JPH0875490A - Route retrieving device - Google Patents

Abstract

PURPOSE: To provide a route retrieving device in which a route conforming to the actual use between a starting point and a goal point can be displayed. CONSTITUTION: Coordinate data (P1-P6) contained in a road form data are read, and segments (L1-L5) connecting them are generated. Perpendiculars 222, 212 are drawn down from a point S which is the point on the link closest to a predetermined starting point or the point on the link closest to a goal point to the generated segments, and the closest intersection (point P) is determined. An image data is generated in such a manner that, when the point S is the point on the link closest to the starting point, the segment in the direction from the point P to the terminal end is displayed, and when the point S is the point on the link closest to the goal point, the segment in the direction from the point P to the starting end is displayed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a route searching device for searching a route between a starting point and a destination, and more particularly to a route searching device for storing road map data composed of a network of links.

[0002]

2. Description of the Related Art A route search device for constructing road map data by a network of a plurality of links and searching for a route between a departure point and a destination point is used in a car navigation system or the like.

In a car navigation system, for example, the travel time for traveling each link is stored, and the GPS (Global Positionin) is stored.
g System) and various sensors set the current point, and when the destination point is input using a remote control key or the like, a route, which is a set of links with the least travel time, is searched and displayed on the screen.

[0004]

However, the conventional route searching device has a problem that the route from the current position to the destination is not accurately displayed.

FIG. 11 is a diagram for explaining a problem in the conventional route search device. In the conventional route search device, the route is displayed for each link. Therefore, since the route is displayed from the node 201a, when the current position is away from the node as shown in FIG. 11, the driver can only look at the displayed range 203 to determine which way the route should go to reach the destination. I don't know

It is also not preferable that the departure point and the destination point are separated from the end points of the route.

The present invention has been made to solve the above problems, and it is an object of the present invention to provide a route search device capable of displaying a route from the current point to the destination point according to actual use. To aim.

[0008]

A route search device according to the invention of claim 1 comprises a network of a plurality of links for road map data and searches for a route between a starting point and a destination point. A recognition means for recognizing the link closest to the starting point as a starting link, a searching means for searching a desired route from one end of the starting link and the destination point, and a link including at least one end of the starting link. Display means for displaying the portion.

The route search device according to the invention of claim 4 is
The route search device according to claim 1, further comprising: first storage means for storing shape data corresponding to each of the links by dividing the shape data into a plurality of blocks, and shape data corresponding to each of the links and the blocks. Second display means for storing the correspondence relationship with the block is provided, and the display means reads a desired block from the block based on the stored correspondence relationship and displays the shape data of the link portion.

[0010]

According to the route search device of the present invention, at least one end of the link closest to the starting point and at least one end of the link closest to the starting point that contacts the desired route are included. Display the link part.

According to the route search device of claim 4, in addition to the operation of claim 1, the shape data corresponding to each link is divided into a plurality of blocks and stored, and the shape data corresponding to each link is stored. The corresponding relationship with the existing block is stored, a desired block is read from the block based on the stored corresponding relationship, and the shape data of the link portion is displayed.

[0012]

FIG. 1 is a block diagram of a route search device in one embodiment of the present invention.

The route search device is a CP that controls each block.
U101 and a CD-ROM 103 that stores road map data configured by a network of a plurality of links,
Input device 10 consisting of remote controller, joystick, etc.
5, various sensors 107 for measuring vehicle speed, GPS
(Global Positioning System
m) G that catches radio waves from satellites and recognizes the current location
PS 109, display 111 that displays a road map including routes, and ROM that stores programs and various constants
113 and a RAM 115 for temporarily storing data.

FIG. 2 is a diagram for explaining network data of road links stored in the CD-ROM 103.

Roads are represented as a set of links 207 in the network data. The node 205 is set at an intersection or a boundary of a block of road shape data of a scale 1 described later. Corresponding to each link, a link number (#n) for recognizing the link and time data required for traveling the link are stored. The desired route is obtained from this time data. For the route calculation, for example, the potential method (Kobayashi et al. “Navigation system with recommended route display function” Sumitomo Electric No. 141,
p. 155 to 160.1 September 1992) and the like are used.

