JP2006266739A - Route guide apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform proper guide at a rotary, while reducing a processing load in a control part. <P>SOLUTION: Map data have dummy links D1-D4 for connecting the center of a rotary R to each end of connection road links La, Lb, Lc, Ld linked to rotary links R1-R6 relative to the rotary R. When the rotary R becomes a guide object spot, the first dummy link linked to a connection road link corresponding to a guide route for entering the rotary R and the second dummy link linked to a connection road link corresponding to a guide route for retreating from the rotary are specified, and a direction to be taken by a vehicle at the rotary is guided based on the angle difference between the first and second dummy links. Hereby, direction guide at the rotary R can be performed only based on the angle difference between two dummy links, to thereby enable proper direction guide, while reducing the processing load. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a route guidance device that provides guidance so that a vehicle can travel along a guidance route to a destination, and more particularly, to a route guidance device that enables appropriate guidance in a rotary.

  For the purpose of providing easy-to-understand direction guidance in a rotary, for example, an apparatus shown in Patent Document 1 has been proposed. In this conventional apparatus, first, straight traveling determination is performed based on the angle difference between the road entering and exiting the roundabout and the angle of the attachment position. For example, when the difference in angle between the incoming road and the outgoing road is within 30 °, the traveling direction in the roundabout is determined to be straight and guidance is given straight ahead. Furthermore, even if the angle difference between the entering road and the exiting road is greater than 30 °, the angle difference is 45 ° or less, and if the angle of the attachment position between the entering road and the exiting road is within 30 °, go straight And go straight ahead.

  Further, the angle difference between the entering road and the exiting road is 150 ° or more and 210 ° or less, the names thereof are equal, and the connecting road connected to the entering road and the exiting road is a face-to-face road with the same road number, Furthermore, if all the judgments that the entering and exiting roads are one-way streets and are adjacent to each other are made, the vehicle will make a U-turn at the roundabout through the one-way street. Considering a one-way U-turn guide. That is, in this case, the vehicle enters the roundabout from the connecting road through the entering road, which is a one-way road, goes around the roundabout, passes through the exit road, which is a one-way road, and then connects again. Will return to the road.

Further, the angular displacement including the rotary link from the entering road to the exiting road is obtained by integrating the clockwise angle as negative and the counterclockwise angle as positive. In the case of −180 ° <angular displacement <−150 °, the direction returns to the right, in the case of −150 ° <angular displacement <0 °, the right turn, in the case of 0 ° <angular displacement <150 °, the left turn, When 150 ° <angular displacement <180 °, it is determined that the direction returns to the left and guidance in the left-right direction is performed.
JP-A-11-51684

  As described above, in the conventional apparatus described in Patent Document 1, in order to perform straight-ahead guidance, one-way U-turn guidance, left-right guidance, etc., a link in the rotary, a road entering the rotary, a road exiting the rotary, It is also necessary to determine the angle and position of the connecting road connected to the entering road and the exiting road, the road number, the one-way road or the two-way road, and the like. That is, in order to guide the direction in which the vehicle in the rotary should travel, a very complicated calculation process has been required.

  The present invention has been made in view of the above-described points, and an object thereof is to provide a route guidance device capable of appropriately performing guidance in a rotary while reducing the processing load in a control unit.

In order to achieve the above object, a route guidance device according to claim 1 is provided.
Current position detecting means for detecting the current position of the vehicle;
Map storage means for storing road map data indicating a road by a plurality of links;
Guide route setting means for setting a guide route to reach the destination based on the road map data;
Guiding means for guiding the direction in which the vehicle should travel at the guidance target point when the current position of the vehicle approaches the guidance target point on the guidance route so that the vehicle travels along the guidance route set by the guidance route setting means. A route guidance device comprising:
The road map data stored by the map storage means has a dummy link that connects the end of the connecting road link connected to the rotary link to which the attribute of being a rotary is attached and the center of the rotary,
When the roundabout where the dummy link is set becomes the guidance target point, the guidance means includes a first dummy link connected to the connection road link corresponding to the guidance route for entering the roundabout, and guidance for leaving the roundabout. A second dummy link connected to the connecting road link corresponding to the route is specified, and a direction in which the vehicle in the rotary should travel is guided based on an angle difference between the first and second dummy links. .

