JP2001165688A - Navigation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a navigation device capable of facilitating a grasp of the situation of a crossing which a vehicle is entering even in the event of non-route guidance. SOLUTION: During non-route guidance, a guidance timing judging part 20 judges whether there is a crossing within a prescribed distance from the vehicle based on a result of computation of the position and direction of the vehicle and based on map data stored in a data buffer 10. Based on a result of the judgement made by the judging part 20, a crossing guidance part 18 prepares image data corresponding to an enlarged view of the crossing that is within the prescribed distance from the vehicle position and displays it on a display device 7 via an image superimposing part 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation device for displaying a map image around the position of a vehicle, an enlarged view of an intersection where the vehicle passes, and the like.

[0002]

2. Description of the Related Art In general, an on-vehicle navigation device detects the current position of a vehicle, reads map data near the vehicle from a data storage medium such as a CD or DVD, and displays the data on a screen. At the center of the screen, a vehicle position mark indicating the position of the vehicle is displayed. With the vehicle position mark as a center, map data in the vicinity is scrolled according to the progress of the vehicle, and map information around the position of the vehicle is constantly displayed. I understand it.

[0003] Most of the recent on-vehicle navigation devices are equipped with a route guidance function that enables a user to travel to a desired destination without making a mistake on a road. According to this route guidance function, the route with the smallest cost connecting the departure point and the destination is automatically searched for by performing a simulation such as the horizontal search (BFS) method or the Dijkstra method using the map data, and the search is performed. The route is stored as a guidance route. During driving, the guidance route is drawn on the map image in a different color from other roads and is drawn thicker, and is displayed on the screen, and an enlarged map display of the intersection where the vehicle will enter next and guidance voice output are performed. Thus, the user is guided to the destination.

[0004]

In the above-described conventional navigation device, the display of the enlarged view of the intersection is effective only when the route guidance function is used.
At the time of non-guidance, there was a problem that detailed information of the intersection could not be obtained. Therefore, it is difficult for the user to grasp the situation of the intersection where the vehicle is about to enter, and the user may accidentally enter a lane that he does not want at an intersection or the like where the lane setting is complicated. In addition, when such a user tries to obtain detailed information of an intersection where a right or left turn is made, it is necessary to set a guidance route for making a right or left turn at the intersection. It is often difficult to set a guidance route to make a right or left turn at an intersection before approaching the intersection because it is often the case that one wants to know detailed information of the intersection where the vehicle turns left or right while driving. Therefore, it is impossible to obtain detailed information of the intersection after all.

[0005] The present invention has been made in view of the above points, and an object of the present invention is to provide a navigation device that can easily grasp the situation of an intersection where a vehicle enters even during non-route guidance. Is to do.

[0006]

In order to solve the above-mentioned problems, in the navigation device of the present invention, when the vehicle is not guided by the route without using the route guidance function, the navigation device is positioned ahead of the vehicle in the traveling direction by the guidance timing determination means. The display timing of the enlarged view of the intersection is determined, and the enlarged view display means displays the enlarged view of the intersection at this determination timing. Even when the route guidance is not performed, an enlarged view of the intersection existing ahead of the own vehicle in the traveling direction is displayed, so that the user can easily grasp the situation of the intersection where the own vehicle is about to enter. .

The above-mentioned guidance timing determination means determines the display timing of the intersection closest to the vehicle when a plurality of intersections to be displayed in the enlarged view are included within a predetermined distance from the vehicle. It is desirable. When the display timing of the enlarged view of the intersection is considered based on the distance from the vehicle position or the like, the display timing of the next enlarged view of the next intersection may be reached without passing through the nearest intersection. The most necessary information at the time of driving is the information of the next intersection to be turned. By displaying an enlarged view only at the closest intersection, the information required at the time of driving can be displayed.

It is desirable that the above-mentioned guidance timing determination means selectively extracts the intersection for which the display timing is to be determined in accordance with the type of road intersecting the road on which the vehicle is traveling. When the road to be traveled is determined to some extent, for example, when driving only on a national road, or when driving only on a road with a wide width, an unnecessary enlarged view of an intersection is not displayed. By doing so, complicated display switching can be prevented, and a display that is easy for the user to understand can be performed.

