Driving assist system

Abstract

To provide a driving assist system capable of notifying a rider of a motor-bicycle that can travel on a road shoulder that there is a vehicle behind with an appropriate strength.SOLUTION: A driving assist system 1 comprises: a surrounding information acquisition unit 81 that acquires surrounding information related to a state around a self-vehicle, which is a motor-bicycle; a notification target recognition unit 85 that recognizes a vehicle behind present in a notification region defined behind the self-vehicle as a notification target on the basis of the surrounding information; a notification control unit 86 that performs first notification control, which notifies a rider of the self vehicle of the presence of the notification target, if the notification target is recognized; and a course change prediction unit 87 that predicts execution of a course change by the self-vehicle while the notification target is being recognized on the basis of the surrounding information. The notification control unit 86 performs a second notification control with a notification strength higher than that of the first notification control if execution of a course change is predicted by the course change prediction unit 87 during the execution of the first notification control.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a driving assistance system, and more particularly to a driving assistance system having a function of notifying an occupant of the presence of another vehicle to the rear side of a vehicle. [Background technology]

[0002] In recent years, efforts to provide access to sustainable transport systems that take into consideration vulnerable transport participants have been gaining momentum. To achieve this, we are focusing on research and development into various driver assistance functions to further improve road safety and convenience.

[0003] The vehicle control device described in Patent Document 1, when recognizing the presence of another vehicle within a predetermined area defined behind the vehicle based on information acquired by a camera, radar, etc., can prompt the occupant to recognize the other vehicle approaching the vehicle by displaying a predetermined image on a part of the mirror surface of the door mirror. Such a driving assistance function is also called a BSI (Blind Spot Information) function.

[0004] Recently, a BSI function that issues a warning in two stages is also known. In this case, a weak warning is issued first when a vehicle approaching from the rear side of the vehicle is detected, and then a strong warning is issued when the vehicle occupant operates the turn signal to indicate an intention to change lanes. This prevents the occupant from changing lanes to the other vehicle approaching from the rear side without recognizing the presence of the other vehicle. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2019-49774 A Summary of the Invention [Problem to be solved by the invention]

[0006] Fig. 8 is a diagram showing a state in which the host vehicle V, which is a motorcycle traveling on a two-lane road 200, is about to overtake a leading vehicle Va, which is a four-wheeled automobile. Fig. 8 also shows a case in which a following vehicle Vb, which is also a motorcycle, is traveling on the rear side of the host vehicle V and on the shoulder 209 of the road 200.

[0007] As shown in Fig. 8, motorcycles (e.g., the host vehicle V and the following vehicle Vb in Fig. 8) are narrower and lighter than four-wheeled automobiles (e.g., the leading vehicle Va in Fig. 8), and therefore can travel on the shoulder 209. As shown by the arrow in Fig. 8, the host vehicle V, which is a motorcycle, can overtake the leading vehicle Va from the shoulder 209. However, because the overtaking action of the host vehicle V as shown in Fig. 8 is not a lane change, the occupant of the host vehicle V may change course to the shoulder 209 without operating the turn signal.

[0008] However, in the conventional BSI function, a strong warning is issued only when the turn signal is operated, as described above. Therefore, in the example shown in Fig. 8, even if the following vehicle Vb is recognized as a target for warning by the BSI function installed in the vehicle V, a strong warning is not issued, so there is a risk of contact between the following vehicle Vb traveling on the shoulder 209 and the vehicle V attempting to enter the shoulder 209.

[0009] An object of the present invention is to provide a driving assistance system that can improve traffic safety by notifying occupants of a vehicle that is capable of driving on the shoulder of the road of the presence of a following vehicle with an appropriate intensity. [Means for solving the problem]

[0010] (1) The driving assistance system of the present invention comprises a surrounding information acquisition means for acquiring surrounding information regarding the conditions around the vehicle; a notification object recognition means for recognizing another vehicle present within a notification area defined to the rear side of the vehicle as a notification object based on the surrounding information; a notification control means for performing a first notification control to notify an occupant of the vehicle of the presence of the notification object when the notification object is recognized; and a course change prediction means for predicting, based on the surrounding information, that the vehicle will change course while the notification object is recognized, wherein the notification control means performs a second notification control having a higher notification intensity than the first notification control when the course change prediction means predicts that the lane change will be performed while the first notification control is being performed.

[0011] (2) In this case, it is preferable that the lane change prediction means predicts the execution of the lane change when it recognizes, based on the surrounding information, the presence of a movement-inducing factor ahead of the vehicle in the direction of travel of the vehicle that will cause movement along the width direction of the vehicle.

[0012] (3) In this case, the driving assistance system divides the road on which the vehicle is traveling into a shoulder area within a predetermined width from the widthwise end and a normal driving area adjacent to the shoulder area, and further includes a driving position identification means for identifying the driving position of the vehicle on the road, and it is preferable that the lane change prediction means predicts that the vehicle will change course from the shoulder area to the normal driving area when it recognizes that the driving position is the shoulder area and that an obstacle is present ahead of the vehicle in the direction of travel as the movement-causing factor.

[0013] (4) In this case, the driving assistance system further includes a driving position identification means for dividing the road on which the vehicle is traveling into a shoulder area within a predetermined width from the widthwise end and a normal driving area adjacent to the shoulder area, and for identifying the driving position of the vehicle on the road, and a risk index calculation means for calculating a risk index based on the surrounding information when a leading vehicle is present ahead of the vehicle in the direction of travel, which becomes smaller as the risk of the vehicle contacting the leading vehicle increases, and it is preferable that the lane change prediction means predicts the execution of the lane change when the driving position is in the normal driving area, the leading vehicle is present ahead of the vehicle in the direction of travel as the movement causing factor, and the risk index for the leading vehicle is below a predetermined threshold.

[0014] (5) In this case, the driving assistance system divides the road on which the vehicle is traveling into a shoulder area within a predetermined width from the widthwise end and a normal driving area adjacent to the shoulder area, and further includes a driving position identification means for identifying the driving position of the vehicle on the road, and it is preferable that the lane change prediction means predicts the execution of the lane change when the driving position is the normal driving area, a preceding vehicle and a traffic light are present ahead of the vehicle in the direction of travel as the movement-causing factors, and the display mode of the traffic light indicates no entry or stop.

[0015] (6) In this case, the driving assistance system divides the road on which the vehicle is traveling into a shoulder area within a predetermined width from the widthwise end and a normal driving area adjacent to the shoulder area, and further includes a driving position identification means for identifying the driving position of the vehicle on the road, and it is preferable that the lane change prediction means predicts the execution of the lane change when the driving position is in the normal driving area, a leading vehicle is present ahead of the vehicle in the direction of travel as the movement-causing factor, and the brake lights of the leading vehicle are on.

[0016] (7) In this case, the driving assistance system divides the road on which the vehicle is traveling into a shoulder area within a predetermined width from the widthwise end and a normal driving area adjacent to the shoulder area, and further includes a driving position identification means for identifying the driving position of the vehicle on the road, and it is preferable that the lane change prediction means predicts the execution of the lane change when the driving position is in the normal driving area, a leading vehicle is present ahead of the vehicle in the direction of travel as the movement causing factor, and the turn signal of the leading vehicle is on.

[0017] (8) In this case, when two or more lanes are defined in the normal driving area, it is preferable that the notification object recognition means changes the length along the width direction of the notification area depending on the driving position.

[0018] (9) In this case, it is preferable that the notification target recognition means shortens the length along the width direction of the notification area when the driving position is in the shoulder area or when the driving position is at the edge of each lane, compared to when the driving position is in the center of each lane.

[0019] (10) In this case, the driving assistance system divides the road on which the vehicle is traveling into a shoulder area within a predetermined width from the widthwise end and a normal driving area adjacent to the shoulder area, and further includes a driving position identification means for identifying the driving position of the vehicle on the road, and it is preferable that the lane change prediction means predicts that the vehicle will not change course from the normal driving area to the shoulder area when the vehicle is within the normal driving area and traveling continuously for a predetermined time or more within a predetermined distance from a line dividing the shoulder area and the normal driving area.

[0020] (11) In this case, it is preferable that the driving assistance system further includes a driving position learning means for learning the driving position of the vehicle in the road width direction, and the lane change prediction means predicts the execution of the lane change based on the surrounding information and the learning result of the driving position learning means.

[0021] (12) In this case, it is preferable that the host vehicle is a saddle-ride type vehicle. Effect of the Invention

[0022] (1) In the driving assistance system according to the present invention, the surrounding information acquisition means acquires surrounding information on the state of the surroundings of the vehicle, the notification object recognition means recognizes another vehicle existing in a notification area defined on the rear side of the vehicle as a notification object, and the notification control means performs a first notification control to notify the occupant of the vehicle of the presence of the notification object. The lane change prediction means predicts the execution of a lane change by the vehicle while the notification object is recognized based on the surrounding information. Here, if the vehicle is capable of traveling on the shoulder of the road, such as a motorcycle, the occupant of the vehicle may enter or exit the shoulder of the road without activating the turn signal, as described above. In contrast, in the present invention, the notification control means performs a second notification control with a higher notification intensity than the first notification control when a lane change is predicted based on the surrounding information while the first notification control is being performed, i.e., while the presence of the notification object is being recognized. As a result, according to the present invention, if an occupant of the vehicle attempts to change course without recognizing the presence of the object to be notified and without activating the turn signal, the notification control means performs a second notification control with high notification intensity, so that the occupant of the vehicle can recognize the presence of the object to be notified before actually changing the course of the vehicle body, thereby improving traffic safety.