  As described above, the road map data in the route guidance device according to claim 1 has a dummy link that connects the end of the connection road link connected to the rotary link and the center of the rotary link. When the vehicle approaches the roundabout as a guidance target point, it corresponds to the first dummy link connected to the connection road link corresponding to the guidance route for entering the roundabout and the guidance route for leaving the roundabout. The direction in which the vehicle should travel is guided based on the angle difference from the second dummy link that is connected to the connecting road link.

  That is, by providing the dummy link, the direction guidance in the rotary can be performed based on the angular difference between the two links just like the direction guidance at the normal intersection. Therefore, it is possible to appropriately perform guidance in the rotary while reducing the processing load.

  Here, when the diameter of the roundabout is large or the road is wide, the vehicle does not enter or leave the roundabout at right angles from the connecting road link, but between the connecting road link and the roundabout. May travel diagonally. For this reason, when a connection road link is connected at right angles to a rotary indicated by a plurality of links, the position of the vehicle may deviate from the link, and the location accuracy of the vehicle may decrease. For this reason, an approach communication link and an exit contact link may be added to the connection road link to the rotary so as to correspond to the position where the vehicle actually travels.

  In addition, as described in Patent Document 1 described above, in consideration of ease of entry / exit to / from the rotary, etc., one-way entry communication is actually made between the rotary and the connecting road connected to the rotary. Roads and exit connection roads may be provided. Even in such a case, an entry contact link and an exit contact link are interposed between the rotary link and the connection road link.

  FIG. 4 shows an example of the incoming contact links La1, Ld1 and the outgoing contact links La2, Ld2. These correspond to roads entering the roundabout R and roads exiting from the roundabout R, but as shown in FIG. 4, the entry communication links La1, Ld1 and the exit communication links La2, Ld2 are connected road links La, Ld. Is set to a different orientation. For this reason, if the direction in which the vehicle in the rotary R should go is guided based on the direction of the entry communication links La1 and Ld1 and the exit communication links La2 and Ld2, a direction considerably different from the sense of the driver of the vehicle is guided. there is a possibility.

  For example, in FIG. 4, it is assumed that the vehicle enters the rotary R from the connection road link La, travels counterclockwise on the links R1, R2, and R3 of the rotary R and then heads to the connection road link Ld. In this case, if the approach communication link La1 added to the connection road link La is a road entering the rotary R, and the exit communication link Ld2 added to the connection road link Ld is a road exiting the rotary R, the angle difference between the two roads. Therefore, guidance in the left-right direction with the direction of returning to the left is performed. However, in this case, since the driver has traveled on the connecting road link La, the left-right direction guidance for turning left at the rotary R is the guidance that matches the sense.

  Therefore, in the route guidance device according to claim 2, the dummy link is a rotary that has a direction different from that of the connection road link between at least the rotary link and at least one connection road link connected to the rotary link. With regard to connecting road links with entry communication links and exit communication links provided for entrance links and exit link links for exit from rotary links. It is characterized in that it is set so as to connect the end portion of the connecting road link and the center of the rotary link, excluding the approach communication link and the exit communication link.

  In this way, if the dummy link is set so as to connect the end of the connecting road link and the center of the roundabout while ignoring the incoming contact link and the outgoing contact link, the angles of the incoming contact link and the outgoing contact link are not considered. Therefore, it is possible to provide easy-to-understand direction guidance that matches the driver's feeling.

According to a third aspect of the present invention, the route guidance display device further includes a display device and display control means for causing the display device to display a road map including the guidance route based on the road map data.
The display control means preferably displays a road map using a plurality of links indicating roads, excluding dummy links.

  As a result, while the road map data has dummy links, only the road map that matches the actual road shape can be displayed as the road map, thereby preventing the visibility of the display map from being impaired.

  According to a fourth aspect of the present invention, it is preferable that the guidance means guides the direction in which the vehicle should travel at the guidance target point by voice. This is because by performing direction guidance using voice, the driver can recognize the direction in which the vehicle should travel while keeping his line of sight in front of the vehicle, and can contribute to safe driving of the vehicle.

  As described in claim 5, the road map data preferably has dummy links for all the rotary links included in the road map data. This makes it possible to share part of the processing for guiding the direction in which the vehicle should travel at the roundabout and the normal intersection.