In addition, the above-described guidance timing determination means determines a display timing for an intersection in which a road on which the vehicle is traveling includes a plurality of driving lanes, and right and left turns are restricted in some of the driving lanes. It is desirable to make a determination. The convenient case where an enlarged view of the intersection is displayed is when the road on which the vehicle is traveling includes multiple driving lanes, some of which are right turn lanes or left turn lanes. By displaying an enlarged view of the intersection that includes the lane where the left turn is restricted, it is possible to prevent accidentally entering the right turn lane and left turn lane when trying to go straight, and also try to turn right and left In this case, it is possible to accurately enter the right turn lane or the left turn lane.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A navigation device according to an embodiment of the present invention will be described below with reference to the drawings.

(1) Overall Configuration of Navigation Apparatus FIG. 1 is a diagram showing an overall configuration of an on-vehicle navigation apparatus according to an embodiment to which the present invention is applied. The navigation device shown in FIG. 1 includes a navigation controller 1 for controlling the whole, a DVD 2 on which various map data necessary for map display, route search, and the like are recorded, and a disk reading device 3 for reading the map data recorded on the DVD 2. A remote control (remote control) unit 4 as an operation unit for the user to input various instructions; a GPS receiver 5 for detecting a position and a direction of the vehicle; and an autonomous navigation sensor 6
And a display device 7 for displaying a map image, a guidance route, and the like, and an audio unit 8 for outputting a predetermined guidance voice at the time of route guidance.

The above-described disk reading device 3 can load one or a plurality of DVDs 2 and reads map data from any one of the DVDs 2 under the control of the navigation controller 1. The loaded disk is not necessarily a DVD, but may be a CD.
Alternatively, both a DVD and a CD may be selectively loaded.

The remote control unit 4 includes a search key for giving a route search instruction, a route guidance mode key used for setting a route guidance mode, a destination input key, up / down / left / right cursor keys, a map scale / enlargement key, and a display screen. Various operation keys such as a setting key for fixing the item at the upper cursor position are provided, and an infrared signal corresponding to the operation state of the key is transmitted to the navigation controller 1.

The GPS receiver 5 receives radio waves transmitted from a plurality of GPS satellites, performs three-dimensional positioning processing or two-dimensional positioning processing, and calculates the absolute position and direction of the vehicle (the vehicle direction is the current Is calculated based on the own vehicle position and the own vehicle position one sampling time ΔT before), and these are output together with the positioning time. The autonomous navigation sensor 6 includes an angle sensor such as a vibrating gyroscope that detects the vehicle rotation angle as a relative direction, and a distance sensor that outputs one pulse every predetermined traveling distance. Calculate the bearing.

The display device 7 displays a map image around the own vehicle together with a vehicle position mark, a departure point mark, a destination mark, etc., based on image data output from the navigation controller 1, or guides the user on this map. Or show directions.

(2) Details of Map Data Next, details of the map data recorded on the DVD 2 will be described. The map data recorded on the DVD 2 is in units of rectangular figures separated by predetermined longitude and latitude, and the map data of each figure is specified by specifying a figure number and can be read out. It becomes possible. FIG.
Is a diagram showing the contents of map data for each figure. FIG.
As shown in the figure, the map data for each plot includes a drawing unit consisting of various data necessary for map display, and a road unit consisting of data necessary for various processes such as map matching, route search, and route guidance. And an intersection unit composed of detailed data such as an intersection. Also,
The drawing unit described above includes data of a background layer necessary for displaying a building or a river, and data of a character layer required for displaying a municipal name, a road name, and the like.

FIG. 3 is a diagram showing the detailed contents of the road name table included in the character layer of the drawing unit. As shown in FIG. 3, the road name table includes a road name record corresponding to each road included in the target leaf, and each road name record includes: a. Route number b. A road type code indicating the content of this road (expressway, city expressway, national road, etc.); c. Route codes corresponding to route numbers such as national roads and prefectural roads d. Route name reading kana character string e. Route name character string etc. are included.

In the road unit shown in FIG. 2, a line connecting an intersection on a road to another adjacent intersection is called a link, and an intersection connecting two or more links is called a node. FIG. 4 is a diagram showing detailed contents of various tables included in the road unit. As shown in FIG. 4, the road unit includes a unit header for identifying the road unit, a connection node table storing detailed data of all nodes, and a node table indicating a storage position of the connection node table. And a link table storing detailed data of a link specified by two adjacent nodes.

