JPH06300575A - Running position display device - Google Patents

Abstract

PURPOSE:To automatically change reduction scale of a map by computing the distance between the own car position and the next crossing in the advancing direction on the present running road, and judging whether the distance range can be simultaneously displayed in the present reduction scale or not. CONSTITUTION:When reduction scale of a display map is selected, the map display data is read out from CD-ROM 7. The position and direction of the own car on the road network are decided by the read road network data and the present position data obtained by a CPU 10. Next, the straight distance between the own car position obtained by the CPU 10 and a next crossing in the advancing direction on the present running road is computed, and it is judged whether the next crossing is contained in the display screen by the present reduction scale display or not. When the distance from the present position to the next crossing is judged to be longer than a decided value, a map display data of reduction scale in which the next crossing on the present running road is contained in the display screen is read from the ROM 7 so as to make the map on the screen, and further the own car mark is displayed on the displayed map.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling position display device for displaying the current position of an automobile or the like on a display device together with a map.

[0002]

2. Description of the Related Art FIG. 1 shows an outline of an on-vehicle traveling position display device. In FIG. 1, 1 is a direction sensor,
The direction sensor 1 uses a geomagnetic sensor for detecting the absolute traveling direction of the automobile and an optical gyro for detecting the relative traveling direction of the automobile. Reference numeral 2 is a distance sensor that generates a pulse according to the number of rotations of the wheel, and 3 is various sensor signals such as an ON / OFF signal of a brake switch and a parking switch, and a power supply voltage monitoring signal. Reference numeral 4 is a sensor signal processing unit that processes sensor signals from the azimuth sensor 1, the distance sensor 2, and the like, and 5 is a GPS (Global Positioning System) receiver. The GPS receiver 5 receives radio waves transmitted from a plurality of satellites and performs calculation. By doing so, the position (latitude, longitude) of the receiving point can be obtained. Reference numeral 6 denotes a CD-ROM drive, and this CD-ROM drive 6 reads map data from a CD-ROM 7 in which map data is recorded. Reference numeral 8 denotes a display / operation unit installed in the vehicle interior. The display / operation unit 8 is provided on a liquid crystal display 8A for displaying a map and the current traveling position, direction, etc. of the automobile, and is provided in front of the liquid crystal display 8A. The touch panel 8B includes a switch for instructing enlargement or reduction of the display map,
A switch for instructing a route search, a switch for selecting a destination from the place names displayed on the liquid crystal display 8A, and the like are provided. Reference numeral 9 denotes an apparatus main body, and the apparatus main body 9 is installed in a trunk room or the like.

Next, the structure of the apparatus main body 9 will be described.
Reference numeral 10 denotes a CPU (central processing unit) for performing various calculations, 11
Is a ROM (read only memory) in which programs for various calculations performed by the CPU 9 are stored, 12 is data from the direction sensor 1, distance sensor 2, GPS receiver 5, CD-ROM drive 6 and the like, calculation results by the CPU 10, etc. Is a memory (DRAM) for storing data, 13 is a backup memory (SRAM) for holding necessary data even when power supply to the apparatus body 9 is stopped, and 14 is a character displayed on the liquid crystal display 8A. A memory (kanji, font ROM) in which patterns such as symbols are stored, 15 is an image processor for forming a display image based on map data, current position data of the vehicle, and 16 is output from the image processor 15. Map data, current position data and Kanji, Kanji such as town names and road names output from the font ROM 14, fonts The liquid crystal display 8 the door synthesized and
A memory (VRAM) for storing the image to be displayed on A, 17
Is an RGB conversion circuit for converting the output data of the VRAM 16 into a color signal, and the converted color signal is output from the RGB conversion circuit 17 to the liquid crystal display 8A. 18
Is a communication interface. Liquid crystal display 8A
As shown in FIG. 2, a peripheral map of the current position of the vehicle is displayed together with the town name, and a vehicle mark 19 for displaying the current position of the vehicle is displayed in the displayed map.

