# Patent

## Title
Route evaluation device

## Abstract

Disclosed is a route evaluation device that enables traveling along a route in consideration of an operation of the driver of another vehicle, and can realize a safer traffic environment. A route evaluation device includes a route candidate generation section that generates route candidates of a host-vehicle, a route prediction section that predicts routes of another vehicle, a classification section that classifies the interference states of the route candidates of the host-vehicle and the predicted routes of another vehicle into a plurality of interference forms, and a route evaluation section that evaluates the routes of the host-vehicle on the basis of the interference forms classified by the classification section.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is the U.S. National Phase of PCT/JP2010/059995 filed Jun. 8, 2010, which claims priority of Japanese Patent Application P2009-141369 filed Jun. 12, 2009.
TECHNICAL FIELD
The present invention relates to a route evaluation device that generates a route of a host-vehicle for use at the time of traveling control of the host-vehicle.
BACKGROUND ART
In the related art, a risk acquisition device is known which detects a movable object in the vicinity of the host-vehicle, determines the possibility of collision of the movable object and the host-vehicle, and outputs the possibility of collision as the degree of risk. As a technique using the risk acquisition device, for example, a collision prevention device is known.
For example, Patent Document 1 (JP2009-20745A) describes a collision prevention device which calculates a plurality of possible routes of the host-vehicle and another vehicle in the vicinity of the host-vehicle on the basis of the traveling states of the host-vehicle and another vehicle, and calculates the best host-vehicle route collision probability (host-vehicle risk) on the basis of the routes. Further, in this collision prevention device, the best host-vehicle route collision probability (offset risk) is calculated on the basis of the possible route of the host-vehicle and the possible route of another vehicle which are calculated on the basis of the offset traveling state of the host-vehicle, which is offset from the traveling state of the host-vehicle.
CITATION LIST
Patent Literature


    
    
        [PTL 1] JP2009-20745A
    
    


SUMMARY OF INVENTION
Technical Problem
In addition to taking into consideration of the degree of risk as in the risk acquisition device of the related art, for example, it is preferable to generate a route in consideration of the driver of another vehicle such that the driver of another vehicle is not forced to take a sudden avoidance operation or braking operation due to traveling of the host-vehicle.
An object of the invention is to provide a route evaluation device that enables traveling along a route in consideration of an operation of the driver of another vehicle, and can realize a safer traffic environment.
Solution to Problem
An aspect of the invention provides a route evaluation device. The route evaluation device includes a route candidate generation unit that generates route candidates of a host-vehicle, a route prediction unit that predicts routes of another mobile object, a classification unit that classifies interference forms of the route candidates of the host-vehicle and the predicted routes of another mobile object into a plurality of interference forms, and a route evaluation unit that evaluates the route candidates of the host-vehicle on the basis of the interference forms classified by the classification unit.
The term “route” used herein refers to a concept including temporal elements, such as time and speed, and is different from the term “path” which does not include the concept of such temporal elements. The term “interference” refers to the host-vehicle and another vehicle crossing each other planarly in consideration of the vehicle width and the vehicle length.
With the route evaluation device according to the aspect of the invention, the interference forms of the route candidates of the host-vehicle and the predicted routes of another mobile object are classified into a plurality of interference forms on the basis of the patterns of a plurality of interference forms stored in advance. Therefore, an interference form occurring when the host-vehicle interferes with the route of another mobile object can be classified as one interference form, and the relevant route candidate can be highly evaluated as a route candidate to be avoided. As a result, it becomes possible to travel along a route in consideration of an operation of the drive of another vehicle, and a safer traffic environment can be realized.
In the route evaluation device according to the aspect of the invention, the classification unit may classify the interference forms on the basis of the behaviors of the host-vehicle and another mobile object until interference occurs. With this configuration, the classification unit can classify the interference forms taking into consideration whether the host-vehicle interferes with the route of another mobile object or another mobile object interferes with the route of the host-vehicle.
