Route misconversion detection device and route misconversion detection method for route misconversion detection device

Abstract

To properly determine whether erroneous route transformation has been made in the event that a set route in a navigation map is transformed into an actual use route in a high-precision map.SOLUTION: An erroneous route transformation determination system determines whether erroneous route transformation has been made in the event that a set route in a navigation map for a navigation system of a vehicle is transformed into an actual use route in a high-precision map. Position information on an intersection on the set route and an advance angle at the intersection on the set route are extracted based on the navigation map and set route. Position information on an intersection on an actual use route and an advance angle at the intersection on the actual use route are extracted based on the high-precision map and actual use route. Whether erroneous route transformation has been made is determined based on an advance angle on the set route at a common intersection, which is an intersection common between the set route and actual use route, and an advance angle on the actual use route.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a route erroneous conversion determination device and a route erroneous conversion determination method for the route erroneous conversion determination device. [Background Art]

[0002] Conventionally, Japanese Unexamined Patent Application Publication No. 2017-215653 is known as a technical document related to a route erroneous conversion determination device. This publication discloses that, in an automatic driving system that acquires branch point information in an automatic driving section searched by a navigation device outside a vehicle, whether automatic driving is enabled or disabled is determined depending on whether the searched branch point matches detailed map data stored in the vehicle. [Prior Art Documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Unexamined Patent Application Publication No. 2017-215653 [Summary of the Invention] [Problem to be Solved by the Invention]

[0004] It is known that erroneous route conversion may occur when converting a route on a navigation map for a navigation system into a route on a high-precision map used for automatic driving, driving assistance, or the like. Problems occur if automatic driving or driving assistance is executed in a state where an erroneous route conversion has occurred, so there is a need for a technology that appropriately determines the presence or absence of erroneous conversion. [Means for Solving the Problem]

[0005] One aspect of the present invention is a route misconversion determination device for determining whether or not a route misconversion occurs when a set route on a navigation map for a vehicle's navigation system is converted to a practical route on a high-precision map. The device extracts location information of intersections on the set route and the angle of travel at intersections on the set route based on the navigation map and the set route, extracts location information of intersections on the practical route and the angle of travel at intersections on the practical route based on the high-precision map and the practical route, and determines whether or not a route misconversion occurs based on the angle of travel on the set route and the angle of travel on the practical route at common intersections which are intersections common to the set route and the practical route.

[0006] According to one aspect of the present invention, a route misconversion determination device can appropriately determine whether or not a route misconversion occurs when converting from a set route on a navigation map to a practical route on a high-precision map, by focusing on intersections where route misconversion is likely to occur and determining whether or not a route misconversion has occurred from the angle of travel at intersections common to the set route and the practical route.

[0007] In the above-described route misconversion determination device, it may determine whether a vehicle traveling along the set route proceeds straight through a common intersection based on the direction of travel of the set route at the common intersection, and whether a vehicle traveling along the practical route proceeds straight through a common intersection based on the direction of travel of the practical route at the common intersection. If the determination result of the direction of travel at the common intersection in the set route and the determination result of the direction of travel at the common intersection in the practical route do not match, it may be determined that a route misconversion has occurred. This route misconversion detection device can appropriately determine, based on the angle of travel at common intersections, whether a route misconversion has occurred due to a mismatch in the direction of travel at common intersections between the set route and the actual route.

[0008] In the above-described route misconversion detection device, if, among the multiple road links extending from a common intersection, the road link whose angle with respect to the entry link of the set route is closest to 180° is not the exit link of the set route, it may be determined that a vehicle traveling along the set route will not go straight through the common intersection. Alternatively, if, among the multiple road links extending from a common intersection, the road link whose angle with respect to the entry link of the practical route is closest to 180° is not the exit link of the practical route, it may be determined that a vehicle traveling along the practical route will not go straight through the common intersection. According to this route mistranslation detection device, since the road link located directly in front of the entry link is highly likely to be the destination if the vehicle proceeds straight through the intersection, if there is a road link located directly in front of the entry link compared to the exit link, it can appropriately determine that a vehicle traveling along that route will not proceed straight through the common intersection.

[0009] In the route misconversion detection device described above, the road type of roads on the set route may be extracted based on the navigation map and the set route, and the road type of roads on the actual route may be extracted based on the high-precision map and the actual route, and the presence or absence of route misconversion may be determined based on the road type of roads on the set route and the road type of roads on the actual route. This route misconversion detection device can appropriately determine whether or not a route misconversion has occurred by comparing the road type on the set route with the road type on the actual route.

[0010] In the above-described route misconversion determination device, it may determine whether a vehicle traveling along the set route proceeds straight through a common intersection based on the road type of the set route before and after the common intersection, and also determine whether a vehicle traveling along the practical route proceeds straight through a common intersection based on the road type of the practical route before and after the common intersection. If the determination result of the direction of travel at the common intersection on the set route does not match the determination result of the direction of travel at the common intersection on the practical route, it may be determined that a route misconversion has occurred. This route misconversion detection device can appropriately determine whether a route misconversion has occurred due to a mismatch in the direction of travel at a common intersection between the set route and the actual route, based on the road types before and after the common intersection.

[0011] In the above-described route misconversion detection device, if the road type of the entry link of the set route at a common intersection does not match the road type of the exit link of the set route, it may be determined that a vehicle traveling along the set route will not go straight through the common intersection. Similarly, if the road type of the entry link of the practical route at a common intersection does not match the road type of the exit link of the practical route, it may be determined that a vehicle traveling along the practical route will not go straight through the common intersection. According to this route mistranslation detection device, when proceeding straight through a common intersection, the road type (such as a general road or an expressway) is considered to match between the entry link and the exit link. Therefore, if the road type of the entry link and the road type of the exit link do not match, it can be appropriately determined that the route does not proceed straight through the common intersection.

[0012] Another aspect of the present invention is a method for determining whether a route conversion is incorrect when a set route on a navigation map for a vehicle's navigation system is converted to a practical route on a high-precision map, wherein the route conversion determination device extracts location information of intersections on the set route and the angle of travel at intersections on the set route based on the navigation map and the set route, the route conversion determination device extracts location information of intersections on the practical route and the angle of travel at intersections on the practical route based on the high-precision map and the practical route, and the route conversion determination device determines whether a route conversion is incorrect based on the angle of travel on the set route and the angle of travel on the practical route at a common intersection which is an intersection common to the set route and the practical route.

