JP2013205300A - Driving assist system, method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide information that guides a planned route without giving discomfort to a user even when detouring to a destination point.SOLUTION: The driving assist system is configured to comprise: obtaining an intersection of a straight line for connecting a departure point to the destination point and a detour factor feature for permitting to pass only via at least one passage road section; obtaining the planned route reaching the destination point from the departure point after passing the passage road section; and guiding the detour factor feature as a cause of the detour in a case where a passing distance increases at a predetermined ratio or more than that of a passage of a virtual route passing a virtual road section set at a periphery of the intersection when passing the planned route.

Description

  The present invention relates to a driving support system, method, and program for guiding a planned route.

  Conventionally, a navigation system for guiding a planned route is known, and techniques for performing various types of support are known as functions associated with the route guidance. For example, in Patent Document 1, when the actual travel distance to the facility is significantly longer than the straight distance, the user is notified of this, and information for determining whether or not the facility should be the destination is provided. Techniques to do this are disclosed.

JP 2006-98335 A

  In the conventional technology, the user cannot be notified of the reason why the scheduled route that is guided is long, and therefore, it is not possible to suppress the uncomfortable feeling that the user feels when the planned route is presented. That is, when the planned route is highlighted on the map of the display unit and presented to the user, the user can visually recognize the planned route after the current location on the map. Since the planned route is a route for reaching the destination point from the current location, many planned routes are routes from the current location to the destination location. However, when the planned route is a route that makes a detour due to a detour factor such as a closed road, a river, a track, or the like, the route may go to the destination after passing the route away from the destination around the current location.

If both the current location and the destination location are not displayed on the map, the route away from the destination location is displayed on the map around the current location, and the route to the destination location is not displayed on the map. A situation can also arise. Under such circumstances, if the user knows the approximate position of the destination point, even if it is reported that the distance of the planned route is significantly longer than the straight distance as in Patent Document 1, Many people feel uncomfortable that the planned route is wrong. When the user feels uncomfortable in this way, the user often estimates that the planned route is an incorrect route. When such an estimation is performed, the distance of the planned route is much larger than the straight line distance. Information that is too long does not serve as useful information to correct the estimate. When such estimation is performed, the user may select a route different from the planned route, and as a result, the user does not go to the destination point by a route different from the planned route that was originally reachable at the shortest cost. May fall into a situation where
The present invention has been made in view of the above problems, and it is an object of the present invention to guide a planned route without giving the user a sense of incongruity even when detouring to a destination point.

  In order to achieve the above object, in the present invention, the intersection point between the straight line connecting the starting point and the destination point and the detour factor feature that can be passed only by at least one passing road section is obtained and used for passing. A planned route that reaches the destination point from the departure point through the road section is acquired. Then, when the planned route is passed, the detour factor feature is guided as a cause of the detour when the travel distance increases by a predetermined ratio or more than the virtual route passing through the virtual road section set around the intersection. .

  In other words, it is presumed that if the detour factor feature is detoured and the route is routed, the travel distance will be longer than if the detour factor feature is not detoured. It is assumed that an increase in travel distance occurs due to detouring. In addition, since the detour factor feature can pass only through the passage road section, the virtual route section passes the planned route including the passage road section and the detour factor feature that is passed only through the passage road section. By comparing the travel distance with the virtual route that is supposed to be performed, it is possible to specify whether or not the detour factor feature that is passed by the passing road section causes the detour. Therefore, if the specified detour factor feature is guided as a cause of detouring, the planned route can be guided without giving a sense of incongruity to the user even when detouring to the destination point.

  Here, the intersection acquisition means only needs to be able to acquire an intersection between a straight line connecting the departure point and the destination point and a detour factor feature that can be passed only by at least one passing road section. That is, a straight line connecting the departure point and the destination point can be regarded as being similar to a virtual route for reaching the destination point with the shortest distance from the departure point. Therefore, if it is possible to obtain the intersection where the straight line connecting the departure point and the destination point intersects with the detour factor feature, it is not possible to select the route that reaches the destination point in the shortest distance from the departure point by the detour factor feature ( It can be estimated that a circumstance occurs. Therefore, if the intersection can be obtained, the detouring feature from which the intersection was obtained is a detouring feature that may be detoured on the planned route from the departure point to the destination point. Then, it is determined whether or not the detour factor feature causes a detour. In addition, the intersection is used as a reference when setting a virtual route based on the detour factor feature.

  The detour factor feature is a feature that can be passed only by at least one passing road section. In other words, since it cannot move from one side of the bypass factor feature to the other side unless it passes through the passing road section, the feature that can be bypassed to pass through the passing road section. Can be used as a detour factor feature. Of course, it is sufficient that the passing road section is set to one or more places. For example, a bridge for crossing a river is a passage road section, and a user who uses a driving support system can usually cross a river only by the passage road section. Therefore, the bridge is a passage road. It becomes a section. And the said bridge may be installed in several places.

  Note that the detour factor feature can pass only through the passing road section, but it is assumed that the passage assumed here is made by a movement equivalent to a normal movement by the user. In other words, even if it is possible to pass the detour feature by special movement, if you must use the road section for passing to pass the detour feature unless you move specially, Only the road section can pass the detour factor feature. For example, movements where pedestrians swim across a river or movements where a vehicle enters the river and crosses the river are excluded. Is a detour factor feature.

  The planned route acquisition means only needs to be able to acquire a planned route that reaches the destination point from the departure point through the passing road section. That is, it is only necessary to be able to specify a route that reaches from the departure point to the destination point and that is a route that is intended to guide the cause of the detour through the route that passes through the passing road section. Therefore, for example, a route for reaching a destination point from a departure point is searched, and the route includes a road segment for passing a detour factor feature in which an intersection with a straight line connecting the departure point and the destination point is acquired. In such a case, it is possible to adopt a configuration in which the route is acquired as a planned route. The departure point may be selected by the user or may be the user's current location (including the current location of the vehicle on which the user is boarding). Of course, the search may be performed by an external device. In this case, the planned route is provided to the driving support system by communication or the like.

