Route search device

Abstract

To search for a route to a destination that is preferable for a driver. [Solution] The route search device 11 includes an information acquisition unit 161 that acquires driving information including information on the driving positions and / or driving speeds of multiple vehicles, a setting unit 162 that calculates the average driving speed of the multiple vehicles for each road section based on the acquired driving information and sets a difficulty level rank for each road section based on the average value, a memory unit 16B that stores road map information including the difficulty level rank, and a route calculation unit 163 that calculates a driving route that reduces the proportion of driving on roads with a high difficulty level rank. The setting unit 162 sets the difficulty level so that the greater the difference between the average value and a predetermined reference value, the higher the difficulty level rank.

Description

[Technical Field]

[0001] The present invention relates to a route search device that searches for a route to a destination. [Background technology]

[0002] In recent years, efforts to provide access to sustainable transportation systems that take into consideration vulnerable traffic participants have been gaining momentum. Toward this goal, research and development into preventive safety technologies has been conducted. Against this background, a device is known as a technology for assisting drivers when traveling through slow-speed zones. The device acquires road environment information, such as the width and visibility of the road, based on images from an onboard camera, and calculates the passing speed through the slow-speed zone according to the road environment (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-227106 Summary of the Invention [Problem to be solved by the invention]

[0004] However, there are cases where it is preferable for a driver to reduce the proportion of driving in slow-speed sections rather than driving slowly through slow-speed sections, and the device described in Patent Document 1 does not make any suggestions in this regard. [Means for solving the problem]

[0005] A route search device according to one aspect of the present invention comprises a driving information acquisition unit that acquires driving information including information on the driving positions and / or driving speeds of a plurality of vehicles; a difficulty setting unit that calculates the average value of the driving speeds of the plurality of vehicles for each road section based on the driving information acquired by the driving information acquisition unit and sets a difficulty rank indicating the difficulty of driving for each road section based on the average value; a memory unit that stores road map information including the difficulty ranks set by the difficulty setting unit; and a route calculation unit that calculates a driving route to a destination that reduces the proportion of driving on roads with high difficulty ranks stored in the memory unit, and the difficulty setting unit sets the difficulty rank so that the greater the difference between the average value and a predetermined reference value, the higher the difficulty rank.

[0006] Another aspect of the present invention is a route search device that includes a driving information acquisition unit that acquires driving information including information on the driving positions of multiple vehicles; a difficulty setting unit that calculates the average number of lane changes involving reverse driving or U-turn driving by the multiple vehicles for each road section based on the driving information acquired by the driving information acquisition unit, and sets a difficulty rank indicating the difficulty of driving for each road section based on the average value; a memory unit that stores road map information including the difficulty rank set by the difficulty setting unit; and a route calculation unit that calculates a driving route to a destination that reduces the proportion of driving on roads with a high difficulty rank stored in the memory unit, and the difficulty setting unit sets the difficulty rank so that the greater the difference between the average value and a predetermined reference value, the higher the difficulty rank. [Effects of the Invention]

[0007] According to the present invention, it is possible to search for a route to a destination that is preferable for the driver. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a diagram showing an example of roads assumed by the route search device according to the embodiment of the present invention. [Figure 2] 1 is a diagram showing an outline of the overall configuration of a route search system including a route search device according to an embodiment of the present invention; [Figure 3] 1 is a block diagram showing a schematic configuration of a main part of a route search device according to an embodiment of the present invention; [Figure 4] FIG. 10 is a diagram showing the relationship between average speed difference and difficulty rank. [Figure 5] FIG. 10 is a diagram schematically illustrating an example of a target circuit displayed on a monitor. [Figure 6] 4 is a flowchart showing an example of processing executed by the calculation unit of FIG. 3. [Figure 7] FIG. 10 is a diagram showing another example of roads assumed by the route search device according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to Figures 1 to 7. A route search device according to an embodiment of the present invention is a device that searches for a route to a destination when a vehicle is traveling toward the destination, and is configured by, for example, a car navigation device.

[0010] FIG. 1 is a diagram showing an example of a road RD1 assumed by a route search device according to this embodiment. As shown in FIG. 1, various obstacles 201 exist on the road RD1, and the obstacles 201 prevent a vehicle C from traveling in the direction of the arrow. For this reason, when the vehicle C travels on the road RD1, the vehicle C needs to drive at a speed that is well below the legal speed limit. The obstacles 201 are movable objects such as parked vehicles, parked bicycles, and pedestrians. Therefore, the obstacles 201 do not necessarily exist all the time, and the obstacles 201 may be absent or fewer depending on the time of day or the day of the week.

