Driver assistance systems

Abstract

In driver assistance systems, when the driving condition of the preceding vehicle is abnormal, the system appropriately assists the driver's driving operations. [Solution] The driving support system 10 includes surrounding environment detection devices 11 and 12 that detect the surrounding environment of the vehicle 1, including a preceding vehicle 2 that is in the lane L1 in which the vehicle 1 is traveling; a determination unit 22 configured to determine whether the driving state of the preceding vehicle 2 is normal or not based on the information of the preceding vehicle 2 detected by the surrounding environment detection devices 11 and 12; and a notification control unit 23 configured to control a notification device 50 to issue a notification prompting the preceding vehicle 2 to overtake if the determination unit 22 determines that the driving state of the preceding vehicle 2 is abnormal.

Description

Technical Field

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

Background Art

[0002] In order to support a driver's driving operation, an Adaptive Cruise Control (ACC) function that performs inter-vehicle distance control so that a vehicle follows a preceding vehicle while maintaining an appropriate inter-vehicle distance is known. During follow-up driving control with respect to a preceding vehicle, when the preceding vehicle accelerates or decelerates, the acceleration or deceleration of the vehicle is automatically controlled so as to maintain an appropriate inter-vehicle distance below the set vehicle speed. Regarding the follow-up driving control with the preceding vehicle, for example, Patent Document 1 discloses a device that detects dangerous behavior of the preceding vehicle and controls following and following cancellation with respect to the preceding vehicle. The device of Patent Document 1 detects at least one of speeding, sudden acceleration, sudden deceleration, wobbling, lane departure, too low vehicle speed, and too high vehicle speed as dangerous behavior of the preceding vehicle. When the dangerous behavior of the preceding vehicle is detected, the device of Patent Document 1 executes cancellation of following the preceding vehicle to prevent dangerous following driving.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the device described in Patent Document 1, when following the preceding vehicle is canceled, the driving operation switches to manual operation by the driver. That is, when following the preceding vehicle is canceled, the driver must manually operate the vehicle while the preceding vehicle is exhibiting dangerous behavior. Switching to manual operation in an abnormal driving state where the preceding vehicle is exhibiting dangerous behavior places a heavy burden on the driver. It is desirable to appropriately support the driver's driving operation when the preceding vehicle is exhibiting abnormal driving conditions.

[0005] This invention has been made in view of the above-described circumstances, and its purpose is to appropriately assist the driver's driving operations when the driving condition of the preceding vehicle is abnormal. [Means for solving the problem]

[0006] According to one aspect of the present invention, the driving assistance system includes: an ambient environment detection device that detects the surrounding environment of the vehicle, including a preceding vehicle located within the lane in which the vehicle is traveling; a determination unit configured to determine whether the driving state of the preceding vehicle is normal or not based on the information of the preceding vehicle detected by the ambient environment detection device; and a notification control unit configured to control a notification device to provide a notification prompting the preceding vehicle to overtake if the determination unit determines that the driving state of the preceding vehicle is abnormal. [Effects of the Invention]

[0007] The driver assistance system according to the present invention can appropriately assist the driver's driving operations when the driving condition of the preceding vehicle is abnormal. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a block diagram showing a schematic configuration of a driver assistance system in a first embodiment of the present invention. [Figure 2] Figure 2 shows a vehicle and a preceding vehicle located within the lane in which the vehicle is traveling. [Figure 3]Figure 3 shows a vehicle, a vehicle ahead, and other vehicles in the adjacent lane. [Figure 4] Figure 4 shows a vehicle, a preceding vehicle, and a vehicle further ahead of the preceding vehicle. [Figure 5] Figure 5 shows an example of a map used to determine the driving status of the preceding vehicle. [Figure 6] Figure 6 is a flowchart illustrating the notification control flow in the first embodiment. [Figure 7] Figure 7 shows an example of a map for determining the driving state of the preceding vehicle in the second embodiment. [Figure 8] Figure 8 is a flowchart illustrating the notification control flow in the second embodiment. [Figure 9] Figure 9 shows an example of a map for determining the driving state of the preceding vehicle in the third embodiment. [Modes for carrying out the invention]

[0009] -First Embodiment- Hereinafter, a driver assistance system according to the first embodiment of the present invention will be described in detail with reference to the drawings. Figure 1 is a block diagram showing the schematic configuration of the driver assistance system 10 in this embodiment. The driver assistance system 10 according to this embodiment is configured to assist the driving operations of the driver of the vehicle (also referred to as the vehicle) on which the driver assistance system 10 is installed.