  The guide means use the detour feature as a cause of detour when the travel distance increases by more than a predetermined ratio when passing the planned route through the virtual route passing through the virtual road section set around the intersection It only has to be able to guide. That is, when it is determined that the planned route can be considered to be a route that reaches the destination point by detouring by comparing the planned route with the virtual route, the passing road section on the planned route and the virtual route It is only necessary that the detour factor feature passed by the virtual road section can be identified and guided as a cause of detour. Of course, guidance can be implemented in various ways, and can be implemented using audio output, image output, or the like.

  Here, the virtual road section is a road section that is virtually set at a position where the detour factor feature cannot actually pass, and may be set around the intersection. That is, it is only necessary to set the virtual road section so that it can be assumed that the intersection or the vicinity of the intersection can be virtually passed. When a virtual road section is set around the intersection, it is preferable to set a virtual road section whose end point is another point (for example, a node included in the map information) existing around the intersection. For example, a virtual road section may be set by virtually setting a road section whose end point is a node closest to the intersection or a node existing within a predetermined distance around the intersection.

  The traffic distance may be a configuration that compares the traffic distance for all sections of the planned route and the virtual route as long as it can be compared with the case of passing the planned route and the case of passing the virtual route, In the planned route and the virtual route, a configuration may be used in which the travel distance to be traveled to reach the predetermined reference point from the departure point is compared.

  In the former (comparison of the travel distance for all sections of the planned route and the virtual route), the travel distance traveled to reach the destination from the departure point on the planned route, and from the departure point to the destination point on the virtual route When the ratio of the distance traveled to reach the vehicle is greater than or equal to a predetermined ratio, the detour factor feature is guided as a cause of detour. According to this configuration, it is possible to determine whether or not the cause of the detour should be guided using the easily specified travel distance. In this case, the virtual route is a route that reaches the destination point through the virtual road section after leaving the departure point. Thus, for example, a route from the departure point to the first point set on the departure point side with respect to the intersection, and a straight virtual road from the first point to the second point set on the destination point side with respect to the intersection. It is possible to adopt a configuration in which the sum of the route passing through the section and the route reaching the destination point from the second point is a virtual route.

  On the other hand, in the latter (configuration in which the travel distance to be traveled to reach the predetermined reference point from the departure point on the planned route and the virtual route is compared), the virtual route is used to pass through the bypass road section for the detour factor feature. The reference point needs to be set so that the distance that has been increased over the route is included in the comparison travel distance, and the detour factor that exceeds the detour factor feature in both the planned route and the virtual route, detour A point set on the factor feature, a point immediately before reaching the detour factor feature, or the like can be set as the predetermined reference point. The predetermined ratio is a rate of increase in the travel distance that can be regarded as a detour, and can be defined by specifying the rate of increase in the travel distance that makes the user feel uncomfortable by using statistics or the like. is there.

  For example, the travel distance traveled to reach the periphery of the passing road section from the departure point on the planned route, and the passage to reach the first point set on the departure point side from the intersection on the virtual route It is possible to adopt a configuration in which the detour factor feature is guided as a detour cause when the ratio of the travel distance to be performed is equal to or greater than a predetermined ratio. According to this configuration, since the travel distance is compared by excluding the factor after passing the detour factor feature, the increase rate of the travel distance can be directly evaluated. In this configuration, a route from the departure point to the first point may be a virtual route.

  Furthermore, when there are a plurality of detour factor features that intersect a straight line connecting the departure point and the destination point, it may be configured to determine whether or not each detour factor feature causes a detour. That is, when a straight line connecting the departure point and the destination point intersects with a plurality of detour factor features, an intersection is obtained for each of the plurality of detour factor features. Furthermore, a virtual route that passes through a virtual road section set for one bypass factor feature selected from a plurality of bypass factor features and passes through the passage road section for other bypass factor features is a virtual route. And Then, when the planned route is passed, among the detour factor features whose travel distance increases by a predetermined ratio or more than the virtual route, the detour factor feature having the largest increase in the travel distance is guided as a cause of the detour. The configuration.

  According to this configuration, it is possible to determine whether each detour factor feature causes a detour based on the virtual route and the planned route for each of the plurality of detour factor features. Then, among the detour factor features that cause the detour, the detour factor feature having the largest increase in the travel distance is guided as the cause of the detour, so that the cause of the greatest detour is clearly shown to the user. can do. Of course, the configuration for guiding the cause of the detour is limited to the configuration that guides the detour factor feature having the largest increase in the travel distance among the detour factor features that cause the detour as the cause of the detour. Not. For example, a configuration in which a detour factor having an increase rate of a travel distance of a predetermined ratio or more is guided as a cause of detour, or the top M detour factor sites having a large increase in the travel distance (M is an integer of 2 or more) It is possible to adopt a configuration that guides an object as a cause of detour.

  Furthermore, when there are a plurality of detour factor features that intersect the straight line connecting the departure point and the destination point, it may be configured to determine whether or not the detour factor features are combined to cause a detour. . That is, when a straight line connecting the departure point and the destination point intersects with a plurality of detour factor features, an intersection is obtained for each of the plurality of detour factor features. Furthermore, a virtual road section set for two or more bypass factor features selected from a plurality of bypass factor features is passed, and a route passing through the passing road section is virtually assumed for other bypass factor features. A route. Then, when the planned route is passed, among the detour factor features that increase the travel distance by a predetermined ratio or more than the virtual route, the detour factor features having the largest increase in the travel distance are bypassed. The structure is to guide as a cause.

  According to this configuration, for a combination of a plurality of bypass factor features, it can be determined whether each combination causes a bypass. Then, among the combinations causing the detour, the detour causing the largest detour cause is guided to the user as the cause of the detour because the combination of the detour factor features having the largest increase in the travel distance is guided. The combination of factor features can be presented clearly. Of course, as a configuration to guide the combination of detour factor features as the cause of detour, among the detour factor feature combinations that cause the detour, of the detour factor feature that has the largest increase in travel distance It is not limited to the structure which guides a combination as a cause of a detour. For example, a configuration that guides a combination of detour factor features whose travel distance increase rate is greater than or equal to a predetermined ratio, or detours of the top M groups (M is an integer of 2 or more) with a large increase in travel distance It is possible to adopt a configuration that guides the combination of factor features as a cause of detour.