  FIG. 1 is a block diagram showing an overall configuration of a vehicle navigation apparatus 20 including a route guidance apparatus according to an embodiment of the present invention. As shown in the figure, the vehicle navigation device 20 includes a position detector 1, a map data input device 6, an operation switch group 7, an external memory 9, a display device 10, a VICS transceiver 11, a voice controller 12, and a remote control sensor 16. , And a navigation ECU 8 as a control circuit connected thereto.

  The navigation ECU 8 is configured as a normal computer, and includes a well-known CPU, ROM, RAM, I / O, and a bus line for connecting these configurations. In the ROM, a program to be executed by the navigation ECU 8 is written, and a CPU or the like executes predetermined arithmetic processing according to this program.

  The position detector 1 includes a well-known geomagnetic sensor 2, a gyroscope 3, a vehicle speed (distance) sensor 4 for calculating a travel distance, and a GPS (Global Positioning) that detects the position of the vehicle based on radio waves from a satellite. System) GPS receiver 5 is included. Since these have errors of different properties, they are configured to be used while being complemented by a plurality of sensors. Depending on the accuracy of each sensor, the position detector 1 may be configured as a part of the above.

  The map data input device 6 receives map data necessary for drawing a map, including road data including node data and link data, background data indicating terrain, character data for displaying place names, and the like. It is a device to input to. The map data input device 6 includes a storage medium for storing map data. As the storage medium, a CD-ROM, a DVD-ROM or the like is generally used depending on the amount of data to be stored. A rewritable medium such as a hard disk may be used.

  Here, the configuration of node data and link data in the road data will be described. The node data includes a node ID with a unique number for each node where a plurality of roads intersect, merge, and branch, a node coordinate, a node name, a connection link ID in which the link IDs of all links connected to the node are described, It consists of various data such as intersection type, presence / absence of traffic lights, and regulation information.

  On the other hand, link data includes a link ID with a unique number for each road, link length, start and end node coordinates, road type (highway, toll road, national road, prefectural road, narrow street, road in rotary, rotary connection Road), road width, number of lanes, link travel time, legal speed limit, and other data. That is, the link of the link data is obtained by dividing each road on the map into a plurality of nodes by nodes indicating intersections, branching points, etc., and defining two nodes as links. Therefore, the node coordinates of the start point and the end point become the coordinates of the start end and end of the link.

  With these node data and link data, it is possible to draw a road on a map or calculate a guide route from a departure point to a destination by using a known method such as the Dijkstra method.

  Further, in the present embodiment, the end of the connecting road link and the center of the rotary correspond to the rotary, in particular, the rotary in which the entrance communication link and the exit communication link are provided between the rotary link and the connection road link. , And is stored in the storage medium of the map data input device 6. This dummy link is not used for displaying the road map, but only for voice guidance of the direction in which the vehicle in the rotary should travel.

  Here, the approach contact link and the exit contact link described above will be described with reference to FIG. When the diameter of the roundabout R is large or the road width of the connecting road or the roundabout R is wide, the vehicle does not enter the rotary R at a right angle from the connecting road or exit from the roundabout R. There is a case where the vehicle travels diagonally between the rotary R. For this reason, if connecting road links La and Ld are connected at right angles to the rotary R indicated by the plurality of links R1 to R6, the position of the vehicle may deviate from the links La and Ld, and the vehicle location accuracy may decrease. . For this reason, the entry communication links La1, Ld1 and the exit communication links La2, Ld2 may be added to the connection road links La, Ld to the rotary link so as to correspond to the position where the vehicle actually travels.

  In consideration of the ease of entry / exit to / from Rotary R, there are actually one-way entry and exit contact roads between Rotary R and the connecting roads connected to Rotary R. There is. Even in such a case, the entry communication links La1, Ld1 and the exit communication links La2, Ld2 are interposed between the rotary links R1 to R6 and the connection road links La, Ld.

  In the example shown in FIG. 4, since the vehicle is assumed to travel in the counterclockwise direction on the rotary R, the approach communication links La1 and Ld1 are provided on the right side of the connection road links La and Ld toward the rotary. On the left side, exit contact links La2 and Ld2 are provided.

