DRIVING ASSISTANCE SYSTEM

Abstract

Problem to be solved: To provide suitable support for a driver's driving operation through a driver assistance system when the driving condition of a vehicle ahead is abnormal. Solution: A driver assistance system 10 comprises: environment detection devices 11 and 12 that detect the environment of a vehicle 1, including a vehicle 2 ahead that is in lane L1 in which the vehicle 1 is traveling; a determination unit 22 that is configured to determine, based on information about the vehicle 2 ahead detected by the environment detection devices 11 and 12, whether the driving condition of the vehicle 2 ahead is normal or not; and a notification control unit 23 that is configured to control a message device 50 to provide a notification prompting the driver to overtake the vehicle 2 ahead if the determination unit 22 determines that the driving condition of the vehicle 2 ahead is abnormal.

Description

[0001] The present invention relates to a driver assistance system that supports a driver's driving operations.

[0002] An adaptive cruise control (ACC) function of a vehicle is known to regulate the distance between vehicles in order to follow a vehicle ahead at an appropriate distance, thus assisting the driver. If the vehicle ahead accelerates or decelerates while the adaptive cruise control is in operation, the vehicle's acceleration or deceleration is automatically adjusted to maintain the appropriate distance at or below a set vehicle speed. Regarding the control of the adaptive cruise control with respect to a vehicle ahead, patent literature 1 discloses, for example, a device that detects dangerous behavior of a vehicle ahead and controls both the following function and the deactivation of this following function.The device described in patent literature 1 detects at least one of the following as dangerous behaviors of the vehicle ahead: exceeding a speed limit, sudden acceleration, sudden braking, a U-turn, failure to stay in the lane, excessively low vehicle speed, and excessive vehicle speed. As soon as the dangerous behavior of the vehicle ahead is detected, the device described in patent literature 1 deactivates the following function and prevents dangerous following.

[0003] [Patent Literature 1] JP 6289669 B2

[0004] If, in the device described in patent literature 1, the following function with respect to the vehicle ahead is deactivated, the driving operation is switched to manual control by the driver. In other words, if the following function is deactivated, the driver must perform a driving operation manually in a situation where the vehicle ahead is behaving dangerously. Switching to manual control in an abnormal driving situation, where the vehicle ahead is exhibiting dangerous behavior, places a significant burden on the driver. The desire has been expressed to provide suitable support for the driver's driving operation when the driving situation of the vehicle ahead is abnormal.

[0005] The present invention was conceived in view of the above circumstances, and one of its objectives is to assist the driving operation of a driver in a suitable manner when the driving condition of a vehicle ahead is abnormal.

[0006] According to one aspect of the present invention, a driver assistance system comprises: an environment detection device that detects the vehicle's environment, including a vehicle ahead that is in a lane in which the vehicle is traveling; a determination unit configured to determine, based on information regarding the vehicle ahead detected by the environment detection device, whether the driving condition of the vehicle ahead is normal or not; and a notification control unit configured to control a message device to provide a notification prompting the driver to overtake the vehicle ahead when the determination unit determines that the driving condition of the vehicle ahead is abnormal.

[0007] The driver assistance system according to the present invention is able to support the driving operation of a driver in a suitable manner when a driving condition of a vehicle driving ahead is abnormal. Fig. Figure 1 is a block diagram showing a schematic configuration of a driver assistance system in a first embodiment of the present invention. Fig. Figure 2 is a diagram showing a vehicle and a vehicle ahead of it, which is in a lane on which the vehicle is traveling. Fig. Figure 3 is a diagram showing the vehicle, the vehicle ahead, and another vehicle in an adjacent lane. Fig. Figure 4 is a diagram showing the vehicle, the vehicle ahead, and a vehicle in front of the vehicle ahead. Fig. Figure 5 is an example of a representation for determining the driving state of the vehicle ahead. Fig. Figure 6 is a flowchart to explain the notification control process in the first embodiment. Fig. Figure 7 is an example of an image for determining the driving state of a vehicle ahead in a second embodiment. Fig. Figure 8 is a flowchart to explain the notification control process in the second embodiment. Fig. Figure 9 is an example of an image for determining the driving state of a vehicle ahead in a third embodiment. First embodiment

[0008] In the following, a driver assistance system according to a first embodiment of the present invention is described in detail with reference to the drawings. Fig. Figure 1 is a block diagram showing a schematic configuration of a driver assistance system 10 in the present embodiment. The driver assistance system 10 in the present embodiment is configured to support driving operations of a driver in a vehicle (which can also be referred to as the host vehicle) with the driver assistance system 10 installed therein.

[0009] As in Fig. As shown in Figure 1, the driver assistance system 10 comprises an image capture device 11, an obstacle detection device 12, a vehicle speed sensor 13 which detects the vehicle speed, an operating input device 14, a vehicle-to-vehicle communication function 15, a control unit 20, a braking device 30, a drive device 40 and a signaling device 50.

[0010] The image acquisition device 11 is configured to image an area surrounding the vehicle. The image acquisition device 11 is configured as a digital camera with an image sensor such as a CCD or CMOS element and is configured to output information regarding the vehicle's surroundings as a still image and / or as a moving image. Image data of the surrounding area captured by the image acquisition device 11 is entered into the control unit 20.

[0011] The obstacle detection device 12 is configured to detect obstacles in the vicinity of the vehicle and to measure the relative distance (vehicle-to-obstacle distance) between the vehicle and each obstacle. A millimeter-wave radar, a sonar sensor, a LiDAR (Light Detection and Ranging) system, or similar device can be used as the obstacle detection device 12. The distance measurement by the obstacle detection device 12 is performed dynamically in predetermined measurement cycles. The distance between the vehicle and each obstacle detected by the obstacle detection device 12 is entered into the control unit 20.

[0012] The image acquisition device 11 and / or the obstacle detection device 12 function as an environment detection device, detecting the vehicle's surroundings, including obstacles present in the vehicle's vicinity. The obstacles present in the vehicle's vicinity include other vehicles ahead of the vehicle in the lane it is traveling in (for example, including a vehicle ahead and a vehicle in front of the vehicle ahead), and another vehicle (also referred to as an adjacent vehicle) in a neighboring lane adjacent to the lane in which the vehicle is traveling.

[0013] The control input device 14 is configured to receive various operating inputs made by a vehicle occupant, for example, a driver, at the control unit 20. The control input device 14 includes an ACC switch, which is operated by the driver to activate and deactivate an ACC function, described below, and an adjustment switch to set, for example, a vehicle speed and a vehicle following distance within the ACC function. The control input device 14 is configured, for example, as a steering wheel switch on a steering wheel (not shown). The control input device 14 can also be configured as a touch panel, which is integrated, for example, with a display of the alarm unit 50, described below. The control input device 14 can also be configured so that multiple functions are assigned to one switch.

[0014] Vehicle-to-vehicle communication function 15 is a function for sending and receiving information between the vehicle and other vehicles in its vicinity, and includes a transmitter and a receiver. Vehicle-to-vehicle communication function 15 is configured to receive information about the driving states of other vehicles from other vehicles. This information includes, for example, the speeds of other vehicles and the positional relationships between other vehicles and lanes.

[0015] The control unit 20 is configured as a computer that includes, for example, a ROM memory that stores a program, data, and the like; a CPU that performs calculations; RAM memory that stores dynamic data and calculation results; an input / output interface; and the like. The control unit 20 is configured to perform functions of an ACC control unit 21, a destination control unit 22, a notification control unit 23, and the like, and performs the overall control of the driver assistance system 10. Details of the control by the control unit 20 are described below.

[0016] The braking device 30 is a braking device that generates a braking force in accordance with the amount of actuation of a brake pedal (not shown) by the driver and includes a brake control and a brake actuator to generate the braking force in response to a braking command from a vehicle system or the control unit 20.