FIG. 5 is a diagram showing the detailed contents of various tables included in the road unit. As shown in FIG. 5A, the node table includes node records # 0, # 1,... Corresponding to all the nodes included in the target leaf.
Is stored. Each node record is #
Node numbers are given in order from 0, and indicate the storage position of the connection node table corresponding to each node.

FIG. 5B shows the connection node table.
For each of the existing nodes, a. Normalized longitude / latitude b. An intersection node flag indicating whether or not this node is an intersection node, an adjacent node flag indicating whether or not this is a node at a boundary with another figure leaf, and whether or not a link has branched at this node. If so, a “node attribute flag” including, for example, branch road information indicating whether the shape of the branch corresponds to a T-junction or a Y-junction; c. "The number of connected nodes" indicating the number of nodes forming the other end of each link when there is a link having this node as one end of the link; d. No right turn or U
If there are traffic restrictions such as turn prohibition, the "number of traffic restrictions", e. Connection node records for the number of links indicating the link number of each link having this node at one end; f. A traffic regulation record indicating the specific content of the traffic regulation corresponding to the number of the traffic regulations, if any, g. If this node is a node at a boundary with another figure leaf, an “adjacent node record” indicating the position of the connection node table of the corresponding node of the neighboring figure leaf, h. If this node is an intersection node, the storage location and size of the corresponding intersection record in the intersection unit are included.

As shown in FIG. 5C, the link table includes a plurality of link records in the order of link numbers corresponding to all the links included in the target figure. Each of these link records: a. A link ID, which is a code assigned to each link mainly for route search display; b. Node number 1 and node number 2 identifying the two nodes located at both ends of the link; c. Link distance, d. The cost of traveling on this link, e. Various road attribute flags including attribute information of the road associated with this link (whether or not there is one-way traffic); f. A road type flag indicating the type of road such as whether the actual road corresponding to this link is an expressway or a general road, and the width of the road such as how many meters the road is; g. The route number assigned to the road corresponding to this link is included.

FIG. 6 is a diagram showing the detailed contents of the intersection unit. As shown in FIG. 6, the intersection unit forms, for each intersection, an intersection record including data on the intersection itself, an intersection direction information record including data on a destination of a road extending from the intersection, and the like. An intersection lane information record or the like including data on each lane of the road is stored.

Each intersection record is, as shown in FIG.
For each of the existing intersections: a. An "intersection information flag" including a signal flag indicating whether or not a signal is standing at this intersection; b. "Number of differences at intersection" indicating how many differences this intersection is, c. Display coordinates for displaying the intersection name; d. Intersection name string to be displayed, e. The link ID of each link constituting the intersection, the storage position of the intersection direction information record corresponding to the link (for the number of roads at the intersection), and the like are included.

(3) Details of Navigation Controller
Configuration and Operation Next, a detailed configuration of the navigation controller 1 shown in FIG. 1 will be described. The navigation controller 1 includes a data buffer 10 for displaying a predetermined map image, an enlarged view of an intersection, and the like on the display device 7, a map readout control unit 12, a map drawing unit 14, a VRAM 16, an intersection guidance unit 18, a guidance timing determination unit. 20, image synthesis unit 2
2, a vehicle position calculation unit 30, a route search processing unit 32, a guidance route drawing unit 34, and a mark image for performing calculation of the vehicle position, map matching processing, route search processing, and route guidance processing and displaying the results. The drawing unit 36 displays various operation screens for the user, and the remote control unit 4
Remote control unit 6 for transmitting operation instructions from the user to each unit
0, a cursor position calculator 62, and an operation screen generator 64.

The data buffer 10 temporarily stores map data read from the DVD 2 by the disk reading device 3. When the vehicle position is calculated by the vehicle position calculation unit 30, the map read control unit 12 sends a read request for map data in a predetermined range including the vehicle position to the disk reading device 3, and outputs a map necessary for map display. Data is read from the DVD 2 and stored in the data buffer 10.