  In FIG. 4, regarding the connection road links La and Ld having the entry communication links La1 and Ld1 and the exit contact links La2 and Ld2, the dummy links D1 and D4 are connected to the entrance contact links La1 and Ld1 and the exit contact links La2 and Ld2. It is set so as to connect the rotary side end portions of the connection road links La and Ld and the center of the rotary R by excluding them. For the connection road links Lb and Lc that do not have the entry communication link and the exit communication link, the dummy links D2 and D3 connect the connection position of the connection road links Lb and Lc to the rotary R and the center of the rotary R. Is set to The center of the rotary R does not need to be set strictly, and may be set at least at a position belonging to the rotary R according to the shape of the rotary R and the number of connecting roads.

  Further, the dummy links D1 to D4 are stored in association with identification information for specifying the rotary R or corresponding connection road links, and a desired dummy link can be read from these information.

  The operation switch group 7 is configured as, for example, a touch switch or a mechanical switch integrated with a display device 10 described later, and is used for various inputs.

  The external memory 9 has a readable / writable storage medium such as a memory card or a hard disk drive (HDD), and is used for storing various data such as text data and image data.

  The display device 10 is configured by, for example, a liquid crystal display, and a vehicle position mark corresponding to the current position of the vehicle input from the position detector 1, for example, is displayed on the screen of the display device 10 by the processing of the navigation ECU 8. A road map around the vehicle generated by the map data input from the data input device 6 is displayed.

  The VICS transceiver 11 is a device that receives road traffic information distributed from the VICS center via beacons laid on the road and FM broadcast stations in various places, and transmits necessary information to the beacons. The received road traffic information is processed by the navigation ECU 8, and for example, traffic jam information and regulation information are displayed superimposed on the road map.

  The voice controller 12 is connected to the voice recognition device 14. The voice signal input from the microphone 15 is recognized by the voice recognition device 14, and the operation information corresponding to the voice signal is navigated by acquiring the recognition information. Output to ECU8. In addition, the voice controller 12 outputs the synthesized voice and the audible sound, which are instructed by the navigation ECU 8, for guiding the direction in which the vehicle should travel to the speaker 13.

  The remote control sensor 16 wirelessly receives an operation signal from a remote control terminal (hereinafter referred to as a remote control) 17. The remote controller 17 is also used for various inputs in the same manner as the operation switch group 7 described above. For example, the navigation device 20 of this embodiment has a route guidance function, and when a destination is input by the operation switch group 7 or the remote controller 17, from the current position (or the departure point designated by the user) to the destination. The optimum route is automatically searched to calculate a guide route, and route guidance processing is performed according to the guide route. At the time of this route guidance, when the road map with the guidance route highlighted is displayed on the screen of the display device 10 or when the vehicle approaches a guidance target point such as an intersection or a roundabout, an enlarged guide map of the guidance target point is displayed. Display or guide the direction in which the vehicle should travel by voice.

  Next, a main routine executed by the vehicle navigation device 20 for map display and the like will be described with reference to the flowchart of FIG. If it is determined in this main routine that the destination has been set, route guidance processing is executed.

  In FIG. 2, first, in step S <b> 10, the current position of the vehicle is calculated based on the position data measured by each sensor of the position detector 1. At this time, the position data by the GPS receiver 5 is acquired in the same form as the coordinate data (latitude and longitude) of the road data described above. Further, the geomagnetic sensor 2, the gyroscope 3, and the vehicle speed sensor 4 acquire data related to the traveling direction and travel distance of the host vehicle, and calculate the coordinate data of the current position based on the vehicle position calculated or determined in the past. (Coordinate data calculation by self-contained navigation)

  The current position is basically obtained based on coordinate data calculated by self-contained navigation. However, when the position data by the GPS receiver 5 is acquired, the two are compared, and when the difference is not less than a predetermined distance, the position data by the GPS receiver 5 is adopted as the current position.

  Subsequently, in step S20, map data around the vehicle is read based on the coordinates of the current position of the vehicle calculated in step S10. In step S30, the vehicle mark indicating the current position of the vehicle and the read surrounding map are displayed on the display device 10. At this time, the vehicle position is specified on the road by the map matching process, and the own vehicle mark is displayed so as to correspond to the specified vehicle position.

  In step S40, it is determined whether the destination has been set using the operation switch group 7, the remote controller 17, or the like. In this determination process, if it is determined that the destination is not set, the process returns to step S10. If it is determined that the destination is set, the process proceeds to step S50.