  Further, as in the present invention, when passing a planned route, a method for determining whether to guide a detour factor feature as a cause of detouring when the travel distance increases by a predetermined ratio or more than when passing a virtual route Can also be applied as a program or method. In addition, the system, program, and method as described above may be realized as a single device, or may be realized using components shared with each part of the vehicle, and include various aspects. It is a waste. For example, it is possible to provide a navigation system, method, and program that include the system described above. Further, some changes may be made as appropriate, such as a part of software and a part of hardware. Furthermore, the invention can be realized as a recording medium for a program for controlling the system. Of course, the software recording medium may be a magnetic recording medium, a magneto-optical recording medium, or any recording medium to be developed in the future.

It is a block diagram of the navigation apparatus containing a driving assistance system. It is a flowchart which shows a driving assistance process. It is a flowchart which shows a detour cause determination process. It is a figure which illustrates the road around the present location and destination point of a vehicle.

Here, embodiments of the present invention will be described in the following order.
(1) Configuration of navigation device:
(2) Driving support processing:
(2-1) Detour cause determination processing:
(3) Other embodiments:

(1) Configuration of navigation device:
FIG. 1 is a block diagram showing a configuration of a navigation device 10 including a driving support system according to the present invention. The navigation apparatus 10 includes a control unit 20 including a CPU, a RAM, a ROM, and the like, and a recording medium 30, and the control unit 20 can execute a program stored in the recording medium 30 and the ROM. In the present embodiment, the driving support program 21 can be executed as this program. The driving support program 21 has a function of guiding a route and a function of guiding a detour factor feature that causes a detour when guiding a planned route to detour to the destination. It is executed together with a navigation program (not shown).

  Map information 30a is recorded in the recording medium 30 in advance. The map information 30a is information used for searching a route and specifying the position of the vehicle, and for specifying node data indicating the position of the node set on the road on which the vehicle travels and the shape of the road between the nodes. Shape interpolation point data indicating the position of the shape interpolation point, link data indicating the connection between nodes, data indicating the position of the road and its surrounding features, and the like. These features can be destination points. The link data is associated with the link cost of the road section indicated by each link. In the map information 30a, the position of a node or the like is represented by a two-dimensional orthogonal coordinate system that specifies the position using latitude and longitude as coordinate values.

  Further, the data relating to the feature included in the map information 30a includes data indicating that it is a detour factor feature. In this embodiment, the detour factor feature is a feature that obstructs the passage of the vehicle over a wide range such as a river or a track, and it is necessary to use a passing road section in order to pass the feature. Such a feature. That is, since it cannot move from one side of the detour factor feature to the other side unless it passes through the passing road section, there is a feature that can cause a detour to pass through the passing road section. It is assumed to be a detour factor feature in advance. Of course, it is sufficient that the passing road section is set to one or more places. For example, a bridge for crossing a river is a passage road section, and a user who uses a driving support system can usually cross a river only by the passage road section. Therefore, the bridge is a passage road. It becomes a section. In addition, the level crossing for crossing the track is a passing road section, and the user who uses the driving support system can usually cross the track only by the passing road section. It becomes a section. And the said bridge and the said level crossing may be installed in several places.

  Note that the detour factor feature can pass only through the passing road section, but it is assumed that the passage assumed here is made by a movement equivalent to a normal movement by the user. In other words, even if it is possible to pass the detour factor feature by a special movement, if the special road is not used and the detour factor feature cannot be passed unless it is used, Only by the detour factor feature can be passed. For example, a movement of a vehicle entering a river and crossing the river is excluded, and the river is a detour factor feature if it can pass only by a bridge equivalent to a normal passage or road.

  The data indicating the detour factor feature included in the map information 30a is associated with information indicating that the feature is the detour factor feature, and includes information for specifying the position of the detour factor feature. include. As information for specifying the position of the detour factor feature, for example, coordinate information for specifying the center position (the center position in the width direction) in the direction perpendicular to the direction in which the detour factor feature extends, and the center position It can be configured by width information indicating a length (width) in a direction perpendicular to a direction in which the detour factor feature extends.

  The vehicle on which the navigation device 10 according to this embodiment is mounted includes a GPS receiver 41, a vehicle speed sensor 42, a gyro sensor 43, and a user I / F unit 44. The GPS receiver 41 receives radio waves from GPS satellites and outputs information for calculating the current location of the vehicle via an interface (not shown). The control unit 20 acquires this signal and acquires the current point of the vehicle. The vehicle speed sensor 42 outputs a signal corresponding to the rotational speed of the wheels provided in the vehicle. The control unit 20 acquires this signal via an interface (not shown) and acquires the speed of the vehicle. The gyro sensor 43 outputs a signal corresponding to the angular velocity acting on the vehicle. The control unit 20 acquires this signal via an interface (not shown) and acquires the traveling direction of the vehicle. The vehicle speed sensor 42, the gyro sensor 43, and the like are used for correcting the current position of the vehicle specified from the output signal of the GPS receiver 41. Further, the current location of the vehicle is corrected as appropriate based on the travel locus of the vehicle.

  The user I / F unit 44 is an interface unit for inputting a driver's instruction and providing various information to the driver, and includes a display unit such as a touch panel display (not shown), a switch, a speaker, and the like. Yes. In the present embodiment, it is possible to display a map on the display unit included in the user I / F unit 44 and highlight a road corresponding to the planned route displayed on the map.

  In this embodiment, it is the structure which guides the detour factor feature which causes a detour in the planned route detouring to the destination point. In order to realize the guidance, the driving support program 21 includes an intersection acquisition unit 21a, a planned route acquisition unit 21b, and a guide unit 21c.