[0023] (2) In the present invention, when the lane change prediction means recognizes the presence of a movement inducing factor that causes movement along the width direction of the vehicle in the forward direction of the vehicle based on the surrounding information, the lane change prediction means predicts that the vehicle will change lane. Therefore, according to the present invention, the second notification control can be performed before the vehicle body of the vehicle actually starts a lane change operation, so that a sufficient time can be secured for the occupant to check the surrounding situation and determine whether or not to change lane.

[0024] (3) In the present invention, when the lane change prediction means recognizes that the vehicle is traveling in a road shoulder area and that an obstacle exists ahead of the vehicle in the traveling direction as a movement inducing factor, the lane change prediction means predicts that the vehicle will change course from the road shoulder area to a normal traveling area. Therefore, according to the present invention, the second notification control can be performed before the vehicle body actually starts a lane change operation to avoid contact with the obstacle ahead, so that a sufficient time can be secured for the occupant to check the surrounding situation and determine whether or not to execute the lane change.

[0025] (4) In the present invention, the course change prediction means predicts that the host vehicle will change course to avoid contact with the vehicle ahead when the host vehicle is in a normal driving area, a vehicle ahead exists as a movement trigger in the traveling direction of the host vehicle, and the risk index for the vehicle ahead is equal to or lower than a predetermined threshold. Therefore, according to the present invention, the second notification control can be performed before the vehicle body of the host vehicle actually starts a course change operation to avoid contact with the vehicle ahead, so that a sufficient time can be secured for the occupant to determine whether or not to change course while checking the surrounding situation.

[0026] (5) In the present invention, the lane change prediction means predicts that the host vehicle will change lane when the host vehicle is in a normal driving area, there is a preceding vehicle and a traffic light ahead of the host vehicle in the traveling direction as a movement inducing factor, and the display mode of the traffic light indicates a no entry or stop. Therefore, according to the present invention, the second notification control can be performed before the host vehicle actually starts a lane change operation to avoid contact with the preceding vehicle that is trying to stop, so that the occupant can have enough time to check the surrounding situation and determine whether or not to change lane.

[0027] (6) In the present invention, the lane change prediction means predicts that the host vehicle will change lane when the host vehicle is in a normal driving area, there is a leading vehicle ahead of the host vehicle in the traveling direction as a movement inducing factor, and the leading vehicle has its brake lights on. Therefore, according to the present invention, the second notification control can be performed before the host vehicle actually starts a lane change operation to avoid contact with the leading vehicle that is trying to stop, so that the occupant can have enough time to check the surrounding situation and determine whether or not to change lane.

[0028] (7) In the present invention, the lane change prediction means predicts that the host vehicle will change lane when the host vehicle is in a normal driving area, there is a leading vehicle ahead of the host vehicle in the traveling direction as a movement inducing factor, and the direction indicator of the leading vehicle is on. Therefore, according to the present invention, the second notification control can be performed before the host vehicle actually starts a lane change operation to avoid contact with the leading vehicle that is trying to change lane, so that the occupant can have enough time to check the surrounding situation and determine whether or not to change lane.

[0029] (8) Here, a case where the road on which the vehicle is traveling has two lanes on one side, that is, the road on which the vehicle is traveling is divided into a first lane, a second lane, and a shoulder area from the center divider side by at least two dividing lines is considered. On such a road with two lanes on one side, the possibility that a vehicle traveling in the shoulder area or near the shoulder area of ​​the second lane will change course to the first lane is considered to be lower than the possibility that a vehicle traveling in the center of the second lane will change course to the first lane. For this reason, if the width direction length of the notification area is made equal for a vehicle traveling in the shoulder area or near the shoulder area of ​​the second lane and a vehicle traveling in the center of the second lane, the vehicle traveling in the first lane may be recognized as a notification target even though it is traveling in the shoulder area or near the shoulder area of ​​the second lane, which may annoy the occupants. Therefore, in the present invention, when two or more lanes are divided in the normal traveling area, the length along the width direction of the notification area is changed according to the traveling position of the vehicle. This makes it possible to prevent the passenger from feeling annoyed by frequent notifications being issued.

[0030] (9) According to the present invention, the notification target recognition means shortens the length along the width of the notification area when the driving position is in a shoulder area or at the edge of each lane compared to when the driving position is in the center of each lane, thereby preventing frequent notifications from being issued, which may annoy occupants.

[0031] (10) In the present invention, when the vehicle is in the normal driving area and continues to drive within a predetermined distance from the line dividing the shoulder area and the normal driving area for a predetermined time or more, the course change prediction means determines that the occupant of the vehicle has no intention of entering the shoulder area and predicts that the vehicle will not change course from the normal driving area to the shoulder area. Therefore, according to the present invention, it is possible to prevent the occupant from feeling annoyed by the frequent second notification control being performed for the occupant who has no intention of driving in the shoulder area.

[0032] (11) In the present invention, the traveling position learning means learns the traveling position of the vehicle in the road width direction, and the course change prediction means predicts the execution of a course change based on surrounding information and the learning result of the traveling position learning means. Therefore, according to the present invention, since the execution of a course change can be predicted taking into account the tendency of the past traveling position, the timing of executing the second notification control can be made suitable for the occupant.

[0033] (12) Saddle-type vehicles such as motorcycles and buggies are narrower and lighter than four-wheeled automobiles, and therefore may enter or exit the road shoulder without activating the turn signal. Therefore, according to the present invention, the first and second notification controls are performed for such saddle-type vehicles in the above-described procedure, thereby improving traffic safety. [Brief description of the drawings]

[0034] [Figure 1] 1 is a diagram showing a configuration of a driving assistance system according to an embodiment of the present invention; [Figure 2A] 13A and 13B are diagrams showing an example of a warning image displayed when another vehicle reflected in the mirror surface of the right side mirror is set as a notification target. [Figure 2B] 2B is a diagram showing a schematic diagram of a case where the warning image shown in FIG. 2A is blinked. FIG. [Diagram 3] FIG. 4 is a diagram showing an example of a travelable range identified by a travel position identification unit; [Figure 4A] 10 is a diagram showing a schematic configuration of a right side notification area and a left side notification area that are defined when traveling near the center of the second lane of a two-lane road. FIG. [Figure 4B] 10 is a diagram showing a schematic configuration of a right side notification area and a left side notification area that are defined when traveling near a second dividing line of the second lane of a two-lane road. FIG. [Figure 4C] 10 is a diagram showing a schematic configuration of a right side notification area and a left side notification area that are defined when traveling on a two-lane road near a first dividing line of the second lane. FIG. [Figure 5A]10 is a diagram showing a schematic configuration of a right side notification area and a left side notification area that are defined when traveling near the center of the second lane of a road with three lanes in each direction; FIG. [Figure 5B] 10 is a diagram showing a schematic configuration of a right side notification area and a left side notification area that are defined when traveling near a second dividing line of the second lane on a road with three lanes in each direction; FIG. [Figure 5C] 10 is a diagram showing a schematic configuration of a right side notification area and a left side notification area that are defined when traveling on a road with three lanes in each direction and close to a first dividing line of the second lane. FIG. [Figure 6A] FIG. 11 is a diagram showing a first example of a movement triggering factor. [Figure 6B] FIG. 11 is a diagram showing a second example of a movement triggering factor. [Figure 6C] FIG. 13 is a diagram showing a third example of a movement inducing factor. [Figure 6D] FIG. 13 is a diagram showing a fourth example of a movement inducing factor. [Figure 6E] FIG. 13 is a diagram showing a fifth example of a movement triggering factor. [Figure 6F] FIG. 13 is a diagram showing a sixth example of a movement triggering factor. [Figure 7A] 10 is a flowchart showing a specific procedure of a notification process (part 1). [Figure 7B] 13 is a flowchart showing a specific procedure of the notification process (part 2). [Figure 8] FIG. 1 is a diagram showing a state in which a vehicle traveling on a two-lane road is about to overtake a vehicle ahead. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] Hereinafter, a driving assistance system according to an embodiment of the present invention will be described with reference to the drawings.

[0036] FIG. 1 is a diagram showing the configuration of a driving assistance system 1 according to this embodiment. This driving assistance system 1 is mounted on a vehicle (not shown). In the following, the driving assistance system 1 is mounted on a saddle-type vehicle, more specifically, a motorcycle, which is narrower and lighter than a four-wheeled automobile, but the present invention is not limited to this. The driving assistance system 1 may be mounted on a four-wheeled automobile, in addition to a saddle-type three-wheeled vehicle, a saddle-type four-wheeled vehicle, and a saddle-type vehicle such as a motorized bicycle. The driving source of the motorcycle may be an internal combustion engine, a rotating electric machine, or a combination of these. The power source of the rotating electric machine may be a secondary battery, a capacitor, or a fuel cell.