[0013] According to another aspect of the present invention, a route misconversion determination method focuses on intersections where route misconversion is likely to occur and determines whether or not a route misconversion has occurred from the angle of travel at intersections common to the set route and the practical route, thereby appropriately determining whether or not a route misconversion has occurred when converting from the set route on the navigation map to the practical route on the high-precision map. [Effects of the Invention]

[0014] According to each aspect of the present invention, it is possible to appropriately determine whether there is an erroneous route conversion when a set route on a navigation map is converted to a practical route on a high-precision map. [BRIEF DESCRIPTION OF THE DRAWINGS]

[0015] [Figure 1] It is a block diagram showing a route generation device (erroneous route conversion determination device) according to a first embodiment. [Figure 2] It is a diagram showing an example of a set route set on a navigation map. [Figure 3] (a) It is a diagram for explaining an example of a traveling angle at an intersection of a set route. (b) It is a diagram for explaining an example of a practical route in which an erroneous route conversion has occurred. [Figure 4] It is a flowchart showing an example of common intersection identification processing. [Figure 5] It is a flowchart showing an example of traveling direction determination processing for a set route. [Figure 6] It is a flowchart showing another example of traveling direction determination processing for a set route. [Figure 7] It is a flowchart showing an example of erroneous route conversion determination processing. [Figure 8] It is a block diagram showing a route generation device (erroneous route conversion determination device) according to a second embodiment. [Figure 9] It is a flowchart showing another example of erroneous route conversion determination processing according to the second embodiment. [MODE FOR CARRYING OUT THE INVENTION]

[0016] Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0017] [First Embodiment] FIG. 1 is a block diagram showing a route generation device (route erroneous conversion determination device) 10 according to a first embodiment. The route generation device 10 shown in FIG. 1 is a device that converts a set route on a navigation map generated by a vehicle navigation system 1 into a practical route on a high-precision map. In order to execute automatic driving or driving assistance according to the set route on the navigation map, conversion to a practical route on a high-precision map is necessary.

[0018] A navigation map is a map used by the navigation system 1 to guide the driver of the vehicle. A set route is a route for guiding the vehicle from the start point to the destination on the navigation map. A high-precision map is a map with higher accuracy than a navigation map, and is map information with accuracy that can be used for automatic driving or driving assistance. A practical route is a route on a high-precision map that can be used for automatic driving or driving assistance of a vehicle. The practical route corresponds to a decoding result obtained by converting the set route on the navigation map onto the high-precision map.

[0019] In conversion from the set route on the navigation map to the practical route on the high-precision map, erroneous conversion occurs due to differences in conversion accuracy, differences in map freshness (for example, time differences in map update frequency, differences in specifications of map manufacturers, and the like. If erroneous conversion occurs, there is a risk that the vehicle may enter or be guided to an incorrect route during automatic driving or driving assistance. For this reason, the route generation device 10 determines whether route erroneous conversion has occurred by comparing the set route and the practical route. That is, the route generation device 10 functions as a route erroneous conversion determination device.

[0020] The route generation device 10 according to the present embodiment is connected to the navigation system 1. The vehicle is not particularly limited as long as it travels on roads. The vehicle may be a four-wheeled vehicle, a two-wheeled vehicle, or a personal mobility vehicle. The vehicle has an automatic driving or driving assistance function. Automatic driving is vehicle control that causes the vehicle to automatically travel toward a destination without any driving operation by the driver of the vehicle. Driving assistance is vehicle control that assists the driving of the vehicle driver. Driving assistance includes advanced driving assistance that assists the vehicle's driving so as to travel along a practical route.

[0021] Navigation system 1 is a system that guides the driver of the vehicle to a pre-set destination. The destination is set by the vehicle's occupants. Navigation system 1 is connected to a GNSS (Global Navigation Satellite System) receiver 2, an HMI (Human Machine Interface) 3, and a navigation map database 4.

[0022] The GNSS receiver 2 measures the vehicle's position (e.g., the vehicle's latitude and longitude) by receiving signals from positioning satellites. The GNSS receiver 2 may also be a GPS (Global Positioning System) receiver. The GNSS receiver 2 transmits the measured vehicle position information to the navigation system 1.

[0023] HMI3 is an interface for inputting and outputting information between the navigation system 1 and the driver. HMI3 includes, for example, a display, speaker, indicator, and operation buttons located inside the vehicle. HMI3 may also have a touch panel display or a HUD (Head-Up Display). HMI3 allows the driver to set the vehicle's destination by transmitting driver input information to the navigation system 1. HMI3 displays guidance information to the destination on the in-vehicle display in response to signals from the navigation system 1. HMI3 may also provide voice guidance.

[0024] The navigation map database 4 is a database that stores navigation maps used to guide the vehicle driver. The navigation map includes nodes corresponding to intersections and junctions, and road links connecting those nodes. The navigation map is road network data consisting of nodes, road links, and various information associated with them. The navigation map corresponds to an SD [Standard] map, which has less information than the high-precision map described later. The navigation map database 4 does not necessarily need to be installed in the vehicle; it may be created on a server that can communicate with the vehicle.

[0025] The navigation system 1 recognizes the vehicle's current position on the navigation map based on the vehicle's position information measured by the vehicle's GNSS receiver 2 and the navigation map in the navigation map database 4. Based on the vehicle's current position, destination, and navigation map, the navigation system 1 searches for a set route (guided route) for the vehicle to reach its destination. Well-known methods can be used for route searching. The navigation system 1 performs guidance on the set route via the HMI 3 in response to the driver's request. Note that the set route does not necessarily have to be used for driver guidance and may be used only for route conversion as described later.

[0026] Here, Figure 2 shows an example of a set route configured on the navigation map. In Figure 2, road links included in the set route are shown as solid lines, and road links not included in the set route are shown as dashed lines. Figure 2 shows the starting point (starting point of the set route) 50 and the destination 51. Also in Figure 2, the road link 50a extending from the starting point 50, the first node 60, two road links 60a, 60b extending from the first node 60, the second node 61, two road links 61a, 61b extending from the second node 61, the third node 62, two road links 62a, 62b extending from the third node 62, the fourth node 63, and two road links 63a, 63b extending from the fourth node 63.

