JP3533957B2 - Navigation 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 navigation device capable of presenting a recommended route consisting of road sections that are easy to drive.

[0002]

2. Description of the Related Art As a conventional navigation device, for example, one described in Japanese Patent Laid-Open No. 9-292251 has been reported.

In this navigation device, the locus data when the own vehicle travels is stored, and thereafter, based on the locus data at the time of route search, the average speed and the traveling in the road section (link) that has traveled in the past are stored. The time is calculated to avoid selecting a congested road as a route.

[0004]

However, in the conventional navigation device, in order to avoid a vehicle parked on the road, the vehicle temporarily travels in the oncoming lane beyond the center line or on a narrow road. Therefore, even when the vehicle travels on a road where it is necessary to travel by approaching the shoulder to avoid an oncoming vehicle, only the average traveling speed and traveling time are stored as the stored information.

Therefore, even if the driver runs on such a road once and wants to exclude it from the next route, since the stored locus data is only the average speed and the traveling time, the route is re-established. There was a problem that it was more likely to be adopted during the search.

The present invention has been made in view of the above,
It is an object of the present invention to provide a navigation device capable of presenting a recommended route including a road section that is easy to drive.

[0007]

The invention according to claim 1 is
In order to solve the above-mentioned problems, map information storage means for storing in advance map information including road shape information for each road section, current position measuring means for detecting the current position of the vehicle, and road section corresponding to the current position of the vehicle Is read from the map information storage means, and the current position within this road section is stored as travel locus information, the travel locus information read from the travel locus storage means, and the road shape information read from the map information storage means. And a meandering degree calculating means for calculating the meandering degree on the traveling locus by comparing each of the road sections, and a map information adding means for storing the calculated meandering degree in the map information storage means so as to add the calculated meandering degree to the road section. , A route searching means for searching a candidate route from the starting point to the destination and the meandering degree of the road section forming the candidate route from the map information storing means, and setting a predetermined reference value. A section extracting means for extracting a road section with example no meandering degree, and summarized in that and a route guidance means for performing display to route guidance with the route from the extracted road section as a recommended route.

In order to solve the above-mentioned problems, a second aspect of the present invention solves the above-mentioned problems by a map information storage means for storing in advance map information for each road section, a current position measuring means for detecting the current position of the vehicle, and a traveling of the vehicle. A distance measuring means for measuring a distance, a road locus storing means for reading out a road section corresponding to the current position of the vehicle from the map information storing means, and storing a traveling distance in this road section as traveling locus information, and a traveling locus storing means. The meandering degree calculating means for calculating the meandering degree on the traveling locus by comparing the traveled distance for each road section read from the road information with the distance for the road section read out from the map information storage means, and the calculated meandering degree for the road. Map information addition means to be stored in the map information storage means so as to be added to the section, route search means for searching for a candidate route from the starting point to the destination, and a candidate from the map information storage means A section extracting unit that reads out the meandering degree in a road section that forms a road and extracts a road section having a meandering degree that does not exceed a predetermined reference value, and displays a route including the extracted road section as a recommended route. The gist is that it is provided with route guidance means for providing guidance.

In order to solve the above-mentioned problems, a third aspect of the present invention is directed to a map information storage means for storing in advance map information for each road section, a current position measuring means for detecting the current position of the vehicle, and a straight traveling of the vehicle. A shake measurement unit that measures the number of shakes in a direction and a road section corresponding to the current position of the vehicle are read from the map information storage unit, and the map information is added so that the number of shakes in this road section is added as a meandering degree to each road section. The map information adding means stored in the storage means, the route searching means for searching a candidate route from the starting point to the destination, and the meandering degree in the road section forming the candidate route are read out from the map information storing means, and a predetermined reference value is read. Section extracting means for extracting a road section having a meandering degree not exceeding, and route guiding means for displaying a route including the extracted road section as a recommended route and performing route guidance. And summarized in that with a.

In order to solve the above problems, the invention according to claim 4 communicates the degree of meandering for each road section with a traffic information center that collects road information and provides the collected road information to the vehicle side. The gist is to have an information communication means for performing.