[0017] The drive device 40 is configured to generate a driving force to propel the vehicle and includes an engine control unit (not shown) that controls the driving force according to the amount of depressurization of an accelerator pedal (not shown) by the driver, or in response to a control command from the control unit 20. It should be noted that an internal combustion engine, motor, or the like can be used as the vehicle's drive device 40.

[0018] The warning device 50 is configured to provide information to the vehicle occupants in response to a command from the control unit 20. The warning device 50 comprises a liquid crystal display, an indicator light, or the like, which is located in an instrument panel at the front of the vehicle and provides visual information to the occupants. The warning device 50 can, for example, be configured as a display for a navigation system that is not shown. The warning device 50 can also be configured to provide information to the occupants audibly, for example, via a loudspeaker, instead of visually via a display.

[0019] Next, the control by the control unit 20 is described in detail. The control unit 20 is configured to execute an ACC function via the ACC control unit 21 based on image data of an area in front of the vehicle, which is input from the image acquisition device 11, a distance between the vehicle and an obstacle, which is input from the obstacle detection device 12, and the like.

[0020] If there is no vehicle ahead in a lane where the vehicle is traveling with the ACC function activated, the ACC control unit 21 controls the braking device 30 and the drive device 40 to maintain a constant speed corresponding to a set vehicle speed (target vehicle speed) entered by the operating input device 14. Conversely, if there is a vehicle ahead in a lane where the vehicle is traveling with the ACC function activated, the ACC control unit 21 controls the braking device 30 and the drive device 40 to follow the vehicle ahead while maintaining a set vehicle-to-vehicle distance entered by the operating input device 14. The ACC control unit 21 thus acts as a distance control unit between vehicles.

[0021] The ACC function is configured to activate within a specific speed range (approximately 0 km / h to approximately 100 km / h). It should be noted that the ACC function is configured to temporarily stop activation when the accelerator pedal is pressed and to stop activation when the brake pedal is pressed.

[0022] During adaptive cruise control (ACC) operation, the host vehicle automatically brakes to maintain the set following distance when the vehicle ahead decelerates, while simultaneously accelerating to maintain the set following distance at or below a set speed when the vehicle ahead accelerates. Therefore, ACC controls the host vehicle to maintain following distance even when the vehicle ahead is in an abnormal driving condition, such as driving very close to one side of the lane or traveling at a significantly lower speed than the surrounding traffic flow.

[0023] If the vehicle ahead is in an abnormal driving condition, such as driving very close to one side of the lane or traveling at a speed abnormally lower than the surrounding traffic flow, it is assumed that the driver of the vehicle ahead is looking to the side or nodding off and not concentrating on driving. If the host vehicle continues following the vehicle ahead in such a condition, the host vehicle may find itself in a dangerous situation, for example, a collision caused by the vehicle ahead due to unexpected sudden braking.Therefore, in the present embodiment, the driver assistance system 10 informs or warns the driver of the host vehicle that it is advisable to overtake the vehicle ahead if it is in an abnormal driving condition. For example, the driver assistance system 10 is configured to display a notification on the message device 50 prompting the driver to overtake the vehicle ahead when it is determined that the vehicle ahead is in an abnormal driving condition.

[0024] The control unit 20, in addition to the ACC control unit 21, also includes the destination unit 22 and the notification control unit 23 and is configured to provide the driver of the host vehicle with appropriate information and to support the driver's driving operations when the vehicle ahead is in an abnormal driving condition. Here, an abnormal driving condition of the vehicle ahead means that the driving condition of the vehicle ahead is not normal and that dangerous behavior of the vehicle ahead could endanger the host vehicle. Although Fig. Figure 1 shows that the control unit 20 comprises the ACC control unit 21, the destination unit 22 and the notification control unit 23. It should be noted that the ACC control unit 21, the destination unit 22 and the notification control unit 23 may be implemented as an integral part of the control unit 20 or individually as separate control units.

[0025] The detection unit 22 is configured to determine, based on information about the vehicle ahead detected by the image acquisition device 11 and the obstacle detection device 12, whether the driving condition of the vehicle ahead is normal or not. The detection unit 22 determines whether the driving condition of the vehicle ahead is normal or abnormal based on factors such as: (1) Position of the vehicle ahead on the lane (2) Difference between the speeds of the vehicle ahead and the traffic flow in the surrounding area (3) Combination of the position of the vehicle ahead and the speed difference of the vehicle ahead

[0026] The following describes the determination of the driving condition of the vehicle ahead by the determination unit 22 with reference to Fig. 2, Fig. 3 to Fig. 4 described in detail. Fig. Figure 2 is a diagram showing the vehicle and the vehicle ahead of it, which is in the lane the vehicle is traveling in. Fig. Figure 3 is a diagram showing the vehicle, the vehicle ahead, and another vehicle in an adjacent lane, and Fig. Figure 4 is a diagram showing the vehicle, the vehicle in front, and a vehicle in front of the vehicle in front. Fig. 2, Fig. 3 to Fig. Figure 4 illustrates the vehicle's driving conditions under left-hand traffic rules. Although the following description uses left-hand traffic rules as examples, it is understood that the present embodiment is also applicable to right-hand traffic rules. (1) Position of the vehicle ahead on the lane

[0027] Fig. Figure 2 represents a road with one lane L1 and one lane L2, where lane L1 is defined by left and right boundary lines (white lines) M1 and M2, and lane L1 and lane L2 are separated by boundary line (white line) M2. As in Fig. As shown in Figure 2, a vehicle (host vehicle) 1 is traveling in lane L1, and a preceding vehicle 2 is located in front of vehicle 1. Vehicle 1 is traveling essentially along a center line M0 of lane L1, while the preceding vehicle 2 is traveling very close to one side of lane L1. The preceding vehicle 2 is traveling close to the left side of lane L1, that is, away from the adjacent lane L2.

[0028] The determination unit 22 performs image processing based on image data of an area in front of vehicle 1, which is input, for example, by the image acquisition device 11, and calculates the center line M0, which runs through the midpoint between the left and right boundary lines M1 and M2 of lane L1, in which vehicle 1 is traveling. The determination unit 22 calculates a distance (displacement) X1 between a center line N1 of vehicle 1 in the front-to-rear direction and the center line M0 of lane L1, and a distance (displacement) X2 between a center line N2 of the preceding vehicle 2 in the front-to-rear direction and the center line M0 of lane L1. The distances X1 and X2 represent the position of vehicle 1 and the preceding vehicle 2, respectively, on lane L1.The distances X1 and X2 from the center line M0 are represented by positive values ​​for the right side relative to the center line M0 of lane L1 (the side closest to the neighboring lane L2) or by negative values ​​for the left side (the side furthest from the neighboring lane L2).

[0029] The determination unit 22 determines that the preceding vehicle 2 is in an abnormal driving condition if the centerline N2 of the preceding vehicle 2 is to the left of the centerline M0 of the lane L1, an absolute value of the distance X2 of the preceding vehicle 2 is greater than or equal to a predetermined value A1 (X2 ≤ -A1), and the vehicle 1 is traveling substantially along the centerline M0 of the lane L1 (-A0 < X1 < A0). Here, the predetermined value A1 is a value used to determine that the preceding vehicle 2 is very close to the side (M1) of the lane L1 and is, for example, set to approximately 1.0 m. The predetermined value A0 is a value used to determine that the vehicle 1 is traveling substantially in the center of the lane L1 and is, for example, set to approximately 0.5 m. It should be noted that the predetermined values ​​A1 and A0 are also adjusted to appropriate values ​​taking into account the road width.