In the route evaluation device according to the aspect of the invention, the classification unit may classify the interference forms into at least an interference form in which the host-vehicle interferes with the route of another mobile object and an interference form in which another mobile object interferes with the route of the host-vehicle, and the route evaluation unit may highly evaluate the state, in which the host-vehicle interferes with the route of another mobile object, as a route to be avoided compared to the form in which another mobile object interferes with the route of the host-vehicle. With this configuration, interference occurring when the host-vehicle should avoid another mobile object can be avoided. As a result, it becomes possible to travel along a route in consideration of an operation of the driver of another vehicle, and a safer traffic environment can be realized.
Another aspect of the invention provides a route evaluation device. The route evaluation device includes a route candidate generation unit that generates route candidates of a host-vehicle, a route prediction unit that predicts routes of another mobile object, an objectivization unit that expresses interference forms of the route candidates of the host-vehicle and the predicted routes of another mobile object by objective numerical values, and a route evaluation unit that evaluates the route candidates of the host-vehicle on the basis of the numerical values expressed by the objectivization unit.
The term “route” used herein also refers to a concept including temporal elements, such as time and speed, and is different from the term “path” which does not include the concept of such temporal elements. In addition, similarly to the term “interference” described above, the term “interference” used herein refers to the host-vehicle and another vehicle crossing each other planarly in consideration of the vehicle width and the vehicle length. The objective numerical value of the interference state is calculated on the basis of the state of the host-vehicle or another vehicle (for example, position, speed, and direction).
With the route evaluation device according to another aspect of the invention, the interference state is numericalized in accordance with the prescribed rule of objective numericalization. Therefore, the interference form in which the host-Vehicle interferes with the route of another mobile object can be numericalized, and the relevant route candidate can be highly evaluated as a route candidate to be avoided. As a result, it becomes possible to travel along a route in consideration of an operation of the driver of another vehicle, and a safer traffic environment can be realized.
In the route evaluation device according to another aspect of the invention, the objectivization unit may express the interference forms by objective numerical values on the basis of the behaviors of the host-vehicle and another mobile object until interference occurs. Therefore, the classification unit can numericalize the interference forms taking into consideration whether the host-vehicle interferes with the route of another mobile object or another mobile object interferes with the route of the host-vehicle.
In the route evaluation device according to another aspect of the invention, the objectivization unit may calculate an interference ratio representing a probability that the host-vehicle interferes with the route of the mobile object, and the higher the interference ratio, the more highly the route evaluation unit may evaluate the relevant route as a route to be avoided. Therefore, interference occurring when the host-vehicle should avoid another vehicle can be avoided. As a result, it becomes possible to travel along a route in consideration of an operation of the driver of another vehicle, and a safer traffic environment can be realized.
According to the aspects of the invention, it becomes possible to travel along a route in consideration of an operation of the driver of another vehicle, and a safer traffic environment can be realized.



BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a block diagram showing the functional configuration of a traveling assist device including a route evaluation device according to an embodiment of the invention.
FIG. 2 is a diagram showing a route that is generated by a route candidate generation section and a route prediction section of FIG. 1.
FIG. 3 is a flowchart showing an operation in the traveling assist device of FIG. 1.
FIG. 4 is a diagram schematically showing a problem in a route prediction arithmetic operation of the related art.
FIG. 5 is a diagram schematically showing advantages of a route prediction arithmetic operation in an interference evaluation method of the traveling assist device of FIG. 1.
FIG. 6 is a diagram illustrating traveling control of a host-vehicle according to a traveling assist device of the related art.
FIG. 7 is a diagram illustrating traveling control of a host-vehicle according to the traveling assist device of FIG. 1.
FIG. 8 is a block diagram showing the functional configuration of a traveling assist device including a route evaluation device according to another embodiment of the invention.
FIG. 9 is a diagram showing a route that is generated by a route candidate generation section and a route prediction section of FIG. 8.
FIG. 10 is a diagram illustrating the criterion for classification of an interference state by a classification section of FIGS. 1 and 8.
FIG. 11 is a diagram illustrating the criterion for classification of an interference state by the classification section of FIGS. 1 and 8.
