JP3341645B2 - Route guidance device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a route guidance device, and more particularly to a route guidance device for guiding a route based on map data which is a set of a plurality of nodes and links connecting the nodes.

[0002]

2. Description of the Related Art Hitherto, there has been known a navigation device (a type of route guidance device) that forms road map data by links connecting nodes and calculates a recommended route to a destination. The navigation device receives a radio wave from a GPS (Global Positioning System) satellite, confirms the current position of the vehicle, and displays a recommended route from the current position of the vehicle to the destination.

[0003] One link of road map data usually corresponds to data of one actual road. However, for example, as shown in FIG. 45, when one road is provided with a median strip M, one road is one road.
One road is a two-way road, not represented by a link.
It is represented by a book link. This is the standard method of expressing map data in the industry.

[0006] That is, the actual route shown in FIG. 45 is stored as data of the link and the node shown in FIG. The solid arrow in the figure indicates a one-way link, and the dotted arrow in the figure indicates a recommended route on which the vehicle should travel.

[0005] As shown in FIG. 47, a general road passing under the highway H is also included in the road map data.
Sometimes expressed as a book link.

[0006]

By the way, in the navigation device, there is known a technique of displaying an enlarged view of an intersection to be guided next on a screen. The driver can easily know the direction in which he should proceed by looking at the enlarged view. The data for displaying the enlarged view may be separately stored in an external storage device (CD-ROM, MD, DVD, or the like).
It is common to display an enlarged view based on road map data for display.

However, if road map data which originally represents one road by two links is used as shown in FIG. 46, an enlarged view of an intersection as shown in FIG. 48 is displayed. This is a display different from the actual intersection in FIG. 45, and will hinder route guidance.

FIG. 49 is a diagram showing an example of road map data, and FIG. 50 is an enlarged view of the vicinity of the intersection B in FIG. The road connecting intersection A and intersection B is a road separated by a median strip, and is represented as two opposing one-way links. At intersection B, the median strip is interrupted. Where the median strip is interrupted, the two opposing one-way links are connected by an intra-intersection link (specific link) IL.

When the recommended route is the route indicated by the arrow in FIG. 50 and the vehicle approaches the intersection B, the display of FIG. 51 is displayed as an enlarged view of the intersection.

[0010] However, since this is a road separated by a median strip displayed by two links, the image differs greatly from the actual route shown in FIG. 52. That is, referring to FIG. 52, although the route on which the vehicle should travel is actually a diagonally forward right direction, as shown in FIG.
After making a right turn at °, a display is displayed that requires the user to proceed to the left front. In addition, when performing guidance by voice, an unnatural guidance different from an actual intersection is performed for the user, such as "Please turn right and turn left and go forward."

Referring to FIGS. 53 and 54 (enlarged view of intersection D in FIG. 53), the recommended route of the vehicle is intersection C.
, And turn left at intersection D. At this time, the portion surrounded by the circle in FIG. 54 is displayed as an intersection enlarged view as shown in FIG. Here, the shape of the intersection shown in FIG. 55 is a crossroad,
Since the actual shape of the road is a T-shaped road as shown in FIG. 56, it may hinder driving.

Similarly, referring to FIGS. 57 and 58 (enlarged view in the circle in FIG. 57), if the recommended route of the vehicle is the route indicated by the arrow in FIG. The screen shown at 59 will be displayed. Here, according to FIG. 59, although the road (3) and the road (4) look as if they are different roads, in reality, the same direction as shown in FIG. Road, and the driver may mistake the direction in which the vehicle should travel.

In some cases, additional information for guiding a route is stored in a link. In this case, the following problem occurs.

Referring to FIG. 61, one actual intersection in the map data includes four nodes N1 to N4,
It is assumed that they are connected by the intra-intersection links IL1 to IL4. It is assumed that the links HL1 and HL2 record additional information indicating that the link is a highway link.

Here, the link to which the vehicle should travel is the link L
If the link is HL1 and the link HL1, guidance for making a right turn is performed at the node N4. Here, the nodes N1 to N4 are actually one intersection, and when instructing the driver to make a right turn, output a voice such as "Please turn right at the entrance of the expressway" based on the additional information. Is preferred.

However, since the link IL1 after making a right turn is a link within an intersection and not an expressway link, such appropriate guidance cannot be provided.