[0011]

According to the present invention, the map information including the road shape information for each road section is stored in advance, the road section corresponding to the current position of the vehicle is read out, and this road section is read. The current position inside is stored as traveling locus information. Then, the traveling locus information and the road shape information are compared for each road section to calculate the meandering degree on the traveling locus, and the meandering degree is stored for each road section. Here, when searching for a candidate route from the starting point to the destination, the meandering degree in the road section forming the candidate route is read, and a road section having a meandering degree not exceeding a predetermined reference value is extracted, and this extraction is performed. Since the route including the selected road section is displayed as the recommended route and the route guidance is performed, it is possible to present the route including the easy-to-run road section. As a result, the number of parked vehicles is small, and it is possible to travel on the recommended route with less friction with the oncoming vehicle, which can contribute to the improvement of safety and comfort during traveling.

According to the second aspect of the present invention, the map information for each road section is stored in advance, the road section corresponding to the current position of the vehicle is read out, and the traveled distance in this road section is the traveling locus. Store as information. Then, the traveling distance for each road section and the distance for the road section are compared to calculate the meandering degree on the traveling locus, and the meandering degree is stored for each road section. Here, when searching for a candidate route from the starting point to the destination, the meandering degree in the road section forming the candidate route is read, and a road section having a meandering degree not exceeding a predetermined reference value is extracted, and this extraction is performed. Since the route including the selected road section is displayed as the recommended route and the route guidance is performed, it is possible to present the route including the easy-to-run road section. As a result, the number of parked vehicles is small, and it is possible to travel on the recommended route with less friction with the oncoming vehicle, which can contribute to the improvement of safety and comfort during traveling.

According to the present invention, the map information for each road section is stored in advance, the road section corresponding to the current position of the vehicle is read out, and the number of shakes in this road section is determined as the meandering degree. Is stored for each road section. Here, when searching for a candidate route from the starting point to the destination, the meandering degree in the road section forming the candidate route is read,
A road section that has a meandering degree that does not exceed a predetermined reference value is extracted, and a route that includes the extracted road section is displayed as a recommended route to provide route guidance. be able to. As a result, the number of parked vehicles is small, and it is possible to travel on the recommended route with less friction with the oncoming vehicle, which can contribute to the improvement of safety and comfort during traveling.

According to the fourth aspect of the present invention, the meandering degree of each road section is communicated with a traffic information center that collects road information and provides the collected road information to the vehicle side. Therefore, when the meandering degree for each road section stored in the own vehicle is transmitted to the traffic information center, the meandering degree for each road section can be provided from the traffic information center to other vehicles.

Further, when the meandering degree for each road section collected in the traffic information center is received, it is possible to accurately search for a recommended route with a small number of parked vehicles and a small difference in friction with an oncoming vehicle. As a result, it is possible to contribute to the improvement of safety and comfort during traveling.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a block configuration diagram of a navigation device according to a first embodiment of the present invention.

The operation unit 1 has a touch panel, buttons and the like, and inputs plan information such as a departure place, a destination and a desired arrival time for planning a travel route. The map information recording unit 3 is
On a recording medium such as a additionally writable CD-ROM, road information including road shape information indicating the shape of the road, facility information, etc. are recorded as position information such as latitude and longitude, and
It is possible to read this information. The route search unit 5 searches for a candidate route from the starting point to the destination based on the plan information input from the operation unit 1 and the map information from the map information recording unit 3. The current position measuring unit 7 is GP
It has an S receiver and the like and measures the current position of the vehicle based on time information received from a plurality of GPS satellites.

The route guide unit 9 searches the candidate routes searched,
Based on the current position obtained by the current position measuring unit 7 and the map around the current position read from the map information recording unit 3, a route which can be traveled in the shortest time is determined from the candidate routes of this time, The route guidance is displayed on the display unit 11. Further, the route guidance unit 9 divides into a plurality of shorter traveling sections according to the roads existing for each candidate route, and examines the sections having the shortest time.

The traveling locus storage unit 13 includes a current position measuring unit 7
The position information of the vehicle sent from is stored as a traveling locus. The meandering degree calculation unit 15 compares the traveling locus information read from the traveling locus storage unit 13 with the road information read from the map information storage unit 3 by the link extraction unit 19, and the comparison result is sent to the map information addition unit 17. Output.