[0027] In Figure 2, the first node 60, the second node 61, the third node 62, and the fourth node 63 correspond to intersections or junctions on the set route. The road link 50a extending from the starting point 50 corresponds to the entry link on the set route through which a vehicle enters the first node 60. Road link 60a is the road link that a vehicle travels when it proceeds straight through the first node 60. Road link 60b is the road link that a vehicle travels when it turns left and branches off from the first node 60.

[0028] As shown in Figure 2, the configured path proceeds towards the second node 61 by passing through a road link 60a that goes straight from the first node 60. Road link 60a is an exit link on the configured path through which a vehicle exits the first node 60, and is also an entry link through which a vehicle enters the second node 61.

[0029] At the second node 61, road link 61a is the road link when an entering vehicle turns left at the second node 61 and branches off. Road link 61b is the road link when an entering vehicle proceeds straight through the second node 61. The set route proceeds towards the third node 62 by turning left at the second node 61 and passing through road link 61a. Road link 61a is both an exit link for the vehicle to exit the second node 61 on the set route and an entry link for the vehicle to enter the third node 62. Navigation system 1 provides guidance to the vehicle to proceed diagonally to the left (road link 61a) at the second node 61.

[0030] At the third node 62, road link 62a is the road link when an incoming vehicle turns left at the third node 62 and branches off. Road link 62b is the road link when an incoming vehicle turns right at the third node 62 and branches off. The third node 62 is a T-junction, and road links 62a and 63a are arranged in a straight line. The set route proceeds towards the fourth node 63 by turning left at the third node 62 and passing through road link 62a. Road link 62a is both an exit link for a vehicle to exit the third node 62 on the set route and an entry link for a vehicle to enter the fourth node 63. Navigation system 1 provides guidance to the vehicle to proceed to the left (road link 62a) at the third node 62.

[0031] At the fourth node 63, road link 63a is the road link when an incoming vehicle turns left at the fourth node 63 and branches off. Road link 63b is the road link when an incoming vehicle turns right at the fourth node 63 and branches off. The fourth node 63 is a Y-junction, and road links 63a and 63b are arranged in a Y-shape. The set route proceeds towards the destination 51 by turning left at the fourth node 63 and passing through road link 63a. Road link 63a is the exit link when a vehicle exits the fourth node 63 on the set route. Navigation system 1 provides guidance to the vehicle to proceed diagonally to the left (road link 63a) at the fourth node 63.

[0032] The route generation device 10 converts a set route on the navigation map set by the navigation system 1 into a practical route on a high-precision map. The route generation device 10 may be configured as part of an automated driving system or a driver assistance system. The route generation device 10 also functions as a route misconversion detection device that determines whether or not a route misconversion has occurred.

[0033] The route generation device 10 includes an ECU (Electronic Control Unit), which is not shown in the diagram. The ECU is an electronic control unit having a CPU (Central Processing Unit) and a memory unit such as ROM (Read Only Memory) or RAM (Random Access Memory). The route generation device 10 performs various calculation processes, which will be described later, using the ECU.

[0034] The route generation device 10 is connected to the high-precision map database 5 and the vehicle control device 6. The high-precision map database 5 is a database that stores high-precision maps.

[0035] The high-precision map is an HD (High Definition) map with a precision suitable for autonomous driving or driver assistance. The high-precision map contains more detailed information than a navigation map. The high-precision map may have separate road links for each lane, and may register nodes not only for intersections and junctions, but also for points where the road shape (e.g., lane width) changes. In the high-precision map, multiple nodes corresponding to entry and exit points may be set for a single intersection. The high-precision map may be configured with a precision capable of performing autonomous driving at Level 3 or higher as defined by the SAE (Society of Automotive Engineers) in the United States. The high-precision map database 5 does not necessarily need to be installed in the vehicle; it may be formed on a server that can communicate with the vehicle.

[0036] The vehicle control device 6 is a device that controls the movement of the vehicle. The vehicle control device 6 may be part of the vehicle's automated driving system or driver assistance system. The vehicle control device 6 performs vehicle control based on the practical route generated by the route generation device 10. The vehicle control device 6 may perform automated driving, which automatically drives the vehicle to its destination along the practical route. The vehicle control device 6 may perform advanced driver assistance, which assists with branching, merging, lane changes, right and left turns, etc., along the practical route.

[0037] The vehicle control device 6 controls the vehicle's movement by, for example, controlling the vehicle's drive actuator, brake actuator, and steering actuator. The drive actuator controls the amount of air supplied to the engine (throttle opening) in response to a control signal from the vehicle control device 6, thereby controlling the vehicle's driving force. If the vehicle is a hybrid electric vehicle (HEV), in addition to the amount of air supplied to the engine, a control signal from the vehicle control device 6 is input to the motor as a power source to control its driving force. If the vehicle is a battery electric vehicle (BEV), a control signal from the vehicle control device 6 is input to the motor as a power source to control its driving force. The brake actuator controls the brake system in response to a control signal from the vehicle control device 6, thereby controlling the braking force applied to the vehicle's wheels. The steering actuator controls the drive of the assist motor that controls the steering torque in the electric power steering system in response to a control signal from the vehicle control device 6.

[0038] Next, the functional configuration of the route generation device 10 will be described. The route generation device 10 includes a route conversion unit 11, a set route information extraction unit 12, a practical route information extraction unit 13, and a route misconversion determination unit 14.

[0039] The route conversion unit 11 converts the set route on the vehicle's navigation map into a practical route on a high-precision map. The route conversion unit 11 converts the set route into a practical route using a well-known route conversion method. Examples of route conversion methods include the DLR method [Dynamic Location Referencing] and the Pre-Coded method [Pre-Coded Location Referencing]. In the DLR method, it is known that the agreement rate between the position on the navigation map and the position on the high-precision map decreases depending on the differences between the maps. In the Pre-Coded method as well, when the road structure changes, such as when link IDs are assigned to new roads or when intersections are rebuilt, there is a risk of route conversion errors occurring due to the time difference in the update timing between the navigation map and the high-precision map. Thus, the possibility of route conversion errors exists in both methods.

[0040] The set route information extraction unit 12 extracts set route information, which is information related to the set route, based on the navigation map in the navigation map database 4 and the set route set by the navigation system 1. The set route information includes, for example, the location information of intersections on the set route and the angle of travel at intersections on the set route. The set route information may also include the number of road links for each intersection. In addition to intersections, the unit may also extract location information and angles of travel at branching points.