FIG. 12 is a diagram illustrating the criterion for classification of an interference state by the classification section of FIGS. 1 and 8.
FIG. 13 is a diagram illustrating the criterion for classification of an interference state by the classification section of FIGS. 1 and 8.
FIG. 14 is a diagram illustrating the criterion for classification of an interference state by the classification section of FIGS. 1 and 8.
FIG. 15 is a diagram illustrating the criterion for classification of an interference state by the classification section of FIGS. 1 and 8, together with FIG. 14.



DESCRIPTION OF EMBODIMENTS
Hereinafter, a traveling assist device 1 including a route evaluation device 60 according to a first embodiment of the invention will be described with reference to FIGS. 1 to 7. In the description of the drawings, the same parts are represented by the same reference numerals, and overlapping description thereof will be omitted. FIG. 1 is a block diagram showing the functional configuration of the traveling assist device 1 including the route evaluation device 60 according to this embodiment.
The traveling assist device 1 includes a vehicle state detection section 2, an environmental situation acquisition section 3, a vehicle control ECU (Electronic Control Unit) 6, and a traveling output section 9.
The vehicle state detection section 2 functions as vehicle state detection means for detecting position information and vehicle speed information of a vehicle, and uses, for example, a GPS (Global Positioning System), a wheel speed sensor, and the like. The GPS acquires position information of a vehicle. The wheel speed sensor is, for example, attached to each wheel of the vehicle, and acquires the wheel speed of the vehicle. The vehicle state detection section 2 is connected to the vehicle control ECU 6 and outputs acquired vehicle state information, such as position information and wheel speed information, to the vehicle control ECU 6.
The environmental situation acquisition section 3 functions as environmental situation acquisition means for acquiring environmental situation information regarding the vicinity of a host-vehicle 81, and uses, for example, a vehicle-to-vehicle communication device, a road-to-vehicle communication device, a radar sensor using millimeter waves or laser, and the like. Position information and vehicle speed information of another vehicle (another mobile object) 82 can be acquired by using a vehicle-to-vehicle communication device and a road-to-vehicle communication device. Position information and relative speed information of another vehicle 82 and an obstacle on a road can be acquired by using a millimeter-wave radar sensor or the like. The environmental situation acquisition section 3 is connected to the vehicle control ECU 6 and outputs acquired environmental situation information regarding the vicinity of the host-vehicle 81 to the vehicle control ECU 6.
The vehicle control ECU 6 performs overall control of the traveling assist device 1 and primarily includes, for example, a computer including a central processing unit CPU, a ROM, and a RAM, which are not shown. The vehicle control ECU 6 is connected to the vehicle state detection section 2, the environmental situation acquisition section 3, and the traveling output section 9. The vehicle control ECU 6 receives various kinds of information from the vehicle state detection section 2 and the environmental situation acquisition section 3, and outputs various kinds of information to the traveling output section 9. The vehicle control ECU 6 has a route evaluation device 60 including a route candidate generation section (route candidate generation unit) 61, a route prediction section (route prediction unit) 62, a classification section (classification unit) 63, and a route evaluation section (route evaluation unit) 64.
As shown in FIG. 2, the route candidate generation section 61 generates route candidates a1, a2 of the host-vehicle 81. The route candidate generation section 61 predicts the state of future position, speed, direction, and the like of the host-vehicle 81 from information regarding the position, speed, direction, and the like of the host-vehicle 81 input from the vehicle state detection section 2. The route candidate generation section 61 generates information regarding the predicted future state of the host-vehicle 81 as the route candidates a1 and a2, and outputs the generated route candidates a1 and a2 to the classification section 63.
As shown in FIG. 2, the route prediction section 62 predicts routes b1, b2, . . . , and bn of another mobile object, such as another vehicle 82, on the basis of the traveling environment. The route prediction section 62 predicts the state of future position, speed, direction, and the like of another mobile object from information regarding the position, speed, direction, and the like of another mobile object input from the environmental situation acquisition section 3. The route prediction section 62 predicts information regarding the predicted future state of another mobile object as the routes b1, b2, . . . , and bn, and outputs the predicted routes b1, b2, . . . , and bn to the classification section 63. In general, the routes b1, b2, . . . , and bn of another vehicle 82 are predicted exhaustively as compared with the ratite candidates of the host-vehicle 81.