The map drawing section 14 creates map image data necessary for display based on the drawing units included in the map data stored in the data buffer 10. The created map image data is stored in the VRAM 16.

The intersection guide unit 18 provides guidance at the intersection where the vehicle is approaching by using a display image and voice. When the vehicle is actually guided, the vehicle approaches within a predetermined distance from the intersection ahead of the guidance route. Then, image data corresponding to the guide map of the approaching intersection (intersection enlarged view, travel direction arrow) is created, and the travel direction and the like are guided by audio through the audio unit 8. Further, even when the route guidance is not performed, when the own vehicle approaches within a predetermined distance from the intersection existing ahead in the traveling direction, the intersection guide unit 18 displays an image corresponding to an enlarged view of the approaching intersection. Create data. In addition, the intersection guidance part 18 of this embodiment
Does not generate image data corresponding to the traveling direction arrow or output guidance by voice when the route guidance is not performed.

The guidance timing determination section 20 determines whether or not an intersection existing ahead of the vehicle in the traveling direction is within a predetermined distance from the vehicle position during non-route guidance without performing the route guidance. When the vehicle is within the distance, an instruction is output to the intersection guide unit 18 to create image data corresponding to the enlarged view of the intersection. Details of the operation performed by the guidance timing determination unit 20 will be described later.

The image synthesizing section 22 superimposes the map image data read from the VRAM 16 and the image data output from each of the guidance route drawing section 34, the mark image drawing section 36, and the operation screen generating section 64 to perform image synthesis. , And outputs the composite image data to the display device 7. When the intersection guide unit 18 outputs image data corresponding to an intersection guide map such as an enlarged intersection map, the image combining unit 22
Outputs the image data to the display device 7.

The vehicle position calculation unit 30 calculates the position of the vehicle based on the data detected by the GPS receiver 5 and the autonomous navigation sensor 6, and when the calculated vehicle position is not on the road in the map data. Then, a map matching process for correcting the own vehicle position is performed. The route search processing unit 32 searches for a traveling route that connects a preset destination and departure place under predetermined conditions. For example, under various conditions such as the shortest distance and the shortest time, a guidance route with the lowest cost is set. As typical methods of route search, the Dijkstra method and the horizontal search method are known. Guide route drawing unit 34
Creates guidance route drawing data for displaying the guidance route set by the route search processing unit 32 in a superimposed manner on the map image. The mark image drawing unit 36 generates a vehicle position mark at the own vehicle position after the map matching processing, or generates a cursor mark having a predetermined shape.

The data buffer 10 corresponds to the storage means, the guidance timing determination section 20 corresponds to the guidance timing determination means, and the display device 7, the intersection guidance section 18, and the image synthesis section 22 correspond to the enlarged view display means.

The entire navigation device and the navigation controller 1 have the above-described configuration. Next, the operation procedure of the enlarged map display of the intersection performed in parallel with the display of the map image around the own vehicle position during non-route guidance. Will be described.

FIG. 8 is a flow chart showing the operation procedure of the navigation apparatus for displaying an enlarged view of an intersection at the time of non-route guidance, and mainly shows the contents of processing performed in the guidance timing determination section 20. During non-route guidance and while the vehicle is running, the guidance timing determination unit 20 determines whether there is an intersection ahead of the own vehicle in the traveling direction and within a predetermined distance from the own vehicle position (step 100) If there is an intersection within a predetermined distance, it is determined whether there are a plurality of intersections (step 101). For example,
The above-mentioned predetermined distance is set to 1 km from the position of the own vehicle, and the guidance timing determination unit 20
Based on the current position and the traveling direction of the own vehicle determined by the above and the map data (road unit or the like) stored in the data buffer 10, the distance from the own vehicle position to each intersection located ahead in the traveling direction is calculated. It is determined whether there is an intersection whose distance is within 1 km.

When there are a plurality of intersections within a predetermined distance, an affirmative determination is made in step 101, and the guidance timing determination unit 20 specifies an intersection closest to the own vehicle position (step 102). Specifically, in step 101 described above, when determining whether there is an intersection within a predetermined distance from the own vehicle position, the distance from the own vehicle position to each intersection is determined. By extracting the intersection having the shortest distance, the intersection closest to the own vehicle position can be specified.