  The driving support program 21 is executed in a state where the navigation program is being executed in the navigation device 10, and when the navigation program is executed, the control unit 20 includes the GPS receiving unit 41, the vehicle speed sensor 42, and the gyro sensor 43. The current location of the vehicle is acquired based on the output signal and the map information 30a, the map information 30a is referenced to generate image data for drawing a map around the current location at a predetermined scale, and the user I / F unit 44 for output. As a result, the user I / F unit 44 displays a map around the current location of the vehicle on the display unit.

  The intersection acquisition unit 21a is a module that causes the control unit 20 to execute a function of acquiring an intersection point between a straight line connecting a departure point and a destination point and a detour factor feature that can be passed only by at least one passing road section. is there. That is, in the present embodiment, the straight line connecting the departure point and the destination point is regarded as being similar to a virtual route for reaching the destination point with the shortest distance from the departure point. And if the intersection where the straight line connecting the departure point and the destination point intersects the detour factor feature can be acquired, the route that reaches the destination point from the departure point by the detour factor feature cannot be selected ( It can be considered that there is a possibility that a circumvention occurs. Therefore, the control unit 20 acquires an intersection of a straight line connecting the departure point and the destination point and a detour factor feature that can be passed only by at least one passing road section. And when an intersection can be acquired, it becomes a target which determines whether the said detour factor feature is the cause of detour. The intersection is used as a reference when setting a virtual route based on the detour factor feature.

  Specifically, the control unit 20 acquires the position of the departure point and the destination point of the planned route set by the process of the planned route acquisition unit 21b described later, and refers to the map information 30a by the process of the intersection acquisition unit 21a. Then, a straight line connecting the position of the departure point and the destination point is specified. Further, the control unit 20 identifies the center position of the detour factor feature existing between the position of the departure point and the destination point by referring to the data indicating the detour factor feature of the map information 30a by the process of the intersection acquisition unit 21a. To do. Here, the control part 20 specifies the center position which continues over the direction where a detour factor feature extends. That is, a line connecting the central positions is specified. And the control part 20 acquires the intersection of the center position lined in the said linear form, and the straight line which connects the position of a departure point and the destination point. Note that if there are a plurality of detour factor features between the departure point and the destination point, an intersection is acquired for each detour factor feature.

  The planned route acquisition unit 21b is a module that causes the control unit 20 to execute a function of acquiring a planned route that reaches the destination point from the departure point through the passing road section. That is, the control unit 20 specifies a route that reaches from the departure point to the destination point and that passes through the passing road section as a target route that guides the cause of the detour when detouring is performed. Specifically, the control unit 20 uses the current point of the vehicle as the departure point, acquires the destination point input by the input unit of the user I / F unit 44, and selects a route for reaching the destination point from the departure point. Explore. The route can be searched using a known algorithm such as the Dijkstra method. Then, when the searched route includes a road section for passing a detour factor feature in which an intersection of a straight line connecting the departure point and the destination point is acquired, the route is acquired as a planned route. Here, the departure point may be selected by the user.

  The guide unit 21c causes the detour factor feature to detour when the travel distance increases by a predetermined ratio or more when the planned route passes along the virtual route passing through the virtual road section set around the intersection. This is a module that causes the control unit 20 to execute the function of guiding as follows. That is, the control unit 20 determines whether or not the planned route can be regarded as a route that bypasses and reaches the destination point by comparing the planned route and the virtual route. Here, the travel distance is a distance for comparison between the case of passing the planned route and the case of passing the virtual route. In the present embodiment, the travel distance is compared for all sections of the planned route and the virtual route. To do. Specifically, the control unit 20 refers to the map information 30a and identifies road sections constituting the planned route. Then, the control unit 20 specifies the distance of each road section based on the position of the node indicating the end point of each road section that constitutes the planned path, and calculates the total distance of each road section. Get the distance traveled to reach the destination from the departure point.

  On the other hand, the control unit 20 assumes that the detour factor feature can pass through the virtual road section, reaches the virtual road section from the departure point, and further travels from the virtual road section to the destination point. To obtain a virtual route. Specifically, the control unit 20 refers to the map information 30a, and sets the first node closest to the intersection on the departure point side from the intersection of the straight line connecting the departure point and the destination point and the detour factor feature. Get as a point. In addition, the control unit 20 refers to the map information 30a, and acquires a node closest to the intersection as the second point on the destination point side of the intersection. And the control part 20 sets a virtual road area by assuming that it can pass through the virtual road area which makes the said 1st point and the 2nd point the end point.

  Further, the control unit 20 refers to the map information 30a and searches for a first route that reaches the first point from the departure point and a second route that reaches the destination point from the second point. Furthermore, the control unit 20 is configured by the sum of each route, that is, a route that passes through the first route, a straight virtual road section that reaches the second point from the first point, and a route that passes through the second route. Get the route as a virtual route. Then, the control unit 20 specifies the distance of each road section based on the position of the node indicating the end point of each road section that constitutes the virtual path, and calculates the total distance of each road section. Get the distance traveled to reach the destination from the departure point.

  When the travel distance of the planned route and the travel distance of the virtual route are acquired, the control unit 20 determines whether the ratio of the travel distance of the planned route and the travel distance of the virtual route is greater than or equal to a predetermined ratio (threshold). Determine. When it is determined that the ratio is equal to or greater than the predetermined ratio, the control unit 20 causes the detour factor feature passed by the passing road section on the planned route and the virtual road section on the virtual route to cause the detour. As specified. That is, it is estimated that if the detour factor feature is detoured and the route is passed, the travel distance becomes longer than the case where the detour factor feature is not detoured. Therefore, in this embodiment, the increase degree of the travel distance is a predetermined ratio or more. In some cases, it is considered that an increase in the travel distance by detouring the detour factor feature occurs.

  In addition, since the detour factor feature can pass only through the passage road section, the virtual route section passes the planned route including the passage road section and the detour factor feature that is passed only through the passage road section. By comparing the travel distance with the virtual route that is supposed to be performed, it is possible to specify whether or not the detour factor feature that is passed by the passing road section causes the detour. Moreover, according to the above structure, it can be determined whether the cause of a detour should be guided using the easily identifiable traffic distance. The predetermined ratio (threshold) is an increase rate of the travel distance that can be regarded as a detour, and is defined by specifying the increase rate of the travel distance that makes the user feel uncomfortable by using statistics or the like. Is possible.