The classification section 63 classifies the interference states of the route candidates a1 and a2 of the host-vehicle 81 generated by the route candidate generation section 61 and the predicted routes b1, b2, . . . , and bn of another mobile object predicted by the route prediction section 62 into a plurality of interference forms. Specifically, the classification section 63 classifies the interference forms into an interference form in which the host-vehicle 81 interferes with the route of another vehicle 82 and an interference form in which another vehicle 82 interferes with the route of the host-vehicle 81. In this case, the interference form in which the host-vehicle 81 interferes with the route of another vehicle 82 means an interference form occurring when the host-vehicle 81 should avoid another vehicle 82.
The route evaluation section 64 evaluates the route candidates a1 and a2 of the host-vehicle 81 on the basis of the interference forms classified by the classification section 63. Specifically, the route evaluation section 64 highly evaluates a route candidate classified by the classification section 63 as an interference form, in which the host-vehicle 81 interferes with the route of another vehicle 82, as a route that the host-vehicle 81 should avoid. For example, as shown in FIG. 2, with regard to the intersections between route candidates a1 and a2 of the host-vehicle and the predicted routes b1, b2, . . . , and b9 of another vehicle, the route evaluation section 64 determines whether the host-vehicle 81 interferes with the route of another vehicle 82 or another vehicle 82 interferes with the route of the host-vehicle 81. Next, with regard to the route candidates a1 and a2 generated by the route candidate generation section 61, when the interference states at the respective intersections have any intersection at which the host-vehicle 81 interferes with the route of the another vehicle 82, the route evaluation section 64 highly evaluates the relevant route candidate as a route that the host-vehicle 81 should avoid. In FIG. 2, O represents an intersection at which the host-vehicle 81 interferes with the route of another vehicle 82, and □ represents an intersection at which another vehicle 82 interferes with the route of the host-vehicle 81.
The route candidate generation section 61, the route prediction section 62, the classification section 63, and the route evaluation section 64 primarily constituting the route evaluation device 60 may be configured by loading a program on the computer or may be configured by separate hardware.
As shown in FIG. 1, the traveling output section 9 is connected to the vehicle control ECU 6. The traveling output section 9 receives a control signal of the vehicle control ECU 6 and carries out driving of the host-vehicle 81, for example, traveling drive, a braking operation, and a steering operation. For the traveling output section 9, for example, a traveling drive ECU that controls an actuator for adjusting the opening degree of a throttle valve of an engine, a braking ECU that controls a brake actuator for adjusting hydraulic brake pressure, a steering ECU that controls a steering actuator for providing steering torque, and the like are used. The traveling output section 9 carries out driving of the host-vehicle 81, for example, traveling drive, a braking operation, and a steering operation, in accordance with a route which is highly evaluated as a route, along which the host-vehicle 81 may travel, by the route evaluation section 64.
Next, the operation of the route evaluation device 60 will be described with reference to FIG. 3. FIG. 3 is a flowchart showing a flow of characteristic processing which is executed by the route evaluation device 60.
First, the vehicle state detection section 2 acquires the state (position, speed, and the like) of the host-vehicle 81 (S01). Then, the vehicle state detection section 2 outputs the acquired information to the vehicle control ECU 6.
Next, the environmental situation acquisition section 3 acquires the position and state of another object in the vicinity of the host-vehicle 81 (S02), and outputs the acquired information to the vehicle control ECU 6. Hereinafter, it is assumed that the position of another object is the value regarding the center of another object, and the state of another object is specified by the position, speed, and the like.