[0010] As shown in Figure 1, the driver assistance system 10 includes an imaging device 11, an obstacle detection device 12, a vehicle speed sensor 13 for detecting the vehicle's speed, an operation input device 14, a vehicle-to-vehicle communication function 15, a control device 20, a braking device 30, a drive device 40, and a notification device 50.

[0011] The imaging device 11 is configured to capture images of the area surrounding the vehicle. The imaging device 11 is configured as a digital camera having an image sensor such as a CCD or CMOS, and is configured to output information of the area surrounding the vehicle as still images and / or moving images. The image data of the surrounding area captured by the imaging device 11 is input to the control device 20.

[0012] The obstacle detection device 12 is configured to detect obstacles around the vehicle and measure the relative distance (inter-vehicle distance) between the vehicle and the obstacle. Examples of obstacle detection devices 12 include millimeter-wave radar, sonar sensors, and LiDAR (Light Detection and Ranging). Distance measurement by the obstacle detection device 12 is performed dynamically at predetermined measurement cycles. The distance between the vehicle and the obstacle detected by the obstacle detection device 12 is input to the control device 20.

[0013] The imaging device 11 and / or obstacle detection device 12 function as an ambient environment detection device that detects the surrounding environment of the vehicle, including obstacles present around the vehicle. Obstacles present around the vehicle include other vehicles located ahead of the vehicle in the lane in which the vehicle is traveling (for example, a preceding vehicle traveling ahead of the vehicle, a vehicle traveling two vehicles ahead of the preceding vehicle), and other vehicles located in adjacent lanes adjacent to the lane in which the vehicle is traveling (also called adjacent vehicles).

[0014] The operation input device 14 is configured to receive various operation inputs to the control device 20 from the vehicle occupants, such as the driver. The operation input device 14 includes, for example, an ACC switch operated by the driver to switch the ACC function (described later) on and off, and a setting switch for setting the vehicle speed and distance between vehicles in the ACC function. The operation input device 14 is configured, for example, as a steering switch installed on the steering wheel (not shown). The operation input device 14 may also be configured, for example, as a touch panel integrated with the display of the notification device 50 (described later). Furthermore, it may be configured to assign multiple functions to a single switch.

[0015] The inter-vehicle communication function 15 is a function for transmitting and receiving information between a vehicle and other vehicles existing around the vehicle, and has a transmitter and a receiver. The inter-vehicle communication function 15 is configured to receive information regarding the driving state of other vehicles from the other vehicles. Information regarding the driving state of other vehicles includes, for example, the vehicle speed of other vehicles, the positional relationship between other vehicles and the lane, and the like.

[0016] The control device 20 is composed of, for example, a computer including a ROM that stores programs and data, a CPU that performs arithmetic processing, a RAM that stores dynamic data and arithmetic processing results, and an input / output interface. The control device 20 is configured to execute functions such as an ACC control unit 21, a determination unit 22, and a notification control unit 23, and to control the entire driving support system 10. Details of the control in the control device 20 will be described later.

[0017] The braking device 30 is a braking device that generates braking force according to the amount of depression of a brake pedal (not shown) by the driver, and includes a brake controller and a brake actuator for generating braking force according to a braking command from a vehicle system or the control device 20.

[0018] The driving device 40 is configured to generate a driving force for driving the vehicle, and includes an engine controller (not shown) that controls the driving force according to the amount of depression of an accelerator pedal (not shown) by the driver or according to a control command from the control device 20. As the driving device 40 of the vehicle, for example, an internal combustion engine, a motor, or the like can be used.