[0030] The determination unit 22 determines the abnormal driving condition of the vehicle 2 ahead by determining that the vehicle 2 ahead is traveling on the left side of lane L1 and checks whether or not vehicle 1 can safely overtake the vehicle 2 ahead. In other words, if the vehicle 2 ahead is traveling on the left side, that is, the side of lane L1 furthest from the adjacent lane L2, vehicle 1 can overtake the vehicle 2 ahead on the right side of the vehicle 2 ahead, that is, on the side adjacent to the adjacent lane L2, with ample clearance, even if the vehicle 2 ahead performs a sudden steering maneuver to the right.On the other hand, if the vehicle 2 ahead is traveling on the right-hand side, that is, on the side of lane L1 closest to the adjacent lane L2, vehicle 1, which is about to overtake vehicle 2 on its right-hand side, may come into contact with vehicle 2 if vehicle 2 makes a sudden right-hand steering maneuver. Therefore, the determination unit 22 is configured to determine that the driving condition of vehicle 2 ahead is abnormal if it is possible to determine that vehicle 1 can safely overtake vehicle 2 ahead.

[0031] The determination unit 22 also defines an abnormal condition as one in which the preceding vehicle 2 is traveling very close to one side while vehicle 1 is traveling normally, by determining that vehicle 1 is traveling substantially along the center line M1 of lane L1. For example, if vehicle 1 is traveling very close to one side like the preceding vehicle 2, it is possible that they are attempting to avoid an obstacle located in lane L1. Therefore, it is determined that only the preceding vehicle 2 is in an abnormal driving condition by considering the distance X1 of vehicle 1 from the center line M0. It is desirable that the determination unit 22 uses mean values ​​over a predetermined time period (for example, approximately 1 to 2 minutes) as the distance X1 of vehicle 1 and the distance X2 of the preceding vehicle 2.This reduces the need to determine that the driving condition of the vehicle 2 ahead is abnormal, for example, due to a momentary change in steering behavior. (2) Difference between the speeds of the vehicle ahead and the traffic flow in the surrounding area

[0032] Fig. Figure 3 shows another vehicle 3 that is present in the adjacent lane L2, in addition to vehicle 1 and the preceding vehicle 2, which are traveling in lane L1. This other vehicle 3 is a neighboring vehicle 3 traveling in the same direction as vehicle 1 and the preceding vehicle 2 in the adjacent lane L2.

[0033] The determination unit 22 calculates a vehicle speed V2 of the preceding vehicle 2 and a vehicle speed V3 of the adjacent vehicle 3 based on temporal changes in distances between vehicle 1 and obstacles, which are input, for example, from the obstacle detection device 12. The determination unit 22 can detect the vehicle speed V2 of the preceding vehicle 2 and the vehicle speed V3 of the adjacent vehicle 3 using the vehicle-to-vehicle communication function 15. The determination unit 22 determines whether the preceding vehicle 2 is traveling in accordance with the traffic flow in the vicinity of vehicle 1 by comparing the vehicle speed V2 of the preceding vehicle 2 with the vehicle speed V3 of the adjacent vehicle 3.The determination unit 22 determines that the driving condition of the vehicle 2 ahead is abnormal if the vehicle 2 ahead is traveling at a speed that is significantly lower than that of the traffic flow in the surrounding area.

[0034] The determination unit 22 calculates, for example, a speed difference ΔV (ΔV = Δ3 - Δ2) between the vehicle speed V2 of the vehicle ahead 2 and the vehicle speed V3 of the adjacent vehicle 3. The determination unit 22 determines that the driving condition of the vehicle ahead 2 is abnormal if the vehicle speed V2 of the vehicle ahead 2 is lower than the vehicle speed V3 of the adjacent vehicle 3 and the speed difference ΔV between the vehicle speed V2 of the vehicle ahead 2 and the vehicle speed V3 of the adjacent vehicle 3 is greater than or equal to a predetermined value B1 (for example, approximately 40 km / h).Here, the vehicle speed V3 of the adjacent vehicle 3 is a value representing the traffic flow in the vicinity of vehicle 1 and is a speed less than or equal to a speed limit on the road on which vehicle 1 is traveling. It is desirable that the determination unit 22 uses average values ​​over a predetermined time period (for example, approximately 1 to 2 minutes) as the vehicle speed V2 of the preceding vehicle 2 and as the vehicle speed V3 of the adjacent vehicle 3. This reduces the need to determine that the driving condition of the preceding vehicle 2 is abnormal, for example, due to an instantaneous change in its vehicle speed.

[0035] Fig. Figure 4 shows another vehicle 4 that is located in front of vehicle 2, in addition to vehicle 1 and the preceding vehicle 2, which are traveling in lane L1. This other vehicle 4 is a vehicle ahead of vehicle 2, traveling in the same direction as vehicle 1 and the preceding vehicle 2. The determining unit 22 detects the vehicle speed V4 of vehicle 4 ahead of the preceding vehicle, for example, by using the vehicle-to-vehicle communication function 15.If the image acquisition device 11 or the obstacle detection device 12 can detect vehicle 4 in front of the vehicle ahead because the vehicle ahead 2 is driving close to one side in lane L1 or the body of vehicle 4 in front of the vehicle ahead is larger than that of vehicle 2, the vehicle speed V4 of vehicle 4 in front of the vehicle ahead can be calculated based on data input from the image acquisition device 11 or the obstacle detection device 12.

[0036] The determination unit 22 calculates, for example, a speed difference ΔV (ΔV = Δ4 - Δ2) between the vehicle speed V2 of the vehicle 2 ahead and the vehicle speed V4 of the vehicle 4 in front of the vehicle 2 ahead. The determination unit 22 determines that the driving condition of the vehicle 2 ahead is abnormal if the vehicle speed V2 of the vehicle 2 ahead is lower than the vehicle speed V4 of the vehicle 4 in front of the vehicle 2 ahead, and the speed difference ΔV between the vehicle speed V2 of the vehicle 2 ahead and the vehicle speed V4 of the vehicle 4 in front of the vehicle 2 ahead is greater than or equal to the predetermined value B1 (for example, B1 = approximately 40 km / h).Here, the speed V4 of vehicle 4 ahead of the vehicle in front is a value representing the traffic flow in the vicinity of vehicle 1 and is a speed less than or equal to the speed limit on the road on which vehicle 1 is traveling. It is desirable that the determination unit 22 uses average values ​​over a predetermined time period (for example, approximately 1 to 2 minutes) for the vehicle speed V2 of the vehicle in front 2 and the vehicle speed V4 of vehicle 4 ahead of the vehicle in front. This reduces the need to determine that the driving condition of the vehicle in front 2 is abnormal, for example, due to an instantaneous change in vehicle speed.

[0037] In this way, the determination unit 22 determines that the driving condition of the vehicle 2 ahead is abnormal if the vehicle speed V2 of the vehicle 2 ahead is extremely low compared to the traffic flow in the vicinity of vehicle 1, which includes, for example, the adjacent vehicle 3 and the vehicle 4 ahead of the vehicle 2 ahead. The determination unit 22 determines the abnormal driving condition of the vehicle 2 ahead by taking into account that the vehicle 2 ahead is extremely slow compared to the traffic flow and checks whether vehicle 1 can safely overtake the vehicle 2 ahead.In other words, if the vehicle speed V2 of the vehicle 2 ahead is extremely low, any change in the behavior of the vehicle 2 ahead, even if it makes a sudden right-hand steering maneuver, will occur only gradually, and vehicle 1 can overtake the vehicle 2 ahead on its right with plenty of space. On the other hand, if the vehicle speed V2 of the vehicle 2 ahead is extremely high, the behavior of the vehicle 2 ahead will also change suddenly if it makes a sudden right-hand steering maneuver, so there is a possibility that vehicle 1, which is about to overtake the vehicle 2 ahead on its right, will come into contact with the vehicle 2 ahead.Therefore, the determination unit 22 is configured to determine that the driving condition of the vehicle 2 ahead is abnormal, if it is possible to determine that vehicle 1 can safely overtake the vehicle 2 ahead. (3) Combination of the position of the vehicle ahead and the speed difference of the vehicle ahead

[0038] The determination unit 22 can determine, based on a combination of the position of the vehicle 2 ahead on the lane L1 and the speed difference ΔV between the vehicle 2 ahead and the traffic flow in the surrounding area, whether the driving condition of the vehicle 2 ahead is abnormal or not. Fig. Figure 5 is an example of a diagram for determining the driving state of the vehicle 2 ahead based on the position of the vehicle 2 ahead and the speed difference ΔV of the vehicle 2 ahead. The horizontal axis in Fig. Figure 5 represents the distance X2 from the center line M0 of lane L1 to the center line N2 of the vehicle 2 ahead, and the vertical axis represents the speed difference ΔV between the speed V2 of the vehicle 2 ahead and the speed of another vehicle. M0, M1, and M2 on the horizontal axis correspond to the center line, the left end, and the right end of lane L1, respectively. The speed of another vehicle is, for example, the speed V3 of the adjacent vehicle 3 or the speed V4 of the vehicle 4 ahead of the vehicle 2 ahead.