  When the cause of detouring is specified as described above, the control unit 20 informs the user I / F unit 44 that the detour factor feature detours together with the image data indicating the planned route. Audio data is output. As a result, the planned route is displayed on the display unit of the user I / F unit 44, and sound for guiding that the detour factor feature is detouring is output from the speaker of the user I / F unit 44. The As a result, the planned route can be guided without giving the user a sense of incongruity even when detouring to the destination point.

(2) Driving support processing:
Next, driving support processing by the driving support program 21 will be described. In this embodiment, when the route search start instruction by the user is received by the processing of the navigation program, the control unit 20 executes the driving support program 21. FIG. 2 is a flowchart showing a driving support process executed by the driving support program 21. When the process of the driving support program 21 is started, the control unit 20 acquires a route between the departure point and the destination point by the process of the planned route acquisition unit 21b (step S100). That is, the control unit 20 uses the current point of the vehicle as the departure point, acquires the destination point input by the input unit of the user I / F unit 44, and reaches the destination point from the departure point with reference to the map information 30a. Search for a route for.

  FIG. 4 is a diagram showing a surrounding road between the departure point S and the destination point G, and an example in which a river Ri and a track Ra exist as detour factor features between the departure point S and the destination point G. Is shown. In the example shown in FIG. 4, an example of a route searched by a thick straight line between the departure point S and the destination point G is shown. In FIG. 4, a bridge Br and a level crossing Cr, which are passage road sections that can pass through the river Ri and the line Ra, are indicated by solid lines, and a bridge Bi and a level crossing Ci as virtual road sections are indicated by hatching.

  Next, the control part 20 acquires the straight line which connects a departure point and a destination point with reference to the map information 30a by the process of the intersection acquisition part 21a (step S105). In the example shown in FIG. 4, a straight line connecting the starting point S and the destination point G is indicated by a thin broken line. Next, by the process of the intersection acquisition unit 21a, the control unit 20 refers to the map information 30a and performs the acquisition process of the intersection of the straight line connecting the departure point and the destination point and the detour factor feature (step S110). That is, when the control unit 20 searches and searches for an intersection between the straight line acquired in step S105 and a line connecting the center positions of the feature registered in the map information 30a as the detour factor feature, the intersection is detected. Get as. In the example shown in FIG. 4, the intersection Pi is shown on the river Ri as the detour factor, and the intersection Pa is shown on the line Ra as the detour factor.

  Next, the control unit 20 determines whether or not an intersection is acquired by the process of the intersection acquisition unit 21a (step S115). When the intersection is not acquired, it is considered that there is no detour in the planned route, and the control unit 20 guides the planned route (step S140). That is, the control unit 20 refers to the map information 30a, identifies road sections on the planned route displayed on the map, generates image data for emphasizing each road section, and generates the user I / F unit 44. Output for. As a result, on the display unit of the user I / F unit 44, guidance for emphasizing the planned route on the map is performed.

On the other hand, when the intersection is acquired in step S115, the control unit 20 acquires the planned route by the processing of the planned route acquisition unit 21b (step S120). That is, the control unit 20 acquires the route searched in step S100 as the planned route. In the example shown in FIG. 4, routes L ₇ , L ₈ , L ₉ , L ₄ , L ₅ , and L ₆ indicated by solid lines are scheduled routes. Next, the control part 20 performs a detour cause determination process by the process of the guide part 21c (step S125). In the present embodiment, the detour cause determination process is a process of identifying the feature that caused the detour among the detour factor features and identifying the largest detour cause as the guidance target.

  When the detour cause determination process is performed, the control unit 20 determines whether there is a detour factor feature to be guided by the process of the guide unit 21c (step S130). If it is not determined that it exists, the planned route is guided in step S140. On the other hand, when it is determined in step S130 that there is a detour factor feature to be guided, the control unit 20 guides the planned route along with the cause of detouring by the processing of the guide unit 21c (step S135). That is, the control unit 20 generates image data indicating the planned route for the user I / F unit 44, generates voice data for guiding that the detour factor feature is detoured, and Output to the I / F unit 44. As a result, the planned route is displayed on the display unit of the user I / F unit 44, and sound for guiding that the detour factor feature is detouring is output from the speaker of the user I / F unit 44. The

(2-1) Detour cause determination processing:
Next, the detour cause determination process in step S125 will be described in detail. FIG. 3 is a flowchart showing a detour cause determination process. In the detour cause determination process, the control unit 20 specifies a candidate feature (or candidate feature group) to be processed (step S200). In the present embodiment, a loop process that repeats the processes of steps S200 to S235 as necessary is adopted, and candidate features (or candidate feature groups) that differ for each loop process are set as processing targets, and candidates for processing targets are set. Specify whether a feature (or candidate feature group) is causing a detour.

  The processing target is a candidate feature group composed of one candidate feature or a plurality of candidate features, and a straight line connecting the departure point S and the destination point G and a plurality of detour factors by the process of step S110. When it is clear that features intersect, one detour factor feature is selected from a plurality of detour factor features and becomes a candidate feature. Further, two or more detour factor features are selected from a plurality of detour factor features to form a candidate feature group. In other words, each of the detour factor features alone does not cause a detour, but when a plurality of detour factor features are combined to cause a detour, the combination is the cause of the detour The candidate feature group is also processed.

  In the present embodiment, the loop processing is repeated until the processing of steps S200 to S235 is executed with all of the selectable candidate features or candidate feature groups as processing targets. For this reason, in step S200, a candidate feature or candidate feature that is not selected as a processing target in the processing in steps S200 to S235 from among selectable candidate features or candidate feature groups, or It will be identified as a candidate feature group. For example, in the example shown in FIG. 4, each of the river Ri and the line Ra becomes a selectable candidate feature, and a combination of the river Ri and the line Ra becomes a selectable candidate feature group. The processing of steps S200 to S235 is executed with the processing targets of Ra, the combination of the river Ri and the line Ra.