[0019] The notification device 50 is configured to provide information to the vehicle occupants in response to commands from the control device 20. The notification device 50 has, for example, a liquid crystal display, indicator lights, etc., located on the instrument panel at the front of the vehicle, and provides information to the occupants visually. The notification device 50 may be configured as, for example, a display for a navigation system (not shown). Instead of providing information visually through a display, the notification device 50 may be configured to provide information to the occupants auditorily, for example, by using a speaker, etc.

[0020] Next, the control in the control device 20 will be described in detail. The control device 20 is configured by the ACC control unit 21 to execute the ACC function based on image data of the area in front of the vehicle input from the imaging device 11 and the distance to obstacles input from the obstacle detection device 12.

[0021] When the ACC function is turned on and there is no preceding vehicle in the lane the vehicle is traveling in, the ACC control unit 21 controls the braking system 30 and the drive system 40 to maintain a constant speed according to the set vehicle speed (target vehicle speed) input from the operation input device 14. Also, when the ACC function is turned on and there is a preceding vehicle in the lane the vehicle is traveling in, the ACC control unit 21 controls the braking system 30 and the drive system 40 to maintain the set following distance input from the operation input device 14 and follow the preceding vehicle. The ACC control unit 21 functions as a vehicle distance control unit.

[0022] The ACC function is configured to operate within a predetermined vehicle speed range (for example, approximately 0 km / h to approximately 100 km / h). Furthermore, the ACC function is configured to temporarily deactivate when the accelerator pedal is operated, and to deactivate when the brake pedal is operated.

[0023] When the ACC function is active and following the vehicle ahead, if the vehicle ahead decelerates, the vehicle ahead will automatically decelerate to maintain the set distance, and if the vehicle ahead accelerates, the vehicle ahead will automatically accelerate to maintain the set distance at or below the set speed. Therefore, even in abnormal driving conditions, such as when the vehicle ahead is driving extremely close to the edge of the lane or driving at an extremely slow speed compared to the surrounding traffic flow, the ACC function controls the vehicle ahead to follow the vehicle ahead.

[0024] If a preceding vehicle is driving abnormally close to the edge of the lane or traveling at an abnormally slow speed compared to the surrounding traffic flow, it is possible that the driver of the preceding vehicle is distracted or drowsy and not concentrating on driving. If the vehicle continues to follow the preceding vehicle in such a state, the vehicle may be involved in a dangerous situation, such as a collision with the preceding vehicle due to an unexpected sudden deceleration. Therefore, in the driver assistance system 10 of this embodiment, when the preceding vehicle is driving abnormally, the driver of the vehicle is notified that it is desirable to overtake the preceding vehicle. For example, the driver assistance system 10 is configured to display a notification on the notification device 50 prompting the driver to overtake the preceding vehicle when it is determined that the preceding vehicle is driving abnormally.

[0025] The control device 20 includes an ACC control unit 21, a determination unit 22, and a notification control unit 23, and is configured to provide appropriate information to the driver of the vehicle when the preceding vehicle is in an abnormal driving state, thereby assisting the driver's driving operations. Here, an abnormal driving state of the preceding vehicle means that the preceding vehicle's driving state is not normal, and there is a possibility that the dangerous behavior of the preceding vehicle may endanger the vehicle. In Figure 1, the control device 20 is shown to include the ACC control unit 21, the determination unit 22, and the notification control unit 23, but the ACC control unit 21, the determination unit 22, and the notification control unit 23 may be implemented as an integrated unit of the control device 20, or they may be implemented as separate controllers.

[0026] The determination unit 22 is configured to determine whether the driving state of the preceding vehicle is normal or abnormal based on information about the preceding vehicle detected by the imaging device 11 and the obstacle detection device 12. The determination unit 22 determines whether the driving state of the preceding vehicle is normal or abnormal based on, for example, one of the following: (1) Position of the preceding vehicle within the lane (2) Speed ​​difference between the preceding vehicle and the surrounding traffic flow (3) Combination of the position of the preceding vehicle and the speed difference of the preceding vehicle

[0027] The determination of the driving state of the preceding vehicle by the determination unit 22 will be explained in detail below with reference to Figures 2 to 4. Figure 2 shows a vehicle and a preceding vehicle located in the lane in which the vehicle is traveling. Figure 3 shows a vehicle, a preceding vehicle, and another vehicle in an adjacent lane. Figure 4 shows a vehicle, a preceding vehicle, and a vehicle two vehicles ahead of the preceding vehicle. Figures 2 to 4 show the driving state of vehicles in a left-hand traffic lane. In the following explanation, the case where the traffic lane is left-hand traffic will be used as an example, but this embodiment is of course also applicable when the traffic lane is right-hand traffic.