[0039] In the image of Fig. 5 is a region R1 enclosed by the dashed line, a region representing an abnormal condition determined based on the distance X2 of the preceding vehicle 2 from the lane centerline M0, as described above in (1). If the distance X2 of the preceding vehicle 2 lies within region R1, the driving condition of the preceding vehicle 2 is determined to be an abnormal condition (X2 ≤ -A1). In this case, the abnormal condition of the preceding vehicle 2 can be determined by considering that the vehicle 1 is traveling substantially along the lane centerline M0 (-A0 < X1 < A0), as described above.

[0040] In the image of Fig. 5 is a region R2 enclosed by the dotted line, a region representing an abnormal condition determined on the basis of the speed difference ΔV between the vehicle 2 ahead and the surrounding traffic flow, as described above in (2). If the speed difference ΔV between the vehicle speed V2 of the vehicle 2 ahead and the vehicle speed V3 of the adjacent vehicle 3, or the speed difference ΔV between the vehicle speed V2 of the vehicle 2 ahead and the vehicle speed Δ4 of the vehicle 4 ahead of the vehicle 2 ahead, lies within the region R2, the driving condition of the vehicle 2 ahead is determined to be an abnormal condition (ΔV ≥ B1).

[0041] In the image of Fig. 5 is a region R3, enclosed by the dashed line, representing an abnormal condition determined based on the distance X2 of the preceding vehicle 2 from the lane centerline M0 and the speed difference ΔV relative to the surrounding traffic flow. If the distance X2 of the preceding vehicle 2 from the lane centerline M0 is greater than or equal to the predetermined value A1, and the speed difference between the preceding vehicle 2 and the surrounding traffic flow is greater than or equal to a predetermined value B2, the determination unit 22 determines that the driving condition of the preceding vehicle 2 is abnormal (X2 ≥ A1 and ΔV ≥ B2). Here, the predetermined value B2 is less than the predetermined value B1 used to determine the region R2 above (for example, B2 = approximately 30 km / h).In other words, the determination unit 22 determines that the driving condition of the vehicle 2 ahead is abnormal if the vehicle 2 ahead is driving close to the right-hand side of lane L1 at a speed that is slightly slower than the flow of traffic.

[0042] If the vehicle ahead (vehicle 2) is driving close to the right side of lane L1, which is the side closest to the adjacent lane L2, there is a possibility that vehicle 1 will collide with vehicle 2 while overtaking, as described above. However, if vehicle 2 is driving extremely close to the right side of lane L1, it is assumed that the driver of vehicle 2 is looking to the side or nodding off and not concentrating on driving.If the vehicle speed V2 of the vehicle 2 ahead is somewhat lower than the average traffic flow in the surrounding area, a determination is made, taking into account the risk of following the vehicle 2 ahead, which is exhibiting dangerous behavior, and the risk of a side collision with the vehicle 2 ahead due to a sudden steering maneuver by the vehicle 2 ahead while overtaking, as to whether the driving condition of the vehicle 2 ahead is abnormal or not. The determination unit 22 determines that the vehicle 2 ahead is driving extremely close to the right side of lane L1 and that safe overtaking of the vehicle 2 ahead is possible if X2 ≥ A1 and ΔV ≥ B2, and therefore determines that the driving condition of the vehicle 2 ahead is abnormal.

[0043] The determination unit 22 determines, based on the distance X2 from the center line M0 of lane L1 to the center line N2 of the vehicle ahead 2 and the speed difference ΔV between the vehicle speed V2 of the vehicle ahead 2 and the vehicle speed of another vehicle, that the driving condition of the vehicle ahead 2 is abnormal if the combination of the distance X2 and the speed difference ΔV within one of the in Fig. The area R1 to R3 shown in the diagram is located in the 5. In this way, the determination unit 22 determines whether the driving condition of the vehicle 2 ahead is abnormal, also taking into account whether it is possible for vehicle 1 to safely overtake the vehicle 2 ahead.

[0044] The notification control unit 23 is configured to control the message device 50 to display a notification prompting the driver to overtake the vehicle 2 ahead when the determination unit 22 determines that the driving condition of the vehicle 2 ahead is abnormal. The message device 50 displays the notification prompting the driver to overtake the vehicle 2 ahead in response to a command from the notification control unit 23 when the driving condition of the vehicle 2 ahead is abnormal and the vehicle 2 ahead is exhibiting dangerous behavior. The overtaking notification is expressed, for example, through text or an illustration.The notification control unit 23 can, in addition to a notification prompting the driver to overtake the vehicle 2 ahead, provide a notification prompting the driver to change vehicles ahead that the vehicle is following. Furthermore, the notification control unit 23 can provide a notification indicating that the driving condition of the vehicle 2 ahead is abnormal. The driver, seeing the notification displayed on the message device 50, understands that the driving condition of the vehicle 2 ahead is abnormal and that overtaking is recommended, and voluntarily performs a driving operation to overtake the vehicle 2 ahead.

[0045] The following describes the sequence of events for the notification control, which in the present embodiment is implemented according to the driving state of the vehicle 2 ahead, based on the flowchart in Fig. 6 described. Fig. Figure 6 is an example of the notification control processing that is periodically executed by control unit 20 during activation of the follow-up driving control of the ACC function.

[0046] In step S101, the control unit 20 acquires information regarding the environment of the vehicle 1, which is detected by the image acquisition device 11 and the obstacle detection device 12.

[0047] In step S102, the determination unit 22 performs image processing on image data in an area in front of vehicle 1 and calculates the distance X1 between the center line N1 of vehicle 1 and the center line M0 of lane L1, and the distance X2 between the center line N2 of the preceding vehicle 2 and the center line M0 of lane L1. It should be noted that vehicle 1 follows the preceding vehicle 2 via the follow-through control system, and the preceding vehicle 2 is a target vehicle of the follow-through system.

[0048] In step S103, the determination unit 22 calculates the speed difference ΔV between the vehicle speed V2 of the vehicle 2 ahead and the vehicle speed of another vehicle located in the vicinity of the vehicle 2 ahead. If the adjacent vehicle 3 is located in the adjacent lane L2, as in Fig. As shown in Figure 3, the determining unit 22 calculates the speed difference ΔV (= V3 - V2) between the vehicle speed V3 of the adjacent vehicle 3 and the vehicle speed V2 of the preceding vehicle 2. If vehicle 4 is in front of the preceding vehicle 2, as shown in Figure 3, the speed difference ΔV is calculated as follows: Fig. As shown in Figure 4, the determination unit 22 calculates the speed difference ΔV (= V4 - V2) between the vehicle speed V4 of vehicle 4 in front of the preceding vehicle and the vehicle speed V2 of the preceding vehicle 2. If both the adjacent vehicle 3 and vehicle 4 in front of the preceding vehicle are present, the determination unit 22 can use an average of the speed difference to the adjacent vehicle 3 and the speed difference to vehicle 4 in front of the preceding vehicle, or it can use one of the values ​​of the speed difference to the adjacent vehicle 3 and the speed difference to vehicle 4 in front of the preceding vehicle as the speed difference ΔV to the vehicle speed of another vehicle.