[0037] The driving assistance system 1 assists a rider in safe driving of a motorcycle. Among various driving assistance functions realized by the driving assistance system 1, the so-called BSI function that notifies the rider of the presence of another vehicle approaching from the rear side, which is a blind spot for the rider, will be described below.

[0038] The driving assistance system 1 includes an external sensor unit 2, a vehicle speed sensor 3, turn signal switches 4L, 4R, a braking device 5, turn signals 6L, 6R, a BSI indicator 7, a driving assistance control device 8, and side mirrors 9L, 9R.

[0039] The external sensor unit 2 is composed of a plurality of on-board sensors, such as a front camera unit and a rear radar unit, that acquire information about the surroundings of the vehicle.

[0040] The front camera unit includes a digital camera using a solid-state image sensor such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). The front camera unit is attached to an arbitrary position (for example, the front windshield or the mirror) of the front part of the vehicle body while facing forward in the traveling direction of the vehicle. The rear radar unit includes a millimeter wave radar that detects an object by measuring the reflected wave from the object in response to the millimeter wave irradiation. The rear radar unit is provided at an arbitrary position (for example, near the tail lamp and near the turn indicators on both the left and right sides) of the rear part of the vehicle body while facing backward in the traveling direction of the vehicle body, and detects objects on the rear side (right rear and left rear) of the vehicle body. Data obtained by the front camera unit, the rear radar unit, etc. is transmitted to the driving assistance control device 8.

[0041] The vehicle speed sensor 3 detects the moving speed along the traveling direction of the vehicle body (hereinafter referred to as "vehicle speed") and transmits a signal corresponding to the detected vehicle speed to the driving assistance control device 8. For this vehicle speed sensor 3, for example, a rotary encoder that outputs a signal corresponding to the rotation speed of rear wheels (not shown) is used.

[0042] The left turn indicator switch 4L and the right turn indicator switch 4R are controls that the rider can operate to inform surrounding traffic participants (hereinafter also referred to as "surrounding traffic participants") such as oncoming vehicles and following vehicles of the traveling direction of the vehicle body, and are provided, for example, at the base of the left handlebar grip that the rider holds with his left hand. When the rider turns on the left turn indicator switch 4L, a turn indicator drive circuit (not shown) activates (i.e., blinks) the left turn indicator 6L provided on the left side of the vehicle body as seen by the rider. When the rider turns on the right turn indicator switch 4R, the turn indicator drive circuit activates (i.e., blinks) the right turn indicator 6R provided on the right side of the vehicle body as seen by the rider.

[0043] The brake device 5 includes, for example, a brake caliper, a cylinder that transmits hydraulic pressure to the brake caliper in response to the amount of operation of a brake lever or a brake pedal, an electric motor that generates hydraulic pressure in the cylinder, and an electronic control unit that controls the electric motor based on a command signal sent from the driving assistance control device 8 and generates a braking force in response to the command.

[0044] The BSI indicator 7 is for supporting the rider in recognizing the presence of other vehicles around the rider by displaying a warning image of another vehicle present on the left rear side or right rear side, which is a blind spot from the rider while driving, on a display screen provided at a position visible to the rider. Note that the following describes a case where the BSI indicator 7 displays a warning image on the left side mirror 9L and the right side mirror 9R, which are easily visible to the rider while driving, but the present invention is not limited to this. For example, the BSI indicator 7 may display a warning image on the shield of a helmet worn by the rider in a manner visible to the rider while driving.

[0045] Fig. 2A is a diagram showing an example of a warning image 91 displayed when the following vehicle V1 reflected on the mirror surface of the right side mirror 9R is the target to be notified. Fig. 2A shows a case in which the BSI indicator 7 constantly lights up a triangular image at a predetermined brightness near the target to be notified reflected on the mirror surface of the right side mirror 9R as the warning image 91 for making the rider recognize the presence of the following vehicle V1 as the target to be notified reflected on the mirror surface of the right side mirror 9R, but the shape of the warning image 91 is not limited to this. The shape of the warning image 91 may be any shape as long as it can indicate to the rider the presence of the target to be notified.

[0046] Fig. 2B is a schematic diagram showing a case where the warning image 91 shown in Fig. 2A is blinked. The BSI indicator 7 more strongly suggests to the rider the presence of a target to be notified by blinking the constantly lit warning image 91. In other words, the BSI indicator 7 increases the intensity of the notification by blinking the constantly lit warning image 91.

[0047] Returning to Fig. 1, the driving assistance control device 8 is a computer responsible for control related to the driving assistance function. The driving assistance control device 8 includes a surrounding information acquisition unit 81, a driving position identification unit 83, a risk index calculation unit 84, a notification target recognition unit 85, a notification control unit 86, a course change prediction unit 87, and a driving position learning unit 88 as modules for realizing the BSI function among the multiple driving assistance functions.

[0048] The surrounding information acquisition unit 81 acquires surrounding information on the state of the surroundings of the vehicle, more specifically, information on the position, shape, type, and speed of the road and objects in front of the vehicle, the contents of road signs, and information on objects behind the vehicle, by performing sensor fusion processing on the detection results by the external sensor unit 2. The surrounding information acquisition unit 81 transmits the acquired surrounding information to, for example, the driving position identification unit 83, the risk index calculation unit 84, the notification target recognition unit 85, the course change prediction unit 87, and the driving position learning unit 88.

[0049] The driving position identification unit 83 identifies a position along the road width direction on the road on which the vehicle is traveling, based on the surrounding information transmitted from the surrounding information acquisition unit 81. More specifically, the driving position identification unit 83 identifies a road range on which the vehicle can travel as a driving range, based on the surrounding information acquired by the surrounding information acquisition unit 81, and identifies a driving position along the width direction of the vehicle within this driving range. The driving position identification unit 83 transmits the identified driving position information to the risk index calculation unit 84, the notification target recognition unit 85, the course change prediction unit 87, the driving position learning unit 88, etc.

[0050] FIG. 3 is a diagram showing an example of a driving range R0 specified by the driving position specifying unit 83. FIG. 3 shows an example of a road 200 with two lanes in each direction in an area where driving on the left side is specified. In the example shown in FIG. 3, the area between the center reservation strip L0 and the first division line L1 is set as a first lane 201, and the area between the first division line L1 and the second division line L2 is set as a second lane 202. In the example shown in FIG. 3, the vehicle V can physically travel between the second division line L2 and the curb 205 in addition to the two lanes 201, 202 defined between the center reservation strip L0 and the second division line L2. Therefore, the driving position specifying unit 83 specifies the road range between the center reservation strip 201 and the curb 205 as the driving range R0. The driving position identification unit 83 also divides the identified driving range R0 into a shoulder area R1 within a predetermined shoulder width between a widthwise end of the driving range R0 (the curb 205 in the example of FIG. 3) and the second dividing line L2, and a normal driving area R2 adjacent to the shoulder area R1. FIG. 3 shows a case where the host vehicle V, which is a motorcycle, is driving in the shoulder area R1.

[0051] Returning to FIG. 1, the risk index calculation unit 84 calculates a risk index for each vehicle present around the host vehicle, which becomes smaller as the risk of the host vehicle contacting each vehicle increases, based on the vehicle speed of the host vehicle acquired by the vehicle speed sensor 3 and the surrounding information acquired by the surrounding information acquisition unit 81. Note that in this embodiment, the risk index calculation unit 84 uses a so-called TTC (Time to Collision) obtained by dividing the inter-vehicle distance between the host vehicle and the target vehicle by the relative speed of the host vehicle with respect to the target vehicle as the risk index, but the present invention is not limited to this. The risk index calculation unit 84 transmits information on the calculated risk index for each surrounding vehicle to the course change prediction unit 87.

[0052] The notification target recognition unit 85 defines virtual notification areas on both the left and right rear sides of the vehicle, which are blind spots for the rider, and recognizes another vehicle that exists in at least one of the left and right notification areas and satisfies a predetermined notification condition (for example, a risk index for another vehicle existing in the notification area is equal to or less than a predetermined threshold) as a notification target. When the notification target recognition unit 85 recognizes another vehicle in the notification area as a notification target, the notification control unit 86 executes a first notification control or a second notification control according to a procedure described later, thereby making the rider aware of the presence of the notification target.

[0053] Here, a procedure for partitioning a virtual notification area in the notification target recognition unit 85 will be described with reference to Figures 4A to 4C (an example of two lanes on one side) and Figures 5A to 5C (an example of three lanes on one side). As described below, the notification target recognition unit 85 changes the length along the width direction of the notification area depending on the driving position.