Next, the control unit 20 acquires a first point on the departure point side from the intersection and a second point on the destination point side from the intersection (step S205). That is, the control unit 20 refers to the map information 30a and specifies the distance between the departure point and the intersection from the node data indicating the departure point and the intersection. And the node which shows the point nearest to the intersection among the nodes which show the point whose distance from the departure point is shorter than the said distance is specified, and the point which the said node shows is made into the 1st point. In FIG. 4, when the river Ri is a candidate feature, the point acquired as the first point on the departure point side from the intersection Pi is the first point N _vi1 , and the track Ra is a candidate feature. A point acquired as the first point on the departure point side from the intersection Pa is indicated as a first point _Nva1 . When the combination of the river Ri and the track Ra is a candidate feature group, both the point N _vi1 and the point N _va1 are the first points.

Further, the control unit 20 refers to the map information 30a and specifies the distance between the destination point and the intersection point from the node data indicating the destination point and the intersection point. And the node which shows the point nearest to the intersection among the nodes which show the point where the distance from the destination point is shorter than the said distance is specified, and the point which the said node shows is made into the 2nd point. In FIG. 4, when the river Ri is a candidate feature, the point acquired as the second point on the destination point side from the intersection Pi is the second point N _vi2 , and the track Ra is the candidate feature A point acquired as a second point on the destination point side from the intersection Pa is indicated as a second point _Nva2 . When the combination of the river Ri and the track Ra is a candidate feature group, both the point N _vi2 and the point N _va2 are the second points. The first point and the second point related to the same intersection are the end points of the virtual road section. For example, in the example shown in FIG. 4, the first point N _vi1 and the second point N _vi2 are end points of the bridge Bi that is a virtual road section.

  Next, the control unit 20 searches for a virtual route (step S210). In the present embodiment, a virtual road section set for a candidate feature (or candidate feature group) is passed, and a bypass road section is used for a detour factor feature other than the candidate feature (or candidate feature group). The route that passes is a virtual route. Specifically, when any candidate feature is a processing target, the control unit 20 refers to the map information 30a, and is a first point set based on the intersection on the candidate feature from the departure point. The route from the second point set based on the intersection point on the candidate feature to the destination point is searched. At the first point and the second point, since it is assumed that a straight virtual road section connecting these points can be passed, the virtual route is specified by the above processing.

In the example shown in FIG. 4, when the river Ri is a candidate feature, the route that passes through the bridge Bi that is the virtual road section and the railroad crossing Cr that is the passage road section is a virtual route. A route L ₁ from a starting point S to a first point N _{vi1 indicated} by a one-dot chain line, a route L ₂ on a virtual road section indicated by a one-dot chain line, and a route L from a second point N _vi2 to a point Nc _indicated by a one-dot chain line ₃ , a route L ₄ from a point Nc to a point N _ra1 indicated by a solid line, a route L ₅ on a passing road section indicated by a solid line, and a route L ₆ from a point N _ra2 to a destination point G indicated by a solid line Configure a virtual route.

In the example shown in FIG. 4, when the track Ra is a candidate feature, the route that passes through the railroad crossing Ci that is a virtual road section and the bridge Br that is a passage road section is a virtual route, so A route L ₇ from the starting point S to the point N _ri1 shown, a route L ₈ on the passing road section indicated by the solid line, a route L ₉ from the point N _ri2 to the point Nc indicated by the solid line, and a point indicated by the alternate long and _short dash line a path L ₁₀ of Nc~ to the first point N _va1, and virtual path L ₁₁ on the road segment, the route L ₁₂ and the virtual path to the second point N _va2 ~ destination point G shown by a chain line shown by a dashed line Configure.

  When the candidate feature group is a processing target and the candidate feature group is composed of N (N is an integer of 2 or more) detour factor features, the control unit 20 refers to the map information 30a, The virtual route is specified by repeating the route search process a total of N + 1 times. At this time, in the n-th route search process (where n is an integer from 1 to (N + 1)), the second point closest to the departure point is n−1 and the first point closest to the departure point is the end point. It is configured to search for the route. . However, the starting point in the first repetition is not the second point but the starting point. Further, the end point in the N + 1th repetition is not the first point but the destination point. Since it is assumed that a straight virtual road section connecting these points can be passed between the first point and the second point, the route search process is repeated by a total of N + 1 times. The route is specified.

For example, in the example shown in FIG. 4, when the combination of the river Ri and the line Ra is a candidate feature group, the candidate feature group is composed of two detour factor features. By repeating this process, a route passing through the bridge Bi and the level crossing Ci, which are virtual road sections, is specified as a virtual route. That is, in the first route search process, a route is searched from the starting point as the starting point and the first point N _vi1 closest to the starting point as the ending point. For example, the starting point S to D shown by the one-dot chain line in FIG. A route L ₁ to the first point N _vi1 is obtained. In the second route search process, a route is searched starting from the second point N _vi2 closest to the starting point and starting from the first point N _va1 closest to the starting point. For example, FIG. A route L ₃ from the second point N _vi2 to the point Nc _{indicated by the} one-dot chain line and a route L ₁₀ from the point Nc to the first point N _va1 indicated by the one-dot chain line are obtained. In the third route search process, a route is searched starting from the second point N _va2 that is second closest to the starting point and ending at the destination point. For example, the second point N _va2 ~ path L ₁₂ to the destination G is obtained. Then, constituting the virtual path by adding a path L ₂ on the virtual road section indicated by the obtained path dashed line, and a path L ₁₁ on the virtual road section indicated by a chain line.

  Next, the control unit 20 acquires a travel distance (referred to as a virtual passing distance) when the entire route of the virtual route is traveled (step S215). That is, the control unit 20 refers to the map information 30a, specifies the distance for each road section based on the distance between the positions of the nodes indicating the end points of the road section constituting the virtual route, and virtually passes the sum of the distances of the road sections. Get as distance.