[0011] In this embodiment, the route search device is configured to identify in advance sections (slow driving sections) where the driver is likely to drive slowly based on such driving information (vehicle speed information) of vehicle C, and to calculate a driving route that reduces the proportion of driving through the slow driving sections. This reduces the frequency with which the driver drives through slow driving sections, allowing the driver to drive the vehicle efficiently and safely to the destination. Reducing the frequency with which the driver drives through slow driving sections is particularly desirable for drivers who are inexperienced at driving or who rarely drive through such sections.

[0012] 2 is a diagram schematically illustrating the overall configuration of a route search system 1 including a route search device according to an embodiment of the present invention. As shown in FIG. 2, the route search system 1 includes an on-board device 10 mounted on a vehicle (for convenience, referred to as the host vehicle) 100, a plurality of on-board devices 20 mounted on a plurality of vehicles (for convenience, referred to as other vehicles) 200 different from the host vehicle 100, and a server device 30. For convenience, two other vehicles 200 are shown in FIG. 2, but the number of other vehicles 200 may be three or more. The on-board device 10, the plurality of on-board devices 20, and the server device 30 are capable of communicating with each other via a network 2.

[0013] The network 2 includes not only public wireless communication networks such as the Internet and mobile phone networks, but also closed communication networks established for each predetermined management area, such as wireless LAN, Wi-Fi (registered trademark), Bluetooth (registered trademark), etc. The server device 30 is configured, for example, as a single server or as a distributed server consisting of separate servers for each function. The server device 30 can also be configured as a distributed virtual server created in a cloud environment called a cloud server.

[0014] The subject vehicle 100 is, for example, a rental vehicle provided for a car sharing service. Therefore, the driver is often unfamiliar with driving the subject vehicle 100, and it is preferable to avoid driving the subject vehicle 100 in slow driving zones. On the other hand, the other vehicles 200 include a plurality of rental vehicles and a plurality of non-rented vehicles (e.g., private cars) other than the rental vehicles. Each vehicle is assigned a vehicle ID that identifies the vehicle, and by recognizing the vehicle ID, it is possible to identify whether each vehicle is a rental vehicle or a non-rented vehicle.

[0015] Fig. 3 is a block diagram showing a schematic configuration of a route search device 11 according to an embodiment of the present invention. This route search device 11 is included in the on-board device 10 of the host vehicle 100 shown in Fig. 2. As shown in Fig. 3, the route search device 11 has a positioning sensor 12, a vehicle speed sensor 13, an input unit 14, a communication unit 15, a controller 16, and a monitor 17. The positioning sensor 12, the vehicle speed sensor 13, the input unit 14, the communication unit 15, and the monitor 17 are each communicatively connected to the controller 16.

[0016] The positioning sensor 12 receives positioning signals transmitted from positioning satellites. The positioning satellites are artificial satellites such as GPS satellites and quasi-zenith satellites, and the current position (latitude, longitude, altitude) of the vehicle 100 can be detected using the positioning information received from the positioning satellites by the positioning sensor 12. Therefore, the positioning sensor 12 functions as a position detection unit that detects the position of the vehicle 100.

[0017] The vehicle speed sensor 13 is configured to output a signal corresponding to the vehicle speed of the host vehicle 100, and the vehicle speed of the host vehicle can be detected based on the signal from the vehicle speed sensor 13. The position information detected by the positioning sensor 12 and the vehicle speed information detected by the vehicle speed sensor 13 are transmitted to the server device 30 ( FIG. 2 ) together with the vehicle ID of the host vehicle 100 via the communication unit 15. Although not shown, the in-vehicle device 20 of the other vehicle 200 also has the positioning sensor 12, the vehicle speed sensor 13, and the communication unit 15, and the position information detected by the positioning sensor 12 and the vehicle speed information detected by the vehicle speed sensor 13 are transmitted to the server device 30 together with the vehicle ID of the other vehicle 200 via the communication unit 15.