The map information adding section 17 is a meandering degree calculating section 1
The calculation result from 5 is added to the road information of the road stored in the map information storage unit 3 as incidental information of the road.
The added information is later referred to from the route search unit 5 via the link extraction unit 19 and used for route search. The link extraction unit 19 reads out the meandering degree of the road section forming the candidate route from the map information storage unit 3 and extracts the road section having a meandering degree not exceeding a predetermined reference value.

The arithmetic and control unit 21 has a CPU and RO inside.
M, RAM, a timer, etc., and according to the control program and calculation program stored in the internal ROM, the above-mentioned route search unit 5, route guidance unit 9, travel locus storage unit 13,
The processing functions of the software modules such as the meandering degree calculating unit 15, the map information adding unit 17, and the link extracting unit 19 are executed.

Next, with reference to the flow chart shown in FIG. 2, a process for calculating the supplementary information to be added on the road link will be described. First, in step S10, the vehicle position information measured by the current position measuring unit 7 during traveling is stored in the traveling locus storage unit 13 as traveling locus information of the vehicle for each road link stored in the map information storage unit 3. Keep it.

More specifically, when the positioning signal transmitted from the GPS satellite is used, the latitude and longitude on the earth can be detected with an accuracy of several meters. As shown in FIG. 3, points sampled every 5 m on the road link are measured. Then, the current position information is stored in the traveling locus storage unit 13 as traveling locus information. Then, in step S20, the meandering degree calculation unit 15 calculates the meandering degree of the vehicle by comparing the shape of the road link and the traveling locus information for each road link (road section).

Here, the method of calculating the meandering degree in step S20 described above will be described in detail with reference to the flowchart shown in FIG. First, in order to collect the degree of meandering, in step S40, one road link (one section) is extracted from the road on which the vehicle has traveled as a calculation target.

Next, in step S50, as shown in FIG. 5, the road link shape L (almost straight line section) and the traveling locus D are shown.
(S-shaped curve) is developed on an arbitrary coordinate axis XY, and the absolute value of the difference between D (X) and L (X) along the coordinate axis X | D
The integrated value from the starting point S to the ending point E of the road link for (X) -L (X) |, that is, the curve D (X) and the straight line L
The area of the shaded area surrounded by (X) is calculated.

[0026]

[Equation 1] Area = ∫ | D (X) −L (X) | Then, the area value is divided by the road link distance to obtain a meandering degree value indicating the degree of meandering per unit distance.

[0027]

[Equation 2] Meandering degree = {∫ | D (X) -L (X) |} / road link distance Note that the road link section distance is a node of two points on the map stored in the map information storage unit 3. It is obtained by connecting with a straight line. Then, in step S60, the obtained meandering degree is stored in the map information storage unit 3 via the map information addition unit 17 as supplementary information of the road link.

Although FIG. 5 shows an example of meandering the traveling route for one cycle centering on the road link, meandering for a plurality of cycles is more realistic as shown in FIG. Figure 6
As shown in Fig. 5, when the vehicle actually travels on the road, meandering occurs several times even on one road link due to parking on the shoulder, passing of a slow vehicle, etc. Therefore, the calculation shown in FIG. ).

Since there are three road links AB, BC and CD on the road shown in FIG. 3, step S70 is performed.
Then, it is checked whether there are any road links for which the "meander degree" has not been calculated yet. If there is a road link that has not been calculated, the process returns to step S40 and the above-described processing is repeated for that road link.

On the other hand, when the calculation of the "meandering degree" is completed for all the traveling records, the processing is completed. Returning to FIG. 2, in step S30, the calculated “meandering degree” value is stored in the map information storage unit 3 via the map information storage unit 17 as incidental information of the target road link.

Next, the route search process of the navigation device will be described with reference to the flowchart shown in FIG. It is assumed that the map information storage unit 3 stores the “meandering degree” by the above-described processing. First, in step S80, the route search unit 5 searches the map information storage unit 3 for a candidate route from the starting point to the destination input by the operation unit 1 based on the well-known Dijkstra method.

Then, in step S90, the road that has traveled in the past among the searched road links on the candidate route and the "meandering degree" is stored in the map information storage unit 3 as additional information of the road link. The link extracting unit 19 extracts one link.

Here, in step S100, for example, the "upper limit value of the meandering degree adopted as the route" input by the driver from the operation unit 1 is compared with the meandering degree corresponding to the road link. The upper limit value of the meandering degree adopted as the route may be input by the user in advance, or may be a value set as an initial value in the arithmetic control unit 21 in advance.