[0041] The location information of intersections on the set route may be latitude and longitude on the navigation map, or it may be relative coordinate information based on the starting point of vehicle guidance on the navigation map (for example, the starting point of the set route). As the location information of intersections on the set route, the distance traveled or the travel ratio on the set route based on the current vehicle's position may be used. The travel ratio is the ratio of the distance from the current vehicle's position to the intersection on the set route to the total distance from the current vehicle's position to the destination on the set route. In this case, the starting point of the set route may be used instead of the current vehicle's position.

[0042] The angle of travel at an intersection on the set route corresponds to the angle formed by the entry link and exit link of the set route to that intersection. The entry link is the road link on the navigation map that corresponds to the road when a vehicle traveling along the set route enters the intersection. The exit link is the road link on the navigation map that corresponds to the road when a vehicle traveling along the set route exits the intersection.

[0043] Here, Figure 3(a) is a diagram illustrating an example of the travel angle at an intersection of the set path. Figure 3(a) shows the travel angle α of the set path at the second node 61 shown in Figure 2. As shown in Figure 3(a), the travel angle α of the set path at the second node 61 can be determined as the angle between the road link 60a, which is the entry link on the set path to the second node 61, and the road link 61a, which is the exit link on the set path to the second node 61.

[0044] The format of the direction of travel data is not particularly limited. The direction of travel may be expressed as the direction of travel of the vehicle at an intersection (information consisting only of right turn, left turn, or going straight). The direction of travel may be expressed using any angle unit obtained by dividing the circumference into equal parts (e.g., 16 divisions) of a predetermined value. The direction of travel may be expressed using the angle relative to the center of an arc obtained by dividing the circumference into 360 equal parts (so-called arc degree). The set route information may also include the angle that each road link connected to each intersection on the set route makes with the entry link.

[0045] The set route information may include road information for roads along the set route. Road information is included in the navigation map. Road information includes road types such as expressways and general roads. In road types, connecting roads from general roads to expressways may be distinguished, and exit roads from expressways to general roads may be distinguished. Road types may include national roads and major local roads, and may also include distinctions as toll roads or not.

[0046] The road information may include at least one of the following: road width, number of road lanes, road name, and road number. The set route information extraction unit 12 extracts road information for entry links and road information for exit links at intersections on the set route. The set route information may also include guidance information from the navigation system 1. Furthermore, the set route information may include road information for each road link connected to each intersection on the set route.

[0047] The practical route information extraction unit 13 extracts practical route information, which is information related to the practical route, based on the high-precision map in the high-precision map database 5 and the practical route generated by the route conversion unit 11. The practical route information includes, for example, the location information of intersections on the practical route and the angle of travel at the intersections on the practical route. If an intersection consists of multiple nodes, the practical route information extraction unit 13 extracts it as an intersection separately from the node. The practical route information may also include the number of branches at the intersection. The number of branches is counted per road, not per lane, for comparison with the navigation map. For the sake of simplicity, the terms node and road link are also used in the high-precision map.

[0048] The location information of intersections on the practical route is extracted in a format that can be compared with the location information of intersections on the set route. For example, if the high-precision map includes the location information of the center of the intersection, the location information of the center of the intersection is used. If the high-precision map only includes the location information of nodes set as the entry and exit points of the intersection, the intermediate coordinates of each node corresponding to the intersection may be used as the location information of the intersection. The location information of intersections on the practical route may be latitude and longitude on the high-precision map, or it may be relative coordinate information based on the vehicle guidance starting point (e.g., the starting point of the practical route) on the high-precision map. The distance traveled or the distance traveled on the practical route relative to the current vehicle position may be used as the location information of intersections on the practical route. In this case, the starting point of the practical route may be used instead of the current vehicle position.

[0049] The angle of travel at intersections on the practical route is also extracted in a format that allows for comparison with the angle of travel at intersections on the set route. The angle of travel at intersections on the practical route may contain more detailed information than the angle of travel at intersections on the set route.

[0050] The angle of travel at an intersection on a practical route corresponds to the angle formed by the entry and exit links of the practical route to that intersection. The entry and exit links on a practical route may be treated on a lane basis, or they may be treated as road units that combine multiple adjacent lanes.

[0051] Figure 3(b) is a diagram illustrating an example of a practical route where route conversion errors occurred. For ease of explanation, the practical route on the high-precision map is represented using nodes and road links equivalent to those on the navigation map. In Figure 3(b), it is assumed that road link 61b, not road link 61a, is recognized as the exit link on the practical route due to the route conversion errors. In Figure 3(b), road links included in the practical route are shown as solid lines, and road links not included in the practical route are shown as dashed lines.

[0052] The practical route information extraction unit 13 extracts the travel angle β (approximately 180°) formed by the entry link 60a and the exit link 61b as the travel angle at the second node 61 shown in Figure 3(b). The format of the travel angle data at intersections in the practical route is not particularly limited as long as it is comparable to the travel angle at intersections in the set route.

[0053] The practical route information may include road information for roads along the practical route. The road information is included in the high-precision map. The road information for roads along the practical route is also extracted in a format that can be compared with the road information for intersections on the set route. The road information may include at least one of the following: road width, number of lanes, road name, and road number. The road information for the practical route may be more detailed than the road information for the set route. The practical route information extraction unit 13 distinguishes and extracts road information for entry links and exit links at intersections on the practical route.

[0054] The route misconversion determination unit 14 determines whether or not a route misconversion has occurred by the route conversion unit 11, based on the set route information extracted by the set route information extraction unit 12 and the practical route information extracted by the practical route information extraction unit 13. The route misconversion determination unit 14 performs the route misconversion determination using, for example, a common intersection which is an intersection common to both the set route and the practical route.

[0055] The route misconversion determination unit 14 identifies common intersections based, for example, on the location information of intersections on the set route and the location information of intersections on the actual route. Normally, all intersections on the set route become common intersections that are also on the actual route. The route misconversion determination unit 14 identifies intersections as common intersections if their location information, such as latitude and longitude, matches.

[0056] The route misconversion determination unit 14 may or may not require a perfect match of intersection location information when identifying common intersections. The route misconversion determination unit 14 may identify an intersection as a common intersection if there is an intersection on the practical route whose distance from the location of the intersection on the set route is less than the intersection determination threshold. The value of the intersection determination threshold is not particularly limited, but can be set taking into account the difference in accuracy between the navigation map and the high-precision map.