[0018] The server device 30 in FIG. 2 calculates an evaluation value α1 used to search for a target route based on the position information and vehicle speed information transmitted from the vehicle 100 and multiple other vehicles 200 within a predetermined period T0, such as one month or one year. The evaluation value α1 is the average vehicle speed of multiple other vehicles 200 during a time period when there are no obstacles 201 or few obstacles 201 on the road RD1 (FIG. 1), and corresponds to a reference vehicle speed value. In this case, the time period is a continuous period of time of at least a predetermined period (30 minutes or one hour), and may be morning, midday, evening, night, or the like, or may be morning or afternoon. The time period for calculating the evaluation value α1 may be a period from one time to another. It may also be a time period spanning two or more dates.

[0019] For example, in the morning when there are no obstacles 201 or few obstacles 201, the server device 30 calculates the average value of multiple other vehicles 200 in the morning as the evaluation value α1. The evaluation value α1 is calculated for each road section (link). Note that a link is a section of a road connecting nodes, and may include not only straight sections but also curved sections. A node is an intersection or an end point of a road, that is, the start or end point of a road.

[0020] The evaluation value α1 may be an average value of the vehicle speeds of multiple other vehicles 200 on a day of the week when there are no obstacles 201 or few obstacles 201 on the road RD1. The day of the week on which the evaluation value α1 is calculated is any day from Monday to Sunday, and is a day on which there are no obstacles 201 or few obstacles 201 on the road RD1. Note that the day of the week may be divided into weekdays and holidays, and the evaluation value α1 may be calculated for either the weekday or the holiday. For example, when there are no obstacles 201 or few obstacles 202 on a weekday, the server device 30 calculates the average value of the vehicle speeds of multiple other vehicles 200 for each road section on the weekday as the evaluation value α1.

[0021] The evaluation value α1 may be the legal speed limit for each road section. In this case, the server device 30 sets the legal speed limit included in the road map information as the evaluation value α1. When multiple other vehicles 200 are classified into rented vehicles and non-rented vehicles, the evaluation value α1 may be the average vehicle speed of non-driving vehicles for each road section, calculated using the driving information of multiple non-rented vehicles.

[0022] The input unit 14 in Figure 3 inputs information such as the destination of the vehicle 101 in response to a command from the driver. The controller 16 calculates a target route for the vehicle 100 to the destination, taking into account the link cost. That is, it calculates a target route that minimizes the link cost. The link cost is the cost incurred when passing through a specific link (road section) and is expressed as a numerical value. The lower the link cost, the more reasonable the route found is. When calculating the link cost, factors taken into consideration include the length (distance) of the link, the time and fee required to pass through the link, the type of road corresponding to the link, the width of the road, traffic information, etc. The monitor 17 displays the target route calculated by the controller 16.

[0023] The controller 16 is an electronic control unit including a computer having a calculation unit 16A such as a CUP, a storage unit 16B such as a ROM and RAM, and other peripheral circuits such as an I / O interface. The calculation unit 16A mainly functions as an information acquisition unit 161, a setting unit 162, and a route calculation unit 163. The storage unit 16B stores road map information.

[0024] The information acquisition unit 161 identifies roads from the current location detected by the positioning sensor 12 to the destination indicated by the input unit 14 for bathing, i.e., roads that are candidates for the target route. Then, the information acquisition unit 161 acquires driving information of multiple other vehicles 200 corresponding to each road within a predetermined period T1 from the server device 30 via the communication unit 15. The driving information includes position information and vehicle speed information of the other vehicles 200. The information acquisition unit 161 may be configured to acquire only driving information corresponding to the current time zone or the current day of the week.

[0025] The information acquisition unit 161 also acquires vehicle information of multiple other vehicles 200. The vehicle information includes information as to whether the other vehicles 200 are rented vehicles or non-rented vehicles. The information acquisition unit 161 further acquires, from the server device 30, an evaluation value α1 corresponding to each road to the destination. The information acquired by the information acquisition unit 161 is temporarily stored in the storage unit 15B. Note that the information acquisition unit 161 may also acquire information on a road map leading to the destination.

[0026] The setting unit 162 calculates an average value Va of the driving speeds of multiple other vehicles 200 for the current time period or day of the week for each road section based on the driving information for the predetermined period T1 acquired by the information acquisition unit 161. Furthermore, the setting unit 162 sets a difficulty level rank β ​​indicating the driving difficulty for each road section based on the average value Va. More specifically, when the server device 30 calculates the evaluation value α1 for a predetermined time period, if the current time period is different from the predetermined time period, the setting unit 162 calculates the average value Va of the vehicle speeds for the current time period within the predetermined period T1. For example, if the time period in which the evaluation value α1 was calculated is morning and the current time period is daytime, the setting unit 162 calculates the average value Va of the vehicle speeds for the daytime period within the predetermined period T1.

