JPH07318358A - Route search and display apparatus - Google Patents

Abstract

PURPOSE:To display the name, the symbol and the like of a specific point existing within a prescribed range by making use of a destination as the center and to easily run a vehicle up to the destination from the termination of a guidance route when it is judged that a present position found by a present-position arithmetic means is situated within the range of a definite distance from the destination. CONSTITUTION:A CPU 10 reads out a map on the basis of the present position of an own vehicle, and it displays the map on a liquid-crystal display 8A. In addition, a guidance route which is selected by a route search is displayed on the map which has been displayed on the display 8A, the position of the own vehicle is displayed on the map, and a mark indicating the direction of a destination is displayed. Then, it is judged whether the present position is situated within a definite distance with reference to the destination. When it is judged that the present position is not situated within the definite distance, an operation is returned to an initial operation. On the other hand, when it is judged that the present position is situated within the definite distance, the display scale of the map is changed in such a way that the position of the own vehicle and the desitnation are displayed on the same screen, and names of a crossing and an institution which are situated inside the display screen of the display 8A are displayed.

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 a current position of an automobile or the like on a display device together with a map, and more particularly, a route search display device for searching a route to a destination and displaying the searched route on the display device. Regarding

[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 a CPU 10
Map data, current position data and kanji output from
A memory (VRAM) for memorizing an image to be displayed on the liquid crystal display 8A by synthesizing Chinese characters such as a town name and a road name output from the font ROM 14 and a font, and 17 is a VRA
This is an RGB conversion circuit for converting the output data of M16 into a color signal, and the color signal is output from the RGB conversion circuit 17 to the liquid crystal display 8A. Reference numeral 18 is a communication interface.

FIG. 2 shows the format of data stored in the CD-ROM 7, 21 is a disc label, and 2 is a disc label.
Reference numeral 2 is drawing parameters, 23 is map leaf management information, and 24 is map leaf. Background data, character data, road data, etc. are stored in this map leaf 24, and a topographic map of Japan is represented by latitude and longitude. Data for each divided unit map is stored. In the map leaf 24, a map leaf that roughly describes a wide region is set to a map leaf that describes a narrow region in detail. Each map leaf is a map display level A, B, C that describes the same area.
It consists of Map display levels A, B, C are A
B and C are described in more detail than B and B, respectively. Each map display level A, B, C is composed of map display level management information and a plurality of units. The unit describes a divided area obtained by dividing the area of each map display level 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. In the character layer, the place name displayed on the map,
Road names, facility names, etc. are recorded.
Data for drawing facilities and the like is recorded, and in the road layer, as shown in FIG. 3, data on coordinate points (nodes) and lines (links) that describe roads including intersections, for example, node numbers of nodes. , Latitude, longitude, link number of link, link distance, etc. are stored. In FIG. 3, circles (∘) indicate nodes, and lines between the nodes indicate links. Also, 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,
It is used as road network information for map matching. In FIG. 2, reference numeral 25 denotes route search data. In the route search data 25, search data is recorded for each layer from a layer 0 for a narrow area to a layer n for a wide area. The search data of each layer is composed of node connection data 26, assumed link transit time (link cost) data 27, and route display data 28.
The node connection data 26 is, as shown in FIG.
Data indicating which node g, x, y is connected to. For example, for node c, nodes a, d,
It is data indicating that it is connected to f and y. Further, the link cost data 27 indicates the link cost of the link between the nodes as shown in FIG. 4. For example, the link cost of the link between the node a and the node c is “5”, and the node a The link cost of the link between the node b and the node b is “10”, and the link cost of the link between the node a and the node d is “20”. The link cost is obtained from link cost = link distance / set speed, and the set speed is set according to the road type and the road width, for example, as shown in FIG. The route display data 28 is recorded with data for displaying the route selected by the route search on the display map.

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, and the liquid crystal display 8A displays characters such as place names together with the map. , Symbols such as school are displayed. In addition, the current position displayed on the liquid crystal display 8A is sequentially changed based on the traveling speed and traveling direction that are sequentially obtained as the automobile travels.

Next, a conventional route search operation will be described with reference to FIGS. When the route search switch on the touch panel 8B is operated, the route search process is executed. First, as shown in FIG. 7, the destination is set in step A. The destination can be set by, for example, inputting the address of the destination or by using the liquid crystal display 8
This is done by designating a point on the map displayed in A. In step B, it is determined whether or not to start the route search. This determination is made based on whether or not the route search switch on the touch panel 8B of the display device 8 is operated. If it is determined in step B that the route search switch has been operated, the process proceeds to step C and route search is performed. In this route search, as shown in FIG. 4, the link costs of all routes from the origin (current position node) X to the destination node Y are added, and the route with the lowest link cost is selected. In case of 4, link X → a → c → d → f → g → Y
Total link cost of (10 + 5 + 5 + 5 + 5 + 5 = 3
5) is the smallest, so link X → a → c → d → f
The route connecting → g → Y is selected. The route selected in step C of FIG. 7 is displayed in red, for example, on the display map of the liquid crystal display 8A in step D.