[0028] (1) Position of the preceding vehicle within the lane Figure 2 shows a road containing lanes L1 and L2. Lane L1 is defined by left and right lane markings (white lines) M1 and M2, and lane L1 and lane L2 are separated by lane marking (white line) M2. As shown in Figure 2, vehicle 1 is traveling in lane L1, and vehicle 2 is ahead of vehicle 1. Vehicle 1 is traveling almost along the center line M0 of lane L1, but vehicle 2 is traveling extremely close to the edge of lane L1. Vehicle 2 is leaning towards the left edge of lane L1, that is, away from the adjacent lane L2.

[0029] The determination unit 22 performs image processing based on, for example, the image data of the front area of the vehicle 1 input from the imaging device 11, and calculates the center line M0 of the lane passing through the center position between the left and right dividing lines M1 and M2 of the lane L1 on which the vehicle 1 is traveling. The determination unit 22 calculates the distance (displacement) X1 between the center line N1 of the vehicle 1 in the longitudinal direction of the vehicle and the center line M0 of the lane L1, and the distance (displacement) X2 between the center line N2 of the preceding vehicle 2 in the longitudinal direction of the vehicle and the center line M0 of the lane L1. The distances X1 and X2 represent the positions of the vehicle 1 and the preceding vehicle 2 within the lane L1, respectively. The distances X1 and X2 from the center line M0 are represented by positive values on the right side (the side approaching the adjacent lane L2) with respect to the center line M0 of the lane L1 and negative values on the left side (the side moving away from the adjacent lane L2).

[0030] The determination unit 22 determines that the preceding vehicle 2 is in an abnormal driving state when the center line N2 of the preceding vehicle 2 is on the left side of the center line M0 of the lane L1, the absolute value of the distance X2 of the preceding vehicle 2 is equal to or greater than a predetermined value A1 (X2 ≦ -A1), and the vehicle 1 is traveling substantially along the center line M0 of the lane L1 (-A0 < X1 < A0). Here, the predetermined value A1 is a value for determining that the preceding vehicle 2 is extremely offset towards the end (M1) of the lane L1, and is set to, for example, about 1.0 m. The predetermined value A0 is a value for determining that the vehicle 1 is traveling substantially in the center of the lane L1, and is set to, for example, about 0.5 m. The predetermined values A1 and A0 are set to appropriate values in consideration of the road width as well.

[0031] The determination unit 22 determines whether the preceding vehicle 2 is in an abnormal driving state by considering whether vehicle 1 can safely overtake the preceding vehicle 2, based on the determination that the preceding vehicle 2 is traveling on the left side of lane L1. In other words, if the preceding vehicle 2 is traveling on the left side of lane L1, which is moving away from the adjacent lane L2, even if the preceding vehicle 2 makes a sudden steering maneuver to the right, vehicle 1 can overtake the preceding vehicle 2 from the right side, i.e., from the adjacent lane L2 side, with ample room to maneuver. On the other hand, if the preceding vehicle 2 is traveling on the right side of lane L1, which is moving towards the adjacent lane L2, and the preceding vehicle 2 makes a sudden steering maneuver to the right, there is a possibility that vehicle 1, which is attempting to overtake the preceding vehicle 2 from the right, will come into contact with the preceding vehicle 2. Therefore, the determination unit 22 is configured to determine that the driving state of the preceding vehicle 2 is abnormal when it can determine that vehicle 1 can safely overtake the preceding vehicle 2.