From a technical viewpoint, when an arithmetic operation is carried out to generate a trace in a subsequent step, it is important that a prediction arithmetic operation is terminated in a predetermined period, regardless of whether or not the host-vehicle 81 reaches a prescribed location (destination or an intermediate location similar to the destination). In general, there is no location on a road where safety is ensured in advance. For example, as shown in FIG. 4, when it is predicted that a host-vehicle O1 which is traveling on a three-lane road Rd sequentially reaches locations Q1, Q2, and Q3 set in advance, taking into consideration a case where the host-vehicle O1 substantially travels in a straight line along the same lane toward the set locations, if another vehicle O3 takes a route B3, another vehicle O2, may take a route B2 to avoid risk and may enter a lane on which the host-vehicle O1 is traveling. Thus, in the case of the route prediction arithmetic operation of the related art, it is not guaranteed in advance that the host-vehicle O1 is traveling safely toward the locations set in advance.
In this embodiment, since an optimum route is determined every time, instead of determining a location, such as a destination, to be reached by the host-vehicle O1 in advance, for example, a route B1 shown in FIG. 5 can be selected as the route of host-vehicle O1 under the same situation as in FIG. 4, and risk can be accurately avoided at the time of traveling of the host-vehicle O1, thereby ensuring safety.
Returning to FIG. 3, the route prediction section 62 predicts the future position and state of another object from information regarding the position and state of another object acquired by the environmental situation acquisition section 3, and predicts the routes b1, b2, . . . , and b9 of another object shown in FIG. 2 (S03). In the following description, description will be provided for a case where another object is another vehicle 82, but another object may be a person, an obstacle, or the like other than a vehicle.
Next, the route candidate generation section 61 predicts the future position and state of the host-vehicle 81 from information regarding the state of an object in the vicinity of the host-vehicle 81 acquired by the vehicle state detection section 2, and generates the route candidates a1 and a2 shown in FIG. 2 (S04). Specifically, the route candidate generation section 61 generates a temporal-spatial route constituted by time and space for each object. In generating the route, it is assumed that the total number of objects (including the host-vehicle 81) acquired by the environmental situation acquisition section 3 is K, and an arithmetic operation is carried out Nk times to generate a route for one object Ok (where 1≦k≦K, k is a natural number) (in this way, k and Nk are all natural numbers). It is also assumed that the time (trace generation time) for generating a route is T (>0). The route may be calculated by a known method, for example, a method described in Japanese Unexamined Patent Application Publication No. 2007-230454.
Next, the classification section 63 determines the interference states of the route candidates a1 and a2 of the host-vehicle 81 generated by the route candidate generation section 61 and the predicted routes b1, b2, . . . , and b9 of another mobile object predicted by the route prediction section 62 (S05). Specifically, as shown in FIG. 2, with regard to the intersections between the route candidates a1 and a2 of the host-vehicle 81 and the predicted routes b1, b2, . . . , and b9 of the another vehicle 82, it is determined whether the host-vehicle 81 interferes with the route of another vehicle 82 or another vehicle 82 interferes with the route of the host-vehicle 81. When the classification section 63 classifies the interference states, any classification method in consideration of another vehicle may be used. For example, classification based on the mechanical conditions of smoothness (curvature, acceleration/deceleration, and the like) of a route immediately before interference, classification based on the social norms, such as the observance level of the traffic rules or manners, the fault proportion of automobile insurance, and the judicial precedents, classification (paying closer attention to a bicycle and a small vehicle) in consideration of vehicle performance, and the like may be used.
Next, the classification section 63 classifies the route candidates by interference forms on the basis of the interference states determined in S05 (S06). Here, the route candidates are classified into “an interference form in which the host-vehicle 81 interferes with the route of another vehicle” and “an interference form in which another vehicle 82 interferes with the route of the host-vehicle”. As shown in FIG. 2, when one of the route candidates a1 and a2 has any intersection (indicated by O in FIG. 2) where the host-vehicle 81 interferes with another vehicle, the classification section 63 classifies the relevant route candidate as “the interference form in which the host-vehicle 81 interferes with the route of another vehicle”. Referring to FIG. 2, the route candidate a1 has an intersection (indicated by O in FIG. 2) where the host-vehicle 81 interferes with the route of another vehicle, such that the route candidate a1 is classified into “the interference form in which the host-vehicle 81 interferes with the route of another vehicle”. Meanwhile, the route candidate a2 has only an intersection (indicated by □ in FIG. 2) where another vehicle 82 interferes with the route of the host-vehicle but has no intersection (indicated by O in FIG. 2) where the host-vehicle 81 interferes with the route of another vehicle, such that the route candidate a2 is classified into “the interference form in which another vehicle 82 interferes with the route of the host-vehicle”. In this case, no route candidate has “the interference form in which another vehicle 82 interferes with the route of the host-vehicle” (S06: NO), the process returns to Step S04, and route candidates are generated again (S04).