If there are not a plurality of intersections within a predetermined distance from the vehicle position, the above-described step 1 is executed.
In step 01, a negative determination is made, and the guidance timing determination unit 20 specifies the intersection determined to be within a predetermined distance from the own vehicle position in step 100 as the closest intersection from the own vehicle position.

When the intersection closest to the own vehicle position is specified, the guidance timing determination unit 20 causes the intersection guidance unit 18 to create image data corresponding to an enlarged view of the intersection.
Output instructions to The intersection guidance unit 18 receiving the instruction from the guidance timing determination unit 20 stores the data buffer 1
The map data (drawing unit and the like) stored in 0 is read out, and image data corresponding to an enlarged view of an intersection closest to the own vehicle position is created and displayed on the display device 7 (step 103).

FIG. 9 is a view showing an example of an enlarged view of an intersection displayed at the time of non-route guidance by the processing shown in step 103 described above. An enlarged view of an intersection corresponding to a branch point on an expressway or the like is shown in FIG. The displayed state is shown. FIG. 10 is a diagram showing an example of an enlarged view of an intersection displayed at the time of route guidance in a conventional navigation device. As shown in FIG. 10, in the conventional navigation device, only at the time of route guidance, an enlarged view of an intersection including an image 200 such as an arrow indicating the traveling direction of the vehicle is displayed, and a sound (for example, "Turn right 500m ahead" etc.) was output. However, in the navigation device of the present embodiment, even when the route guidance is not performed, if there is an intersection within a predetermined distance from the own vehicle position, an enlarged view of the intersection is displayed as shown in FIG. In addition, the user can easily acquire information on the intersection where the vehicle is approaching. Although FIG. 9 shows a display example in which the enlarged view of the intersection is displayed on the entire screen of the display device 7, the enlarged view of the intersection may be displayed in a partial area of the screen.

Next, based on the vehicle position calculated by the vehicle position calculation unit 30, the guidance timing determination unit 20 determines whether or not the vehicle has passed the intersection where the enlarged map is currently being displayed. A determination is made (step 104). If the vehicle has not yet passed the intersection where the enlarged view is displayed, a negative determination is made in step 104,
The enlarged view display is continued. Also. When the vehicle passes through the intersection where the enlarged map is displayed, the guidance timing determination unit 20 returns to step 100 and performs the operation after determining whether there is an intersection within a predetermined distance from the vehicle position. repeat.

As described above, in the navigation device according to the present embodiment, when the route guidance is not performed, the guidance timing determining unit 20 determines that the intersection existing ahead in the traveling direction of the own vehicle is within a predetermined distance from the own vehicle position. It is determined whether or not the vehicle has entered, and if a positive determination is made, an enlarged view of the intersection existing ahead of the vehicle in the traveling direction of the own vehicle by the intersection guide unit 18 based on the map data stored in the data buffer 10. Is generated, and this image is displayed on the display device 7. Therefore, even when non-route guidance is performed, an enlarged view of the intersection existing ahead of the own vehicle in the traveling direction is displayed, so that the driver can easily grasp the situation of the intersection where the own vehicle is about to enter. .

In particular, when a plurality of intersections exist within a predetermined distance, an enlarged view is displayed only for the closest intersection, so that an enlarged view of another intersection is displayed before passing through the closest intersection. That is, it is possible to display only necessary information at the time of driving.

The present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention. In the above-described embodiment, all the intersections that are present ahead of the own vehicle in the traveling direction and that are within a predetermined distance are set as the display targets of the enlarged view. However, the intersections to be displayed on the enlarged view are selectively extracted. You may do so.

For example, when an intersecting road is a main arterial road such as a national road or a prefectural road, an enlarged view of an intersection is displayed. When an intersecting road has a width equal to or more than a predetermined value, an enlarged view of an intersection is displayed. If the road on which the vehicle is traveling includes a plurality of driving lanes and a part of the lane is restricted from turning left or right (when there is a right turn lane or a left turn lane), an enlarged view of the intersection is displayed. Whether or not the intersecting road is a national road or a prefectural road, and the width of the road can be known by examining the “road type flag” included in the link record shown in FIG. 5C. In addition, as for restrictions on turning right and left, the “traffic regulation record” included in the connection node table shown in FIG. 5B and the “road attribute flag” included in the link record shown in FIG. You can know by checking.