[0032] Furthermore, the determination unit 22 determines that vehicle 1 is traveling approximately along the center line M1 of lane L1, and that vehicle 1 is traveling normally, but if the preceding vehicle 2 is traveling extremely to one side, it is determined to be in an abnormal state. For example, if vehicle 1 is also traveling extremely to one side, similar to the preceding vehicle 2, it is possible that it is trying to avoid an obstacle located within lane L1. Therefore, by considering the distance X1 from the center line M0 of vehicle 1, the determination unit 22 determines that only the preceding vehicle 2 is in an abnormal driving state. It is desirable for the determination unit 22 to use the average value within a predetermined time (for example, about 1 to 2 minutes) as the distance X1 of vehicle 1 and the distance X2 of the preceding vehicle 2. This suppresses the determination that the driving state of the preceding vehicle 2 is abnormal due to, for example, instantaneous fluctuations in steering operation.

[0033] (2) Speed ​​difference between the preceding vehicle and the surrounding traffic flow Figure 3 shows vehicle 1 and preceding vehicle 2 traveling in lane L1, as well as another vehicle 3 in the adjacent lane L2. The other vehicle 3 is an adjacent vehicle traveling in the same direction as vehicle 1 and preceding vehicle 2 in the adjacent lane L2.

[0034] The determination unit 22 calculates the vehicle speed V2 of the preceding vehicle 2 and the vehicle speed V3 of the adjacent vehicle 3 based on the time change in the distance between vehicle 1 and the obstacle, which is input from the obstacle detection device 12. The determination unit 22 may also obtain 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. By comparing the vehicle speed V2 of the preceding vehicle 2 and the vehicle speed V3 of the adjacent vehicle 3, the determination unit 22 determines whether the preceding vehicle 2 is driving in accordance with the flow of traffic around vehicle 1. If the preceding vehicle 2 is driving at an extremely slow speed compared to the surrounding traffic flow, the determination unit 22 determines that the driving condition of the preceding vehicle 2 is abnormal.

[0035] For example, the determination unit 22 calculates the speed difference ΔV (ΔV = V3 - V2) between the speed V2 of the preceding vehicle 2 and the speed V3 of the adjacent vehicle 3. The determination unit 22 determines that the driving condition of the preceding vehicle 2 is abnormal if the speed V2 of the preceding vehicle 2 is smaller than the speed V3 of the adjacent vehicle 3, and the speed difference ΔV between the speed V2 of the preceding vehicle 2 and the speed V3 of the adjacent vehicle 3 is greater than or equal to a predetermined value B1 (for example, about 40 km / h). Here, the speed V3 of the adjacent vehicle 3 is a value representing the traffic flow around vehicle 1, and is below the speed limit of the road on which vehicle 1 is traveling. It is desirable for the determination unit 22 to use the average value within a predetermined time (for example, about 1 to 2 minutes) as the speed V2 of the preceding vehicle 2 and the speed V3 of the adjacent vehicle 3. This suppresses the determination that the driving condition of the preceding vehicle 2 is abnormal due to, for example, instantaneous fluctuations in vehicle speed.

[0036] Figure 4 shows vehicle 1 and preceding vehicle 2 traveling in lane L1, as well as another vehicle 4 located in front of preceding vehicle 2. The other vehicle 4 is a vehicle two vehicles ahead of preceding vehicle 2, traveling in the same direction as vehicle 1 and preceding vehicle 2. The determination unit 22 obtains the vehicle speed V4 of the vehicle two vehicles ahead of vehicle 4, for example, by using the vehicle-to-vehicle communication function 15. For example, if preceding vehicle 2 is traveling off-center within lane L1, or if the vehicle two vehicles ahead of vehicle 4 is larger than that of preceding vehicle 2, and the vehicle two vehicles ahead of vehicle 4 can be detected by the imaging device 11 or obstacle detection device 12, the vehicle speed V4 of the vehicle two vehicles ahead of vehicle 4 may be calculated based on the data input from the imaging device 11 or obstacle detection device 12.