[0049] In step S104, the determination unit 22 determines whether the driving state of the preceding vehicle 2 is within the range shown in the image of Fig. The determination unit 22 determines whether the vehicle 2 is within the area R1 shown in step 5. It compares the distance X2 of the preceding vehicle 2, calculated in step S102, with the predetermined value A1 and compares the distance X1 of vehicle 1 with the predetermined value A0. If the preceding vehicle 2 is close to the left side of lane L2 relative to the center line M0 of lane L1 (X2 ≤ -A1) and vehicle 1 is traveling substantially along the lane center line M0 (-A0 < X1 < A0), the determination unit 22 determines that the driving condition of the preceding vehicle 2 is within the area R1. In this case, it is determined that the preceding vehicle 2 is traveling extremely close to the left side of lane L1, that is, on the side furthest from the adjacent lane L2, and that the driving condition is abnormal, and the processing proceeds to step S107.On the other hand, if the determination in step S104 is negative, the processing proceeds to step S105.

[0050] In step S105, the determination unit 22 determines whether the driving state of the preceding vehicle 2 is within the area R2 in the image of Fig. The determination unit 22 compares the speed difference ΔV between the vehicle 2 ahead and another vehicle, calculated in step S103, with the predetermined value B1. If the vehicle 2 ahead is traveling at a speed significantly lower than that of another vehicle in the vicinity (ΔV ≥ B1), the determination unit 22 determines that the driving condition of the vehicle 2 ahead is within range R2. In this case, it is determined that the vehicle 2 ahead is traveling at an extremely low speed compared to the traffic flow and that the driving condition is abnormal, and the processing proceeds to step S107. On the other hand, if the determination in step S105 is negative, the processing proceeds to step S106.

[0051] In step S106, the determination unit 22 determines whether the driving state of the preceding vehicle 2 is within the area R3 in the image of Fig. The determination unit 22 compares the distance X2 of the vehicle 2 ahead with the predetermined value A1 and compares the speed difference ΔV between the vehicle 2 ahead and another vehicle with the predetermined value B2. If the vehicle 2 ahead is close to the right side of lane L2 relative to the center line M0 of lane L1 (X2 ≥ A1) and is traveling at a slightly lower speed than another vehicle in the vicinity (ΔV ≥ B2), the determination unit 22 determines that the driving condition of the vehicle 2 ahead is within range R3.In this case, it is determined that the vehicle ahead, vehicle 2, is driving extremely close to the right side of lane L1, that is, on the side closest to the adjacent lane L2, at a speed lower than the traffic flow, and that the driving condition is abnormal, and the processing proceeds to step S107. On the other hand, if the determination in step S106 is negative, the processing is terminated.

[0052] In step S107, the notification control unit 23 controls the message device 50 to display a notification requesting that the vehicle ahead, vehicle 2, whose driving condition has been determined to be abnormal by the determination unit 22, be overtaken. This results in the Fig. Processing shown in section 6 has been completed.

[0053] The driver assistance system 10 according to the embodiment described above can achieve the following effects.

[0054] (1) The driver assistance system 10 comprises: the image capture device 11 and the obstacle detection device 12, which detect a surrounding area of ​​the vehicle 1 that includes the vehicle 2 ahead, which is on lane L1 in which the vehicle 1 is traveling; the determination unit 22, which is configured to determine, based on information about the vehicle 2 ahead detected by the image capture device 11 and the obstacle detection device 12, whether the driving condition of the vehicle 2 ahead is normal or not; and the notification control unit 23, which is configured to control the message device 50 to provide a notification requesting that the vehicle 2 ahead be overtaken if the determination unit 22 determines that the driving condition of the vehicle 2 ahead is abnormal.

[0055] If the vehicle ahead (vehicle 2) is in an abnormal driving condition, there is a possibility that the vehicle behind (vehicle 1) could be placed in a dangerous situation due to an unexpected driving action by the vehicle ahead (vehicle 2). If the driving condition of the vehicle ahead is determined to be abnormal, it is possible to allow the driver of vehicle 1 to recognize the abnormal driving condition of the vehicle ahead (vehicle 2) and to guide the driver towards an appropriate driving action by providing the notification requesting an overtaking maneuver.

[0056] (2) The determination unit 22 determines, based on the distance X2 between the centerline N2 of the vehicle 2 ahead (in the front-to-rear direction) and the centerline M0 of lane L1, and based on whether it is possible to safely overtake the vehicle 2 ahead, whether the driving condition of the vehicle 2 ahead is abnormal or not. The notification control unit 23 controls the reporting device 50 to provide a notification requesting that the vehicle 2 ahead be overtaken if the distance X2 between the centerline N2 of the vehicle 2 ahead and the centerline M0 of lane L1 is greater than or equal to the predetermined value A1 and it is determined that it is possible to safely overtake the vehicle 2 ahead.The driving condition of the vehicle 2 ahead is determined to be abnormal if it is possible to determine that vehicle 1 can safely overtake vehicle 2 ahead, and therefore the notification requesting that vehicle 1 overtake vehicle 2 ahead can also be provided taking into account the question of whether vehicle 1 can safely overtake vehicle 2 ahead.

[0057] (3) The determination unit 22 determines that it is possible to safely overtake the vehicle 2 ahead if the centerline N2 of the vehicle 2 ahead, relative to the centerline M0 of lane L1, is on the side of lane L1 furthest from the adjacent lane L2. The possibility of the vehicle 1 colliding laterally with the vehicle 2 ahead is considered low even if the vehicle 2 ahead, while in the process of overtaking the vehicle 2 ahead on the side of the adjacent lane L2, makes an unexpected steering maneuver towards the adjacent lane L2, provided that the vehicle 2 ahead is on the side furthest from the adjacent lane L2 relative to the centerline M0 of lane L1 and an absolute value of the distance X2 is greater than or equal to the predetermined value A1.In this way, the driving condition of the vehicle 2 ahead is determined to be abnormal if it is possible to determine that vehicle 1 can safely overtake vehicle 2 ahead, and therefore it is also possible, taking into account the question of whether vehicle 1 can safely overtake vehicle 2 ahead, to provide a notification requesting that vehicle 1 overtake vehicle 2 ahead.

[0058] (4) The determination unit 22 determines that the driving condition of the vehicle 2 ahead is abnormal if the vehicle speed V2 of the vehicle 2 ahead is lower than the vehicle speed V3, V4 of another vehicle 3, 4 located in the vicinity of the vehicle 2 ahead, and the speed difference ΔV between the vehicle speed V2 of the vehicle 2 ahead and the vehicle speed V3, V4 of another vehicle 3, 4 is greater than or equal to the predetermined value B1. A case in which the vehicle speed V2 of the vehicle 2 ahead is significantly lower than that of the traffic flow in the vicinity corresponds to a condition in which the driver of the vehicle 2 ahead is not performing a driving operation normally and, for example, is not concentrating on the driving operation.It is possible to allow the driver of vehicle 1 to recognize the abnormal driving condition of the vehicle 2 ahead and to guide the driver to an appropriate driving operation by providing, in such a condition, a notification requesting that the vehicle 2 ahead be overtaken.

