when there is an intersection is switched to the sub-image memory 9 side, information of the intersection is displayed on the display device 11. That is, when the intersection E enters the circle indicated by numeral II in FIG. 2, an image of the intersection E viewed from the direction of the intersection B is displayed.

The distance 1 ₁ and 1 ₂ the user can arbitrarily set by the operation switch 7.

The information about the intersection is not limited to the image information, and may be voice information or both. Further, information on a predetermined point other than the intersection can be displayed.

〔effect〕

As described above, according to the present invention, in the navigation device that detects the current position of the vehicle and displays the current position on the screen of the display device by superimposing the current position on the screen of the display device, the navigation device displays the current position on the screen. It is detected that the distance between the present position of the vehicle and the predetermined intersection has become equal to or less than a first predetermined value, and the corresponding detailed information of the predetermined intersection is selected from the first storage means, Since it is configured to notify that the selected detailed information is detected by detecting that the distance between and is less than or equal to a second predetermined value that is smaller than the first predetermined value, the predetermined distance is detected twice. By doing so, even if the selection time of the detailed information is different, for example, the arrival time of the address of the storage means in which the information of the predetermined intersection is stored is different, the detailed information is surely notified at the predetermined distance. The effect of being able to Having. This effect is important in a navigation device for a vehicle that moves at high speed.

[Brief description of drawings]

FIG. 1 is a block diagram of a vehicle navigation device of the present invention, FIGS. 2, 3, and 4 are schematic explanatory diagrams of map information thereof, and FIG. 5 is a flowchart thereof. 1 ... Image file, 2 ... Readout device 3 ... Calculation device, 4 ... Calculation memory 5 ... Sensors, 6 ... Position recognition device 7 ... Operation switch, 8 ... Main image memory 9 ... Sub Image memory, 10 …… Switch 11 …… Display device

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tadashi Masaji 3-3 Shinchi, Fuchu-cho, Aki-gun, Hiroshima Prefecture Mazda Co., Ltd. 216016 (JP, A)

Claims (1)

[Claims] 1. A navigation device for detecting a current position of a vehicle and displaying the current position on a screen of a display device by superimposing the current position on map information stored in advance, the vehicle being displayed on the screen. It is detected that the distance between the current position and the predetermined intersection becomes equal to or less than a first predetermined value, the detailed information of the corresponding predetermined intersection is selected from the first storage means, and the distance to the intersection is Second less than first predetermined value
The vehicle navigation device is characterized in that it detects that it has become less than or equal to a predetermined value and notifies the selected detailed information.