[0057] Furthermore, the route misconversion determination unit 14 may, in addition to determining the location information of intersections, extract intersections as common intersections when the number of branching points matches between the set route and the actual route. The number of branching points is the number of roads branching off from the intersection. In addition, the route misconversion determination unit 14 may use common branching points instead of common intersections in the following processes. The route misconversion determination unit 14 may also use both common intersections and common branching points.

[0058] The route misconversion determination unit 14 determines whether or not a route misconversion has occurred at each common intersection, for example, by using the angle of travel at the common intersection and road information. The route misconversion determination unit 14 determines, for example, whether a vehicle traveling along the set route will go straight through the common intersection based on the angle of travel of the set route at the common intersection. Going straight means that the vehicle continues straight along the road it is traveling on without turning right or left. Going straight also includes vehicles traveling along a curve or a common branching point that branches in a Y shape continuing straight along the road they are traveling on.

[0059] Specifically, the route misconversion determination unit 14 determines that a vehicle traveling along the set route will not proceed straight through the common intersection if the road link at the common intersection whose angle with respect to the entry link of the set route is closest to 180° is not the exit link of the set route. Generally, the road link located directly in front of the entry link is more likely to be the destination if the vehicle proceeds straight through the intersection. Therefore, if there is a road link located directly in front of the entry link compared to the exit link, it can be assumed that a vehicle traveling along the set route will turn right or left at the common intersection. The route misconversion determination unit 14 may also make the above determination by referring to the navigation map.

[0060] The route misconversion determination unit 14 determines that, at the second node 61 shown in Figure 3(a), the road link 61b whose angle with respect to the entry link 60a is closest to 180° is different from the exit link 61a on the set route, and therefore a vehicle traveling along the set route will not proceed straight through the second node 61 (common intersection).

[0061] Furthermore, the route misconversion determination unit 14 may determine that a vehicle traveling along the set route will not proceed straight through the common intersection if the angle difference (absolute value) between the travel angle of the set route at the common intersection and 180° is greater than or equal to the branching determination threshold. If there is no road link directly in front of the entry link and the road branches in a Y-shape, the unit may determine that a vehicle traveling along the set route will not proceed straight through the common intersection. The value of the branching determination threshold is not particularly limited. The branching determination threshold may be 30°, 45°, 50°, or 60°.

[0062] Furthermore, if the route misconversion determination unit 14 has extracted the direction of travel of the vehicle at the intersection (right turn, left turn, straight ahead, etc.) as information, it can directly determine whether the vehicle will proceed straight through the common intersection based on the direction of travel of the set route at the common intersection.

[0063] The route misconversion determination unit 14 may determine whether a vehicle traveling along the set route will proceed straight through the common intersection based on the road information of the set route before and after the common intersection. For example, the route misconversion determination unit 14 determines whether the road type of the entry link and the road type of the exit link of the set route to the common intersection match. If the road type of the entry link and the road type of the exit link of the set route to the common intersection do not match, the route misconversion determination unit 14 determines that a vehicle traveling along the set route will not proceed straight through the common intersection. Generally, when proceeding straight through an intersection, it can be assumed that the road type of the entry link (e.g., a public road) and the road type of the exit link (e.g., a public road) match.

[0064] The route misconversion determination unit 14 may also determine whether the only road link in the road links of a common intersection that matches the road type of the entry link is the exit link. If the only road link in the road links of a common intersection that matches the road type of the entry link is the exit link, the route misconversion determination unit 14 determines that a vehicle traveling along the set route will proceed straight through the common intersection. This is because, generally, when a vehicle proceeds straight through an intersection and travels on the same road, the road type of the entry link and the road type of the exit link will match. The route misconversion determination unit 14 may also make the above determination by referring to the navigation map.

[0065] The route misconversion determination unit 14 may, similar to the road type, use road information such as road number, road name, and road width to determine whether a vehicle traveling along the set route proceeds straight through a common intersection. Note that road numbers are set and associated on a road basis, not on a lane basis.

[0066] Generally, when a vehicle travels straight through an intersection on the same road, it can be assumed that the road number of the entry link and the road number of the exit link will match, or that the road numbers are assigned according to a certain regularity, such as sequential numbering. Also, if it is the same road, the road name is likely to be the same before and after the intersection. For this reason, the route misconversion determination unit 14 may determine that a vehicle traveling along the set route will go straight through the common intersection if, among the road links of the common intersection, only the exit link matches the road number or road name of the entry link. The road width can also be referenced when determining whether a vehicle is going straight.

[0067] Similarly, the route misconversion determination unit 14 determines, for example, whether a vehicle traveling along the practical route proceeds straight through a common intersection based on the direction of travel of the practical route at the common intersection. The method for determining the direction of travel at a common intersection using the direction of travel can be the same as in the case of a set route.

[0068] The route misconversion determination unit 14 determines that, at the second node 61 shown in Figure 3(b), the road link 61b whose angle with respect to the entry link 60a is closest to 180° coincides with the exit link 61b on the practical route, and therefore determines that a vehicle traveling along the practical route will proceed straight through the second node 61 (common intersection). The route misconversion determination unit 14 may also make the above determination by referring to a high-precision map.

[0069] Furthermore, the route misconversion determination unit 14 may determine whether a vehicle traveling along a practical route proceeds straight through a common intersection based on road information of the practical route before and after the common intersection. The method for determining the direction of travel at a common intersection using road information can be the same as in the case of a set route. The route misconversion determination unit 14 may also perform the above determination by referring to a high-precision map.

[0070] The route misconversion determination unit 14 determines whether or not a route misconversion has occurred based on the determination result of the direction of travel of the set route at the common intersection and the determination result of the direction of travel of the actual route at the common intersection. If the determination result of the direction of travel of the set route at the common intersection and the determination result of the direction of travel of the actual route at the common intersection do not match, the route misconversion determination unit 14 determines that a route misconversion has occurred at that common intersection.

[0071] Specifically, the route misconversion determination unit 14 determines that a route misconversion has occurred at the second node 61 if, as shown in Figure 3(a), it determines that the direction of travel of the set route at the second node 61 is not straight, while, as shown in Figure 3(b), it determines that the direction of travel of the practical route at the second node 61 is straight.

[0072] Furthermore, the route misconversion determination unit 14 may determine the direction of travel at a common intersection not by whether it is going straight or not, but by whether it is going straight, turning right, or turning left. Whether it is a right turn or a left turn can be determined, for example, by the relative magnitude of the travel angle to 180°. In this case, if the route misconversion determination unit 14 determines that the direction of travel of the set route at the common intersection is a left turn, and the direction of travel of the actual route at the common intersection is a right turn, it will determine that a route misconversion has occurred at the common intersection.