[0027] The average value Va can be calculated based on signals from the positioning sensors 12 provided in each of the other vehicles 200. That is, the setting unit 162 can calculate the vehicle speed for each road section based on changes in the positions of the other vehicles 200 detected by the positioning sensors 12, and calculate the average value Va using this vehicle speed. The average value Va can also be calculated based on signals from the vehicle speed sensors 13 provided in each of the other vehicles 200. That is, the setting unit 162 can calculate the average value Va for each road section based on the traveling speeds of the other vehicles 200 detected by the vehicle speed sensors 13.

[0028] Furthermore, the setting unit 162 calculates the difference between this average value Va and the evaluation value α1, i.e., the average speed difference ΔV (=α1-Va), and sets a difficulty level rank β ​​according to the average speed difference ΔV. FIG. 4 is a diagram showing the relationship between the average speed difference ΔV and the difficulty level rank β. As shown in FIG. 4, the difficulty level rank β ​​is expressed as an integer from 0 to 5, for example, and the difficulty level rank β ​​increases stepwise as the average speed difference ΔV increases. The higher the difficulty level rank β, the less rational the route is, and the higher the link cost. The calculated difficulty level rank β ​​is stored in the storage unit 16B in association with road map information. As long as the difficulty level rank β ​​increases as the average speed difference ΔV increases, the relationship between the average speed difference ΔV and the difficulty level rank β ​​is not limited to that shown in FIG. 4. For example, the relationship between the average speed difference ΔV and the difficulty level rank β ​​may be represented by a straight line sloping upward to the right.

[0029] The route calculation unit 163 calculates a route to the destination based on the road map information stored in the storage unit 16B. For example, it calculates multiple routes and sets the route with the smallest link cost as the target route. Furthermore, the route calculation unit 163 outputs information about the target route to the monitor 17. As a result, as schematically shown in FIG. 5, a target route RT1 (solid line) from the current point P1 to the destination P2 is displayed on the monitor 17.

[0030] In Figure 5, as a reference example of this embodiment, a target route RT2 when the difficulty level rank β ​​is not taken into consideration is shown by a dotted line. When the difficulty level rank β ​​is not taken into consideration, for example, the shortest route to destination P2 becomes the target route RT2. This target route RT2 includes road RD1, which is the slow driving section in Figure 1. In contrast, in this embodiment, the difficulty level rank β ​​is taken into consideration, and the higher the difficulty level rank β, the higher the link cost, so a target route RT1 that avoids the slow driving section is calculated.

[0031] 6 is a flowchart showing an example of processing executed by the calculation unit 16A. The processing shown in this flowchart is started, for example, when the driver inputs a destination via the input unit 14. As shown in FIG. 6, first, in step S1, the calculation unit 16A acquires, from the server device 30, via the communication unit 15, travel information (position information, vehicle speed information) of multiple other vehicles 200 transmitted to the server device 30 within a predetermined period T1. Furthermore, the calculation unit 16A acquires an evaluation value α1 corresponding to each road section leading to the destination. For example, the calculation unit 16A acquires the evaluation value α1 for a predetermined time period or a predetermined day of the week.

[0032] Next, in step S2, the calculation unit 16A calculates the average value Va of the traveling speeds of the multiple other vehicles 200 for each road section based on the traveling information acquired in step S1. For example, the calculation unit 16A calculates the average value Va for the current time period or the current day of the week. Furthermore, the calculation unit 16A subtracts the average value Va from the evaluation value α1 of each road section to calculate an average speed difference ΔV, and sets a difficulty level rank β ​​for each road section so that the greater the average speed difference ΔV, the higher the value. This difficulty level rank β ​​is stored in the memory unit 16B in association with the road map information.

[0033] Next, in step S3, the calculation unit 16A calculates a route to the destination based on the road map information stored in the storage unit 16B. More specifically, the calculation unit 16A calculates a route with the smallest link cost, that is, a road that includes a road section with a small difficulty rank β, as the target route.