FIG. 3 is a diagram for explaining the road shape data of the scale 1 stored in the CD-ROM 103, and FIG.
FIG. 6 is a diagram for explaining road shape data of scale 2 stored in CD-ROM 103.

The road shape data is data used to display a link and includes a plurality of coordinate data for reproducing the shape of the road. The road shape data for each of the scales 1 and 2 is stored in the CD-ROM 103 in block units.

The scale 2 has a smaller scale ratio of the map than the scale 1, and includes coordinate data of a fine portion of the road. For example, the coordinate data of the road between the nodes A and B is block B1.
In the portion (FIG. 3), only the coordinate data of P1 and P2 are set at the scale 1, but the coordinate data of P10 to P14 is set more finely at the scale 2 (FIG. 4). As a result, it is possible to display a more accurate road shape at scale 2 than at scale 1.

One link is set so as not to cross the boundary of the block of reduced scale 1 like a link between nodes A and B, for example. Therefore, in order to generate the image data of one link at the scale 1, the CD-ROM 10
One block from 3 to 1 is read into the RAM 115.

On the other hand, at scale 2, one link spans a plurality of blocks, so in order to generate image data for one link at scale 2, a plurality of blocks are read from CD-ROM 103 to RAM 115. I need to put it out. For example, in order to generate the image data at the scale 2 of the link between the nodes A and B in FIG. 3, B1, B6, and B are generated.
It is necessary to read blocks 7, B8, B13, B14, B15 (also B1 for the link between nodes B and E).
0, B15, B15, B2 in the link between the nodes B and C
0). Therefore, the CD-ROM 103 stores the block number of the scale 2 including one link as a link pair block table. In the link pair block table, the block numbers are stored in order from the start end (node A) to the end (node B) of the link.

FIG. 5 is a flow chart for explaining the processing of the CPU in the route search device in one embodiment of the present invention.

This embodiment is characterized in that a start end process and a end process for generating image data of links close to the departure point and the destination point are performed based on the searched route.

In step S101, route calculation is performed by, for example, the potential method, and in step S102, route start processing at the scale 1 is performed. In step S103, the termination process at the reduced scale 1 is performed. Scale 2 in step S104
The beginning of the route is processed. Step S1
At 05, termination processing of the route at the scale 2 is performed. In step S106, the route is displayed on the map displayed on the display 111.

FIG. 6 is a flow chart for explaining the start end processing of the scale 1 in the flow chart of FIG. 5, FIG. 7 is a diagram for explaining the coordinate sequence of FIG. 6, and FIG. 8 is a flow chart of FIG. It is a figure for demonstrating a process.

The start link in the route searched in step S201 (the link closest to the departure point)
The road shape data of the block of scale 1 including
It is read from the ROM 103 to the RAM 115. In step S202, a coordinate string, which is a set of coordinate data representing the shape of the road, is created from the coordinate data included in the road shape data as shown in the table of FIG. 7 corresponding to the start link. In step S203, as shown in FIG. 8, a line segment (L which can draw a perpendicular line from the point S (point on the link closest to the starting point, which is obtained in advance) among the line segments formed by the coordinate sequence can be drawn.
The vertical lines 211 and 212 are lowered with respect to (3, L5), and the number (L3) of the closest line segment and the coordinate P of the intersection are obtained. When there are two or more intersections having the same perpendicular length, the intersection P closest to the destination is selected. In step S204, the line segment number (L3) in the RAM 115
The coordinates P and the display direction are stored. The display direction is a direction in which the link is displayed from the coordinate P, and is set so that the end direction (the direction connected to the searched route) is displayed from the coordinate P in the start end process.

In the termination process, steps S201 to S2
The processing of 03 is a termination link (link close to the destination)
In step S204, the display direction is set so that the starting end direction (direction connected to the searched route) is displayed from the coordinate P.

FIG. 9 is a flow chart for explaining the start end processing of the scale 2 in the flow chart of FIG.