Next, in Step S06, when the route candidates a1 or a2 have “the interference form in which another vehicle 82 interferes with the route of host-vehicle” (S06: YES), the route evaluation section 64 highly evaluates the relevant route candidate as a route that the host-vehicle 81 should travel (S07). Then, the traveling output section 9 carries out driving of the host-vehicle 81, for example, traveling drive, a braking operation, and a steering operation, in accordance with a route which is highly evaluated as a route, along which the host-vehicle 81 may travel, by the route evaluation section 64 (S08).
As described above, according to the traveling assist device 1 of this embodiment, the classification section 63 classifies the interference forms on the basis of a plurality of interference forms stored in advance, and the route evaluation section 64 evaluates the route candidates on the basis of the classification result. Therefore, an interference form in which the host-vehicle 81 interferes with the route of another vehicle 82 can be classified as one interference form, and the relevant route candidate can be highly evaluated as a route candidate to be avoided. As a result, it becomes possible to travel along a route in consideration of an operation of the driver of another vehicle 82, and a safer traffic environment can be realized.
With regard to traveling control when a vehicle enters a main road 90 continuously with another vehicle 82a at a T-junction, the effects of the traveling assist device 1 of this embodiment will be described with reference to FIGS. 6 and 7.
According to the traveling assist device of the related art, traveling control of the host-vehicle 81 is carried out in accordance with a route which is determined to be low risk, regardless of the interference forms of the route candidates of the host-vehicle and the predicted routes of another vehicle. For this reason, when the degree of risk is low, for example, as shown in FIG. 6, even when a route along which the host-vehicle 81 enters the main road 90 interferes with the route of another vehicle 82a, traveling control is carried out to allow the host-vehicle 81 to enter the main road 90. In this case, the movement of the host-vehicle 81 causes interference with the route of another vehicle 82a, that is, interference occurring when the host-vehicle 81 should avoid another vehicle 82a. For this reason, the driver of another vehicle 82a may be forced to take a sudden avoidance operation or braking operation.
Meanwhile, according to the traveling assist device 1 of this embodiment, with regard to a plurality of route candidates, even when it is determined that the route along which the vehicle enters the main road 90 is lowest risk, if the classification section 63 classifies the relevant route into “interference form in which the host-vehicle 81 interferes with the route of another vehicle”, the route evaluation section 64 highly evaluates the relevant route as a route that the host-vehicle 81 should avoid. Then, the route evaluation section 64 highly evaluates a route, which is classified as “the interference form in which another vehicle 82b interferes with the route of the host-vehicle” by the classification section 63, that is, as shown in FIG. 7, a route along which the vehicle does not enter the main road 90 as a route that the host-vehicle 81 should travel. Therefore, interference occurring when the host-vehicle 81 should avoid another vehicle 82a can be avoided. As a result, it becomes possible to travel along a route in consideration of an operation of the driver of another vehicle 82a, and a safer traffic environment can be realized. Meanwhile, another vehicle 82b encounters interference occurring when another vehicle 82b should avoid the host-vehicle 81, such that another vehicle 82b can avoid interference in cooperation with the host-vehicle 81.
Although the embodiment of the invention has been described, the invention is not limited to the above-described embodiment, and various modifications or changes may be made without departing from the scope of the invention.
Although in the foregoing embodiment, as shown in FIG. 1, the example where the route evaluation device 60 includes the route candidate generation section 61, the route prediction section 62, the classification section 63, and the route evaluation section 64 has been described, the invention is not limited thereto. For example, as shown in FIG. 8, a route evaluation device 65 may include a route candidate generation section 61, a route prediction section 62, an objectivization section (objectivization unit) 66, and a route evaluation section (route evaluation unit) 67. The route candidate generation section 61 and the route prediction section 62 are the same as those in the route evaluation device 60 of the foregoing embodiment, and thus description thereof will not be repeated.