[0059] (5) The driver assistance system 10 includes an ACC (adaptive cruise control) unit 21, which is configured to perform a following maneuver with respect to the vehicle ahead at a set vehicle-to-vehicle distance, which is maintained when the vehicle ahead 2 is in lane L1, in which the vehicle 1 is traveling. The determination unit 22 determines whether the driving condition of the vehicle ahead 2 is normal when the ACC control unit 21 performs the following maneuver. Even if the vehicle 1 is traveling behind the vehicle ahead 2 and the set vehicle-to-vehicle distance is maintained by the ACC function during the execution of the following maneuver, there is a possibility that the vehicle 1 may collide with the vehicle ahead 2 due to unexpected braking by the vehicle ahead 2, for example, if the vehicle ahead 2 is not driving normally.Therefore, it is possible to allow the driver of vehicle 1 to recognize the abnormal driving condition of the vehicle 2 ahead and to guide the driver to an appropriate driving operation by providing a notification that prompts overtaking when the driving condition of the vehicle 2 ahead is determined to be abnormal. Second embodiment

[0060] A driver assistance system 10 according to a second embodiment of the present invention is described below. A basic configuration of the driver assistance system 10 according to the second embodiment corresponds to that of the first embodiment described above. The main differences from the first embodiment are described below.

[0061] The first embodiment described above is configured such that the notification requesting the driver to overtake the vehicle 2 ahead is displayed on the message device 50 when the driving condition of the vehicle 2 ahead is determined to be abnormal. The second embodiment is configured to support a driver's driving operation by providing the driver of vehicle 1 with suitable information even when it is not possible to determine that the driving condition of the vehicle 2 ahead is abnormal. That is, the driver of vehicle 1 receives a notification requesting that the distance between the vehicle 2 ahead and vehicle 1 be increased if the vehicle 2 ahead is exhibiting dangerous behavior and it cannot be assumed that vehicle 1 can safely overtake the vehicle 2 ahead.

[0062] Fig. Figure 7 is an example of a diagram for determining the driving state of the vehicle 2 ahead, based on the position of the vehicle 2 ahead and a speed difference ΔV to the vehicle 2 ahead. The diagram in Fig. 7 contains, in addition to the image of Fig. 5, as described above in the first embodiment, defines a region R4 enclosed by the dashed-dotted line. Region R4 represents a condition in which the vehicle 2 ahead exhibits dangerous behavior, but it cannot be assumed that safe overtaking of the vehicle 2 ahead is possible. A determination unit 22 defines the condition in which safe overtaking cannot be assumed, even though the vehicle 2 ahead exhibits dangerous behavior, if the distance X2 of the vehicle 2 ahead from the lane centerline M0 is greater than or equal to a predetermined value A1 and the speed difference ΔV between the vehicle 2 ahead and the surrounding traffic flow is less than a predetermined value B2 (X2 ≥ A1 and ΔV < B2).

[0063] There is a possibility that vehicle 1 will collide laterally with vehicle 2 while overtaking if vehicle 2, as described above, is traveling close to the right side of lane L1, which is the side closest to the adjacent lane L2. The possibility of vehicle 1, which is about to overtake vehicle 2 on the right, making contact with vehicle 2 is also high if vehicle 2 is traveling at a high speed (V2) and suddenly makes a right-hand steering maneuver. In such a situation, it cannot be assumed that vehicle 1 will be able to overtake vehicle 2 safely.In other words, the driving condition of the vehicle 2 ahead is unsuitable for safe overtaking, although there is a high risk if vehicle 1 continues to follow vehicle 2 ahead in this condition. Determination unit 22 specifies that the behavior of the vehicle 2 ahead is dangerous and unsuitable for safe overtaking if the driving condition of the vehicle 2 ahead is within the range of area R4, that is, if the vehicle 2 ahead is traveling at high speed close to the right-hand side of lane L1.

[0064] If the determination unit 22 determines that the driving condition of the vehicle 2 ahead is within range R4, a notification control unit 23 controls a message device 50 to provide a notification requesting that the vehicle-to-vehicle distance between the vehicle 2 ahead and the vehicle 1 be increased. It should be noted that the notification control unit 23 can also provide a notification indicating that the vehicle 2 ahead is exhibiting dangerous behavior.

[0065] The driver, observing the display on the message device 50, understands that the vehicle 2 ahead is exhibiting dangerous behavior and voluntarily initiates a driving operation to increase the distance to the vehicle 2 ahead. It should be noted that, in response to a switch activation corresponding to the driver's intention to increase the distance between vehicles, and after the message control unit 23 has displayed the notification requesting that the distance to the vehicle 2 ahead be increased, the driver assistance system 10 can control a braking device 30 and a drive device 40 during the execution of an ACC function so that the distance to the vehicle 2 ahead is automatically increased.The driver assistance system 10 can perform brake and drive force control to automatically increase the distance to the vehicle 2 ahead after the notification requesting to increase the distance to the vehicle 2 ahead has been displayed, regardless of whether the driver intends to do so or not.

[0066] The following describes the sequence of events for the notification control, which in the present embodiment is implemented according to the driving state of the vehicle 2 ahead, based on the flowchart in Fig. 8 described. Fig. Figure 8 is an example of a notification control processing that is periodically executed by control unit 20 during the activation of the follow-up driving control of the ACC function. Since the processing is described in steps S101 to S107 in the flowchart of Fig. 8 of the items in the schedule of Fig. If the description corresponds to 6, it will be omitted.

[0067] If the determination in step S106 is negative, that is, if the driving condition of the vehicle ahead 2 does not correspond to any of the areas R1 to R3 in the image of Fig. If the value corresponds to 7, processing proceeds to step S111.

[0068] In step S111, the determination unit 22 determines whether the driving state of the preceding vehicle 2 is within the area R4 in the image of Fig. The determination unit 22 compares the distance X2 of the vehicle 2 ahead with the predetermined value A1 and compares the speed difference ΔV between the vehicle 2 ahead and another vehicle with the predetermined value B2. If the vehicle 2 ahead is close to the right side of lane L2 relative to the center line M0 of lane L1 (X2 ≥ A1) and is traveling at a relatively high speed compared to another vehicle in the vicinity (ΔV < B2), the determination unit 22 determines that the driving condition of the vehicle 2 ahead is within range R4.In this case, it is determined that the vehicle ahead, 2, is traveling at high speed extremely close to the right-hand side of lane L1, that is, on the side closest to the adjacent lane L2, and that the behavior of the vehicle ahead, 2, is dangerous but not suitable for safe overtaking, and the processing proceeds to step S112. On the other hand, if the determination in step S111 is negative, the processing is terminated.

[0069] In step S112, the notification control unit 23 controls the reporting device 50 to display a notification requesting that the distance to the vehicle 2 ahead, whose behavior has been determined by the detection unit 22 to be dangerous, be increased. This is done in Fig. Processing shown in section 8 has been completed.

[0070] The driver assistance system 10 according to the present embodiment described above can achieve the following effects in addition to the effects of the first embodiment described above.

[0071] The notification control unit 23 controls the reporting device 50 to provide the notification that requests an increase in the distance between the vehicle 2 ahead and the vehicle 1 when the distance X2 between the center line N2 of the vehicle 2 ahead and the center line M0 of lane L1 is greater than or equal to the predetermined value A1, and it is determined that it is not possible to safely overtake the vehicle 2 ahead. The vehicle 2 ahead exhibits dangerous behavior by driving close to one side of lane L1, but it is determined that it is not possible to safely overtake the vehicle 2 ahead.In such a situation, it is possible to enable the driver of vehicle 1 to recognize the dangerous behavior of the vehicle 2 ahead and to guide the driver towards an appropriate driving operation by prompting them to increase the distance to the vehicle 2 ahead. This makes it possible to support the driver's driving operation even if it is determined that it is not possible to safely overtake the vehicle 2 ahead. Third embodiment

[0072] A driver assistance system 10 according to a third embodiment of the present invention is described below. A basic configuration of the driver assistance system 10 according to the third embodiment corresponds to that of the first and second embodiments described above. The differences from the second embodiment are mainly described below.