FIG. 4 shows the format of data stored in the CD-ROM 7, where 20 is a disc label and 2 is a disc label.
1 is a drawing parameter, 22 is leaf management information, 23, 24
Is a figure leaf, and in this figure leaf, background data, character data,
Road data and the like are stored, and data for each unit map obtained by dividing the topographic map of Japan by latitude and longitude is stored. In the map leaf, a map leaf (level 2) that roughly describes a wide region to a map leaf (level 0) that describes a narrow region in detail are set. Each map leaf is composed of view sets A, B, and C that describe the same area. In the view sets A, B, and C, B is described more than A and C is described in more detail than B. Each view set A, B, C is composed of view set management information and a plurality of units. The unit describes a divided area obtained by dividing the area of each view set into a plurality of areas, and each unit includes a unit header, a character layer, a background layer, a road layer, an option layer, and the like. Place names, road names, facility names, etc. displayed on the map are recorded in the character layer, data for drawing roads, facilities, etc. are recorded in the background layer, and the road layer is as shown in FIG. In the table, data on coordinate points (nodes) and lines (links) that describe roads including intersections, for example, node numbers of nodes, latitude, longitude, link numbers of links, link distances, etc. are stored. In FIG. 5, circles (∘) indicate nodes, and lines between the nodes indicate links. A black circle (●) with a node number of 4 indicates an intersection node. The data recorded in the road layer is not directly involved in the map display and is used as road network information such as map matching.

In FIG. 1, the output of the azimuth sensor 1 and the output of the distance sensor 2 are sent to the CPU 10 via the sensor processing unit 4.
Sent to. The CPU 10 calculates the current position of the vehicle and obtains the latitude and longitude of the current position. Also GPS
The current position is corrected based on the data from the receiver 5. Based on the present position thus obtained, the map data of the unit corresponding to the present position is read from the CD-ROM 7 by the CD-ROM drive 6, and this map data is stored in the memory (DRAM) 12 via the communication interface 18. Is stored. A part of the map data stored in the DRAM 12 is read by the CPU 10,
It is converted into image data by the image processor 15 and written in the image memory 16. The image data stored in the image memory 16 is converted into a color signal by the RGB conversion circuit 17 and sent to the liquid crystal display 8A, and a map of a predetermined range centering on the current position is displayed. Further, if the map data read from the DRAM 12 includes character codes and symbol codes, patterns corresponding to these character codes and symbol codes are read from the kanji and font ROM 14, so that the liquid crystal display 8A displays a place name etc. together with the map. Symbols such as letters and schools are displayed. In addition, based on the traveling speed and traveling direction that are sequentially obtained as the automobile travels,
The current position displayed on the liquid crystal display 8A is sequentially changed.

FIG. 2 shows a display example of the liquid crystal display 8A. A road map, a place name, an intersection name, a road name, etc. are displayed. In FIG. 2, reference numeral 19 indicates a vehicle mark of the vehicle, and this vehicle mark 19 indicates the current position and traveling direction of the vehicle.

Next, the map display operation of the above conventional example will be described with reference to FIG. As shown in FIG. 7, Step A
The scale of the map displayed on the liquid crystal display 8A is selected with. In step B, the selected scale map display data is read from the CD-ROM 7. In step C, a map is drawn on the liquid crystal display 8A based on the data read by the CD-ROM 7. Next, in step D, the CD-ROM
The road network data recorded in the road layer is read from 7 and the road network data and the CPU are read.
The position and azimuth of the own vehicle are determined from the current position data obtained by calculation in step 10 (step E), and the own vehicle mark 19 is displayed on the map displayed on the liquid crystal display 8A in step F. FIG. 2 shows a display example on the liquid crystal display 8A in the conventional example.
9 indicates that the road R is traveling.

However, in the above-mentioned conventional example, at the selected scale, as shown in FIG. 2, the intersection next to the road R on which the vehicle is currently traveling may not be displayed. It is not clear whether or not the vehicle will reach the next intersection if the vehicle travels a long distance. By operating the wide area switching button displayed on the screen and turning on the touch switch 8B,
I had to switch to the wide area map shown in FIG.

[0009]

As described above, in the conventional example, the vehicle position and the next intersection may not be displayed on the screen at the same time depending on the selected scale, so that the next intersection may be displayed. In that case, there has been a drawback that the wide area switching button has to be manually operated to switch and display the wide area map.

The present invention eliminates the above-mentioned drawbacks of the prior art, and enables automatic display up to the next intersection of the road on which the vehicle is currently traveling without manually switching the scale of the map displayed on the liquid crystal display. Another object of the present invention is to provide a traveling position display device capable of automatically changing the scale of a map.

[0011]

In order to achieve the above object, the present invention corresponds to a vehicle position detecting means for detecting a vehicle position and a vehicle position detected by the vehicle position detecting means. Means for reading the map data from the storage means, means for displaying the map on the display means based on the read map data and means for displaying the vehicle position detected by the vehicle position detecting means, and A determination means for calculating the distance between the vehicle position on the road and the next intersection in the traveling direction, and determining whether the vehicle position and the next intersection can be simultaneously displayed on the display screen of the display means at the current display scale. And a scale automatic changing unit for automatically changing to a display scale that can be simultaneously displayed when it is determined by the determination unit that the vehicle position and the next intersection cannot be displayed at the same time.