[0034] Next, in step S4, the calculation unit 16A outputs information about the target route to the monitor 17 and ends the process. As a result, the target route RT1 is displayed on the monitor 17. As shown in FIG. 5, if the target route RT1 is not the shortest route to the destination, information about the difficulty level rank β ​​may also be displayed on the monitor 17. This allows the driver to recognize the reason why the route was selected as the target route RT1.

[0035] The target route RT1 is confirmed when the driver approves the displayed route via the input unit 14. If the driver does not approve the displayed route as the target route RT1, the processing of step S3 is repeated. In this case, the calculation unit 16A calculates the route with the next smallest link cost as the target route RT1 and outputs it to the monitor 17. Note that it is also possible to simultaneously calculate multiple routes that are candidates for the target route RT1 and display the multiple routes on the monitor 17.

[0036] The operation of the route search device according to this embodiment will be described in more detail. Hereinafter, it is assumed that an evaluation value α1 for a predetermined time period (for example, a morning time period) is set for the road section in Fig. 1. In this state, when a driver drives his / her vehicle 100 to a destination, for example, during the daytime, if an obstacle 201 is present on the road RD1 as shown in Fig. 1, the average travel speed Va for the daytime period obtained from travel information of other vehicles 200 within a predetermined period T1 will be small. Therefore, the average speed difference ΔV will be, for example, ΔV1 in Fig. 4, and the difficulty level rank β ​​will be high.

[0037] As a result, the link cost of the road section increases, and a route that does not pass through the road section is set as the target route RT1 (FIG. 5). This causes the vehicle 100 to preferentially travel on roads with lower road difficulty. As a result, the driver (e.g., the driver of a rental vehicle) will drive on road RD1 with many obstacles 201 less frequently, and the driver will be able to drive the vehicle 100 efficiently and safely to the destination.

[0038] On the other hand, when the driver drives the vehicle 101 to the destination at night, if there are no obstacles 201 on the road RD1 at night, the average value Va of the traveling speed obtained from the traveling information of the other vehicle 200 within the predetermined period T1 becomes large. Therefore, the average speed difference ΔV becomes, for example, ΔV2 in FIG. 4, and the difficulty rank β ​​becomes low. As a result, if the road section is included in the shortest route (FIG. 5), the route including the road section is set as the target route RT2 (FIG. 5). This allows the driver to drive the vehicle 100 efficiently to the destination.

[0039] According to this embodiment, the following effects can be achieved. (1) The route search device 11 includes an information acquisition unit 161 that acquires travel information including information on the travel positions and travel speeds of multiple other vehicles 200, a setting unit 162 that calculates an average travel speed Va of the multiple other vehicles 200 for each road section based on the travel information acquired by the information acquisition unit 161 and sets a difficulty level rank β ​​for each road section based on the average travel speed Va, a storage unit 16B that stores road map information including the difficulty level rank β ​​set by the setting unit 162, and a route calculation unit 163 that calculates a target route to a destination that reduces the proportion of travel on roads with a high difficulty level rank β ​​stored in the storage unit 16B (for example, minimizes link cost) (FIG. 3). The setting unit 162 sets the difficulty level rank β ​​so that the greater the difference between the average travel speed Va and a predetermined reference value (evaluation value α1) (average speed difference ΔV) is, the higher the difficulty level rank β ​​becomes (FIG. 4).

[0040] As a result, roads on which there are many obstacles 201 during a predetermined time period (for example, daytime) are likely to be excluded from the target route when the vehicle 100 travels during that time period. As a result, the driver will preferentially travel on roads including road sections with fewer obstacles 201, and can drive the vehicle 100 to the destination efficiently and safely. In other words, according to this embodiment, it is possible to search for a route to the destination that is preferable for the driver.

[0041] (2) The evaluation value α1 is the average value Va of the driving speeds of the multiple other vehicles 200 for each road section in a predetermined time period (first time period). The setting unit 162 sets the difficulty level rank β ​​for each road section based on the average value Va of the driving speeds of the multiple other vehicles 200 in a time period (second time period) different from the predetermined time period. This allows the target route to be set taking into consideration the fact that the difficulty level of driving may differ depending on the time period even on the same road, making it possible to set an optimal target route for the driver.