[0073] In the second embodiment above, the determining unit 22 determines the driving state of the preceding vehicle 2 based on the information in Fig. Figure 7 shows the image. In the present embodiment, a determination unit 22 determines the driving state of a preceding vehicle 2 based on an image that differs from the image of Fig. 7 distinguishes. Fig. Figure 9 shows an example of an image for determining the driving state of the vehicle 2 ahead, based on the position of the vehicle 2 ahead and a speed difference ΔV to the vehicle 2 ahead. The image of Fig. 9 is designed to determine the driving condition based on the degree of anomaly of the vehicle ahead 2. The degree of anomaly of the vehicle ahead is defined, for example, as the greater the distance X2 of the vehicle ahead 2 from the center line M0 of a lane L1, that is, the closer the vehicle ahead 2 is to one end of the lane L1, and the greater the speed difference ΔV between the vehicle ahead 2 and the traffic flow in the surrounding area, that is, the lower the vehicle speed V2 of the vehicle ahead 2 is compared to the traffic flow in the surrounding area.

[0074] In the image of Fig. 9 is an area R10 enclosed by the dotted line, representing an average degree of anomaly of the vehicle 2 ahead. The determination unit 22 defines that the degree of anomaly of the vehicle 2 ahead is at the average level when the distance X2 of the vehicle 2 ahead from the lane centerline M0 and the speed difference ΔV between the vehicle 2 ahead and the surrounding traffic flow satisfy the following conditions. When the degree of anomaly is at the average level, the driving state of the vehicle 2 ahead is defined as a first state. −C2 <X2≤−C1, und ΔV<D1, −C2 <X2<C2, und D2≤ΔV<D1, or C1≤X2 <C2, und D3≤ΔV<D1

[0075] In the image of Fig. 9 is an area R20, enclosed by the dashed line, representing the high degree of anomaly of the vehicle 2 ahead. The determination unit 22 defines the degree of anomaly of the vehicle 2 ahead as high when the distance X2 of the vehicle 2 ahead from the lane centerline M0 and the speed difference ΔV between the vehicle 2 ahead and the surrounding traffic flow satisfy the following conditions. When the degree of anomaly is high, the driving state of the vehicle 2 ahead is defined as a second state. −C2≥X2, D1≤ΔV, or C2≤X2, and D3≤ΔV

[0076] Here, a predetermined value D1 of the speed difference ΔV is a threshold used to determine that the degree of anomaly of the vehicle ahead 2 is high, and is set, for example, to approximately 40 km / h to approximately 45 km / h. A predetermined value D2 of the speed difference ΔV is a threshold used to determine that the degree of anomaly of the vehicle ahead 2 is in the medium range, and is set, for example, to approximately 30 km / h to approximately 35 km / h. A predetermined value D3 of the speed difference ΔV is a threshold used to determine that the degree of anomaly of the vehicle ahead 2, in combination with the distance X2 of the vehicle ahead 2, is medium or high, and is set, for example, to approximately 25 km / h.Furthermore, a predetermined value C1 of the distance X2 of the preceding vehicle 2 is a threshold to determine that the degree of anomaly of the preceding vehicle 2 is in the medium range, and a predetermined value C2 of the distance X2 of the preceding vehicle 2 is a threshold to determine that the degree of anomaly of the preceding vehicle 2 is high. Predetermined values ​​C1 and C2 can be similar to those in the first embodiment above, or different values.

[0077] A notification control unit 23 controls a message device 50 to display a notification requesting an increase in the vehicle-to-vehicle distance when the determination unit 22 determines that the driving condition of the vehicle ahead 2 corresponds to range R10 and the degree of anomaly is of medium level. Conversely, the notification control unit 23 controls the message device 50 to display a notification requesting that the vehicle ahead 2 be overtaken when the determination unit 22 determines that the driving condition of the vehicle ahead 2 corresponds to range R10 and the degree of anomaly is high.

[0078] The determination unit 22 can determine the driving state of the preceding vehicle 2 based on the following conditions instead of the image of Fig. 9 determine. (i) The determination unit 22 determines that the degree of anomaly of the vehicle ahead 2 falls within a first range if the distance X2 of the vehicle ahead 2 from the lane centerline M0 is less than or equal to a first distance threshold (-C1) (if an absolute value of distance X2 is greater than or equal to the first distance threshold (C1)), or if the vehicle speed V2 of the vehicle ahead 2 is lower than the vehicle speed of any other vehicle 3, 4 and the speed difference ΔV is greater than or equal to a first speed difference threshold (ΔD2). The first range corresponds substantially to range R10 in the diagram of Fig. 9 is a range representing the average degree of anomaly. If the degree of anomaly falls into the first range, the driving state of the vehicle ahead, vehicle 2, is defined as the first state.

[0079] (ii) The determination unit 22 determines that the degree of anomaly of the vehicle ahead 2 falls into a second range if the distance X2 of the vehicle ahead 2 from the lane centerline M0 is less than or equal to a second distance threshold (-C2) (if the absolute value of the distance X2 is greater than or equal to the second distance threshold (C2) which is greater than the first distance threshold (C1)), or if the vehicle speed V2 of the vehicle ahead 2 is lower than the vehicle speed of another vehicle 3, 4 and the speed difference ΔV is greater than or equal to a second speed difference threshold (D1) which is greater than the first speed difference threshold (D2). The second range corresponds essentially to range R20 in the diagram of Fig.9 represents a high degree of anomaly. If the degree of anomaly falls into the second range, the driving condition of the vehicle ahead, vehicle 2, is defined as the second condition.

[0080] The driver assistance system 10 according to the present embodiment described above can achieve the following effects in addition to the effects of the first and second embodiments described above.

[0081] (1) The determination unit 22 calculates the degree of anomaly in the driving condition of the vehicle ahead 2 based on information about the vehicle ahead 2 detected by the image acquisition device 11 and the obstacle detection device 12. The determination unit 22 determines that the driving condition of the vehicle ahead 2 is the first condition if the calculated degree of anomaly falls within the first range (range R10), which represents the medium level, and determines that the driving condition of the vehicle ahead 2 is the second condition if the calculated degree of anomaly falls within the second range (range R20), which represents the high level.The notification control unit 23 controls the message device 50 to provide a notification prompting the driver to overtake the vehicle 2 ahead when the vehicle 2 ahead is in the second state, and to increase the distance between the vehicle 2 ahead and the vehicle 1 when the vehicle 2 ahead is in the first state. This makes it possible to provide the driver with an appropriate notification based on the degree of anomaly of the vehicle 2 ahead and to provide corresponding support while driving. The driving operation to overtake the vehicle 2 ahead requires a combination of acceleration / braking and steering maneuvers, which some drivers find difficult.It is possible to request the driver to overtake only in a situation where it is deemed necessary to avoid the dangerous vehicle 2 ahead, by limiting the notification requesting to overtake the vehicle 2 ahead to cases where the degree of anomaly of the vehicle 2 ahead is high.