As shown in FIG. 9, the objectivization section 66 expresses the interference states of route candidates a11, a12, and a13 of the host-vehicle 81 generated by the route candidate generation section 61 and predicted routes b11, b12, . . . , and b20 of another vehicle 82 predicted by the route prediction section 62 by objective numerical values. Specifically, the objectivization section 66 calculates an another-vehicle interference ratio. The term “another-vehicle interference ratio” refers to the ratio of intersections (indicated by O in FIG. 9) where the host-vehicle 81 interferes with the route of another vehicle from among all the intersections of the route candidates a11, a12, and a13 and the predicted routes b11, b12, . . . , and b20. Referring to FIG. 9, the route candidate a11 has 10 intersections in total and has eight intersections (indicated by O in FIG. 9) where the host-vehicle 81 interferes with the route of another vehicle, such that the another-vehicle interference ratio becomes 80%. Similarly, the another-vehicle interference ratio of the route candidate a12 becomes 50%, and the another-vehicle interference ratio of the route candidate a13 becomes 0%.
The route evaluation section 67 evaluates the route of the host-vehicle 81 on the basis of the numerical values expressed by the objectivization section 66. Specifically, the route evaluation section 64 highly evaluates a route candidate having a low another-vehicle interference ratio expressed by the objectivization section 66 as a route that the host-vehicle 81 should travel. For example, the route evaluation section 67 highly evaluates a route candidate having an another-vehicle interference ratio equal to or smaller than 20% as a route that the host-vehicle 81 should travel. The critical value of the another-vehicle interference ratio may be appropriately set.
According to the route evaluation device 65 of this embodiment, the interference forms are numericalized in accordance with the prescribed rule of objective numericalization. Therefore, an interference form in which the host-vehicle 81 interferes with the route of another vehicle can be specified, and the relevant route candidate can be highly evaluated as a route candidate to be avoided. As a result, traveling along a route in consideration of an operation of the driver of another vehicle 82, and a safer traffic environment can be realized.
As shown in FIG. 8, the traveling assist device 1 may further include a display section 8. The display section 8 is means for displaying the contents of the route candidates evaluated by the route evaluation section 67, and for example, displays the contents on a monitor or projects the contents onto a windscreen. Specifically, the display section 8 displays a route specified as “the interference form in which another vehicle interferes with the route of the host-vehicle” and a route specified as “the interference form in which the host-vehicle interferes with the route of another vehicle” based on the evaluation of the route candidates by the route evaluation section 67 with different colors. Therefore, it is possible to display for the driver a route that the host-vehicle should travel or a route that the host-vehicle should avoid.
The traveling assist device 1 may have the display section 8 but may not have the traveling output section 9. In this case, it is possible for the driver to recognize a route specified as “the interference form in which another vehicle interferes with the route of the host-vehicle”. In this case, the driver can control the host-vehicle in accordance with a route displayed on the display section 8. As a result, it becomes possible to travel of the host-vehicle 81 along a route in consideration of an operation of the driver of another vehicle 82, and a safer traffic environment can be realized.
In the traveling assist device 1 of the foregoing embodiment, when the classification section 63 classifies the interference states, any classification method in consideration of another vehicle may be used, and for example, classification based on the mechanical conditions of smoothness (curvature, acceleration/deceleration, and the like) of a route immediately before interference, classification based on the social norms, such as the observance level of the traffic rules or manners, the fault proportion of automobile insurance, and the judicial precedents, classification (paying closer attention to a bicycle and a small vehicle) in consideration of vehicle performance, and the like may be used. Hereinafter, the method of classifying the interference states by the classification section 63 will be described in detail.