[0054] Figure 4A is a schematic diagram showing the configuration of the right side notification area AR0 and the left side notification area AL0 virtually defined by the notification target recognition unit 85 of the host vehicle V traveling near the center of the second lane 202 of a two-lane road 200.

[0055] As shown in FIG. 4A, when the vehicle V is traveling near the center of the second lane 202, the notification target recognition unit 85 defines a rectangular right notification area AR0 on the right side rear as viewed from the rider of the vehicle V, and defines a rectangular left notification area AL0 on the left side rear. In this embodiment, the notification areas AR0 and AL0 are described as having the same length along the vehicle width direction and the same length along the traveling direction, but the present invention is not limited to this. The length of each side of the notification areas AR0 and AL0 may be different between the left and right sides depending on the traffic conditions in the target area. In the following, when the vehicle V is traveling near the center of the lanes 201 and 202 as shown in FIG. 4A, the lengths along the vehicle width direction of both notification areas AR0 and AL0 defined by the notification target recognition unit 85 are set to WR0 and WL0. In the following, when the vehicle V is traveling near the center of each lane 201, 202, the lengths WR0, WL0 along the vehicle width direction of both notification areas AR0, AL0 partitioned by the notification object recognition unit 85 are also referred to as basic lengths.

[0056] In the example shown in FIG. 4A, the following vehicle V1 is traveling within the right notification area AR0 and therefore may be a target for notification, but the following vehicle V2 is traveling outside both notification areas AR0 and AL0 and therefore may not be a target for notification.

[0057] Furthermore, when the vehicle V is traveling near the center of the first lane 201, the right side notification area and the left side notification area defined and formed by the notification target recognition unit 85 are qualitatively the same as the example shown in Figure 4A, so illustrations and detailed descriptions are omitted.

[0058] Fig. 4B is a schematic diagram showing the configuration of a right side notification area AR1 and a left side notification area AL0 virtually defined by the notification target recognition unit 85 of the host vehicle V traveling near the lane edge closer to the second dividing line L2 in the second lane 202 of the same two-lane road 200 as in Fig. 4A. That is, the example shown in Fig. 4B is different from the example shown in Fig. 4A in the traveling position of the host vehicle V in the second lane 202.

[0059] As shown in Fig. 4B, the notification target recognition unit 85, like the example shown in Fig. 4A, defines and forms a rectangular right notification area AR1 on the right hand side rear of the vehicle V as seen from the rider, and defines and forms a rectangular left notification area AL0 on the left hand side rear. As shown in Fig. 4B, when the vehicle V is traveling near the lane edge on the left hand side of the second lane 202 as seen from the rider, it is considered that the intention to move to the first lane 201 side on the right hand side as seen from the rider is weaker than the case shown in Fig. 4A. Therefore, the notification target recognition unit 85 makes the length WR1 along the vehicle width direction of the right notification area AR1 on the first lane 201 side, where the intention to move is considered to be weaker as seen from the rider, shorter than the basic length WR0 shown in Fig. 4A. More specifically, the notification target recognition unit 85 makes the length WR1 of the right-side notification area AR1 along the vehicle width direction shorter than the basic length WR0 so that the right edge line of the right-side notification area AR1 coincides with the first dividing line L1 that divides the first lane 201 and the second lane 202.

[0060] As a result, in the example shown in Figure 4B, the following vehicle V2 traveling in the same lane as the host vehicle V is traveling within the right-side notification area AR1 and therefore may be a target of notification, but the following vehicle V1 traveling in the first lane 201, where the rider of the host vehicle V is thought to have little intention of moving, is traveling outside both notification areas AR1 and AL0 and therefore cannot be a target of notification.

[0061] When the vehicle V travels in the road shoulder area R1 adjacent to the second lane 202, it is considered that the rider has little intention of crossing the second lane 202 and moving to the first lane 201 side, as in the example shown in Fig. 4B. Therefore, when the vehicle V travels in the road shoulder area R1, each notification area defined and formed by the notification target recognition unit 85 is qualitatively the same as in Fig. 4B, and therefore illustrations and detailed explanations are omitted.

[0062] Fig. 4C is a schematic diagram showing the configuration of a right side notification area AR0 and a left side notification area AL1 virtually defined by the notification target recognition unit 85 of the vehicle V traveling near the lane edge closer to the first dividing line L1 in the second lane 202 of the two-lane road 200 as in Figs. 4A and 4B. That is, the example shown in Fig. 4C is different from the examples shown in Figs. 4A and 4B in that the vehicle V is traveling in the second lane 202.

[0063] As shown in Fig. 4C, the notification target recognition unit 85, like the example shown in Fig. 4A, defines a rectangular right notification area AR0 on the right hand side rear of the vehicle V as seen from the rider, and defines a rectangular left notification area AL1 on the left hand side rear. As shown in Fig. 4C, when the vehicle V is traveling near the lane edge on the right hand side of the second lane 202 as seen from the rider, it is considered that the rider has little intention to move to the shoulder area R1 on the left hand side as seen from the rider, compared to the case shown in Fig. 4A. Therefore, the notification target recognition unit 85 makes the length WL1 along the vehicle width direction of the left notification area AL1 on the shoulder area R1 side where the rider has little intention to move from the rider shorter than the basic length WL0 shown in Fig. 4A. More specifically, the notification target recognition unit 85 shortens the length WL1 of the left side notification area AL1 along the vehicle width direction compared to the basic length WL0 so that the left edge line of the left side notification area AL1 coincides with the second dividing line L2 that divides the second lane 202 and the shoulder area R1.

[0064] As a result, in the example shown in Figure 4C, a following vehicle V2 traveling in the same lane as the host vehicle V and a following vehicle V1 traveling in the first lane 201 are both potential targets for notification because they are traveling within the left notification area AL1 and the right notification area AR1, respectively.

[0065] Figure 5A is a schematic diagram showing the configuration of the right side notification area AR0 and the left side notification area AL0 that are virtually defined by the notification target recognition unit 85 of the vehicle V traveling near the center of the second lane 302, which is the central lane, of a road 300 with three lanes on each side.

[0066] As shown in FIG. 5A, when the vehicle V is traveling near the center of the second lane 302, the notification target recognition unit 85 defines and forms the notification areas AR0, AL0 in the same range as the example shown in FIG. 4A.

[0067] In the example shown in Figure 5A, a following vehicle V1 traveling in the first lane 301 and a following vehicle V3 traveling in the third lane 303 are traveling within the notification areas AR0 and AL0, respectively, and therefore may be subject to notification, but a following vehicle V2 traveling in the same lane is traveling outside both notification areas AR0 and AL0 and therefore may not be subject to notification.

[0068] Furthermore, when the vehicle V is traveling near the center of the first lane 301 or near the center of the third lane 303, the right side notification area and the left side notification area defined and formed by the notification target recognition unit 85 are qualitatively the same as the example shown in Figure 5A, so illustrations and detailed explanations are omitted.

[0069] Fig. 5B is a schematic diagram showing the configuration of a right side notification area AR1 and a left side notification area AL0 virtually defined by the notification target recognition unit 85 of the host vehicle V traveling near the lane edge closer to the second dividing line L2 in the second lane 302 of the same three-lane road 300 as in Fig. 5A. That is, the example shown in Fig. 5B is different from the example shown in Fig. 5A in that the host vehicle V is traveling in the second lane 302.

[0070] As shown in Fig. 5B, the notification target recognition unit 85, like the example shown in Fig. 5A, defines and forms a rectangular right notification area AR1 on the right hand side rear of the vehicle V as seen from the rider, and defines and forms a rectangular left notification area AL0 on the left hand side rear. As shown in Fig. 5B, when the vehicle V is traveling near the lane edge on the left hand side of the second lane 302 as seen from the rider, it is considered that the intention to move to the first lane 301 side on the right hand side as seen from the rider is weaker than the case shown in Fig. 5A. Therefore, the notification target recognition unit 85 makes the length WR1 along the vehicle width direction of the right notification area AR1 on the first lane 301 side, where the intention to move is considered to be weaker as seen from the rider, shorter than the basic length WR0 shown in Fig. 5A. More specifically, the notification target recognition unit 85 makes the length WR1 of the right-side notification area AR1 along the vehicle width direction shorter than the basic length WR0 so that the right edge line of the right-side notification area AR1 coincides with the first dividing line L1 that divides the first lane 301 and the second lane 302.

[0071] As a result, in the example shown in Figure 5B, a following vehicle V2 traveling in the same lane as the host vehicle V and a following vehicle V3 traveling in the third lane 303 are capable of being notified because they are traveling within the respective notification areas AR1, AL0, but a following vehicle V1 traveling in the first lane 301, where the rider of the host vehicle V is thought to have little intention of moving, is not capable of being notified because it is traveling outside both notification areas AR1, AL0.

[0072] When the vehicle V travels near the lane edge closer to the third dividing line L3 of the third lane 303 or when the vehicle V travels in the road shoulder area R1 adjacent to the third lane 303, it is considered that the rider has little intention to move to the second lane 302 on the right hand side, as in the example shown in Fig. 5B. Therefore, when the vehicle V travels near the lane edge closer to the third dividing line L3 of the third lane 303 or when the vehicle V travels in the road shoulder area R1, each notification area defined and formed by the notification target recognition unit 85 is qualitatively the same as in Fig. 5B, and therefore illustration and detailed description are omitted.