[0042] (3) The evaluation value α1 may be an average value Va of the driving speeds of the other vehicles 200 for each road section on a predetermined day of the week (first day of the week). In this case, the setting unit 162 sets the difficulty level rank β ​​for each road section based on the average value Va of the driving speeds of the other vehicles 200 on a day of the week (second day of the week) different from the predetermined day of the week. This allows the target route to be set taking into consideration the fact that the difficulty level of driving may differ depending on the day of the week even on the same road, making it possible to set an optimal target route for the driver.

[0043] (4) The road map information stored in the memory unit 16B includes information on the legal speed limit for each road section. The evaluation value α1 may be the legal speed limit for each road section stored in the memory unit 16B. In this case, the setting unit 162 sets the difficulty level rank β ​​for each road section according to the difference between the legal speed limit and the average value Va. In other words, the difficulty level rank β ​​is set higher the greater the difference. The average value Va is the average value of the vehicle speeds of multiple other vehicles 200 within a predetermined period T1 corresponding to, for example, the current time zone or day of the week. This makes it possible to determine the difficulty level of driving for each road section taking into account the difference from the legal speed limit, and to set an optimal target route for the driver.

[0044] (5) The multiple other vehicles 200 include multiple rental vehicles and multiple non-rented vehicles other than the rental vehicles. The evaluation value α1 may be the average value Va of the driving speeds of the multiple non-rented vehicles for each road section. In this case, the setting unit 162 sets the difficulty rank β ​​for each road section based on the average value Va of the driving speeds of the rental vehicles among the multiple other vehicles 200. As a result, when the driver drives the rental vehicle, roads with low difficulty are preferentially set as the target route, making it possible to set a good target route for the driver.

[0045] (6) The road map information stored in the memory unit 16B includes information on the link cost for each road section, which is set so that the link cost increases as the difficulty level rank β ​​increases. This allows the optimum target route to be set in consideration of the difficulty level rank β ​​when setting a target route based on the link cost.

[0046] (7) The other vehicles 200 each have a positioning sensor 12 that detects the positions of the other vehicles 200. The setting unit 162 calculates an average value Va for each road section based on the changes in the positions of the other vehicles 200 detected by the positioning sensor 12. This allows the average value Va to be calculated with high accuracy, and the difficulty level rank β ​​is highly accurate.

[0047] (8) The other vehicles 200 each have a vehicle speed sensor 13 that detects the vehicle speed of the other vehicles 200. The setting unit 162 calculates an average value Va for each road section based on the traveling speeds of the other vehicles 200 detected by the vehicle speed sensor 13. This allows the average value Va to be calculated with high accuracy, and the difficulty level rank β ​​is highly accurate.

[0048] However, if an obstacle 201 is present in a road section, the driver may determine that the vehicle cannot travel on that road section and change the vehicle's route. FIG. 7 is a diagram showing an example of such a road RD2. As shown in FIG. 7, when vehicle C cannot travel on road RD2 due to obstacle 201, vehicle C may first travel backward (route RT11), return the road it traveled on (route RT12), or travel on another road (route RT13). In this way, when vehicle C cannot travel on road RD2 during a specific time period or on a specific day of the week due to the presence of obstacle 102, the driver may change the route by traveling backward with vehicle C. Alternatively, the driver may change the route by making a U-turn.

[0049] The route search device 11 may set a target route using information that a predetermined course change (a course change involving reverse driving or U-turn driving) has been made during such a predetermined time period or day of the week, more specifically, using the average number of course changes per unit time during the predetermined time period or day of the week. In this case, the route search device 11 may be configured in the same manner as in Fig. 3. However, the method for setting the difficulty level rank β ​​in the setting unit 162 differs from that described above.

[0050] That is, based on the travel information (position information) within a predetermined period T1 acquired by the information acquisition unit 161, the setting unit 162 calculates, for each road section, that a plurality of other vehicles 200 have made a lane change involving reverse travel or a U-turn, and calculates the average number of lane changes Na. Furthermore, the setting unit 162 sets a difficulty level rank β ​​for each road section based on the average value Na. Specifically, the setting unit 162 sets a difficulty level rank β ​​so that the greater the difference between the evaluation value α1 and the average number of lane changes Na, the higher the difficulty level rank β. That is, the difficulty level rank β ​​is set based on the characteristic obtained by subtracting the evaluation value α1 from the average number Na to calculate the average number difference ΔN, and replacing the horizontal axis of FIG. 4 with the average number difference ΔN. With this configuration, the driver will preferentially travel on roads including road sections with fewer obstacles 201, enabling the driver to drive the vehicle 100 to the destination efficiently and safely.