[0037] For example, the determination unit 22 calculates the speed difference ΔV (ΔV = V4 - V2) between the speed V2 of the preceding vehicle 2 and the speed V4 of the vehicle two vehicles ahead 4. The determination unit 22 determines that the driving condition of the preceding vehicle 2 is abnormal if the speed V2 of the preceding vehicle 2 is smaller than the speed V4 of the vehicle two vehicles ahead 4, and the speed difference ΔV between the speed V2 of the preceding vehicle 2 and the speed V4 of the vehicle two vehicles ahead 4 is greater than or equal to a predetermined value B1 (for example, B1 = approximately 40 km / h). Here, the speed V4 of the vehicle two vehicles ahead 4 is a value representing the traffic flow around vehicle 1, and is below the speed limit of the road on which vehicle 1 is traveling. It is desirable for the determination unit 22 to use the average value within a predetermined time (for example, approximately 1 to 2 minutes) as the speed V2 of the preceding vehicle 2 and the speed V4 of the vehicle two vehicles ahead 4. This suppresses the determination that the driving condition of the preceding vehicle 2 is abnormal due to, for example, instantaneous fluctuations in vehicle speed.

[0038] Thus, the determination unit 22 determines that the driving condition of the preceding vehicle 2 is abnormal if the vehicle speed V2 of the preceding vehicle 2 is extremely slow relative to the traffic flow around vehicle 1, including adjacent vehicle 3 and the vehicle two vehicles ahead 4. The determination unit 22 determines the abnormal driving condition of the preceding vehicle 2 by considering whether vehicle 1 can safely overtake the preceding vehicle 2, based on the determination that the preceding vehicle 2 is extremely slow relative to the traffic flow. That is, if the vehicle speed V2 of the preceding vehicle 2 is extremely low, even if the preceding vehicle 2 makes a sudden steering maneuver to the right, the change in the behavior of the preceding vehicle 2 will be slow, and vehicle 1 can overtake the preceding vehicle 2 from the right with ample margin. On the other hand, if the vehicle speed V2 of the preceding vehicle 2 is extremely high, if the preceding vehicle 2 makes a sudden steering maneuver to the right, the behavior of the preceding vehicle 2 will also change suddenly, and there is a possibility that vehicle 1, which is trying to overtake the preceding vehicle 2 from the right, will come into contact with the preceding vehicle 2. Therefore, the determination unit 22 is configured to determine that the driving condition of the preceding vehicle 2 is abnormal when it determines that vehicle 1 can safely overtake the preceding vehicle 2.

[0039] (3) Combination of the position of the preceding vehicle and the speed difference of the preceding vehicle The determination unit 22 may determine whether the driving state of the preceding vehicle 2 is abnormal based on the combination of the position of the preceding vehicle 2 in the lane L1 and the speed difference ΔV between the preceding vehicle 2 and the surrounding traffic flow. FIG. 5 is an example of a map for determining the driving state of the preceding vehicle 2 based on the position of the preceding vehicle 2 and the speed difference ΔV of the preceding vehicle 2. The horizontal axis in FIG. 5 represents the distance X2 from the center line M0 of the lane L1 to the center line N2 of the preceding vehicle 2, and the vertical axis represents the speed difference ΔV between the vehicle speed V2 of the preceding vehicle 2 and the vehicle speeds of other vehicles. M0, M1, and M2 on the horizontal axis correspond to the center line, the left end, and the right end of the lane L1, respectively. Here, the vehicle speed of other vehicles is, for example, the vehicle speed V3 of the adjacent vehicle 3 or the vehicle speed V4 of the vehicle in front of the vehicle in front of the preceding vehicle 4.

[0040] In the map shown in FIG. 5, the area R1 surrounded by the broken line is a range representing an abnormal state determined based on the distance X2 from the center line M0 of the lane of the preceding vehicle 2 described in (1) above. When the distance X2 of the preceding vehicle 2 is within the area R1, it is determined that the driving state of the preceding vehicle 2 is an abnormal state (X2 ≤ -A1). In this case, the abnormal state of the preceding vehicle 2 may be determined in consideration of the fact that the vehicle 1 is traveling substantially along the center line M0 of the lane as described above (-A0 < X1 < A0).

[0041] In the map shown in FIG. 5, the area R2 surrounded by the dotted line is a range representing an abnormal state determined based on the speed difference ΔV between the preceding vehicle 2 and the surrounding traffic flow described in (2) above. When the speed difference ΔV between the vehicle speed V2 of the preceding vehicle 2 and the vehicle speed V3 of the adjacent vehicle 3, or the speed difference ΔV between the vehicle speed V2 of the preceding vehicle 2 and the vehicle speed V4 of the vehicle in front of the vehicle in front of the preceding vehicle 4 is within the area R2, it is determined that the driving state of the preceding vehicle 2 is an abnormal state (ΔV ≥ B1).