[0073] Fig. 5C is a schematic diagram showing the configuration of a right side notification area AR0 and a left side notification area AL1 virtually defined by the notification target recognition unit 85 of the vehicle V traveling near the lane edge closer to the first dividing line L1 in the second lane 302 of the same three-lane road 300 as in Figs. 5A and 5B. That is, the example shown in Fig. 5C is different from the examples shown in Figs. 5A and 5B in that the vehicle V is traveling in the second lane 302.

[0074] As shown in Fig. 5C, the notification target recognition unit 85, like the example shown in Fig. 5A, defines a rectangular right notification area AR0 on the right hand side rear of the vehicle V as seen from the rider, and defines a rectangular left notification area AL1 on the left hand side rear. As shown in Fig. 5C, when the vehicle V is traveling near the lane edge on the right hand side of the second lane 302 as seen from the rider, it is considered that the intention to move to the third lane 303 on the left hand side as seen from the rider is weaker than the case shown in Fig. 5A. Therefore, the notification target recognition unit 85 makes the length WL1 along the vehicle width direction of the left notification area AL1 on the third lane 303 side, where the intention to move is considered to be weaker as seen from the rider, shorter than the basic length WL0 shown in Fig. 5A. More specifically, the notification target recognition unit 85 makes the length WL1 of the left side notification area AL1 along the vehicle width direction shorter than the basic length WL0 so that the left edge line of the left side notification area AL1 coincides with the second dividing line L2 that divides the second lane 302 and the third lane 303.

[0075] As a result, in the example shown in Figure 5C, a following vehicle V2 traveling in the same lane as the host vehicle V and a following vehicle V1 traveling in the first lane 301 are capable of being notified because they are traveling within the respective notification areas AR0, AL1, but a following vehicle V3 traveling in the third lane 303, where the rider of the host vehicle V is unlikely to have any intention of moving, is not capable of being notified because it is traveling outside both notification areas AR0, AL1.

[0076] When the host vehicle V travels near the lane edge closer to the second dividing line L2 of the third lane 303, similar to the example shown in Fig. 5C, it is considered that the rider has little intention of moving to the side of the road shoulder area R1 adjacent to the third lane 303. For this reason, when the host vehicle V travels near the lane edge closer to the second dividing line L2 of the third lane 303, the notification area defined and formed by the notification target recognition unit 85 is qualitatively the same as in Fig. 5C, and therefore illustration and detailed description are omitted.

[0077] As described above, when two or more lanes are defined in the normal driving area R2, the notification target recognition unit 85 changes the length of the left and right notification areas along the vehicle width direction according to the driving position of the vehicle V. More specifically, when the driving position is in the shoulder area R1, the notification target recognition unit 85 shortens the length along the vehicle width direction of the notification area on the normal driving area R2 side compared to when the driving position is near the center of each lane. In addition, when the driving position is near the lane edge of each lane (i.e., near the dividing line dividing each lane), the notification target recognition unit 85 shortens the length along the vehicle width direction of the notification area on the side where the dividing line is farther away compared to when the driving position is near the center of each lane.

[0078] 1, when a notification target is recognized by the notification target recognition unit 85, the notification control unit 86 executes notification control to notify the rider of the presence of the notification target by, for example, operating the BSI indicator 7 or the brake device 5. Here, the notification control unit 86 can execute two types of notification control to notify the rider of the presence of the notification target: a first notification control, and a second notification control in which the notification intensity for the rider is set higher than that of the first notification control in order to make the rider more aware of the presence of the notification target than that of the first notification control.

[0079] In this embodiment, the notification control unit 86 performs the first notification control by constantly lighting the warning image 91 (see FIG. 2A) to indicate the presence of an object to be notified by the BSI indicator 7, and performs the second notification control by flashing the warning image 91 (see FIG. 2B) to strongly indicate the presence of an object to be notified by the BSI indicator 7, but the present invention is not limited to this. In addition to flashing the warning image 91, the notification control unit 86 may perform the second notification control by causing the BSI indicator 7 to sound a warning sound, causing the brake device 5 to generate a brake pulse, or causing a vibration device (not shown) to vibrate the seat on which the rider sits.

[0080] When a new notification target is first recognized by the notification target recognition unit 85, the notification control unit 86 executes a first notification control with a relatively low notification intensity, and notifies the rider of the presence of the notification target. The notification control unit 86 continues to execute the first notification control while the notification target is being recognized by the notification target recognition unit 85. Thereafter, when a course change prediction unit 87 described later predicts a course change along the vehicle width direction of the vehicle while the first notification control is being performed (see Figs. 6A to 6F described later), the notification control unit 86 executes a second notification control with a higher notification intensity than the first notification control in order to avoid contact between the vehicle attempting to change course and the notification target present in the blind spot, and strongly notifies the rider of the presence of the notification target. In addition, when the rider operates the turn signal switch 4L, 4R on the side where the notification target is located while the first notification control is being performed, the notification control unit 86 executes the second notification control to strongly notify the rider of the presence of the notification target in order to avoid contact between the vehicle attempting to change lanes and the notification target located in the blind spot (see step ST10 in Figure 7B described below).

[0081] Based on the surrounding information transmitted from the surrounding information acquisition unit 81 and the traveling position information transmitted from the traveling position identification unit 83, the course change prediction unit 87 predicts the execution of a course change by the host vehicle along the vehicle width direction while at least one notification target is recognized by the notification target recognition unit 85, and transmits the prediction result to the notification control unit 86. More specifically, when the course change prediction unit 87 recognizes the presence of a movement causing factor that causes a course change along the width direction of the host vehicle ahead of the host vehicle based on the surrounding information, the course change prediction unit 87 predicts the execution of a course change by the host vehicle. In addition, when the course change prediction unit 87 predicts the execution of a course change, the notification control unit 86 executes the second notification control with a relatively high notification intensity as described above in order to strongly suggest the presence of the notification target to the rider as described above. Below, a specific example of a movement causing factor that causes the host vehicle to change course will be described with reference to FIG. 6A to FIG. 6F.

[0082] Fig. 6A is a diagram showing a first example of a movement triggering factor. Fig. 6A shows a case where a host vehicle V is traveling in a road shoulder area R1 on a one-lane road 100, and a following vehicle V1 is traveling in a right notification area behind the host vehicle V on the right side. In the example of Fig. 6A, the notification target recognition unit 85 of the host vehicle V recognizes the following vehicle V1 as a notification target, and the notification control unit 86 executes a first notification control to notify the presence of the notification target.

[0083] In the situation shown in Fig. 6A, an obstacle O1 located ahead of the host vehicle V in the traveling direction and on the road shoulder area R1 becomes a movement causing factor that causes the host vehicle V traveling on the road shoulder area R1 to change course toward the normal driving area R2. Also, in the situation shown in Fig. 6A, if the host vehicle V changes course toward the normal driving area R2 to avoid contact with the obstacle O1, there is a risk of contact between the host vehicle V and the following vehicle V1.

[0084] Therefore, when the lane change prediction unit 87 recognizes that the vehicle V is traveling in the shoulder area R1 and that an obstacle O1 exists ahead of the vehicle V in the traveling direction as a movement inducing factor while at least one notification object is being recognized, the lane change prediction unit 87 predicts that the vehicle V will change course from the shoulder area R1 to the normal traveling area R2. In response to the lane change prediction unit 87 predicting the execution of the lane change while the first notification control for the following vehicle V1 is being executed, the notification control unit 86 executes the second notification control with a higher notification intensity, and can make the rider of the vehicle V strongly aware of the presence of the following vehicle V1 before starting the lane change, thereby making it possible to avoid contact between the vehicle V and the following vehicle V1.

[0085] Fig. 6B is a diagram showing a second example of a movement triggering factor. Fig. 6B shows a case where, on a one-lane road 100, the host vehicle V is traveling in a normal driving area R2, a following vehicle V1 is traveling in a left notification area behind the host vehicle V on the left side, and a leading vehicle V5 is traveling ahead of the host vehicle V in the traveling direction. In the example of Fig. 6B, the notification target recognition unit 85 of the host vehicle V recognizes the following vehicle V1 as a notification target, and the notification control unit 86 is executing the first notification control to notify the presence of the notification target.

[0086] In the situation shown in Fig. 6B, when the rider of the host vehicle V is in a hurry, that is, when the risk index for the leading vehicle V5 is equal to or lower than a predetermined threshold, the leading vehicle V5 becomes a movement inducing factor that causes the host vehicle V traveling in the normal driving area R2 to change course toward the shoulder area R1. Also, in the situation shown in Fig. 6B, if the host vehicle V changes course toward the shoulder area R1 to avoid contact with the leading vehicle V5, there is a risk of contact between the host vehicle V and the following vehicle V1.