In step S801, the CD-ROM
From 103, a link-to-block correspondence table in which which block of the scale 2 the start link is included is read from the RAM 115. The order i of blocks to be processed in step S802 is set to 1. In step S803, it is determined whether the shape data of all blocks have been processed. If NO, the road shape data of the i-th block is read in step S804, and step S80
In 5, the coordinate sequence corresponding to the start link is created from the coordinate data included in the road shape data. Step S80
At 6, i is incremented by 1. Step S80
If YES is obtained in step 3, in step S807, a perpendicular line is drawn from the point S to the line segment formed by the coordinate sequence, and the closest line segment and the coordinate P of the intersection are obtained. In step S808, data indicating "not displayed" is stored in the block in the starting direction from the block including the coordinate P, and data indicating "displaying all" is stored in the block in the ending direction from the block including the coordinate P. It In the block including the coordinate P, the number of the line segment including the coordinate P, the coordinate P, and the display direction are stored. The display direction is the coordinate P in the case of the start end processing.
The portion of the link extending from the coordinate P to the starting end direction is set not to be displayed so that the portion of the link extending from the end point to the end direction is displayed.

In the scale-down 2 termination process of FIG. 5, after the processes of steps S801 to 807 have been performed on the termination link, the blocks located in the direction of the start end from the block including the coordinate P in step S808 are "all The data indicating “display” is stored, and the data indicating “not displayed” is stored in the block located in the terminal direction from the block including the coordinate P. In the block including the coordinate P, the link that is directed from the coordinate P toward the start end is set to be displayed as the display direction.

Termination processing is performed so that the end of the route is closer to the destination.

FIG. 10 is a flow chart for explaining the route display processing of the flow chart of FIG.

In step S901, road shape data required for display is read in block units. Step S
At 902, it is determined whether the road shape data of all blocks have been processed. If YES in step S902, the route display ends. If NO in step S902, it is determined in step S903 whether the road shape data being processed includes a start link or an end link, and if YES, in step S904 in FIG.
Coordinates P created by the start and end processing shown in FIG.
From the display data and the display direction data, a portion displaying the route in the link and a portion not displaying the route are discriminated, and the image data corresponding thereto is displayed. If NO in step S903, all routes corresponding to the links of the block are displayed in step S905.

As described above, by using this embodiment, it is possible to display the route from the starting point to the destination point according to the actual use.

[0034]

With the route search device according to the first aspect of the present invention, the route suitable for the actual use can be displayed, and the usability is improved.

In the route search device according to the invention of claim 4, in addition to the effect of claim 1, the processing speed can be increased.

[Brief description of drawings]

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

FIG. 2 is a diagram for explaining network data of road links stored in a CD-ROM 103.

FIG. 3 is a diagram for explaining road shape data of reduced scale 1 stored in a CD-ROM 103.

FIG. 4 is a diagram for explaining road shape data of reduced scale 2 stored in a CD-ROM 103.

FIG. 5 is a view showing C in the route search device according to the embodiment of the present invention.
It is a flow chart for explaining processing of PU.

FIG. 6 is a flowchart for explaining a start end process of the scale 1 in FIG.

FIG. 7 is a diagram for explaining the coordinate sequence of FIG.

FIG. 8 is a diagram for explaining the process of FIG.

9 is a flowchart for explaining a start end process of the scale 2 in FIG.

10 is a flow chart for explaining the route display process of FIG.

FIG. 11 is a diagram for explaining a problem in a conventional route search device.

[Explanation of symbols]

 101 CPU 103 CD-ROM 105 Input Device 107 Various Sensors 109 GPS 111 Display 113 ROM 115 RAM 205 Node 207 Link

Claims (4)

[Claims] 1. A route search device configured to construct road map data by a network of a plurality of links, and to search for a route between a departure point and a destination point, wherein a link closest to the departure point is recognized as a start link. A recognition means, a search means for searching a desired route from one end of the starting end link and the destination point, and a display means for displaying a portion of the link including at least one end of the starting end link, Search device. 2. A second recognizing means for recognizing a link closest to the destination point as an end link, wherein the searching means searches for the desired route from one end of the start end link and one end of the end link. The route search device according to claim 1. 3. The route search device according to claim 2, further comprising a generation unit that generates image data corresponding to a portion of the end link that includes at least one end of the end link. 4. A first storage unit that stores shape data corresponding to each of the links by dividing the shape data into a plurality of blocks, and stores the corresponding shape data of each of the links and the blocks. A second storage unit that stores a correspondence relationship with a block, wherein the display unit reads a desired block from the block based on the stored correspondence relationship and displays shape data of the link portion. The route search device according to claim 1.