When the meandering degree does not exceed the upper limit value, the process proceeds to step S110, and the road link is designated as one section of the candidate route and sent to the route guidance unit 9. Here, in step S120, it is checked whether or not the road links in the candidate routes which have not undergone the comparison determination in step S100 remain. If the comparison and determination have not been completed for all road links in the candidate route, the process returns to step S90 and the above-described processing is repeated.

In step S110, when the meandering degree is larger than the upper limit value, the process proceeds to step S130, and the route search unit 5 does not adopt the road link as a part of the traveling route. In this case, after notifying the route guidance unit 9 of the rejection flag indicating that this road link is not used, the process returns to step S80, and the route search unit 5 re-searches for a candidate route to the destination.

On the other hand, in step S120, since all the driven road links in the candidate route have been determined, the process ends. As a result, among the candidate routes, a route including a plurality of road links whose meandering degree does not exceed the upper limit value is sent to the route guidance unit 9, and the determined route is displayed on the display unit 11.

In this way, the current position of the vehicle is measured by the current position measuring unit 7, the road link corresponding to the current position of the vehicle is read from the map information storage unit 3, and the current position in this road link is the traveling locus information. It is stored in the traveling locus storage unit 13 as. Here, the traveling locus information read from the traveling locus storage unit 13 and the road shape information read from the map information storage unit 3 are compared by the meandering degree calculation unit 15 for each road link to calculate the meandering degree on the traveling locus. To do. The calculated meandering degree is added to the map information for each road link 17
To be added to the map information storage unit 3 and stored. Furthermore, when the route search unit 5 searches for a candidate route from the starting point to the destination, the meandering degree at the road link forming the candidate route is read from the map information storage unit 3 and the meandering degree not exceeding a predetermined reference value. Link extraction unit 1 for road links having
Extract at 9. Then, the route consisting of the extracted road links is handed over from the route searching unit 5 to the route guiding unit 9 as a recommended route and is displayed on the display unit 11 to guide the route, so that a route consisting of a road section that is easy to drive is presented. can do. As a result, the number of parked vehicles is small, and it is possible to travel on the recommended route with less friction with the oncoming vehicle, which can contribute to the improvement of safety and comfort during traveling.

(Second Embodiment) Next, FIG. 8 is a block diagram of a navigation apparatus according to a second embodiment of the present invention. In the configuration of the second embodiment shown in FIG. 8, the wheel rotation measuring unit 27 is added to the configuration of the first embodiment, and the description of the same components will be omitted.

The wheel rotation measuring section 27 measures the pulse signal output from the rotation speed sensor provided on the wheel 25 at predetermined time intervals to detect the rotation speed of the wheel. Since the circumferential length of the wheel is known in advance, the wheel rotation measuring unit 27

[Equation 3] (rotational speed) × (circumferential length of wheel) = traveling distance can also be obtained. The calculated traveling distance is sent to the traveling locus storage unit 13. Then, the traveling locus storage unit 13 stores the traveling distance for each road section as a traveling locus.

In the first embodiment, the traveling locus D (X)
Absolute value of the difference between the road link L (X) and the road link | D (X) -L
A value obtained by dividing the integral value from the starting point S to the ending point E of the road link for (X) | by the distance of the road link is obtained, and in step 50 shown in FIG. 4, a “meandering degree” indicating the degree of meandering is calculated. The value is stored in the map information storage unit 3 as incidental information of the road link.

In the second embodiment, the following calculation is performed instead of step S50. The meandering degree calculation unit 5 calculates a value obtained by dividing the difference between the distance L of the road link and the actual traveling distance D by the distance L of the road link to obtain the meandering degree.

[0042]

[Formula 4] Meandering degree = (D−L) / L Becomes

In FIG. 9, all road links AB,
It is the figure which displayed each road link of BC and CD in piles.
Now, as shown in Formula 4, the difference between the length of the traveling locus D obtained from the rotational speed of the wheels and the length L of all road links from the point A to the point D is divided by the length L of the road link. The degree of meandering per unit distance is calculated and stored in the map information storage unit 3 as incidental information of the road. Using such a “meandering degree”, a route search is performed according to the flowchart shown in FIG.