[0087] Therefore, while at least one notification target is being recognized, if the driving position of the host vehicle V is in the normal driving area R2, a leading vehicle V5 exists ahead of the host vehicle V in the traveling direction as a movement inducing factor, and the risk index for the leading vehicle V5 calculated by the risk index calculation unit 84 is equal to or less than a predetermined threshold, the lane change prediction unit 87 predicts that the host vehicle V will change course from the normal driving area R2 to the road shoulder area R1. In response to the prediction of the execution of the lane change by the lane change prediction unit 87 while the first notification control for the following vehicle V1 is being executed, the notification control unit 86 executes the second notification control with a higher notification intensity, and can make the rider of the host vehicle V strongly aware of the presence of the following vehicle V1 before starting the lane change, thereby making it possible to avoid contact between the host vehicle V and the following vehicle V1.

[0088] Fig. 6C is a diagram showing a third example of a movement triggering factor. Fig. 6C shows a case where the host vehicle V is traveling on the second lane 202 in the normal driving area R2 on a two-lane road 200, a following vehicle V1 is traveling in the right notification area on the right rear of the host vehicle V, and a leading vehicle V5 is traveling ahead of the host vehicle V in the traveling direction. In the example of Fig. 6C, the notification target recognition unit 85 of the host vehicle V recognizes the following vehicle V1 as a notification target, and the notification control unit 86 executes the first notification control to notify the presence of the notification target.

[0089] In the situation shown in Fig. 6C, when the rider of the host vehicle V is in a hurry, that is, when the risk index for the leading vehicle V5 is equal to or less than a predetermined threshold, the leading vehicle V5 becomes a movement inducing factor that causes the host vehicle V traveling in the second lane 202 to change course toward the first lane 201. Also, in the situation shown in Fig. 6C, if the host vehicle V changes course toward the first lane 201 to avoid contact with the leading vehicle V5, there is a risk of contact between the host vehicle V and the following vehicle V1.

[0090] Therefore, when at least one notification object is recognized and the host vehicle V is traveling on a road with two or more lanes, if the host vehicle V is traveling in the normal traveling area R2, there is a preceding vehicle V5 as a movement causing factor ahead of the host vehicle V in the traveling direction, and the risk index for the preceding vehicle V5 calculated by the risk index calculation unit 84 is equal to or less than a predetermined threshold, the lane change prediction unit 87 predicts that the host vehicle V will change its course to an adjacent lane (the first lane 201 in the example of FIG. 6C). In response to the prediction of the execution of the course change by the course change prediction unit 87 while the first notification control for the following vehicle V1 is being executed, the notification control unit 86 executes the second notification control with a higher notification intensity, and can make the rider of the host vehicle V strongly aware of the presence of the following vehicle V1 before starting the course change, thereby making it possible to avoid contact between the host vehicle V and the following vehicle V1.

[0091] Fig. 6D is a diagram showing a fourth example of a movement triggering factor. Fig. 6D shows a case where, on a one-lane road 100, the host vehicle V is traveling in a normal driving area R2, the following vehicle V1 is traveling in a left notification area behind the host vehicle V on the left side, the leading vehicle V5 is traveling ahead of the host vehicle V in the traveling direction, and a traffic light S is present ahead of the leading vehicle V5. The example of Fig. B shows a case where the display mode of the traffic light S means no entry or stop. The example of Fig. 6D shows a case where the notification target recognition unit 85 of the host vehicle V recognizes the following vehicle V1 as a notification target, and the notification control unit 86 is executing the first notification control to notify the presence of the notification target.

[0092] In the situation shown in Fig. 6D, the preceding vehicle V5 and traffic light S present ahead of the host vehicle V in the traveling direction become movement-inducing factors that cause the host vehicle V traveling in the normal traveling area R2 to change course toward the shoulder area R1 if the display mode of the traffic light S indicates no entry or stop. Also, in the situation shown in Fig. 6D, if the host vehicle V changes course toward the shoulder area R1 to avoid contact with the preceding vehicle V5, there is a risk of contact between the host vehicle V and the following vehicle V1.

[0093] Therefore, while at least one notification object is being recognized, if the vehicle V is traveling within the normal traveling area R2, a preceding vehicle V5 and a traffic light S are present ahead of the vehicle V in the traveling direction as movement inducing factors, and the display mode of the traffic light S indicates no entry or stop, the lane change prediction unit 87 predicts that the vehicle V will change course from the normal traveling area R2 to the road shoulder area R1. In response to the prediction of the execution of the lane change by the lane change prediction unit 87 while the first notification control for the following vehicle V1 is being executed, the notification control unit 86 executes the second notification control with a higher notification intensity, and can make the rider of the vehicle V strongly aware of the presence of the following vehicle V1 before starting the lane change, thereby making it possible to avoid contact between the vehicle V and the following vehicle V1.

[0094] Fig. 6E is a diagram showing a fifth example of a movement triggering factor. Fig. 6E shows a case where, on a one-lane road 100, the host vehicle V is traveling in a normal driving area R2, a following vehicle V1 is traveling in a left notification area behind the host vehicle V on the left side, and a leading vehicle V5 is traveling ahead of the host vehicle V in the traveling direction. Also, in the example of Fig. 6E, the notification target recognition unit 85 of the host vehicle V recognizes the following vehicle V1 as a notification target, and the notification control unit 86 is executing the first notification control to notify the presence of the notification target.

[0095] In the situation shown in Fig. 6E, when the direction indicator or brake lamp of the leading vehicle V5 in front of the host vehicle V is on, it becomes a movement inducing factor that causes the host vehicle V traveling in the normal driving area R2 to change course toward the shoulder area R1. Also, in the situation shown in Fig. 6E, if the host vehicle V changes course toward the shoulder area R1 to avoid contact with the leading vehicle V5, there is a risk of contact between the host vehicle V and the following vehicle V1.

[0096] Therefore, while at least one notification object is being recognized, if the driving position of the host vehicle V is within the normal driving area R2, a leading vehicle V5 exists ahead of the host vehicle V in the traveling direction as a movement inducing factor, and further the direction indicator or brake lamp of the leading vehicle V5 is turned on, the lane change prediction unit 87 predicts that the host vehicle V will change course from the normal driving area R2 to the road shoulder area R1. In response to the prediction of the execution of the lane change by the lane change prediction unit 87 while the first notification control for the following vehicle V1 is being executed, the notification control unit 86 executes the second notification control with a higher notification intensity, and can make the rider of the host vehicle V strongly aware of the presence of the following vehicle V1 before starting the lane change, thereby making it possible to avoid contact between the host vehicle V and the following vehicle V1.

[0097] Fig. 6F is a diagram showing a sixth example of a movement triggering factor. Fig. 6F shows a case where, on a two-lane road 200, the host vehicle V is traveling in the second lane 202 in the normal driving area R2, a following vehicle V1 is traveling in the right notification area on the right rear of the host vehicle V, and a leading vehicle V5 is traveling ahead of the host vehicle V in the traveling direction. In the example of Fig. 6F, the notification target recognition unit 85 of the host vehicle V recognizes the following vehicle V1 as a notification target, and the notification control unit 86 is executing the first notification control to notify the presence of the notification target.

[0098] In the situation shown in Fig. 6F, when the leading vehicle V5 present ahead of the host vehicle V in the traveling direction has its turn signal or brake lamps on, it becomes a movement-inducing factor that causes the host vehicle V traveling in the second lane 202 to change course toward the first lane 201. Also, in the situation shown in Fig. 6F, if the host vehicle V changes course toward the first lane 201 to avoid contact with the leading vehicle V5, there is a risk of contact between the host vehicle V and the following vehicle V1.

[0099] Therefore, when at least one notification object is recognized and the host vehicle V is traveling on a road with two or more lanes, the host vehicle V is traveling within the normal traveling area R2, a preceding vehicle V5 exists ahead of the host vehicle V in the traveling direction as a movement inducing factor, and the preceding vehicle V5 has its turn signal or brake lamp turned on, the lane change prediction unit 87 predicts that the host vehicle V will change its course to an adjacent lane (the first lane 201 in the example of FIG. 6F). In response to the prediction of the execution of the course change by the course change prediction unit 87 while the first notification control for the following vehicle V1 is being executed, the notification control unit 86 executes the second notification control with a higher notification intensity, and can make the rider of the host vehicle V strongly aware of the presence of the following vehicle V1 before starting the course change, thereby making it possible to avoid contact between the host vehicle V and the following vehicle V1.

[0100] Here, as shown in Figures 6B, 6D, and 6E, an exception will be described when predicting that the vehicle V will change course from the normal driving area R2 to the shoulder area R1. For example, when the vehicle V continues to travel on the edge of the normal driving area R2 for a predetermined time or more, it is considered that the rider of the vehicle V is intentionally traveling on the edge of the normal driving area R2 for traffic safety. For this reason, when the vehicle V is in the normal driving area R2 and travels within a predetermined distance a (see Figure 6B) from the dividing line L1 that divides the shoulder area R1 and the normal driving area R2 for a predetermined time or more, it is preferable that the course change prediction unit 87 predicts that the vehicle V will not change course from the normal driving area R2 to the shoulder area R1 even when the movement causing factor as shown in Figures 6B, 6D, and 6E is recognized.