The present invention has been made to solve the above problems, and has as its object to provide easy-to-understand guidance in a route guidance device.

[0018]

According to one aspect of the present invention, a route guidance apparatus guides a route based on map data which is a set of links connecting a plurality of nodes. An apparatus, comprising: a node identifying unit that identifies a plurality of nodes included in one actual intersection from a plurality of nodes;
And the node combining means for combining as One intersection is synthesized
Display means for displaying the shape of the intersection using the selected node
And

[0019] More preferably, the node identifying means identifies a node connected by a specific link as a node included in one actual intersection.

More preferably, the node identifying means identifies two nodes connected by a link having a predetermined length or less as nodes included in an actual intersection.

[0021] More preferably, the route guidance device further includes link combining means for combining at least two links extending in the same direction from a plurality of nodes included in one actual intersection as one road.

More preferably, the node combining means of the route guidance device also combines additional information associated with the plurality of identified nodes.

According to another aspect of the present invention, a route guidance device is a route guidance device for guiding a route based on map data, which is a set of links connecting a plurality of nodes. a plurality of links extending, link identifying means for identifying a plurality of links corresponding to roads to the same direction, and the link combining means for combining a plurality of links identified as one road, which is synthesized Re
Display means for displaying the shape of the intersection using the link .

More preferably, the link combining means combines the links as one road by averaging the directions of the plurality of links identified by the link identifying means.

More preferably, the link synthesizing means includes a deleting means for deleting a desired link from a plurality of links corresponding to a road continuing in the same direction, and the deleting means means that the vehicle travels on a road corresponding to the recommended route. Remove the links other than the ones that should be, and on the roads other than the road that corresponds to the recommended route,
Delete links other than one-way links going outward from the node.

According to these inventions, the predetermined node is 1
Since the intersection is combined as one intersection or the predetermined link is combined as one road, it is possible to provide a route guidance device capable of providing easy-to-understand guidance.

If the intersection is displayed after the combination, a display close to the shape of the actual intersection can be made. Further, by using the data after the synthesis, the guidance by voice can be accurately performed. Further, the direction in which the vehicle travels can be appropriately determined.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] FIG. 1 shows a navigation device (a type of route guidance device) according to a first embodiment of the present invention.
FIG. 3 is a block diagram showing a circuit configuration of FIG.

Referring to the figure, the navigation device drives a CPU 1 for controlling the entire device, a CD-ROM 2 for storing road map data which is a set of links connecting a plurality of nodes, and the device. 3 for storing a work area or the like, a liquid crystal display 5 for displaying a recommended route superimposed on map data, and for inputting information such as a destination from an operator. A remote controller 6, a speaker 7 for outputting a direction in which the vehicle should travel by voice or the like, and a GPS
It comprises a device 8 and a gyro 9.

Next, a specific example of road map data stored in the CD-ROM 2 will be described.

FIGS. 2 to 4 show an intersection between a two-way road (a road in which the upper and lower lines are separated; the same applies hereinafter) and an ordinary road (a road capable of bidirectional traffic; the same applies hereinafter). It is a figure showing the example of road map data.

In the drawing, a one-way arrow indicates a one-way link, a two-way arrow indicates a normal road link, and a dotted line indicates a link within an intersection (which indicates that a link can be passed to an adjacent link). Link indicating a link connecting a plurality of nodes included in one actual intersection).

In the example shown in FIGS. 2 to 4, two nodes are included in one actual intersection.

FIGS. 5 and 6 are diagrams showing specific examples of map data of intersections between two-way roads and two-way roads. The central portion of the intersection is connected by an intra-intersection link indicated by a dotted line. As a result, four nodes are included in one actual intersection.

FIGS. 7 and 8 are diagrams showing examples of map data of an intersection between a three-way road (a road having three traveling lanes; the same applies hereinafter) and a two-way road.

At these intersections, six nodes are included in one actual intersection.

FIG. 9 is a diagram showing a specific example of map data of an intersection between a four-road (a road consisting of four driving lanes; the same applies hereinafter) and a two-road.

In this example, eight nodes are included in one actual intersection.

Next, a specific example of the processing performed by the navigation device according to the present embodiment will be described.

The navigation device uses the GPS device 8 to identify the current position of the vehicle. The destination is input via the remote controller 6. Based on the road map data included in the CD-ROM 2, a recommended route connecting the current position of the vehicle to the destination is calculated.