[0073] The route misconversion determination unit 14 may determine that no route misconversion has occurred for the entire practical route if it determines that no route misconversion has occurred at any common intersection. The route misconversion determination unit 14 may also narrow down the common intersections to be determined. For example, the route misconversion determination unit 14 may determine whether the direction of travel of the set route and the direction of travel of the practical route match, by only determining common intersections where the direction of travel of the set route is either a left turn or a right turn.

[0074] Next, the route misconversion determination method of the route generation device 10 (route misconversion determination device) according to the first embodiment will be explained with reference to Figures 4 to 7. Figure 4 is a flowchart of an example of common intersection identification processing. This process is executed when the set route is converted to a practical route.

[0075] As shown in Figure 4, the route generation device 10 performs S1 by extracting set route information using the set route information extraction unit 12. The set route information extraction unit 12 extracts set route information based on the navigation map in the navigation map database 4 and the set route set by the navigation system 1. After that, the route generation device 10 proceeds to S2.

[0076] In S2, the route generation device 10 extracts practical route information using the practical route information extraction unit 13. The practical route information extraction unit 13 extracts practical route information based on the high-precision map of the high-precision map database 5 and the practical routes generated by the route conversion unit 11. Note that the order of S1 and S2 may be reversed, or they may be executed simultaneously. After that, the route generation device 10 proceeds to S3.

[0077] In S3, the route generation device 10 identifies common intersections using the route misconversion determination unit 14. The route misconversion determination unit 14 identifies common intersections based on the location information of intersections in the set route and the location information of intersections in the actual route. Common intersections may include common branching points. After that, the route generation device 10 terminates the common intersection identification process.

[0078] Figure 5 is a flowchart showing an example of the process for determining the direction of travel on a set route. The direction of travel determination process is executed when a common intersection is identified in the flowchart shown in Figure 4.

[0079] As shown in Figure 5, in S10, the route generation device 10 uses the route misconversion determination unit 14 to determine whether the road link among the multiple road links at the common intersection that has the angle closest to 180° with respect to the entry link of the set route is the exit link of the set route. If the route generation device 10 determines that the road link closest to 180° is the exit link of the set route (S10: YES), it proceeds to S11. If the route generation device 10 does not determine that the road link closest to 180° is the exit link of the set route (S10: NO), it proceeds to S13.

[0080] In S11, the route generation device 10 uses the route misconversion determination unit 14 to determine whether the angle difference between the setting route's travel angle at a common intersection and 180° is greater than or equal to the branching determination threshold. If the route generation device 10 determines that the angle difference is greater than or equal to the branching determination threshold (S11: YES), it proceeds to S12. If the route generation device 10 does not determine that the angle difference is greater than or equal to the branching determination threshold (S11: NO), it proceeds to S13.

[0081] In S12, the route generation device 10 determines that the vehicle will proceed straight through the common intersection on the set route. After that, the current direction of travel determination process is terminated.

[0082] In S13, the route generation device 10 determines that the vehicle will not proceed straight through the common intersection on the set route. After that, the current direction of travel determination process is terminated.

[0083] Figure 6 is a flowchart showing another example of the process for determining the direction of travel of a set path. The process for determining the direction of travel in Figure 6 may be performed instead of the process for determining the direction of travel in Figure 5, or both processes in Figure 5 and Figure 6 may be performed. If both processes in Figure 5 and Figure 6 are performed, the result of the determination in Figure 6 may take precedence.

[0084] As shown in Figure 6, in S20, the route generation device 10 uses the route misconversion determination unit 14 to determine whether the road type of the entry link and the road type of the exit link of the set route to the common intersection match. If the route generation device 10 determines that the road type of the entry link and the road type of the exit link match (S20: YES), it proceeds to S21. If the route generation device 10 does not determine that the road type of the entry link and the road type of the exit link match (S20: NO), it proceeds to S23.

[0085] In S21, the route generation device 10 uses a route misconversion determination unit 14 to determine whether the only road link in the common intersection that matches the road type of the entry link is the exit link. If the route misconversion determination unit 14 determines that the only road link that matches the road type of the entry link is the exit link (S21: YES), the process proceeds to S22. If the route misconversion determination unit 14 does not determine that the only road link that matches the road type of the entry link is the exit link (S21: NO), the process proceeds to S23.

[0086] In S22, the route generation device 10 determines that the vehicle will proceed straight through the common intersection on the set route. After that, the current direction of travel determination process is terminated.

[0087] In S23, the route generation device 10 determines that the vehicle will not proceed straight through the common intersection on the set route. After that, the current direction of travel determination process is terminated.

[0088] Note that the flowcharts in Figures 5 and 6 are applicable not only to pre-configured routes but also to actual routes. The direction of travel at common intersections on an actual route can be determined by following the procedure for determining the direction of travel shown in Figures 5 and 6.

[0089] Figure 7 is a flowchart showing an example of the route misconversion detection process. The route misconversion detection process shown in Figure 7 is executed when the determination results for the direction of travel of the set route and the direction of travel of the actual route at a common intersection are obtained through the direction of travel determination process shown in Figure 5 or Figure 6. The route misconversion detection process is executed for each common intersection.

[0090] As shown in Figure 7, in S30, the route generation device 10 uses the route misconversion determination unit 14 to determine whether the determination result of the direction of travel of the set route at a common intersection matches the determination result of the direction of travel of the practical route. If the route generation device 10 determines that the determination result of the direction of travel of the set route matches the determination result of the direction of travel of the practical route (S30: YES), it proceeds to S31. If the route generation device 10 determines that the determination result of the direction of travel of the set route does not match the determination result of the direction of travel of the practical route (S30: NO), it proceeds to S32.

[0091] In S31, the route generation device 10 determines that no route conversion errors have occurred at the common intersection. After that, the route conversion error detection process is terminated.

[0092] In S32, the route generation device 10 determines that a route conversion error has occurred at a common intersection. After that, the route conversion error detection process is terminated.

[0093] If the route generation device 10 determines that a route conversion error has occurred at any one of the common intersections, it determines that a route conversion error has occurred in the conversion from the current set route to the actual route. If the route generation device 10 determines that a route conversion error has occurred, it discards the actual route in which the route conversion error occurred. The route generation device 10 may perform the conversion from the set route to the actual route again, or it may notify the driver of the abnormality.