FIG. 8 is a step C of route search in FIG.
8 is shown in more detail. In FIG. 8, first, in step a, a departure node and a destination node that are closest to the positions of the departure place and the destination are selected. In FIG. 4, node X
Indicates that the node is selected as the starting node and the node Y is selected as the destination node. Next, in step b, the route search data including the departure node X is read from the CD-ROM 7,
In step c, the route search on the departure side is performed. As described above, this route search selects the route with the lowest total link cost. Next, in step d, as a result of the search in step c, it is determined whether or not the target node is connected. If the distance from the starting point to the destination is relatively short and the destination node Y is included in the data read from the CD-ROM 7 in step b, it is determined as yes in step d, but the starting point is If the destination is far from, it is determined as no in step d and the process proceeds to step e. In step e, the route search data including the destination node Y is read from the CD-ROM 7, and in step f the route search on the destination side is performed. In step g, it is determined whether or not the route selected by the route search on the destination side in step f is connected to the search route on the departure side. If the result of this determination is NO, the search hierarchy is increased by one rank in step h in FIG. If the read data in steps b and e is the route search data of layer 0, the rank is increased to layer 1 in step h. Next, in step i, the starting node and the destination node are reset, and the process returns to step b.

In FIG. 6, the distance between the starting point and the destination is long,
It is the figure which showed the operation | movement when it is determined by step d and step g in FIG. 8 with no comprehension, and the route selected by the route search of the departure side is not connected to the destination node,
If the route selected in the route search on the destination side is not connected to the route searched in the route search on the departure side, the hierarchy 1
The route search data 29 is read and the departure node 30 and the destination node 31 are set. When the route indicated by the solid line is searched by the route search in the layer 1, step d in FIG.
If the answer is YES in step j, the process proceeds to step j, the route from the departure point to the destination is constructed in step j, the display data of the route searched in step k is created, and the route search is ended.

In FIG. 3, the thick line indicates the guide route selected as a result of the route search, and the node 1 of the unit 2
→ 2 → 3 → 4 → 5 → 6 → node 1 of unit 1 → 2 → 3
→ 4 indicates that the route is the selected guide route.

FIG. 12 shows the conventional liquid crystal display 8 described above.
The display example in A is shown. In FIG. 12, a broken line a is a guide route selected by the route search, b is a mark indicating a destination, and c is a mark indicating a vehicle position. CD-
Since the recording capacity of the ROM 7 is limited, the data of links and nodes shown in FIG. 3 is limited to the main roads. For this reason, as shown in FIG. 12, the guide route a selected by the route search is limited to the node of the main road near the destination b, and the guide route a may not be displayed up to the destination b. In this case, from the end of the guide route a to the destination b,
It was not possible to drive with reference to the guide route a, and it was necessary to drive at the discretion of the driver.

[0011]

As described above, in the above-mentioned conventional example, there is a problem that the driver must make a decision when the guide route searched by the route search does not reach the destination. It was

The present invention solves the above-mentioned conventional problems, and provides a route search display device capable of easily traveling from the end of a guide route to a destination.

[0013]

The first invention of the present invention is as follows:
In order to achieve the above object, a storage means in which road data is recorded, a current position calculation means for detecting the current position of the vehicle based on the traveling speed and traveling direction of the vehicle, and the data read from the storage means Display means for displaying the road map and the current position obtained by the current position calculation means, destination input means for inputting a destination, and a route to the destination input by the destination input means are searched. The route search means for displaying on the display means, the distance determination means for determining whether the current position obtained by the current position calculation means is within a certain distance range from the destination, and the distance determination means. When it is determined that the current position is within a certain distance range from the destination, the names of specific points existing within the predetermined range centering on the destination and the names of specific points such as symbols are displayed on the display means. It is characterized in that.

According to a second aspect of the present invention, in the first aspect, the destination direction is determined based on the current position determined by the current position calculation means and the destination input by the destination input means. A feature is that a direction display means for displaying the ground direction on the display means is added.

According to a third aspect of the present invention, when the distance determining means determines that the current position is within a certain distance range from the destination, the vehicle position and the destination are displayed on the same screen of the display means. As described above, a scale automatic switching means for automatically switching the scale of the displayed map is provided.

[0016]

According to the first aspect of the present invention, when the current position is within a certain distance range from the destination even after passing through the end of the route searched by the route searching means in the first invention. Further, since the name of the intersection is displayed on the display means, the destination can be easily reached by referring to the displayed name of the intersection.

In addition, in the second invention of the present invention, since the destination direction can be displayed in addition to the first invention, the destination direction can be easily grasped even when the destination is not displayed on the screen of the display means. In addition, when approaching the destination, the direction of the destination is displayed on the display means together with the name of the intersection near the destination, so that the destination can be reached more easily.

According to a third aspect of the present invention, when the current position is within a certain distance range from the destination, the map scale reduction is automatically switched by the scale automatic switching means.
The own vehicle position and the destination are displayed on the same screen of the display means.