The navigation device uses the GPS device 8 and the gyro 9 to sequentially identify the current position of the vehicle. A road map centering on the identified point and a recommended route are displayed on the liquid crystal display 5. An enlarged view of the intersection is displayed immediately before the vehicle reaches the node on the recommended route where the next right / left turn is to be performed.

In the display of the enlarged view of the intersection, a plurality of nodes included in one actual intersection are identified,
The identified nodes are displayed as one intersection. Thus, a display closer to the shape of the actual intersection can be performed.

More specifically, the link type (link within the intersection or other link) of the link extending from the node determined to require a right / left turn guidance is determined. Here, if there is an intra-intersection link, it is determined that the nodes need to be combined, and the node for which the right / left turn guidance is required is set as the combination reference node.

FIG. 10 is a diagram showing a link in a state in which a two-road road intersects with a two-road road and a road extending in an oblique direction is connected to the intersection. Dotted lines indicate links within the intersection, and bold arrows indicate recommended routes. FIG.
In, the node of (1) becomes the synthesis reference node.

For example, when the recommended route is indicated by a thick arrow in FIG. 11, the node (2) is the synthesis reference node.

When nodes are combined in the state shown in FIG. 10, by following links within the intersection (links indicated by dotted lines) from the combining reference node (1), (2)
And the node of (4). Next, the node of (3) is obtained by further following the links within the intersection from the nodes of (2) and (4). Thereby, (1)-
It is identified that the node (4) is a node included in one actual intersection, and is determined to be a node to be combined. That is, as shown in FIG. 12, (1) to (4)
13 are synthesized as shown in FIG. 13 by subtracting the links within the intersection from the enlarged shape of each intersection with respect to the node of FIG. 13, so that the shape shown in FIG. 14 is created as an actual intersection enlarged shape. Become.

However, in the state shown in FIG. 14, since the crossroads continuing in the vertical and horizontal directions in the figure are each composed of two links, it is necessary to delete unnecessary links. The deletion of the link is performed as described below.

Referring to FIG. 15, if there are one-way links L1 to L8 extending from each of nodes (1) to (4) to be combined, and the recommended route is composed of links L1 and L2, FIG. As shown in the link L3,
L5, L7 and L8 are deleted. This leaves, in principle, a one-way link outward from the node. However, on the road where the vehicle goes to the node, the one-way link (L8) in the direction going out of the node is deleted, and the one-way link (L1) to the node is left. This is to perform a display closer to the shape of an actual intersection by leaving a link where the vehicle actually travels.

With the above processing, an enlarged view of a shape close to the actual intersection shown in FIG. 17 can be displayed from the road map data constituted by the connection of nodes and links shown in FIG. .

FIG. 18 and FIG. 19 are flowcharts showing the node combining process and the link deleting process in this embodiment.

Referring to the figure, in step S101, a map data pointer of a node to which the vehicle makes a right or left turn and which is to be reached next (guide node) is obtained from the calculated recommended route. Here, the map data pointer is a number for specifying a node assigned to each node. In step S102, the coordinates of the guidance node (synthesis reference node) and the map data pointer are stored in the synthesis target node table.

Here, the synthesis target node table refers to the coordinates (X,
Y) and a table for recording the position information of the nodes in the map data. In this table, node coordinates and node position information are recorded for the number of nodes to be combined.

Returning to FIG. 18, in step S103, the number of branches of the link extending from the node is obtained. Next, in step S104, the direction in which the respective branches extend is calculated.

Next, in step S105, the road type and link type of the branching node are obtained from the road map data. Here, the road type is data indicating the attribute of the road, and is, for example, a type such as a national road, a prefectural road, a city road, or a narrow street. As described above, the link type is data indicating the nature of the link, and is, for example, a type such as a link in an intersection, a normal link, or a link indicating a ramp on an expressway.

In step S106, it is determined whether or not there is a link whose link type is a link within an intersection.
If YES, in step S121, the map data pointer of the adjacent node is obtained by following the link in the intersection. This specifically corresponds to the map data pointer of the nodes (2) and (4) in FIG.

Next, in step S122, it is determined whether the node is registered in the combining target node table. If NO, the coordinates of the node and the map data pointer are stored in the compositing target node table in step S123. Thereafter, the processing from step S107 is performed.