[0094] If the route generation device 10 determines that no route conversion errors have occurred at any common intersection, it determines that no route conversion errors have occurred in the conversion from the currently set route to the practical route. The route generation device 10 transmits information of the practical route in which no route conversion errors have occurred to the vehicle control device 6.

[0095] According to the route generation device 10 of the first embodiment described above, by focusing on intersections (or junctions) where route conversion errors are likely to occur, the presence or absence of route conversion errors can be appropriately determined from the angle of travel at common intersections of the set route and the practical route, and from the road information before and after the common intersection. This makes it possible to appropriately determine whether or not route conversion errors occur when converting from the set route on the navigation map to the practical route on the high-precision map. In addition to intersections, junctions may also be used.

[0096] Specifically, the route generation device 10 determines that a vehicle traveling along the set route will not go straight through the common intersection if the road link located directly in front of the entry link at the common intersection is not the exit link of the set route, since it is highly likely that the road link located closest to 180° in angle with respect to the entry link of the set route is the destination of the vehicle if the set route is not the exit link of the set route. Furthermore, the route generation device 10 determines that a vehicle traveling along the set route will not go straight through the common intersection if it is going straight through the common intersection, since it is assumed that the road type, such as a general road or an expressway, will match between the entry link and the exit link when traveling straight through the common intersection. The same applies to determining the direction of travel at a common intersection in a practical route.

[0097] Thus, the route generation device 10 can appropriately determine the direction of travel at common intersections in the set route and the direction of travel at common intersections in the practical route, and can use these determination results to accurately determine whether or not there are any route conversion errors at common intersections.

[0098] [Second Embodiment] Next, a route generation device according to the second embodiment will be described. Figure 8 is a block diagram showing the route generation device (route misconversion determination device) according to the second embodiment. The route generation device 20 shown in Figure 8 differs from the first embodiment only in the function of the route misconversion determination unit 21.

[0099] Unlike the first embodiment, the route misconversion determination unit 21 in the second embodiment determines whether or not a route misconversion has occurred without determining the direction of travel at a common intersection. For example, the route misconversion determination unit 21 determines that a route misconversion has occurred if the difference (absolute value) between the travel angle of the set route and the travel angle of the practical route at a common intersection is greater than or equal to the allowable angle threshold. The value of the allowable angle threshold is not particularly limited. The allowable angle threshold may be 5°, 10°, 20°, 30°, or 45°.

[0100] The route misconversion determination unit 21 determines that a route misconversion has occurred, for example, when the allowable angle threshold is 30°, and the travel angle of the set route at a common intersection is 180°, while the travel angle of the practical route at the same common intersection is 140°, because the difference is greater than or equal to the allowable angle threshold.

[0101] Furthermore, the allowable angle threshold may be changed according to the number of road links connected to the intersection. The allowable angle threshold may be set to a larger value the fewer the number of road links connected to the intersection. It can be assumed that misjudgments are less likely to occur when there are fewer road links connected to the intersection. In addition, the allowable angle threshold may be changed according to the type of road before and after the common intersection. The route misconversion determination unit 21 may set the allowable angle threshold to a larger value in the case of a common intersection sandwiched between expressways compared to a common intersection sandwiched between general roads. It can be assumed that expressways have a wider road width than general roads, and therefore the angle difference between roads branching off from intersections, etc., is also larger.

[0102] The route misconversion determination unit 21 may determine that no route misconversion has occurred in the conversion from the set route to the practical route if the difference (absolute value) between the travel angle of the set route and the travel angle of the practical route is less than the allowable angle threshold at all common intersections. The route misconversion determination unit 21 may also narrow down the common intersections to be determined. For example, the route misconversion determination unit 21 may only determine common intersections where the travel direction of the set route is a left turn or a right turn.

[0103] The route misconversion determination unit 21 may determine whether or not a route misconversion has occurred based on the road information of the set route and the road information of the actual route. For example, the route misconversion determination unit 21 determines that a route misconversion has occurred if the road type of the set route before and after a common intersection does not match the road type of the actual route before and after the common intersection. The route misconversion determination unit 21 determines that a route misconversion has occurred if the road type of the entry link to the common intersection in the set route is a general road, and the road type of the exit link to the common intersection in the set route is a connecting road to an expressway, while the road type of the entry link to the common intersection in the actual route is a general road, and the road type of the exit link to the common intersection in the actual route is a general road, because the road types before and after the common intersection do not match.

[0104] The route misconversion determination unit 21 may determine that no route misconversion has occurred in the conversion from the set route to the actual route if the road type of the set route matches the road type of the actual route before and after all common intersections.

[0105] In addition, the route misconversion determination unit 21 may determine that a route misconversion has occurred if the road numbers of the set routes before and after a common intersection do not match the road numbers of the actual routes before and after the common intersection. The route misconversion determination unit 21 may also determine that a route misconversion has occurred if the combination of road widths of the set routes before and after a common intersection does not match the combination of road widths of the actual routes before and after the common intersection. The route misconversion determination unit 21 may or may not require a perfect match of road widths. The route misconversion determination unit 21 may determine that the road widths match if the difference (absolute value) between the road width of the set route and the road width of the actual route is less than the allowable width threshold. The allowable width threshold is not particularly limited, but may be 30 cm or 50 cm.

[0106] The route misconversion determination unit 21 may determine route misconversion based on differences in road information, regardless of whether there are common intersections. The route misconversion determination unit 21 may determine that route misconversion has occurred if, for example, the road types of the roads on the set route and the road types of the roads on the actual route do not all match. If the road types of the roads on the set route and the road types of the roads on the actual route do not all match, for example, this would be the case if all the road types on the set route are general roads (e.g., national highways), but the actual route includes roads that are motorways.

[0107] The route misconversion detection unit 21 may determine that a route misconversion has occurred if the road numbers of all roads on the set route do not match the road numbers of all roads on the actual route (if even one road number is mismatched). This assumes that the road numbers are the same for both the navigation map and the high-precision map. The route misconversion detection unit 21 may also determine that a route misconversion has occurred if the road names of all roads on the set route do not match the road names of all roads on the actual route.