  Next, the control unit 20 acquires a travel distance (referred to as a planned passing distance) when the entire route of the planned route is traveled (step S220). That is, the control unit 20 refers to the map information 30a, specifies the distance for each road section based on the distance between the positions of the nodes indicating the end points of the road section constituting the planned route, and passes the sum of the distances of each road section. Get as distance.

Next, the control unit 20 determines whether or not the planned passing distance / virtual passing distance is greater than or equal to the threshold (step S225). That is, when the scheduled route is passed, it is determined whether or not the travel distance increases by a predetermined ratio or more than when the candidate route (or candidate feature group) to be processed is passed along the virtual route. For example, in the example shown in FIG. 4, when the river Ri is a candidate feature, (distance of the routes L ₇ , L ₈ , L ₉ , L ₄ , L ₅ , L ₆ ) / (routes L ₁ , L ₂ , It is determined whether or not the distances L ₃ , L ₄ , L ₅ , and L ₆ are equal to or greater than a threshold value, and if the line Ra is a candidate feature (routes L ₇ , L ₈ , L ₉ , L ₄ , It is determined whether or not (distance of L ₅ , L ₆ ) / (distance of routes L ₇ , L ₈ , L ₉ , L ₁₀ , L ₁₁ , L ₁₂ ) is equal to or greater than a threshold value. In the example shown in FIG. 4, when the combination of the river Ri and the line Ra is a candidate feature group, (distance of the routes L ₇ , L ₈ , L ₉ , L ₄ , L ₅ , L ₆ ) / (route L It is determined whether or not (distances ₁ , L ₂ , L ₃ , L ₁₀ , L ₁₁ , L ₁₂ ) are equal to or greater than a threshold value.

  When it is determined in step S225 that the planned passing distance / virtual passing distance is greater than or equal to the threshold, the candidate feature (or candidate feature group) is identified as a cause of detouring (step S230). On the other hand, if it is not determined in step S225 that the planned passing distance / virtual passing distance is greater than or equal to the threshold value, step S230 is skipped. Therefore, each of the candidate feature and the candidate feature group determined that the planned passing distance / virtual passing distance is greater than or equal to the threshold value in the course of the loop processing of steps S200 to S230 is specified as a cause of detouring.

  Next, the control unit 20 determines whether or not the process of determining whether or not it is a cause of detouring all candidate features and candidate feature groups as processing targets (step S235). If it is not determined that the process of determining whether or not the candidate feature and the candidate feature group are to be detoured as processing targets is completed, the processes in and after step S200 are repeated.

  On the other hand, if it is determined in step S235 that the process of determining whether or not all candidate features and candidate feature groups are to be detoured as processing targets has ended, the control unit 20 determines that the cause of detouring is the cause. It is determined whether or not there is a detour factor feature (step S240). That is, it is determined whether or not at least one candidate feature (or candidate feature group) is a detour factor feature. If it is not determined in step S240 that there is a detour factor feature that causes a detour, step S245 is skipped. In this case, it is considered that there is no detour factor feature to be guided.

  On the other hand, when it is determined in step S240 that there is a detour factor feature that causes a detour, the control unit 20 specifies a detour factor feature to be guided (step S245). In the present embodiment, the candidate feature (or candidate feature group) having the longest planned distance / virtual passage distance is set as the detour factor feature to be guided. In other words, among the detour factor features that increase the travel distance by a predetermined ratio or more when passing the planned route, the detour factor feature (or the detour factor feature having the largest increase in the travel distance) is increased. Combination) is a detour factor feature to be guided. In step S245, when the detour factor feature to be guided is specified, after the determination in step S130 in FIG. 2, the guidance target detour factor feature is guided along with the planned route in step S135 as a cause of detouring. become.

  According to the above configuration, it is possible to determine whether each detour factor feature causes a detour based on the virtual route and the planned route for each of the plurality of detour factor features. Further, for a combination of a plurality of detour factor features, it can be determined whether each combination causes a detour. And, among the detour factor features causing the detour, the detour factor feature or the combination of detour factor features having the largest increase in the travel distance is guided to the user as the cause of the detour, which is the largest for the user. The cause of the detour can be clearly presented.

(3) Other embodiments:
The above embodiment is an example for carrying out the present invention, and when the planned route is passed, the detour factor feature is guided as a cause of the detour when the travel distance increases by a predetermined ratio or more than the virtual route. As long as it is determined whether to do so, various other embodiments can be adopted. For example, the search for the planned route may be performed by an external device different from the navigation device 10, and in this case, the planned route is provided to the navigation device 10 by communication or the like.

  Furthermore, the navigation device 10 according to the above-described embodiment is a navigation device used in a vehicle, and may be provided in the vehicle or may be realized by a mobile terminal. Of course, the vehicle in which the navigation device 10 is used is not limited to a passenger car, and may be any vehicle such as a two-wheeled vehicle, or the navigation device 10 may be used by a user who is not on the vehicle, for example, a pedestrian, Various modes can be adopted.

  Furthermore, the virtual road section is a road section that is virtually set at a position where it cannot actually pass the detour factor feature, and may be set around the intersection. Therefore, the virtual road section may be set so that it can be considered that the intersection can be virtually passed. In this case, for example, a virtual node is set at a position where a straight line extending from the intersection to both sides of the detour factor feature in the width direction intersects the road section, and a road section with each node as an end point is set virtually. And a virtual road section.

  Furthermore, in order to determine whether or not the travel distance increases by a predetermined ratio or more when passing the planned route, compared to passing the virtual route passing through the virtual road section set around the intersection, the planned route and virtual It is good also as a structure which compares the traffic distance in a part of path | route. In other words, a configuration may be used in which the travel distance to be traveled in order to reach a predetermined reference point from the departure point in the planned route and the virtual route may be compared. Specifically, it is necessary to set the reference point so that the distance compared to the virtual route is included in the comparison travel distance in order to pass through the bypass road section of the detour factor feature In addition, a point that exceeds the detour factor feature in both the planned route and the virtual route, a point set on the detour factor feature, a point immediately before reaching the detour factor feature, etc. may be set as the predetermined reference point. it can.