[0101] Returning to Fig. 1, the case has been described in which the course change prediction unit 87 predicts the execution of a course change by the vehicle based on the surrounding information transmitted from the surrounding information acquisition unit 81, the risk index calculated by the risk index calculation unit 84, and the like, but the present invention is not limited to this. The course change prediction unit 87 may predict the execution of a course change by the vehicle based on the learning result of the traveling position of the vehicle in the road width direction by the traveling position learning unit 88 described later, in addition to the surrounding information and the risk index. In this way, the course change prediction unit 87 can predict the execution of a course change by the vehicle taking into account the driving tendency of the rider of the vehicle, thereby improving the prediction accuracy.

[0102] The traveling position learning unit 88 learns the traveling position of the host vehicle in the road width direction based on the surrounding information transmitted from the surrounding information acquisition unit 81 and the traveling position information transmitted from the traveling position identification unit 83. More specifically, the traveling position learning unit 88 learns the traveling position of the host vehicle for each of various traffic scenes classified according to the road configuration, surrounding traffic conditions, etc. The traveling position learning unit 88 transmits information related to the learning result of the traveling position of the host vehicle to the course change prediction unit 87.

[0103] 7A and 7B are flowcharts showing specific steps of a notification process for notifying a rider of the vehicle of the presence of another vehicle approaching from the rear side. The process shown in Fig. 7A and 7B is executed by the driving assistance control device 8 at a predetermined cycle while the vehicle is traveling.

[0104] First, in step ST1, the surrounding information acquisition unit 81 acquires surrounding information on the state of the surroundings of the vehicle based on the detection result by the external sensor unit 2, and proceeds to step ST2. In step ST2, the traveling position identification unit 83 identifies the traveling position of the vehicle on the road on which the vehicle is traveling based on the surrounding information, and proceeds to step ST3.

[0105] In step ST3, the notification target recognition unit 85 divides the left and right notification areas into ranges corresponding to the vehicle's traveling position based on the surrounding information and the vehicle's traveling position, in accordance with the procedures described with reference to Figures 4A to 4C and Figures 5A to 5C, and then proceeds to step ST4.

[0106] In step ST4, the notification target recognition unit 85 determines whether or not another vehicle is present in the left and right notification areas defined in step ST3 based on the surrounding information. If the result of the determination in step ST4 is NO, the notification target recognition unit 85 ends the notification process, and if the result is YES, the notification target recognition unit 85 proceeds to step ST5.

[0107] In step ST5, the risk index calculation unit 84 calculates a risk index for the other vehicle determined to be in the notification area in step ST4, and proceeds to step ST6. In step ST6, the notification target recognition unit 85 determines whether the risk index for the other vehicle calculated in step ST5 is equal to or smaller than a predetermined threshold. If the determination result in step ST6 is NO, the notification target recognition unit 85 ends the notification process, and if the determination result is YES, proceeds to step ST7.

[0108] In step ST7, the notification target recognition unit 85 recognizes another vehicle that exists in the notification area and has a risk index equal to or less than a threshold as a notification target, and proceeds to step ST8. In step ST8, the notification control unit 86 executes a first notification control to notify the rider of the host vehicle of the presence of the notification target recognized in step ST7, and proceeds to step ST10.

[0109] In step ST10, the notification control unit 86 determines whether or not the turn signal switch on the side where the notification target exists has been operated by the rider of the vehicle. If the determination result in step ST10 is NO, the notification control unit 86 proceeds to step ST11.

[0110] If the determination result in step ST10 is YES, the notification control unit 86 determines that there is a risk of contact between the vehicle attempting to change direction and the notification target approaching from behind, and proceeds to step ST20. In step ST20, the notification control unit 86 executes the second notification control and ends the notification process.

[0111] In step ST11, the course change prediction unit 87 judges whether or not the vehicle is traveling in a road shoulder area and whether or not an obstacle exists ahead of the vehicle in the traveling direction as a movement causing factor, as described with reference to Fig. 6A. If the judgment result in step ST11 is YES, the course change prediction unit 87 judges that the vehicle will change its course from the road shoulder area to a normal traveling area, and proceeds to step ST20. If the judgment result in step ST11 is NO, the course change prediction unit 87 proceeds to step ST12.

[0112] In step ST12, as described with reference to Fig. 6D, the lane change prediction unit 87 judges whether the vehicle is in the normal driving area, whether there are other vehicles and traffic lights ahead of the vehicle as movement causing factors, and whether the display mode of the traffic lights indicates no entry or stop. If the judgment result of step ST12 is YES, the lane change prediction unit 87 judges that the vehicle will change course from the normal driving area to the shoulder area, and proceeds to step ST20. If the judgment result of step ST12 is NO, the lane change prediction unit 87 proceeds to step ST13.

[0113] In step ST13, as described with reference to Fig. 6E and Fig. 6F, the course change prediction unit 87 judges whether the driving position of the host vehicle is within the normal driving area, whether there is another vehicle ahead of the host vehicle in the traveling direction as a movement causing factor, and whether the turn signal or brake lamp of the other vehicle ahead is on. If the judgment result of step ST13 is YES, the course change prediction unit 87 judges that the host vehicle will change course from the normal driving area to the road shoulder area, and proceeds to step ST20. If the judgment result of step ST13 is NO, the course change prediction unit 87 proceeds to step ST14.

[0114] In step ST14, as described with reference to Fig. 6B and Fig. 6C, the course change prediction unit 87 judges whether or not the vehicle is in the normal driving area, there is another vehicle ahead of the vehicle in the traveling direction as a movement causing factor, and the risk index for the other vehicle is equal to or less than a predetermined threshold. If the judgment result in step ST14 is YES, the course change prediction unit 87 judges that the vehicle will change course from the normal driving area to the road shoulder area, and proceeds to step ST20. If the judgment result in step ST14 is NO, the course change prediction unit 87 ends the notification process.

[0115] The driving assistance system 1 according to this embodiment has the following advantages. (1) In the driving assistance system 1, the surrounding information acquisition unit 81 acquires surrounding information on the state of the surroundings of the vehicle, the notification target recognition unit 85 recognizes other vehicles existing in a notification area defined on the rear side of the vehicle as a notification target, and the notification control unit 86 performs a first notification control to notify the occupant of the vehicle of the presence of the notification target. The course change prediction unit 87 predicts the execution of a course change by the vehicle while the notification target is recognized based on the surrounding information. Here, if the vehicle is capable of traveling on the shoulder of the road, such as a motorcycle, the occupant of the vehicle may enter or exit the shoulder of the road without activating the turn indicators 6L and 6R as described above. In response to this, in the driving assistance system 1, the notification control unit 86 performs a second notification control with a higher notification intensity than the first notification control when a course change is predicted based on the surrounding information while the first notification control is being performed, i.e., while the presence of the notification target is being recognized. As a result, according to the driving assistance system 1, if an occupant of the vehicle attempts to change course without recognizing the presence of the object to be notified and without activating the turn indicators 6L, 6R, the notification control unit 86 performs a second notification control with high notification intensity, so that the occupant of the vehicle can recognize the presence of the object to be notified before actually changing the course of the vehicle body, thereby improving traffic safety.

[0116] (2) When the lane change prediction unit 87 recognizes the presence of a movement inducing factor that causes the vehicle to move along the width direction of the vehicle based on the surrounding information, the lane change prediction unit 87 predicts that the vehicle will change lane. Therefore, according to the driving assistance system 1, the second notification control can be performed before the vehicle body of the vehicle actually starts a lane change operation, so that the rider can have enough time to check the surrounding situation and determine whether or not to change lane.

[0117] (3) When the lane change prediction unit 87 recognizes that the vehicle is currently in the road shoulder area R1 and that an obstacle O1 exists ahead of the vehicle in the traveling direction, the lane change prediction unit 87 predicts that the vehicle will change course from the road shoulder area R1 to the normal traveling area R2. Therefore, the driving assistance system 1 can perform the second notification control before the vehicle body actually starts a lane change operation to avoid contact with the obstacle O1 ahead, so that the occupant can have enough time to check the surrounding situation and determine whether or not to change course.

[0118] (4) When the vehicle is in the normal driving region R2, a vehicle ahead of the vehicle is present as a movement-causing factor, and the risk index for the vehicle ahead is equal to or lower than a predetermined threshold, the lane change prediction unit 87 predicts that the vehicle will change its lane to avoid contact with the vehicle ahead. Therefore, the driving support system 1 can perform the second notification control before the vehicle body of the vehicle actually starts a lane change operation to avoid contact with the vehicle ahead, so that the occupant can have enough time to check the surrounding situation and determine whether or not to change lane.