  In step S50, an optimum route from the current position or the starting point designated by the user to the destination is searched based on the road data using a known Dijkstra method or the like. When execution of route guidance according to the searched guidance route is instructed by the user, the process proceeds to step S60 to perform route guidance processing.

  This route guidance process will be described based on the flowchart of FIG. First, the current position of the vehicle is detected in step S110, and map data around the current position of the vehicle is read in step S120. In step S130, the vehicle mark indicating the current position of the vehicle and the surrounding map are displayed, and the road corresponding to the guide route is highlighted and displayed.

  Next, in step S140, it is determined whether or not the vehicle has reached the destination. In this determination process, if it is determined that the destination has been reached, the route guidance process shown in FIG. 3 is terminated. On the other hand, if it is determined that the destination has not been reached, the process proceeds to step S150. In step S150, it is determined whether or not the vehicle has approached a predetermined distance from a guidance target point such as an intersection or a rotary. In this determination process, if it is determined that the vehicle is not approaching the guidance target point, the process returns to step S110. If it is determined that the guidance target point is approached, the process proceeds to step S160.

  In step S160, it is determined whether or not the guidance target point is a rotary. For example, when the road type of the road on which the vehicle travels is a rotary connection road, it can be determined that the guidance target is a rotary. Alternatively, in the link data constituting the guidance route, when the road type of the link located ahead of the current position of the vehicle by a predetermined distance is a road within a rotary (rotary link), it may be determined that the guidance target is a rotary. . In addition, it is possible to determine that the guidance target point is a rotary on the basis of the presence of node data of a type indicating a branch to the rotary in the guidance route.

  If it is determined in step S160 that the guidance target point is not a rotary, the process proceeds to step S170, and if it is determined to be a rotary, the process proceeds to step S180. In step S170, at a guidance target point other than the roundabout such as an intersection, an approach link entering the guidance target point and a leaving link leaving the guidance target point are read. On the other hand, in step S180, the first dummy link connected to the entrance link to the rotary and the second dummy link connected to the exit link from the rotary are read out.

  In step S190, the angle difference between the approach link and the exit link read in step S170 or the angle difference between the first dummy link and the second dummy link read in step S180 is calculated. In step S200, the direction corresponding to the angle difference is notified by voice, and an enlarged view of the guidance target point is displayed on the display device 10 to guide the direction in which the vehicle should travel.

  The merit of the direction guidance process in the route guidance process described above, particularly in the rotary, will be described with reference to FIG.

  As described above, in the present embodiment, the map data includes dummy links D1 to D4 that connect the end portions of the connection road links La to Ld connected to the rotary links R1 to R6 and the centers of the rotary links R1 to R6. Then, when the vehicle approaches the roundabout R as the guidance target point, the first dummy link connected to the connecting road link corresponding to the guidance route for entering the roundabout R, and the guidance route for leaving the roundabout The direction in which the vehicle is to travel is guided based on the angle difference from the second dummy link that is connected to the connection road link corresponding to. For example, when the approach route is the connection road link La and the exit route is the connection road link Ld, the first dummy link is D1 and the second dummy link is D4. In this case, since the angle difference between the dummy link D1 and the dummy link D4 is about 90 degrees in the clockwise direction, the vehicle traveling direction is guided to the left turn direction.

  As described above, by providing the dummy links D1 to D4, the direction guidance in the rotary R can be performed simply based on the angular difference between the two links, similarly to the direction guidance at the normal intersection. Therefore, it is possible to appropriately perform direction guidance in the rotary R while reducing the processing load on the ECU 8.

  Further, in the present embodiment, when the dummy links D1 to D4 are provided, if the incoming contact links La1, Ld1 and the outgoing contact links La2, Ld2 are interposed between the rotary R and the connecting road links La, Ld, The dummy links La and Ld are set so as to connect the rotary side ends of the connection road links La and Ld and the center of the rotary R, ignoring the entry communication links La1 and Ld1 and the exit communication links La2 and Ld2. As a result, the angle of the incoming contact link and the outgoing contact link is not considered in the direction guidance of the rotary, so that it is possible to provide easy-to-understand direction guidance that matches the driver's feeling. The reason will be described in detail below.