If NO in step S106 or YES in step S122, step S1 is continued.
Proceed to 07.

In step S107, it is determined whether all the links branching from the node have been processed.
The processing from step S104 is repeated.

If "YES" in the step S107, it is determined in a step S108 whether or not a branch link has been processed for all the nodes registered in the combining target node table. If NO in step S108,
In step S109, the next node registered in the synthesis target node table is set as a processing target, and step S103 is performed.
The processing from is performed.

If YES is determined in the step S108, in a step S110, the information of all the obtained links is
Consolidate in the composite intersection shape table. Here, as shown in FIG. 21, the combined intersection shape table includes a link type of a link extending from a node to be combined, a road type, a branch angle (0 to 360 °), and a width of the road. It is composed of the traffic information and a flag indicating whether the route is an entry route or an exit route to the node on the recommended route. This table is created for each branch link.

Next, in step S111, all links having the link type within the intersection are deleted from the composite intersection shape table. This is because the links within the intersection are not displayed at all because the nodes are combined.

Next, in step S112, a search is made for a link having the same road type as a one-way link in the opposite direction to the branch links extending in the same direction from the composite intersection shape table. This is because the link is divided into upper and lower lines by a median strip or the like (for example, L in FIG. 15).
1 and L8).

In step S113, it is determined whether such a link has been searched. If YES, step S11
At 4, it is determined whether the vehicle's approach route (L1 in FIG. 15) on the recommended route is included in the two links. This determination is specifically made based on the entry road / exit road flag of the composite node shape table shown in FIG.

If "NO" in the step S114, the road (for example, L8 in FIG. 15) on the side other than the approach road of the vehicle is deleted from the composite intersection shape table in a step S124. Thereafter, the processing from step S116 is performed.

On the other hand, if NO in step S114,
In step S115, the road on the side toward the node (for example, L3, L5, L7 in FIG. 15) is deleted from the composite intersection shape table, and the process proceeds to step S116.

In step S116, it is determined whether or not all links forming a pair which are considered to be divided into upper and lower lines by a median strip or the like have been searched. If NO, the process from step S112 is repeated. Execute.

If YES in step S116, a combined intersection shape (FIG. 17) is created based on the information in the remaining combined intersection shape table in step S117. In step S118, based on the route calculation result,
The link to which the vehicle should travel among the links at the synthesized intersection is determined. Next, in step S119, the synthesized intersection shape and the direction in which the vehicle should travel are displayed on the liquid crystal display 5.

Next, effects of the present embodiment will be described. For example, it is assumed that the recommended route is a route that goes obliquely after passing through the intra-intersection link IL shown in FIG. At this time, referring to FIG. 22, node N1 becomes the synthesis reference node. Then, by following the link IL within the intersection from the combining reference node N1, a node N2 to be combined is obtained. Then, the link connected from each of the nodes N1 and N2 is identified, and the link indicated by the thin line shown in FIG. 22 is deleted from the composite intersection shape table. As a result, only the link indicated by the thick line in FIG. 22 is displayed.

Thus, when the vehicle approaches the node N1, the liquid crystal display 5 displays the synthesized intersection shape shown in FIG. This is Figure 5
The shape is very close to the shape of the actual intersection shown in FIG. 2, and the user can easily grasp the direction in which the vehicle should travel.

The link included in the recommended route is shown in FIG.
24, the node N1 and the node N2 are combined with each other with reference to FIG. 24, and the link indicated by the thin line is deleted. This allows
The road shape shown in FIG. 25 is displayed on the liquid crystal display 5. This is very close to the actual road shape shown in FIG.

Similarly, it is assumed that the road map data composed of a set of nodes and links stored in the CD-ROM 2 is as shown in FIG. FIG.
It is an enlarged view of the part enclosed by the circle. In FIG. 27, a recommended route is indicated by a thick arrow.

At this time, referring to FIG. 28, the combining reference node is N1, and it is identified that the nodes to be combined are N2 to N6. Then, by deleting the link indicated by the thin line, the display shown in FIG. 29 is made as an enlarged view of the intersection.

As described above, in the present embodiment, the nodes included in one actual intersection are combined, and after the links other than the links suitable for the traveling of the vehicle are deleted,
The enlarged display of the intersection is performed. As a result, a more accurate intersection shape can be displayed, and guidance that is easy for the user to understand can be provided in the navigation device.