In this way, the current position of the vehicle is measured by the current position measuring unit 7 and the traveling distance of the vehicle is measured by the wheel rotation measuring unit 27. Then, the road link corresponding to the current position of the vehicle is read from the map information storage unit 3, and the traveling distance on this road link is stored in the traveling locus storage unit 13 as traveling locus information. Then, the travel distance for each road link is compared with the road link distance, the meandering degree on the travel locus is calculated by the meandering degree calculating unit 15, and the meandering degree is stored in the map information storage unit 3 for each road link. deep. Here, when the route search unit 5 searches for a candidate route from the starting point to the destination, the meandering degree of the road links that form the candidate route is read from the map information storage unit 3 and the meandering amount not exceeding a predetermined reference value. The link extracting unit 19 determines a road link having a degree.
Extract with. Since the route including the extracted road links is displayed on the display unit 11 from the route guide unit 9 as a recommended route and the route guidance is performed, it is possible to present a route including road links that are easy to travel.

As a result, the number of parked vehicles can be reduced and the recommended route with less friction with the oncoming vehicle can be traveled, which contributes to the improvement of safety and comfort during traveling.

(Third Embodiment) Next, FIG. 10 is a block diagram of a navigation device according to a third embodiment of the present invention. In the configuration of the third embodiment shown in FIG. 10, the shake measurement unit 31 is added to the configuration of the first embodiment, and the description of the same components will be omitted.

As the value of "meandering degree", "the number of times the vehicle shakes in the road direction" is used. The shake measuring unit 31 includes a gyro and a steering wheel turning angle sensor, calculates the number of times of shake of the vehicle from a swing angle signal with respect to the straight traveling direction of the vehicle, and sends the number of shakes to the map information adding unit 17.

For example, as shown in FIG. 11, points N1 and N
The shake direction is reversed at two points 2 and counted as two shake times. Further, as shown in FIG. 12, between the start point S and the end point E, the shake directions are reversed at five points N1 to N5, and the number of swings and the number of times are counted five times.

As described above, the number of shakes of the vehicle in the straight traveling direction is measured by the shake measuring unit 31, the road link corresponding to the current position of the vehicle is read from the map information storage unit 3, and the number of shakes in the road link is measured. Is stored in the map information storage unit 3 so as to be added to each road link as a meandering degree. Here, when the route search unit 5 searches for a candidate route from the starting point to the destination, the meandering degree of the road links that form the candidate route is read from the map information storage unit 3 and the meandering amount not exceeding a predetermined reference value. The link extraction unit 19 extracts a road link having a degree. Since the route including the extracted road links is displayed on the display unit 11 from the route guide unit 9 as a recommended route and the route guidance is performed, it is possible to present a route including road links that are easy to travel.

As a result, the number of parked vehicles is small, and the recommended route with less friction with the oncoming vehicle can be traveled, which contributes to the improvement of safety and comfort during traveling.

(Fourth Embodiment) Next, a fourth embodiment will be described with reference to FIG. The configuration of the fourth embodiment is obtained by adding the information communication unit 41 to the first embodiment. A description of the same configuration will be omitted.

The information communication unit 41 transmits the meandering degree for each road link stored in the map information storage unit 3 to the traffic information center and receives the meandering degree for each road link collected in the traffic information center. Then, the storage content of the map information storage unit 3 is updated.

The "meandering degree" calculated by the procedure shown in the operation flowchart of FIG. 4 is stored in the map information storage unit 3 and can be transmitted to the external traffic information center by the information communication unit 41. . The traffic information center collects the "meandering degree" information transmitted from many vehicles, subdivides and classifies it based on the time zone and the day of the week, and calculates the meandering degree of each road link. The calculated “meandering degree” of each road link can be received by the information communication unit 41 provided in the vehicle traveling in various places.

As described above, the meandering degree of each road link is communicated between the traffic information center that collects road information and provides the collected road information to the vehicle side and the information communication unit 41. When the meandering degree for each road link stored in the own vehicle is transmitted to the traffic information center, the meandering degree for each road link can be provided from the traffic information center to other vehicles.

Further, when the meandering degree for each road link collected in the traffic information center is received, it is possible to accurately search for a recommended route in which there are few parked vehicles and there is little friction between oncoming vehicles. As a result, it is possible to contribute to the improvement of safety and comfort during traveling.