  As shown in FIG. 4, the incoming contact links La1 and Ld1 and the outgoing contact links La2 and Ld2 are set in a different direction from the connection road links La and Ld. For this reason, when the direction of the vehicle in the rotary R is guided based on the directions of the entry communication links La1, Ld1 and the exit communication links La2, Ld2, a direction considerably different from the sense of the driver of the vehicle is guided. There is a possibility.

  For example, in FIG. 4, it is assumed that the vehicle enters the rotary R from the connection road link La, travels counterclockwise on the links R1, R2, and R3 of the rotary R and then heads to the connection road link Ld. In this case, if the approach communication link La1 added to the connection road link La is a road entering the rotary R, and the exit communication link Ld2 added to the connection road link Ld is a road exiting the rotary R, the angle difference between both roads Therefore, guidance in the left-right direction with the direction of returning to the left is performed. However, in this case, since the driver has traveled on the connecting road link La, the left-right guidance for turning left at the rotary R is guidance that matches that feeling.

  As described above, by using the dummy link, when entering the rotary R from the connection road link La and exiting to the connection road link Ld, the guidance direction in the rotary R is the left turn direction, and the distance between the transportation vehicles is increased. Matched direction guidance can be performed.

  The preferred embodiments of the present invention have been described above. However, the route guidance apparatus according to the present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the spirit of the present invention. Can do.

  For example, in the above-described embodiment, the example in which the dummy link is set for the rotary in which the entrance communication link and the exit communication link are interposed between the connection road link and the rotary link has been described. However, it is preferable that this dummy link is set for all the roundabouts regardless of the presence / absence of the incoming contact link and the outgoing contact link. Thereby, it can prevent changing the process for the guidance of the advancing direction for every rotary. Furthermore, it is possible to share part of the processing for guiding the direction in which the vehicle should travel at the roundabout and the normal intersection.

It is a block diagram which shows schematic structure of the navigation apparatus for vehicles concerning embodiment of this invention. It is a flowchart which shows the main routine which a navigation device for vehicles performs for a map display etc. It is a flowchart which shows the detail of the route guidance process in the flowchart of FIG. It is explanatory drawing for demonstrating an example of rotary R. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Position detector 6 ... Map data input device 7 ... Operation switch group 8 ... Navigation ECU
DESCRIPTION OF SYMBOLS 9 ... External memory 10 ... Display apparatus 11 ... VICS receiver 20 ... Vehicle navigation apparatus

Claims (5)

Current position detecting means for detecting the current position of the vehicle;
Map storage means for storing road map data indicating a road by a plurality of links;
A guide route setting means for setting a guide route to reach the destination based on the road map data;
When the current position of the vehicle approaches a guidance target point on the guidance route so that the vehicle travels along the guidance route set by the guidance route setting means, the direction in which the vehicle should travel at the guidance target point is guided. A route guidance device comprising:
The road map data stored by the map storage means includes a dummy link that connects an end of a connection road link connected to a rotary link to which an attribute indicating that it is a rotary is connected to the center of the rotary,
When the roundabout where the dummy link is set becomes a guidance target point, the guidance means includes a first dummy link connected to a connection road link corresponding to a guidance route for entering the roundabout, and exit from the roundabout. The second dummy link connected to the connecting road link corresponding to the guidance route for the vehicle is identified, and the direction in which the vehicle should travel in the rotary is guided based on the angle difference between the first and second dummy links A route guidance device characterized by:   The dummy link is an entry communication link for entering the rotary link that is at least different in direction from the connection road link between the rotary link and at least one connection road link connected to the rotary link. In addition, with respect to a connecting road link with an exit contact link for exiting from the rotary link, the entrance contact link and the exit contact link are excluded with respect to a connecting road link with the entrance contact link and the exit contact link interposed. The route guidance device according to claim 1, wherein the route guidance device is set so as to connect an end portion of the connection road link and a center of the rotary link. A display device;
Display control means for displaying a road map including the guide route on the display device based on the road map data;
3. The route guidance device according to claim 1, wherein the display control unit displays the road map using a plurality of links indicating the road, excluding the dummy links.   The route guidance device according to any one of claims 1 to 3, wherein the guidance means guides a direction in which the vehicle should travel at a guidance target point by voice.   The route guidance device according to any one of claims 1 to 4, wherein the road map data includes the dummy links with respect to all rotary links included in the road map data.

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