[0082] (2) The determination unit 22 calculates the degree of anomaly of the driving condition of the vehicle ahead 2 based on the distance X2 between the centerline N2 of the vehicle ahead 2 in the front-to-rear direction and the centerline M0 of the lane L1, and the speed difference ΔV between the vehicle speed V2 of the vehicle ahead 2 and the vehicle speed V3, V4 of another vehicle 3, 4 present in the vicinity of the vehicle ahead 2. The determination unit 22 determines that the degree of anomaly falls into the first range (range R10) if the distance X2 is less than or equal to the first distance threshold (-C1), or if the vehicle speed V2 of the vehicle ahead 2 is lower than the vehicle speed V3, V4 of another vehicle 3, 4 and the speed difference ΔV is greater than or equal to the first speed difference threshold (ΔD2).The determination unit 22 determines that the degree of anomaly falls into the second range (range R20) if the distance X2 is less than or equal to the second distance threshold (-C2), which is lower than the first distance threshold (-C1), or if the vehicle speed V2 of the preceding vehicle 2 is less than the vehicle speed V3, V4 of another vehicle 3, 4 and the speed difference ΔV is greater than or equal to the second speed difference threshold (ΔD1), which is greater than the first speed difference threshold (ΔD2).In this way it can be determined that the degree of anomaly of the vehicle ahead is higher the closer the vehicle ahead 2 is to one end of lane L1 or the lower the vehicle speed V2 of the vehicle ahead 2 is compared to the traffic flow in the surroundings, and it is possible to request the overtaking of the vehicle ahead 2 in a situation where it is deemed necessary to avoid the dangerous vehicle ahead 2. Modifications

[0083] (1) In the embodiments described above, the example is described in which the notification requesting the driver to overtake the vehicle 2 ahead, or the notification requesting the driver to increase the distance between vehicles, is displayed during the activation of the following-drive control by the ACC function in the driver assistance system 10. However, the present invention is not limited to this and is also applicable, for example, to a case in which the driver assistance system 10 does not perform the following-drive control by means of the ACC function. For example, the message device 50 can be caused to display the notification requesting the driver to overtake the vehicle 2 ahead if the determination unit 22, in a state in which the vehicle 1 is following the vehicle 2 ahead through manual driving operations by the driver, determines that the driving state of the vehicle 2 ahead is abnormal.Furthermore, the present invention is also applicable to a case in which the driver assistance system 10 is not equipped with the ACC function.

[0084] (2) In the embodiments described above, the detection unit 22 determines whether the driving condition of the vehicle 2 ahead is abnormal or not based on the speed difference ΔV between the vehicle 2 ahead and the surrounding traffic flow. However, the present invention is not limited to this, and the driving condition can be determined based on the vehicle speed V2 of the vehicle 2 ahead instead of the speed difference ΔV. For example, the detection unit 22 can determine that the driving condition of the vehicle 2 ahead is abnormal if the vehicle 2 ahead is traveling at an extremely low speed, less than or equal to a predetermined value (for example, about 10 km / h to about 20 km / h), extremely close to one end of lane L1.If the speed V2 of the vehicle 2 ahead is extremely low, any change in the behavior of the vehicle 2 ahead will occur only slowly, even if the vehicle 2 ahead performs an unexpected steering operation. Therefore, the determining unit 22 can determine that a safe overtaking of the vehicle 2 ahead is possible. In other words, the determining unit 22 can determine that a safe overtaking of the vehicle 2 ahead is possible if the vehicle speed V2 of the vehicle 2 ahead is extremely (abnormally) low and less than or equal to the predetermined value.

[0085] (3) In the above embodiments, the notification requesting the driver to overtake the vehicle 2 ahead and the notification requesting the driver to increase the distance between vehicles are provided to the driver by display on the message device 50. However, the present invention is not limited to this, and the notification requesting the driver to overtake the vehicle 2 ahead and the notification requesting the driver to increase the distance between vehicles can be provided to the driver acoustically instead of or in addition to the notifications via the display.

[0086] (4) The determination unit 22 can determine whether the vehicle 2 ahead is driving close to one side of lane L1 or not, instead of on the basis of the distance from the lane center line M0, on the basis of the distances from the lane boundary lines M1 and M2 of lane L1.

[0087] Although embodiments of the present invention have been described, the present invention is not limited to the embodiments described above, and, as an additional note, various further modifications and changes to the scope of the present invention may be made. Reference symbol list 1 vehicle 2. Vehicle ahead 3 adjacent vehicles 4 vehicles ahead of the vehicle in front 10 Driver assistance systems 11 Image capture device (environmental detection device) 12 Obstacle detection device (environment detection device) 20 Control unit 21 ACC control unit (distance control unit) 22 Unit of determination 23 Notification control unit QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 6289669 B2

[0003]

Claims

Driver assistance system comprising: an environment detection device that detects the environment of a vehicle, including a vehicle ahead that is in a lane in which the vehicle is traveling; a determination unit configured to determine, based on information regarding the vehicle ahead detected by the environment detection device, whether the driving condition of the vehicle ahead is normal or not; and a notification control unit configured to control a message device to provide a notification prompting the driver to overtake the vehicle ahead when the determination unit determines that the driving condition of the vehicle ahead is abnormal. Driver assistance system according to claim 1, wherein: the determining unit determines whether the driving condition of the vehicle ahead is abnormal or not based on a distance between a center line of the vehicle ahead in a front-to-rear direction of the vehicle and a center line of the lane, and based on whether it is possible to safely overtake the vehicle ahead; and the notification control unit controls the reporting device to provide a notification requesting that the vehicle ahead be overtaken when the distance between the center line of the vehicle ahead and the center line of the lane is greater than or equal to a predetermined value, and it is determined that it is possible to safely overtake the vehicle ahead. Driving assistance system according to claim 2, wherein the determining unit determines that it is possible to safely overtake the vehicle ahead when the center line of the vehicle ahead is located relative to the center line of the lane on a side that is away from an adjacent lane which is adjacent to the lane. Driver assistance system according to claim 2, wherein the notification control unit controls the message device to provide a notification requesting an increase in the distance between the vehicle ahead and the vehicle when the distance between the center line of the vehicle ahead and the center line of the lane is greater than or equal to a predetermined value and it is determined that it is not possible to safely overtake the vehicle ahead. Driving assistance system according to one of claims 2 to 4, wherein the determining unit determines that it is possible to safely overtake the vehicle ahead when the vehicle speed of the vehicle ahead is an extremely low speed, less than or equal to a predetermined value. Driving assistance system according to one of claims 1 to 5, wherein the determining unit determines that the driving condition of the vehicle ahead is abnormal if the vehicle speed of the vehicle ahead is lower than the vehicle speed of another vehicle present in the vicinity of the vehicle ahead, and the speed difference between the vehicle speed of the vehicle ahead and the vehicle speed of the other vehicle is greater than or equal to a predetermined value. Driving assistance system according to claim 1, wherein: the determining unit calculates a degree of anomaly of the driving condition of the vehicle ahead based on the information regarding the vehicle ahead, which is detected by the environment detection devices; the determining unit defines the driving condition of the vehicle ahead as a first condition if the calculated degree of anomaly falls into a first range, which represents a medium level, and defines the driving condition of the vehicle ahead as a second condition if the calculated degree of anomaly falls into a second range, which represents a high level;and the notification control unit controls the message device to provide a notification requesting that the vehicle ahead be overtaken when the driving state of the vehicle ahead is the second state, and controls the message device to provide a notification requesting that the distance between the vehicle ahead and the vehicle be increased when the driving state of the vehicle ahead is the first state. Driving assistance system according to claim 7, wherein: the determining unit calculates a degree of anomaly of the driving condition of the vehicle ahead on the basis of a distance between a center line of the vehicle ahead in a front-rear direction of the vehicle and a center line of the lane as well as a speed difference between a vehicle speed of the vehicle ahead and a vehicle speed of another vehicle that is present in the vicinity of the vehicle ahead;and the unit of determination determines that the degree of anomaly falls into the first range if the distance is greater than or equal to a first distance threshold, or if the vehicle speed of the vehicle ahead is lower than the vehicle speed of the other vehicle and the speed difference is greater than or equal to a first speed difference threshold, and determines that the degree of anomaly falls into the second range if the distance is greater than or equal to a second distance threshold which is greater than the first distance threshold, or if the vehicle speed of the vehicle ahead is lower than the vehicle speed of the other vehicle and the speed difference is greater than or equal to a second speed difference threshold which is greater than the first speed difference threshold.; Driving assistance system according to one of claims 1 to 8, further comprising: a distance control unit configured to perform a following journey with respect to the vehicle ahead at a set vehicle-to-vehicle distance which is maintained when the vehicle ahead is in the lane on which the vehicle is traveling, wherein the determining unit determines whether the driving condition of the vehicle ahead is normal or not when the distance control unit performs the following journey.

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