[0012]

The present invention is constructed as described above, and calculates the distance between the own vehicle position detected by the own vehicle position detecting means and the next intersection on the road on which the vehicle is currently traveling, and obtains from this calculation. If it is determined that the vehicle position and the next intersection cannot be displayed on the display screen at the same time from the determined distance, the display scale is automatically changed and the vehicle position and the next intersection are displayed on the display screen. It is displayed at the same time.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS.
Will be explained together. FIG. 6 shows a map display process according to an embodiment of the present invention. In FIG. 6, when the scale of the displayed map is selected in step A, the map leaf and the view set are selected according to the selected scale, the unit corresponding to the own vehicle position is selected, and the map display data is CD- ROM
7 is read (step B). In the next step C, the road network data (FIG. 5) recorded in the road layer of the CD-ROM 7 is read (step C), and the road is read from the read road network data and the current position data obtained by the CPU 10. The vehicle position and direction on the network are determined (step D). Next, in step E, it is determined whether or not the current display mode is a mode in which the next intersection of the road on which the vehicle is currently traveling is displayed. When the mode for displaying the own vehicle position including the next intersection is selected by the operation button, the process proceeds to step F, and the straight line between the own vehicle position obtained by the CPU 10 and the next intersection X in the traveling direction of the road on which the vehicle is currently traveling. Calculate the distance. Intersection X
Is recorded on the road layer of the CD-ROM 7 shown in FIG. 4, and a straight line between the current position of the own vehicle and the intersection X is calculated from the coordinates of the intersection and the coordinates of the current position of the own vehicle. Distance is required. Next, in step G, it is determined whether or not the next intersection X is included in the display screen in the current scale display. In the present embodiment, the vehicle position is displayed in the center of the display screen. Therefore, in the determination in step G, for example, the straight line distance obtained in step F is 1/2 of the distance L above and below the current display screen. This is obtained by determining whether or not it is longer, and if it is determined that the distance between the current position obtained in step F and the next intersection X is longer than 1/2 of the distance L, the process proceeds to step H. Go to the next crossing X on the road you are currently traveling in
The map is read from the D-ROM 7, the map is drawn based on the data read in step I (FIG. 3), and the vehicle mark 19 is displayed on the displayed map in step J. If step E in FIG. 6 is determined to be no,
Alternatively, if YES in step G, the process proceeds to step I.

As described above, according to the present embodiment, as shown in FIG. 3, a map of a scale in which the next intersection X on the currently running road is automatically entered without automatically changing the scale. Since it is selected and displayed, it is possible to easily determine how far the vehicle should travel from the current position to reach the next intersection.

[0015]

According to the present invention, the scale is automatically changed so that the next intersection of the road on which the vehicle is currently traveling can be displayed without manually changing the scale of the displayed map. Therefore, there is an advantage that a user's manual operation is not necessary and the user can concentrate on driving. In addition, the user can see the displayed map
It is possible to easily determine how much distance the vehicle is currently traveling on to reach the next intersection.

[Brief description of drawings]

FIG. 1 is a block diagram of a traveling position display device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a display example of a liquid crystal display of the same embodiment.

FIG. 3 is a diagram showing a display example of a liquid crystal display of the same embodiment.

FIG. 4 is a diagram showing a format of a CD-ROM of the same embodiment.

FIG. 5 is a diagram showing road data recorded in a CD-ROM of the same embodiment.

FIG. 6 is a flowchart of display processing according to the embodiment.

FIG. 7 is a flowchart of display processing in a conventional example.

[Explanation of symbols]

 1 Direction Sensor 2 Distance Sensor 5 GPS Receiver 6 CD-ROM Drive 7 CD-ROM 8 Display / Operation Unit 8A Liquid Crystal Display 8B Touch Panel 9 Device Main Body 10 CPU 15 Image Processor

Claims (1)

[Claims] 1. A vehicle position detecting means for detecting a vehicle position, a means for reading map data corresponding to the vehicle position detected by the vehicle position detecting means from a storage means, and the read map data. Between the means for displaying the map on the display means based on the display means and the vehicle position detected by the vehicle position detection means, and the next intersection in the traveling direction of the vehicle position on the currently running road. A determination unit that calculates the distance and determines whether the vehicle position and the next intersection can be simultaneously displayed on the display screen of the display unit at the current display scale, and the determination unit simultaneously determines the vehicle position and the next intersection. A traveling position display device comprising: automatic scale reduction means for automatically changing to a display scale that can be simultaneously displayed when it is determined that the display cannot be performed.