[0051] In this case, the evaluation value α1 is the average value of the number of lane changes made by the multiple other vehicles 200 for each road section in a predetermined time period (first time period). Therefore, the setting unit 162 sets the difficulty level rank β ​​for each road section based on the average value Na of the number of lane changes made by the multiple other vehicles 200 in a time period (second time period) different from the above-mentioned predetermined time period. This allows the target route to be set taking into consideration the fact that the difficulty of driving on the same road may differ depending on the time period, making it possible to set an optimal target route for the driver.

[0052] The evaluation value α1 may be the average value of the number of lane changes made by the multiple other vehicles 200 for each road section on a predetermined day of the week (first day of the week). In this case, the setting unit 162 sets the difficulty level rank β ​​for each road section based on the average value Na of the number of lane changes made by the multiple other vehicles 200 on a day of the week (second day of the week) different from the predetermined day of the week. This allows the target route to be set taking into consideration the fact that the difficulty of driving on the same road may differ depending on the day of the week, making it possible to set an optimal target route for the driver.

[0053] The evaluation value α1 may be the average value Na of the number of lane changes of multiple non-rented vehicles for each road section. In this case, the setting unit 162 sets the difficulty rank β ​​for each road section based on the average value Na of the number of lane changes of rented vehicles among the multiple other vehicles 200. As a result, when the driver drives the rented vehicle, roads with low difficulty are preferentially set as the target route, making it possible to set a good target route for the driver.

[0054] Even when the difficulty level rank β ​​is set according to the number of course changes, the road map information stored in the storage unit 16B includes information on the link cost for each road section, which is set so that the link cost increases as the difficulty level rank β ​​increases. This makes it possible to set an optimal target route in consideration of the difficulty level rank β ​​when setting a target route according to the link cost.

[0055] In the above embodiment, the information acquisition unit 161 (travel information acquisition unit) acquires travel information including information on the travel positions and travel speeds of multiple other vehicles 200, but the travel information acquisition unit may acquire travel information including information on the travel positions or travel speeds, and the configuration of the travel information acquisition unit is not limited to the above. In the above embodiment, based on the travel information acquired by the information acquisition unit 161, the setting unit 162 (difficulty level setting unit) calculates an average value Va of the travel speeds of multiple other vehicles 200 for each road section, or calculates an average value Na of the number of lane changes involving reverse travel or U-turn travel, and sets a difficulty level rank β ​​for each road section based on the average value Va or Na, but the configuration of the difficulty level setting unit is not limited to the above.

[0056] In the above embodiment, the controller 16 sets the difficulty level rank β. However, the server device 30 may set the difficulty level rank, and the controller 16 may receive information about the difficulty level. That is, the difficulty level setting unit may be configured by the server device 30. In the above embodiment, the server device 30 sets the evaluation value α1 as a predetermined reference value. However, the controller 16 may set the evaluation value α1. In the above embodiment, the route calculation unit 163 calculates a target route that minimizes the link cost. However, the target route may be calculated so as to avoid traveling on road sections whose difficulty level rank β ​​is equal to or greater than a predetermined value. That is, the route calculation unit may have any configuration as long as it calculates a driving route that reduces the proportion of traveling on roads with a high difficulty level rank.

[0057] The above description is merely an example, and the present invention is not limited to the above-described embodiment and modifications as long as the features of the present invention are not impaired. One or more of the above-described embodiment and modifications can be arbitrarily combined, and modifications can also be combined with each other. [Explanation of symbols]

[0058] 11 Route search device, 12 Positioning sensor, 13 Vehicle speed sensor, 15 Communication unit, 16A Calculation unit, 16B Memory unit, 100 Vehicle, 161 Information acquisition unit, 162 Setting unit, 163 Route calculation unit, 200 Other vehicles, Va, Na Average values, α1 Evaluation value, β Difficulty rank

Claims

1. a travel information acquisition unit that acquires travel information including information on the travel positions and / or travel speeds of a plurality of vehicles; a difficulty setting unit that calculates an average value of the driving speeds of the plurality of vehicles for each road section based on the driving information acquired by the driving information acquisition unit, and sets a difficulty level that indicates a driving difficulty for each road section based on the average value; and a storage unit that stores road map information including the difficulty level rank set by the difficulty level setting unit; a route calculation unit that calculates a driving route to a destination such that a proportion of roads with a high degree of difficulty stored in the storage unit is reduced; The route search device is characterized in that the difficulty level setting unit sets the difficulty level so that the greater the difference between the average value and a predetermined reference value, the higher the difficulty level becomes.