Further, referring to FIG. 30, when the intra-intersection link IL1 is inclined with respect to the link L1,
When the traveling direction of the vehicle is the links L1 and L2, the vehicle need only travel straight ahead, and route guidance is essentially unnecessary. However, in the related art, the node N1 may be informed that the vehicle should go forward diagonally right.

On the other hand, in the present embodiment, as shown in FIG. 31, since the guidance is performed after the nodes are combined, it is easily determined that the guidance is unnecessary because the route is straight. can do.

Also, when guidance is provided by voice after the synthesis is performed, guidance can be appropriately provided.

Referring further to FIG. 32, nodes N1 to N
4 as landmark information M1 as additional information.
It is assumed that M4 is stored. Here, the landmark information M1 to M4 are a post office, a convenience store, a gas station, and a bank, respectively.

When the nodes N1 to N4 are combined with the landmark information, the shape of the intersection shown in FIG. 33 can be obtained, and guidance can be performed with data close to the actual intersection. .

On the other hand, in the conventional technique, only one node (for example, N3) and one landmark information (for example, M3) are to be guided, so that all landmarks recorded as data are displayed. Can not do.

Referring further to FIG. 34, when destination information of Tokyo, Osaka, Kyoto and Kobe is recorded as additional information in each of the links extending from the node,
By combining these pieces of additional information, data of the intersection shown in FIG. 35 can be obtained, and appropriate guidance can be provided.

Further, when the vehicle is approaching the intersection shown in FIG. 61 and the guidance is performed after combining the nodes N1 to N4, it is turned right based on the additional information of the link HL1 to enter the entrance of the expressway. Can be notified to the driver.

[Modification] In the above-described first embodiment, all links in the intersection are deleted and the nodes are combined with each other. Without deleting the link, the intersection is enlarged and displayed while leaving the link in the intersection.

(1) When the recommended route is a U-turn route. That is, when the recommended route calculated with reference to FIG. 36 is a U-turn route via a link IL within an intersection indicated by a dotted line. Does not delete the intra-intersection link IL indicated by the dotted line. Thereby, the intersection enlarged display becomes a display as shown in FIG. Thereby, the user can easily know that the recommended route is the U-turn route.

(2) When the recommended route includes a lane change route. That is, referring to FIG. 38, when the recommended route indicated by an arrow is a route that changes lanes via link L2 within an intersection Does not delete the link L2 where the vehicle travels among the links within the intersection, but only deletes the link L1 within the intersection where the vehicle does not travel. Thereby, the intersection enlarged display becomes a display as shown in FIG. 39, and the user can easily know that the lane should be changed.

[Second Embodiment] The hardware configuration of the navigation device according to the second embodiment is the same as that of the first embodiment, and the description thereof will not be repeated. The shapes of links to be combined in the second embodiment are shown in FIGS. That is, referring to FIG. 40, link L1 indicating a normal road
Are connected to a V-shaped link L2, L3 via a node N. The links L2 and L3 are links extending in the same direction from the node N, and are one-way links in opposite directions. That is, the links L2 and L3 are links indicating one road divided by a median strip or the like.

In the example of FIG. 41, links L4 and L5 indicate one road separated by a median strip or the like, and similarly, links L6 and L7 indicate one road. Each road is connected by a node N.

In the example of FIG. 42, links L8 and L9 indicating one road are added to the node N
Connected by

The present embodiment is characterized in that the shape of the intersection is displayed by combining the two links connected in such a V-shape. At this time, in the synthesis, an average of the directions of the pair of links La and Lb connected by the node N is calculated with reference to FIG. 43, and the link Lc is displayed.

FIG. 44 is a flowchart showing a process for displaying an enlarged view of an intersection in the present embodiment.

Referring to the figure, in step S201, based on the recommended route, a node (guide node) through which the vehicle next passes
Is obtained. Step S202
Then, the direction of each of the links extending from the guide node is calculated. In step S203, information on all links is registered in the composite intersection shape table. The composite intersection shape table is the same table as the table shown in FIG.

In step S204, it is determined whether all the links have been processed.
Is repeated.