For example, in the example shown in FIG. 4, when determining whether or not the river Ri is to be detoured as a candidate feature, it is possible to set the point N _ri2 as a point beyond the detour factor feature in the planned route. The second point N _vi2 can be a point that exceeds the detour factor feature in the virtual route. Further, it is possible to point set on the bypass factor feature at the midpoint of the expected path of the point N _ri1 and the point N _ri2, set the intersection Pi on the detour factors feature in a virtual path It can be a point. Further, the point N _ri1 can be a point immediately before reaching the detour factor feature in the planned route, and the first point N _vi1 can be a point immediately before reaching the detour factor feature. .

Furthermore, when the point immediately before reaching the detour factor feature is set as the reference point, the travel distance traveled to reach the vicinity of the passing road section from the departure point in the planned route is, for example, the route L shown in FIG. ₇ is the distance, traffic distance traffic to reach the first point set to the starting point side of the intersection from the starting point in the virtual path, for example, the distance of the path L ₁ shown in FIG. Therefore, a configuration may be adopted such that the ratio of the distance of the distance / path L ₁ of the path L ₇ is guided as the cause of the detour river Ri when it is more than a predetermined ratio. According to this configuration, since the travel distance is compared by excluding the factor after passing the detour factor feature, the increase rate of the travel distance can be directly evaluated.

  Furthermore, as a configuration for guiding the cause of the detour, a detour factor feature (or a combination of detour factor features) having the largest increase in the travel distance among the detour factor features that cause the detour. It is not limited to the structure which guides as a cause of a detour. For example, a configuration in which a detour factor feature (or a combination of detour factor features) whose travel distance increase rate is equal to or greater than a predetermined ratio is guided as a cause of detour, or the top M items having a large travel distance increase rate (M is It is possible to adopt a configuration that guides a detour factor feature (or a combination of detour factor features) of 2 or more integers as a cause of detour.

  Furthermore, when the increase rate of the travel distance is acquired, the increase rate of the travel distance may be acquired by a formula different from “scheduled passing distance / virtual passing distance”. For example, expressions such as “(scheduled passing distance−virtual passing distance) / virtual passing distance”, “scheduled passing distance−virtual passing distance”, and the like may be adopted. Of course, the predetermined ratio (threshold value) can be changed according to each expression.

  DESCRIPTION OF SYMBOLS 10 ... Navigation apparatus, 20 ... Control part, 21 ... Driving assistance program, 21a ... Intersection acquisition part, 21b ... Planned route acquisition part, 21c ... Guide part, 30 ... Recording medium, 30a ... Map information, 41 ... GPS receiving part, 42 ... Vehicle speed sensor, 43 ... Gyro sensor, 44 ... User I / F section

Claims (9)

An intersection acquisition means for acquiring an intersection of a straight line connecting the departure point and the destination point and a detour factor feature that can be passed only by at least one passing road section;
Planned route acquisition means for acquiring a planned route passing through the passing road section and arriving from the departure point to the destination point;
When the planned route is passed, the detour factor feature is guided as a cause of the detour when the travel distance increases by a predetermined ratio or more than the virtual route passing through the virtual road section set around the intersection. Guidance means to perform,
A driving support system comprising: The guiding means includes
A travel distance traveled to reach the destination from the departure point on the planned route;
A travel distance traveled to reach the destination from the departure point on the virtual route;
Guiding the detour feature as a cause of detour when the ratio is equal to or greater than the predetermined ratio,
The driving support system according to claim 1. The guiding means includes
A route from the departure point to the first point set on the departure point side with respect to the intersection point, and a straight line from the first point to the second point set on the destination point side with respect to the intersection point The virtual route is the sum of the route passing through the virtual road section and the route reaching the destination point from the second point,
The driving support system according to claim 2. The guiding means includes
A travel distance traveled to reach the periphery of the passing road section from the departure point in the planned route;
A travel distance for passing from the departure point to the first point set on the departure point side of the intersection in the virtual route;
Guiding the detour feature as a cause of detour when the ratio is equal to or greater than the predetermined ratio,
The driving support system according to claim 1. The guiding means includes
The route from the departure point to the first point is the virtual route,
The driving support system according to claim 4. The intersection acquisition means acquires the intersection for each of the plurality of bypass factor features when the straight line and the plurality of bypass factor features intersect,
The guide means passes through the virtual road section set for one bypass factor feature selected from a plurality of bypass factor features, and the passing road for the other bypass factor features The route passing through the section is the virtual route,
When the scheduled route is passed, among the detour factor features whose travel distance increases by a predetermined ratio or more than the virtual route, the detour factor feature having the largest increase in the travel distance is used as a cause of the detour. invite,
The driving support system according to claim 1. The intersection acquisition means acquires the intersection for each of the plurality of bypass factor features when the straight line and the plurality of bypass factor features intersect,
The guide means passes through the virtual road section set for two or more bypass factor features selected from a plurality of the bypass factor features, and for the other bypass factor features The route passing through the road section is the virtual route,
The combination of the detour factor features having the largest increase in the travel distance among the combinations of the detour factor features that increase the travel distance by a predetermined ratio or more when passing the planned route than the virtual route. As a cause of detours,
The driving support system according to claim 1. An intersection acquisition step of acquiring an intersection of a straight line connecting the departure point and the destination point and a detour factor feature that can be passed only by at least one passing road section;
A planned route acquisition step of acquiring a planned route passing from the starting point to the destination point through the passing road section;
When the planned route is passed, the detour factor feature is guided as a cause of the detour when the travel distance increases by a predetermined ratio or more than the virtual route passing through the virtual road section set around the intersection. A guidance process to perform,
Driving support method including. An intersection acquisition function for acquiring an intersection of a straight line connecting the starting point and the destination point and a detour factor feature that can be passed only by at least one passing road section;
A planned route acquisition function for acquiring a planned route that reaches the destination point from the departure point through the passing road section;
When the planned route is passed, the detour factor feature is guided as a cause of the detour when the travel distance increases by a predetermined ratio or more than the virtual route passing through the virtual road section set around the intersection. Guidance function to
Driving support program that realizes the computer.

Images