[0042] In the map shown in Figure 5, the region R3 enclosed by the dashed line represents an abnormal condition determined based on the distance X2 of the preceding vehicle 2 from the lane centerline M0 and the speed difference ΔV between the preceding vehicle 2 and the surrounding traffic flow. If the distance X2 of the preceding vehicle 2 from the lane centerline M0 is greater than or equal to a predetermined value A1, and the speed difference ΔV 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 smaller than the predetermined value B1 used to determine the region R2 described above (for example, B2 = approximately 30 km / h). In other words, the determination unit 22 determines that the driving condition of the preceding vehicle 2 is abnormal if the preceding vehicle 2 is traveling on the right side of lane L1 at a speed that is somewhat slower than the traffic flow.

[0043] If the preceding vehicle 2 is traveling on the right side of lane L1, in the direction of approaching the adjacent lane L2, then, as described above, there is a possibility that vehicle 1 may collide with the preceding vehicle 2 during overtaking. However, if the preceding vehicle 2 is traveling extremely close to the right edge of lane L1, it is possible that the driver of the preceding vehicle 2 is distracted or asleep and not concentrating on driving. Therefore, if the speed V2 of the preceding vehicle 2 is somewhat slower than the surrounding traffic flow, the system determines whether the driving condition of the preceding vehicle 2 is abnormal, taking into account the risk of following the preceding vehicle 2 which is exhibiting dangerous behavior and the risk of a side collision with the preceding vehicle 2 due to a sudden steering maneuver by the preceding vehicle 2 during overtaking. The determination unit 22 determines that if X2 ≥ A1 and ΔV ≥ B2, the preceding vehicle 2 is traveling extremely close to the right edge of lane L1, and that safe overtaking of the preceding vehicle 2 is possible, and therefore determines that the driving condition of the preceding vehicle 2 is abnormal.

[0044] The determination unit 22 determines that the driving condition of the preceding vehicle 2 is abnormal if the combination of distance X2 and speed difference ΔV falls within any of the regions R1 to R3 shown in Figure 5, based on the distance X2 from the center line M0 of lane L1 to the center line N2 of the preceding vehicle 2, and the speed difference ΔV between the speed V2 of the preceding vehicle 2 and the speed of other vehicles. In this way, the determination unit 22 also considers whether vehicle 1 can safely overtake the preceding vehicle 2 to determine whether the driving condition of the preceding vehicle 2 is abnormal.

[0045] The notification control unit 23 is configured to control the notification device 50 to display a notification prompting the driver to overtake the preceding vehicle 2 when the determination unit 22 determines that the driving condition of the preceding vehicle 2 is abnormal. The notification device 50 displays a notification prompting the driver to overtake the preceding vehicle 2 when the driving condition of the preceding vehicle 2 is abnormal and exhibiting dangerous behavior, in response to a command from the notification control unit 23. The notification prompting overtaking is expressed, for example, by text, illustrations, etc. The notification control unit 23 may also issue a notification prompting the driver to overtake the preceding vehicle 2 and to change the preceding vehicle that is the target of the follow-up driving. The notification control unit 23 may further notify that the driving condition of the preceding vehicle 2 is abnormal. When a driver sees the notification displayed on the notification device 50, they understand that the driving condition of the preceding vehicle 2 is abnormal and that overtaking is recommended, and they take driving actions themselves to overtake the preceding vehicle 2.

[0046] Below, the flow of notification control performed in this embodiment according to the driving state of the preceding vehicle 2 will be explained using the flowchart in Figure 6. Figure 6 shows an example of notification control processing, which is performed periodically by the control device 20 while follow-driving control by the ACC function is in operation.

[0047] In step S101, the control device 20 acquires information about the surrounding environment of the vehicle 1 detected by the imaging device 11 and the obstacle detection device 12.