If YES in step S204, in step S205, the links which are directed in the same direction from the composite intersection shape table and indicate one-way traffic in the opposite directions, and have the same road type. Search for. If it is determined in step S206 that such a link has been found, it is a link indicating an originally one road which is separated into a vertical line by a median strip or the like, and the combining process is performed from step S207.

In step S207, the average of the angles in the directions of the two links forming a pair is calculated as shown in FIG.

In step S208, it is determined whether or not the two links include the approach road of the vehicle. If YES, the link on the side other than the approach road of the vehicle is deleted from the intersection shape table in step S215.

On the other hand, if NO in step S208,
In step S209, the link entering the intersection is deleted from the intersection shape table.

Next, the direction of the link not deleted in step S210 is replaced with the angle obtained in step S207.

At step S211, it is determined whether all pairs of links have been searched, and the processing from step S205 is repeated until the result of determination is YES.

At step S212, an intersection shape is created from the remaining link shapes in the intersection shape table.
From the recommended route calculated in step S213, it is determined to which link the road on which the vehicle should exit the intersection belongs.

Then, in step S214, the shape of the intersection and the recommended route are displayed. That is, by the processing in this flowchart, the links La and Lb which are actually one road but are recorded as a pair of links as road map data as one road Lc as shown in FIG. Is displayed. Thereby, in reality, FIG.
Although the intersection is as shown in FIG.
It is prevented that the shape of the intersection where the road continues in a V-shape as shown in FIG.

By executing both the processing in the flowcharts shown in FIGS. 18 and 19 and the processing in the flowchart shown in FIG. 44, the combining processing of the nodes connected by the links within the intersection and the V-shaped The combining process of the link extending in the shape may be performed by one navigation device.

In the first embodiment, a node connected by an intra-intersection link (specific link) is determined to be a node included in one actual intersection.
Two nodes connected by a link having a predetermined length (for example, a real length of 30 m) or less may be determined to be a node included in one real intersection.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a circuit configuration of a navigation device according to a first embodiment of the present invention.

FIG. 2 is a first diagram showing link data of an intersection between a two-way road and a normal road.

FIG. 3 is a second diagram illustrating link data of an intersection between a two-way road and a normal road.

FIG. 4 is a third diagram showing link data of an intersection between a two-road and a normal road.

FIG. 5 is a first diagram showing link data of an intersection between two roads and two roads;

FIG. 6 is a second diagram showing link data of an intersection between two roads and two roads;

FIG. 7 is a first diagram showing link data of an intersection between a three-road and a two-road.

FIG. 8 is a second diagram showing link data of an intersection between a three-road and a two-road.

FIG. 9 is a diagram showing link data of an intersection between a four-road and a two-road.

FIG. 10 is a first diagram for explaining node combination;

FIG. 11 is a second diagram for explaining node combination;

FIG. 12 is a diagram for explaining nodes to be combined;

FIG. 13 is a diagram for explaining a state in which nodes are combined.

FIG. 14 is a diagram showing a state where the nodes of FIG. 10 are combined;

FIG. 15 is a diagram showing a relationship between nodes and links in the data of FIG. 10;

FIG. 16 is a diagram illustrating a state in which unnecessary links have been deleted from the state in FIG. 15;

FIG. 17 shows nodes (1) to (4) in the state of FIG.
It is a figure which shows the state which was synthesized.

FIG. 18 is a flowchart illustrating a process according to the first embodiment.

FIG. 19 is a flowchart following FIG. 18;

FIG. 20 is a diagram illustrating a synthesis target node table.

FIG. 21 is a diagram showing a composite intersection shape table.

FIG. 22 is a first diagram for explaining nodes to be combined;

FIG. 23 is a diagram showing an intersection displayed after the combination is performed in the state of FIG. 22;

FIG. 24 is a second diagram illustrating nodes to be combined;

FIG. 25 is a diagram showing intersections displayed after the combination is performed in the state of FIG. 24;

FIG. 26 is a third diagram illustrating nodes to be combined;

FIG. 27 is an enlarged view of a portion surrounded by a circle in FIG. 26;

FIG. 28 is a diagram for explaining a link deleted in the state of FIG. 27;

29 is a diagram showing an intersection displayed after the combination is performed in the state of FIG. 28.

FIG. 30 is a diagram for explaining the effect of the present invention.

FIG. 31 is a diagram for explaining a state after node combination has been performed from the state of FIG. 30;

FIG. 32 is a diagram showing nodes and their additional information.