[0019]

EXAMPLE An example of the present invention will be described below with reference to FIG. The route search processing of this embodiment is as shown in FIGS. FIG. 9 shows a process of displaying the vehicle position in this embodiment. In FIG. 9, in step 1, the map is read out based on the current vehicle position and displayed on the liquid crystal display 8A. In step 2, the guide route selected by the route search is displayed on the map displayed on the liquid crystal display 8A. Next, in step 3, the position of the vehicle is displayed on the map displayed on the liquid crystal display 8A, and a mark indicating the direction of the destination is displayed.
In the next step 4, it is determined whether or not the current position is within a certain distance with respect to the destination. If it is determined in this determination that the vehicle is not within the fixed distance, the process returns to step 1. On the other hand, when it is determined in step 4 that the current position is within a certain distance from the destination, the process proceeds to step 5 and the display scale of the map is changed so that the vehicle position and the destination are on the same screen. Next, in step 6, the names of intersections and facilities within the display screen of the liquid crystal display 8A are displayed. FIG. 10 shows a display example on the liquid crystal display A of this embodiment. In FIG. 10, a broken line a is a guide route selected by the route search, c is a mark indicating the position of the vehicle, d is a mark indicating the direction of the destination, and when the distance to the destination is relatively long, As shown in 10, the destination is not displayed on the same screen. FIG. 11 shows a display example in the above embodiment. The display shown in FIG. 11 shows that the current position is within a certain distance range from the destination in step 4 of FIG. 9 (within the circle e shown in FIG. 11).
The result is that the vehicle position and the destination are displayed on the same screen as a result of executing Step 5 and Step 6 and within a predetermined range from the destination within the map displayed on the screen (see FIG. 11). The name of the intersection inside the circle f)
"Intersection", "XX intersection", "△△ intersection", ▽▽ intersection and the symbol "〒" of the facility are displayed. As described above, according to the present embodiment, when the vehicle position comes out from the end of the guide route a, the intersection name and the like are displayed on the liquid crystal display 8A as shown in FIG. 11, so that the driver can display on the liquid crystal display 8A. The destination can be easily reached by referring to the displayed intersection name and the like.

[0020]

The present invention has the above-described structure. In the first aspect of the invention, the name of an intersection or the like is displayed on the display means even if it passes through the end of the route searched by the route search means. Therefore, the destination can be easily reached by referring to the displayed intersection name and the like. The second aspect of the present invention
In the invention, since the destination direction can be displayed in addition to the first invention, the destination direction can be easily grasped even when the destination is not displayed in the screen of the display means, and when the destination is approached, Since the destination direction is displayed on the display unit together with the name of the intersection near the destination and the like, there is an advantage that the destination can be reached more easily. Further, according to the third aspect of the present invention, when the current position is within a certain distance range from the destination, the own vehicle position and the destination are displayed on the same screen of the display means. This has the advantage that the route to the destination can be easily grasped.

[Brief description of drawings]

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

FIG. 2 is a format diagram of a CD-ROM of the same embodiment.

FIG. 3 is a road data diagram recorded in the CD-ROM of the same embodiment.

FIG. 4 is a route diagram illustrating a route search method of the same embodiment.

FIG. 5 is a display diagram showing set speeds for link cost calculation in the embodiment.

FIG. 6 is a hierarchical structure diagram for route search in the same embodiment.

FIG. 7 is a flow chart of route setting in the embodiment.

FIG. 8 is a flow chart of route search according to the embodiment.

FIG. 9 is a flowchart showing the operation of the embodiment.

FIG. 10 is a display diagram of the liquid crystal display of the same embodiment.

FIG. 11 is a display diagram of the liquid crystal display of the same embodiment.

FIG. 12 is a display diagram of a conventional liquid crystal display.

[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 25 Route Search Data 26 Node Connection Data 27 Link Cost Data 28 Route Display data

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location // G06F 17/00

Claims (4)

[Claims] 1. A storage means in which road data is recorded, a current position calculation means for detecting the current position of the vehicle based on the traveling speed and traveling direction of the vehicle, and a road map read from the storage means. Display means for displaying the present position obtained by the present position calculating means, destination input means for inputting a destination, and search for a route to the destination inputted by the destination input means and display the route. Means for displaying the route, distance determining means for determining whether or not the current position obtained by the current position calculating means is within a certain distance range from the destination, and the current position is determined by the distance determining means. When it is determined that the vehicle is within a certain distance range from the destination, the name of the specific point existing within the predetermined range centering on the destination and the specific point name such as a symbol are displayed on the display means. A route search display device for collection. 2. When the distance determining means determines that the current position is within a certain distance range from the destination, the names of intersections existing within a predetermined range centered on the destination or the names of facilities, The route search display device according to claim 1, wherein a symbol is displayed. 3. A direction display means for determining a destination direction based on the current position calculated by the current position calculation means and the destination input by the destination input means, and displaying the destination direction on the display means. The route search display device according to claim 1. 4. The scale of the display map so that the vehicle position and the destination are displayed on the same screen of the display means when the distance determination means determines that the current position is within a certain distance range from the destination. 2. The route search display device according to claim 1, further comprising automatic scale switching means for automatically switching.