[0108] The route misconversion determination unit 21 determines that no route misconversion has occurred if, after performing all of the pre-set route misconversion determinations described above, it is not determined that a route misconversion has occurred. In addition, the route misconversion determination unit 21 may determine that a route misconversion has occurred if the set route or the actual route includes an intersection that is not a common intersection.

[0109] Next, the method for determining incorrect route conversion in the route generation device 20 according to the second embodiment will be described with reference to Figure 9. Figure 9 is a flowchart showing an example of the route incorrect conversion determination process according to the second embodiment.

[0110] As shown in Figure 9, in S40, the route generation device 20 uses the route misconversion determination unit 21 to determine whether the difference between the travel angle of the set route and the travel angle of the practical route is less than the allowable angle threshold at all common intersections. If the route generation device 20 determines that the difference between the travel angle of the set route and the travel angle of the practical route is less than the allowable angle threshold at all common intersections (S40: YES), it proceeds to S41. If the route generation device 20 does not determine that the difference between the travel angle of the set route and the travel angle of the practical route is less than the allowable angle threshold at all common intersections (S40: NO), it proceeds to S43. S40 is NO when the difference between the travel angle of the set route and the travel angle of the practical route is greater than or equal to the allowable angle threshold at at least one common intersection.

[0111] In S41, the route generation device 20 uses the route misconversion determination unit 21 to determine whether the road type of the set route matches the road type of the actual route before and after all common intersections. If the route generation device 20 determines that the road type of the set route matches the road type of the actual route before and after all common intersections (S41: YES), it proceeds to S42. If the route generation device 20 determines that the road type of the set route does not match the road type of the actual route before and after all common intersections (S41: NO), it proceeds to S43.

[0112] In S42, the route generation device 20 determines that no route conversion errors have occurred in the conversion from the currently set route to the actual route. Subsequently, the route conversion error detection process is terminated.

[0113] In S43, the route generation device 20 determines that a route conversion error has occurred in the conversion from the currently set route to the actual route. Subsequently, the process for determining the current route conversion error is terminated.

[0114] In the route generation device 20 according to the second embodiment described above, by focusing on intersections where route conversion errors are likely to occur, the presence or absence of route conversion errors can be appropriately determined from the angle of travel at common intersections of the set route and the practical route, and from the road information before and after the common intersection. This allows for the determination of whether or not route conversion errors occur when converting from the set route on the navigation map to the practical route on the high-precision map. In addition to intersections, branching points may also be used.

[0115] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above. The present invention can be implemented in various forms, starting with the embodiments described above, by making various changes and improvements based on the knowledge of those skilled in the art.

[0116] The route misconversion determination device according to the present invention does not necessarily have to be integrated with the route generation devices 10, 20 (i.e., route misconversion determination units 11, 21). The route misconversion determination device may be a device independent of the device having the route conversion unit 11, and may constitute part of an automated driving system or a driver assistance system. [Explanation of symbols]

[0117] 1...Navigation system, 2...GNSS receiver, 3...HMI, 4...Navigation map database, 5...High-precision map database, 6...Vehicle control device, 10...Route generation device (route misconversion detection device).

Claims

1. A route misconversion detection device that determines whether or not there is a route misconversion when a set route on a navigation map for a vehicle's navigation system is converted to a practical route on a high-precision map, Based on the navigation map and the set route, the location information of the intersection on the set route and the angle of travel at the intersection on the set route are extracted. Based on the high-precision map and the practical route, the location information of the intersection on the practical route and the angle of travel at the intersection on the practical route are extracted. A route misconversion determination device that determines whether or not a route misconversion has occurred based on the travel angle of the set route and the travel angle of the practical route at a common intersection which is a common intersection of the set route and the practical route.

2. Based on the direction of travel of the set path at the common intersection, it is determined whether the vehicle traveling along the set path proceeds straight through the common intersection, and based on the direction of travel of the practical path at the common intersection, it is determined whether the vehicle traveling along the practical path proceeds straight through the common intersection. The route misconversion determination device according to claim 1, which determines that a route misconversion has occurred when the determination result of the direction of travel at the common intersection in the set route does not match the determination result of the direction of travel at the common intersection in the practical route.

3. If, among the multiple road links extending from the aforementioned common intersection, the road link whose angle with respect to the entry link of the set route is closest to 180° is not the exit link of the set route, then it is determined that the vehicle traveling along the set route will not proceed straight through the common intersection. The route misconversion determination device according to claim 2, wherein, among the plurality of road links extending from the common intersection, if the road link whose angle with respect to the entry link of the practical route is closest to 180° is not the exit link of the practical route, the device determines that the vehicle traveling along the practical route will not proceed straight through the common intersection.

4. Based on the navigation map and the set route, the road type of the roads on the set route is extracted, and based on the high-precision map and the actual route, the road type of the roads on the actual route is extracted. A route misconversion determination device according to claim 1 or 2, which determines whether or not the route misconversion has occurred based on the road type of the road on the set route and the road type of the road on the actual route.

5. Based on the road type of the set route before and after the common intersection, it is determined whether the vehicle traveling along the set route proceeds straight through the common intersection, and based on the road type on the practical route before and after the common intersection, it is determined whether the vehicle traveling along the practical route proceeds straight through the common intersection. The route misconversion determination device according to claim 4, which determines that a route misconversion has occurred when the determination result of the direction of travel at the common intersection in the set route does not match the determination result of the direction of travel at the common intersection in the practical route.

6. If the road type of the entry link of the set route and the road type of the exit link of the set route do not match at the aforementioned common intersection, it is determined that the vehicle traveling along the set route will not proceed straight through the common intersection. The route misconversion determination device according to claim 5, which determines that if the road type of the entry link of the practical route at the common intersection does not match the road type of the exit link of the practical route, the vehicle traveling along the practical route will not proceed straight through the common intersection.

7. A method for determining whether a route conversion error has occurred when a set route on a navigation map for a vehicle's navigation system is converted to a practical route on a high-precision map, wherein the method is for determining whether a route conversion error has occurred for a route conversion device, The route misconversion detection device extracts the location information of intersections on the set route and the angle of travel at those intersections on the set route, based on the navigation map and the set route. The route misconversion detection device extracts the location information of intersections on the practical route and the angle of travel at those intersections on the practical route, based on the high-precision map and the practical route. A method for determining whether a route misconversion has occurred, wherein the route misconversion determination device determines whether a route misconversion has occurred based on the angle of travel of the set route and the angle of travel of the practical route at a common intersection which is a common intersection of the set route and the practical route.

Images