FIG. 33 is a diagram illustrating a state after the combination is performed from the state of FIG. 32;

FIG. 34 is a diagram showing a state in which additional information is recorded on a link extending from a node.

FIG. 35 is a diagram showing a state in which synthesis has been performed from the state of FIG. 34;

FIG. 36 is a diagram showing a recommended route of a U-turn.

FIG. 37 is a diagram showing an intersection displayed in the state of FIG. 36;

FIG. 38 is a diagram showing a recommended route for changing lanes.

39 is a diagram showing an intersection displayed after the combination is performed in the state of FIG. 38.

FIG. 40 is a first diagram showing link data of an intersection between a normal road and a V-shaped road.

FIG. 41 is a diagram showing link data of an intersection between a V-shaped road and a V-shaped road.

FIG. 42 is a second diagram illustrating link data of an intersection between a normal road and a V-shaped road.

FIG. 43 is a diagram for describing processing in the second embodiment.

FIG. 44 is a flowchart showing a process according to the second embodiment.

FIG. 45 is a first diagram showing an actual intersection.

FIG. 46 is a diagram showing link data corresponding to FIG. 45;

FIG. 47 is a diagram showing a link between an expressway H and a road passing under the expressway H.

FIG. 48 is a diagram showing a state where an intersection is displayed based on the data of FIG. 46;

FIG. 49 is a first diagram illustrating an example of map data.

50 is an enlarged view of a portion surrounded by a circle in FIG. 49.

FIG. 51 is a diagram showing a state where an intersection is displayed in the state of FIG. 50;

FIG. 52 is a diagram showing a shape of an actual intersection in the state of FIG. 51;

FIG. 53 is a second diagram illustrating an example of map data.

FIG. 54 is an enlarged view of a portion surrounded by a circle in FIG. 53.

FIG. 55 is a diagram showing a state in which the intersection is enlarged and displayed in the state of FIG. 54;

FIG. 56 is a diagram showing a shape of an actual intersection in FIG. 55;

FIG. 57 is a third diagram illustrating an example of map data.

58 is an enlarged view of a portion surrounded by a circle in FIG. 57.

59 is a diagram showing a state where an enlarged display of an intersection has been performed in the state of FIG. 58;

FIG. 60 is a diagram showing a shape of an actual intersection corresponding to the display of FIG. 59;

FIG. 61 is a diagram for explaining a problem of the related art.

[Explanation of symbols]

 1 CPU 2 CD-ROM 5 Liquid crystal display (display device)

Claims (8)

(57) [Claims] 1. A route guidance apparatus for guiding a route based on map data, which is a set of links connecting a plurality of nodes, includes a plurality of nodes included in an actual intersection from the plurality of nodes. display the node identifying means for identifying, and combining nodes combining means the identified plurality of nodes as one intersection, the shape of the intersection by using the combined node to node
A route guidance device comprising: 2. The route guidance device according to claim 1, wherein the node identification unit identifies a node connected by a specific link as a node included in one actual intersection. 3. The route guidance apparatus according to claim 1, wherein the node identification unit identifies two nodes connected by a link having a predetermined length or less as nodes included in one actual intersection. . 4. The apparatus according to claim 1, further comprising link combining means for combining at least two links extending in the same direction from a plurality of nodes included in said one actual intersection as one road. The route guidance device according to any one of the above. 5. The route guidance apparatus according to claim 1, wherein said node combining means also combines additional information associated with said plurality of identified nodes. 6. A route guidance apparatus for guiding a route based on map data, which is a set of links connecting a plurality of nodes, comprising: a plurality of links extending from one of the nodes; link identifying means for identifying a plurality of links corresponding to roads to the same direction, and the synthetic linking combining means the identified plurality of the link as one road, shape of the intersection by using the combined link Show
A route guidance device comprising: 7. The route guidance device according to claim 6, wherein the link combining unit combines the links as one road by averaging the directions of the plurality of links identified by the link identifying unit. 8. The link synthesizing unit includes a deletion unit that deletes a desired link from a plurality of links corresponding to the road that continues in the same direction. The route guidance device according to claim 6, wherein a link other than a link to be advanced is deleted, and a link other than a one-way link in a direction going outward from the node is deleted on a road other than a road corresponding to the recommended route.