[0119] (5) The lane change prediction unit 87 predicts that the host vehicle will change lane when the host vehicle is in the normal driving area R2, there is a preceding vehicle and a traffic light S ahead of the host vehicle in the traveling direction as movement inducing factors, and the display mode of the traffic light S indicates no entry or stop. Therefore, according to the driving assistance system 1, the second notification control can be performed before the host vehicle actually starts a lane change operation to avoid contact with the preceding vehicle that is trying to stop, so that the occupant can have enough time to check the surrounding situation and determine whether or not to change lane.

[0120] (6) The lane change prediction unit 87 predicts that the host vehicle will change lane when the host vehicle is in the normal driving area R2, there is a vehicle ahead of the host vehicle in the traveling direction as a movement trigger, and the brake lights of the vehicle ahead are on. Therefore, according to the driving assistance system 1, the second notification control can be performed before the host vehicle actually starts changing lane to avoid contact with the vehicle ahead that is trying to stop, so that the occupant can have enough time to check the surrounding situation and determine whether or not to change lane.

[0121] (7) When the vehicle is in the normal driving region R2, there is a vehicle ahead of the vehicle in the traveling direction as a movement trigger, and the vehicle ahead has its turn signal on, the lane change prediction unit 87 predicts that the vehicle will change lane. Therefore, the driving assistance system 1 can perform the second notification control before the vehicle actually starts a lane change operation to avoid contact with the vehicle ahead that is trying to change lane, so that the occupant can have enough time to check the surrounding situation and determine whether or not to change lane.

[0122] (8) As shown in Figures 4A to 4C and 5A to 5C, when two or more lanes are defined in the normal driving area R2, the notification target recognition unit 85 changes the length along the width direction of the notification area according to the driving position of the vehicle. This prevents the rider from being annoyed by frequent notifications that are issued due to the recognition of other vehicles driving in lanes in which the rider has no intention of driving as notification targets.

[0123] (9) As shown in Figures 4A to 4C and 5A to 5C, when the driving position is in the shoulder area R1 or near the edge of each lane, the notification target recognition unit 85 shortens the length along the width direction of the notification area compared to when the driving position is in the center of each lane. This prevents the rider from being annoyed by frequent notifications that are issued due to the rider recognizing other vehicles traveling in lanes in which the rider has no intention of traveling as notification targets.

[0124] (10) When the host vehicle is in the normal driving area R2 and continues to travel within a predetermined distance a (see FIG. 6B) from the dividing line L1 that divides the shoulder area R1 and the normal driving area R2 for a predetermined time or more, the course change prediction unit 87 determines that the rider of the host vehicle has no intention of entering the shoulder area R1, and predicts that the host vehicle will not change course from the normal driving area R2 to the shoulder area R1. Therefore, according to the driving assistance system 1, it is possible to prevent the rider from feeling annoyed by the frequent second notification control being performed for the rider who has no intention of traveling in the shoulder area R1.

[0125] (11) The traveling position learning unit 88 learns the traveling position of the vehicle in the road width direction, and the course change prediction unit 87 predicts the execution of a course change based on the surrounding information and the learning result of the traveling position learning unit 88. Therefore, according to the driving assistance system 1, the execution of a course change can be predicted taking into account the tendency of the past traveling position, so that the timing of executing the second notification control can be made suitable for the rider.

[0126] (12) Saddle-type vehicles such as motorcycles and buggies are narrower and lighter than four-wheeled automobiles, and therefore may enter or exit the road shoulder without activating the turn signal. Therefore, according to the present invention, the first and second notification controls are performed for such saddle-type vehicles in the above-described procedure, thereby improving traffic safety.

[0127] Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment. The detailed configuration may be appropriately changed within the scope of the spirit of the present invention. [Explanation of symbols]

[0128] 1. Driving assistance systems 2...External sensor unit 3...Vehicle speed sensor 4L, 4R...Turn indicator switch 5. Brake device 6L,6R…Direction indicator 7…BSI indicator 8...Driver assistance control device 81...surrounding information acquisition unit (surrounding information acquisition means) 83...traveling position identification unit (traveling position identification means) 84...Risk index calculation unit (risk index calculation means) 85...notification target recognition unit (notification target recognition means) 86...Notification control unit (notification control means) 87... Course change prediction unit (course change prediction means) 88...traveling position learning unit (traveling position learning means) 9L, 9R…Side mirror

Claims

1. A surrounding information acquisition means for acquiring surrounding information relating to a surrounding state of the host vehicle; a notification target recognition means for recognizing another vehicle present within a notification area defined behind and to the side of the host vehicle as a notification target based on the surrounding information; A driving assistance system including: a notification control means for performing a first notification control to notify an occupant of the vehicle of the presence of the notification object when the notification object is recognized; A course change prediction means for predicting whether or not the vehicle will change course while the notification target is being recognized based on the surrounding information, A driving assistance system characterized in that, when the lane change prediction means predicts that the lane change will be executed while the first notification control is being performed, the notification control means performs a second notification control having a higher notification intensity than the first notification control.

2. The driving assistance system according to claim 1, characterized in that the lane change prediction means predicts the execution of the lane change when it recognizes, based on the surrounding information, the presence of a movement causing factor that causes movement along a width direction of the vehicle ahead in the traveling direction of the vehicle.

3. A road on which the vehicle is traveling is divided into a shoulder area within a predetermined width from a width direction end and a normal traveling area adjacent to the shoulder area, and a traveling position identification means is further provided for identifying a traveling position of the vehicle on the road, The driving assistance system according to claim 2, characterized in that when the lane change prediction means recognizes that the driving position is in the road shoulder area and that an obstacle as the movement causing factor is present ahead of the vehicle in the traveling direction, the lane change prediction means predicts that the vehicle will change course from the road shoulder area to the normal driving area.

4. a travel position identification means for dividing a road on which the vehicle is traveling into a shoulder area within a predetermined width from a width direction end and a normal travel area adjacent to the shoulder area, and for identifying a travel position of the vehicle on the road; and a risk index calculation means for calculating a risk index based on the surrounding information, the risk index decreasing as the risk of the host vehicle contacting the leading vehicle increases when a leading vehicle is present ahead in the traveling direction of the host vehicle, The driving assistance system according to claim 2, characterized in that the lane change prediction means predicts the execution of the lane change when the driving position is in the normal driving area, the preceding vehicle as the movement causing factor is present ahead of the vehicle in the direction of travel, and the risk index for the preceding vehicle is below a predetermined threshold value.

5. A road on which the vehicle is traveling is divided into a shoulder area within a predetermined width from a width direction end and a normal traveling area adjacent to the shoulder area, and a traveling position identification means is further provided for identifying a traveling position of the vehicle on the road, The driving assistance system according to claim 2, characterized in that the lane change prediction means predicts the execution of the lane change when the driving position is in the normal driving area, a preceding vehicle and a traffic light as the movement causing factor are present ahead of the vehicle in the direction of travel, and the display mode of the traffic light indicates a no entry or a stop.

6. A road on which the vehicle is traveling is divided into a shoulder area within a predetermined width from a width direction end and a normal traveling area adjacent to the shoulder area, and a traveling position identification means is further provided for identifying a traveling position of the vehicle on the road, The driving assistance system according to claim 2, characterized in that the lane change prediction means predicts the execution of the lane change when the driving position is in the normal driving area, a leading vehicle is present in front of the vehicle in the direction of travel as the movement causing factor, and the brake lights of the leading vehicle are illuminated.

7. A road on which the vehicle is traveling is divided into a shoulder area within a predetermined width from a width direction end and a normal traveling area adjacent to the shoulder area, and a traveling position identification means is further provided for identifying a traveling position of the vehicle on the road, The driving assistance system according to claim 2, characterized in that the lane change prediction means predicts the execution of the lane change when the driving position is in the normal driving area, a leading vehicle as the movement causing factor is present ahead in the direction of travel of the vehicle, and a turn signal is on in the leading vehicle.

8. A driving assistance system as described in any one of claims 3 to 7, characterized in that the notification object recognition means changes the length along the width direction of the notification area depending on the driving position when two or more lanes are defined in the normal driving area.

9. The driving assistance system of claim 8, characterized in that the notification object recognition means shortens the length along the width direction of the notification area when the driving position is in the shoulder area or the edge of each lane compared to when the driving position is in the center of each lane.

10. A road on which the vehicle is traveling is divided into a shoulder area within a predetermined width from a width direction end and a normal traveling area adjacent to the shoulder area, and a traveling position identification means is further provided for identifying a traveling position of the vehicle on the road, The driving assistance system according to claim 2, characterized in that the course change prediction means predicts that the vehicle will not change course from the normal driving area to the shoulder area when the vehicle is within the normal driving area and traveling within a predetermined distance from a line separating the shoulder area from the normal driving area for a predetermined period of time or more.

11. A traveling position learning means for learning a traveling position of the vehicle in a road width direction, 2. The driving support system according to claim 1, wherein the course change prediction means predicts the execution of the course change based on the surrounding information and a learning result of the traveling position learning means.

12. 2. The driving assistance system according to claim 1, wherein the host vehicle is a saddle-ride type vehicle.

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