[Brief description of drawings]

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

FIG. 2 is a flowchart for calculating road link incidental information of the present invention.

FIG. 3 is a diagram showing a difference between a traveling locus and a road link shape in the present invention.

FIG. 4 is a flowchart showing a method of calculating a meandering degree according to the present invention.

FIG. 5 is a diagram for explaining a method of calculating a meandering degree according to the present invention.

FIG. 6 is a diagram showing an example of an actual traveling locus.

FIG. 7 is a flowchart showing an example of a route search using the “meandering degree” in the present invention.

FIG. 8 is a block configuration diagram of a navigation device according to a second embodiment of the present invention.

FIG. 9 is a diagram for explaining a method of calculating a meandering degree according to the second embodiment of the present invention.

FIG. 10 is a block configuration diagram of a navigation device according to a third embodiment of the present invention.

FIG. 11 is a diagram showing an example of calculating a meandering degree with a small number of times in the third embodiment of the invention.

FIG. 12 is a diagram showing an example of calculating a meandering degree with a large number of times according to a third embodiment of the present invention.

FIG. 13 is a block configuration diagram of a navigation device according to a fourth embodiment of the present invention.

[Explanation of symbols]

1 Operation part 3 Map information recording section 5 Route search section 7 Current position measurement section 9 Route guidance section 11 Display 13 Running locus storage 15 Meandering degree calculator 17 Map information addition section 19 Link extractor 21 Operation controller 25 wheels 27 Wheel rotation measurement unit 31 Shake measurement section 41 Information Communication Department

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Claims (4)

(57) [Claims] 1. A map information storage means for storing in advance map information including road shape information for each road section, a current position measuring means for detecting a current position of a vehicle, and a map of a road section corresponding to the current position of the vehicle. The traveling locus storage unit that reads out from the information storage unit and stores the current position in this road section as traveling locus information, the traveling locus information read out from the traveling locus storage unit, and the road shape information read out from the map information storage unit. A meandering degree calculating means for calculating the meandering degree on the traveling locus by comparing each road section, and a map information adding means for storing the calculated meandering degree in the map information storage means so as to add the calculated meandering degree to each road section, The route search means for searching a candidate route from the origin to the destination and the meandering degree in the road section forming the candidate route are read out from the map information storage means and exceed a predetermined reference value. A navigation device comprising: a section extracting unit that extracts a road section having a non-meandering degree; and a route guiding unit that displays a route including the extracted road section as a recommended route and guides the route. 2. A map information storage means for storing map information for each road section in advance, a current position measuring means for detecting a current position of the vehicle, a distance measuring means for measuring a traveling distance of the vehicle, and a current position of the vehicle. The road section corresponding to the road section is read from the map information storage section, and the travel distance in this road section is stored as the travel path information, the travel distance for each road section read from the travel path storage section, and the map information. Meandering degree calculating means for calculating the meandering degree on the traveling locus by comparing the distance of the road section read out from the storing means, and the map information storing means for storing the calculated meandering degree for each road section. Map information adding means, a route searching means for searching a candidate route from the starting point to the destination, and a meandering degree in the road section forming the candidate route from the map information storing means. Provided with section extracting means for extracting a road section having a meandering degree that does not exceed a predetermined reference value, and route guiding means for displaying a route including the extracted road section as a recommended route and performing route guidance. Navigation device. 3. A map information storage means for storing in advance map information for each road section, a current position measuring means for detecting the current position of the vehicle, a shake measuring means for measuring the number of times of shake of the vehicle in a straight traveling direction, and a vehicle. The map information adding means for reading the road section corresponding to the present position from the map information storage means and storing the number of shakes in the road section as the meandering degree for each road section in the map information storage means; Section for searching a candidate route from the vehicle to the destination, and a section for reading out the meandering degree in the road section forming the candidate route from the map information storing section and extracting the road section having a meandering degree not exceeding a predetermined reference value. A navigation device comprising: an extracting unit and a route guiding unit that displays a route including the extracted road section as a recommended route to guide the route. Place 4. An information communication means for collecting road information and communicating the degree of meandering for each road section with a traffic information center that provides the collected road information to the vehicle side. The navigation device according to any one of items 1 to 3.