When the vehicle is to be driven only on a wide road such as a main arterial road, unnecessary display of intersections intersecting with other roads is prevented from being performed, so that complicated display is performed. Switching can be prevented, and a display that is easy for the user to understand can be provided. In addition, by displaying only an enlarged view of an intersection having restrictions such as right and left turns, it is possible to prevent a person from accidentally entering a right turn lane or a left turn lane while trying to go straight, and to make a right / left turn. In this case, it is possible to accurately enter the right turn lane or the left turn lane. Further, by selectively displaying the enlarged view of the intersection as described above, the processing load for performing the enlarged view display can be reduced, and the display screen can be prevented from being frequently switched.

In the above-described embodiment, when an intersection existing in the straight ahead direction within a predetermined distance from the current position of the own vehicle enters within a predetermined distance, an enlarged view of the intersection is displayed. (If there is another intersection closer to the own vehicle position, after passing through this other intersection), the timing of displaying the enlarged view of this intersection depends on the type of road on which the own vehicle is traveling It may be changed according to the above. For example, when traveling on an expressway, the predetermined distance may be set to about 1 km, and when traveling on a general road other than the expressway, the predetermined distance may be set to about 300 m. . By doing so, it is possible to reduce the variation in the time from when the enlarged view of the intersection is displayed until the vehicle actually reaches the intersection.

[0045]

As described above, according to the present invention, even when no route guidance is performed, an enlarged view of an intersection existing ahead in the traveling direction of the own vehicle is displayed. It is possible to easily grasp the situation of the intersection where the car is about to enter.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an overall configuration of a vehicle-mounted navigation device according to an embodiment.

FIG. 2 is a diagram showing the contents of map data for each leaf.

FIG. 3 is a diagram showing detailed contents of a road name table included in a character layer of a drawing unit.

FIG. 4 is a diagram showing detailed contents of various tables included in a road unit.

FIG. 5 is a diagram showing detailed contents of various tables included in a road unit.

FIG. 6 is a diagram showing detailed contents of an intersection unit.

FIG. 7 is a diagram showing detailed contents of an intersection record.

FIG. 8 is a flowchart showing an operation procedure of a navigation device that displays an enlarged view of an intersection during non-route guidance.

FIG. 9 is a diagram illustrating an example of an enlarged view of an intersection displayed during non-route guidance.

FIG. 10 is a diagram showing an example of an enlarged view of an intersection displayed during route guidance in a conventional navigation device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Navigation controller 7 Display device 10 Data buffer 14 Map drawing part 16 VRAM 18 Intersection guidance part 20 Guidance timing judgment part 22 Image synthesis part 30 Vehicle position calculation part

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C032 HB02 HB06 HB22 HC08 HC23 HC24 HC31 HD04 HD16 HD30 2F029 AA02 AB01 AB07 AB13 AC02 AC06 AC09 AC14 AC18 AC19 AD07 5H180 AA01 BB13 BB15 CC12 FF04 FF05 FF22 FF25 FF27 FF27 FF27

Claims (4)

[Claims] 1. A navigation device having a route guidance function, comprising: storage means for storing map data necessary for displaying an enlarged view of an intersection; and enlarging an intersection located ahead of the vehicle in a traveling direction when a route is not guided. Guidance timing determination means for determining the display timing of the figure; and an enlarged view display for displaying the enlarged view based on the map data stored in the storage means at the display timing determined by the guidance timing determination means. And a navigation device. 2. The vehicle according to claim 1, wherein the guidance timing determination unit determines that the distance to the vehicle is closest when a plurality of intersections to be displayed on the enlarged view are included within a predetermined distance from the vehicle. A navigation device for determining the display timing for an intersection. 3. The guide timing determination unit according to claim 1, wherein the guidance timing determination unit selectively selects the intersection to be the display timing determination target according to a type of a road intersecting a road on which the vehicle is traveling. A navigation device characterized by extracting. 4. The vehicle according to claim 1, wherein the guidance timing determination unit includes a plurality of driving lanes on a road on which the vehicle is traveling, and turns right and left on a part of these driving lanes. Wherein the display timing is determined for the intersection where the restriction is made.