2. 2. The route search device according to claim 1, the predetermined reference value is an average value of the traveling speeds of the plurality of vehicles for each road section in a first time period, The route search device is characterized in that the difficulty setting unit sets the difficulty rank for each road section based on the average value of the driving speeds of the plurality of vehicles in a second time period different from the first time period.

3. 2. The route search device according to claim 1, the predetermined reference value is an average value of the traveling speeds of the plurality of vehicles for each road section on a first day of the week, The difficulty setting unit sets the difficulty rank for each road section based on an average value of the driving speeds of the plurality of vehicles on a second day of the week that is different from the first day of the week.

4. 2. The route search device according to claim 1, The road map information stored in the storage unit includes information on legal speed limits for each road section, the predetermined reference value is a legal speed limit for each road section stored in the storage unit, The difficulty level setting unit sets the difficulty level for each road section in accordance with the difference between the legal speed limit and the average speed.

5. 2. The route search device according to claim 1, The plurality of vehicles includes a plurality of rental vehicles and a plurality of non-rental vehicles other than the rental vehicles, the predetermined reference value is an average value of the traveling speeds of the plurality of non-rented vehicles for each road section, The route search device is characterized in that the difficulty setting unit sets the difficulty rank for each road section based on an average value of the traveling speeds of the plurality of rental vehicles.

6. 6. The route search device according to claim 1, A route search device characterized in that the road map information stored in the memory unit includes information on link costs for each road section that are set to increase as the difficulty level rank increases.

7. 6. The route search device according to claim 1, each of the plurality of vehicles has a positioning sensor for detecting the positions of the plurality of vehicles; The difficulty level setting unit calculates the average value for each road section based on changes in the positions of the plurality of vehicles detected by the positioning sensor.

8. 6. The route search device according to claim 1, Each of the plurality of vehicles has a vehicle speed sensor that detects the traveling speed of the plurality of vehicles, The route search device is characterized in that the difficulty level setting unit calculates the average value for each road section based on the traveling speeds of the plurality of vehicles detected by the vehicle speed sensor.

9. a travel information acquisition unit that acquires travel information including information on the travel positions of a plurality of vehicles; a difficulty setting unit that calculates an average value of the number of lane changes involving reverse driving or U-turn driving of the plurality of vehicles for each road section based on the driving information acquired by the driving information acquisition unit, and sets a difficulty level that indicates the driving difficulty for each road section based on the average value; a storage unit that stores road map information including the difficulty level rank set by the difficulty level setting unit; a route calculation unit that calculates a driving route to a destination such that a proportion of roads with a high degree of difficulty stored in the storage unit is reduced, The route search device is characterized in that the difficulty level setting unit sets the difficulty level so that the greater the difference between the average value and a predetermined reference value, the higher the difficulty level becomes.

10. 10. The route search device according to claim 9, the predetermined reference value is an average value of the number of lane changes of the plurality of vehicles for each road section in a first time period, The difficulty setting unit sets the difficulty rank for each road section based on the average number of lane changes made by the plurality of vehicles during a second time period that is different from the first time period.

11. 10. The route search device according to claim 9, the predetermined reference value is an average value of the number of lane changes of the plurality of vehicles for each road section on a first day of the week, The difficulty setting unit sets the difficulty rank for each road section based on the average number of lane changes made by the plurality of vehicles on a second day of the week that is different from the first day of the week.

12. 10. The route search device according to claim 9, The plurality of vehicles includes a plurality of rental vehicles and a plurality of non-rental vehicles other than the rental vehicles, the predetermined reference value is an average value of the number of lane changes of the plurality of non-rented vehicles for each road section, The route search device is characterized in that the difficulty setting unit sets the difficulty rank for each road section based on the average number of route changes made by the multiple rental vehicles.

13. 13. The route search device according to claim 9, A route search device characterized in that the road map information stored in the memory unit includes information on link costs for each road section that are set to increase as the difficulty level rank increases.

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