For example, as shown in FIG. 10, it may be determined whether the host-vehicle 81 is likely to interfere with the route of another vehicle 82 or not on the basis of an angle α between the direction of the host-vehicle 81 and the traveling direction of a region A1 where the host-vehicle 81 is located. For example, when the angle α between the direction of the host-vehicle 81 and the traveling direction of the region A1 where the host-vehicle 81 is present is equal to or greater than a predetermined angle (for example, 45°), it may be determined that the host-vehicle 81 interferes with the route of another vehicle 82.
For example, as shown in FIG. 11, it may be determined whether the host-vehicle 81 is likely to interfere with the route of another vehicle 82 or not on the basis of the priorities of a region A3 where the host-vehicle 81 is located and a region A2 where another vehicle 82 is located. For example, when the region A3 where the host-vehicle 81 is located has a priority lower than the region A2 where another vehicle 82 is located, it may be determined that the host-vehicle 81 interferes with the route of another vehicle 82. In comparison of the priorities of the region A3 where the host-vehicle 81 is located and the region A2 where another vehicle 82 is located, at an intersection shown in FIG. 12, it may be determined that the host-vehicle 81 is likely to interfere with the route of another vehicle 82. The priority based on signal information as well as the priority based on the region where the host-vehicle 81 is located may be used. For example, a vehicle which runs into a green light has high priority, and a vehicle which runs into a red light has low priority.
For example, as shown in FIG. 13, it may be determined whether the host-vehicle 81 is likely to interfere with the route of another vehicle 82 or not on the basis of road markings 91 and 92. When the road marking 91 is a white line and the road marking 92 is a yellow line, if the host-vehicle 81 which is traveling in a region A1 changes lane to a region A2, the host-vehicle 81 is violating the traffic rules. With regard to traveling which violates the traffic rules, it may be determined that the host-vehicle 81 interferes with the route of another vehicle 82. For the determination regarding violation of the traffic rules, road signs as well as road markings may be used.
For example, as shown in FIG. 14, it may be determined whether the host-vehicle 81 is likely to interfere with the route of another vehicle 82 or not by using the parts where the host-vehicle 81 and another vehicle 82 interfere with each other. In FIG. 14, “A” indicates that the host-vehicle 81 interferes with the route of another vehicle 82, and “B” indicates that another vehicle 82 interferes with the route of the host-vehicle 81. For example, as shown in FIG. 15, when the front surface of the host-vehicle 81 in the traveling direction and the side surface of another vehicle 82 in the traveling direction interfere with each other, as shown in FIG. 14, it may be determined that the host-vehicle 81 interferes with the route of another vehicle 82.
INDUSTRIAL APPLICABILITY
According to the invention, it is possible to travel along a route in consideration of an operation of the driver of another vehicle, and can realize a safer traffic environment.

## Claims

1. A route evaluation device comprising:
an electronic control unit including a central processing unit, the electronic control unit configured to:
generate a plurality of route candidates of a host-vehicle on the basis of an input from a vehicle state detection section;
predict a plurality of routes of another mobile object on the basis of an input from an environmental situation acquisition section;
calculate a plurality of intersections of each of the plurality of route candidates of the host-vehicle with the plurality of routes of another mobile object;
determine whether the host-vehicle interferes with the route of another mobile object or another mobile object interferes with the route of the host-vehicle for the plurality of intersections, on the basis of an angle between the direction of the host-vehicle and a traveling direction of a region where the host-vehicle is located and a region where another mobile object is located, priority based on signal information, violation of traffic rules, or parts whether the host-vehicle and another mobile object interfere with each other;
calculate a ratio of (a) to (b), wherein (a) is the number of intersections where the host-vehicle interferes with the route of another mobile object of each of the plurality of route candidates of the host-vehicle and (b) is the number of all intersections of each of the plurality of route candidates of the host-vehicle;
select a route candidate, which as the lowest ratio, as the route that the host-vehicle should travel; and
send the selected route to at least one of a travel output section carrying out driving and a display section in which the selected route is displayed on the display section.

2. The route evaluation device according to claim 1, wherein the electronic control unit is configured to select a route candidate, which has no intersection where the host-vehicle interferes with the route of another mobile object, as the route that the host-vehicle should travel.