[0048] In step S102, the determination unit 22 performs image processing on the image data of the 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 preceding vehicle 2 and the center line M0 of lane L1. Vehicle 1 is following preceding vehicle 2 by follow driving control, and preceding vehicle 2 is the vehicle being followed.

[0049] In step S103, the determination unit 22 calculates the speed difference ΔV between the vehicle speed V2 of the preceding vehicle 2 and the vehicle speeds of other vehicles existing around the preceding vehicle 2. As shown in FIG. 3, when there is an adjacent vehicle 3 in the adjacent lane L2, the determination 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. As shown in FIG. 4, when there is a preceding vehicle 4 in front of the preceding vehicle 2, the determination unit 22 calculates the speed difference ΔV (= V4 - V2) between the vehicle speed V4 of the preceding vehicle 4 and the vehicle speed V2 of the preceding vehicle 2. When both the adjacent vehicle 3 and the preceding vehicle 4 exist, the determination unit 22 may use the average value of the speed difference with the adjacent vehicle 3 and the speed difference with the preceding vehicle 4 as the speed difference ΔV with the vehicle speeds of other vehicles, or may use either one of the speed difference with the adjacent vehicle 3 and the speed difference with the preceding vehicle 4.

[0050] In step S104, the determination unit 22 determines whether the running state of the preceding vehicle 2 is within the region R1 of the map shown in FIG. 5. The determination unit 22 compares the distance X2 of the preceding vehicle 2 calculated in step S102 with a predetermined value A1, and compares the distance X1 of the vehicle 1 with a predetermined value A0. When the preceding vehicle 2 is shifted toward the left end of the lane L2 with respect to the center line M0 of the lane L1 (X2 ≦ -A1), and the vehicle 1 is traveling substantially along the center line M0 of the lane (-A0 < X1 < A0), the determination unit 22 determines that the running state of the preceding vehicle 2 is within the region R1. In this case, the preceding vehicle 2 is traveling extremely to the left of the lane L1, that is, on the side moving away from the adjacent lane L2, and it is determined that the running state is abnormal, and the process proceeds to step S107. On the other hand, if the determination in step S104 is negative, the process proceeds to step S105.

[0051] In step S105, the determination unit 22 determines whether the driving state of the preceding vehicle 2 is within the region R2 of the map shown in Figure 5. The determination unit 22 compares the speed difference ΔV between the preceding vehicle 2 and other vehicles, calculated in step S103, with a predetermined value B1. If the preceding vehicle 2 is traveling at an extremely slow speed compared to other surrounding vehicles (ΔV ≥ B1), the determination unit 22 determines that the driving state of the preceding vehicle 2 is within the region R2. In this case, the preceding vehicle 2 is traveling at an extremely slow speed relative to the traffic flow, and its driving state is determined to be abnormal, and the process proceeds to step S107. On the other hand, if the determination in step S105 is negative, the process proceeds to step S106.

[0052] In step S106, the determination unit 22 determines whether the driving state of the preceding vehicle 2 is within region R3 of the map shown in Figure 5. The determination unit 22 compares the distance X2 of the preceding vehicle 2 with a predetermined value A1, and compares the speed difference ΔV between the preceding vehicle 2 and other vehicles with a predetermined value B2. If the preceding vehicle 2 is deviated to the right edge of lane L2 relative to the center line M0 of lane L1 (X2≧A1), and the preceding vehicle 2 is traveling at a relatively slow speed relative to other surrounding vehicles (ΔV≧B2), the determination unit 22 determines that the driving state of the preceding vehicle 2 is within region R3. In this case, the preceding vehicle 2 is traveling extremely far to the right of lane L1, that is, on the side approaching the adjacent lane L2, at a slow speed relative to the traffic flow, and the driving state is determined to be abnormal, and the process proceeds to step S107. On the other hand, if the determination in step S106 is negative, this process ends.

[0053] In step S107, the notification control unit 23 controls the notification device 50 to display a notification prompting the driver to overtake the preceding vehicle 2, which the determination unit 22 has determined to be in an abnormal driving state. This completes the process shown in Figure 6.

[0054] The driver assistance system 10 according to this embodiment, as described above, can provide the following effects.

[0055] (1) The driving support system 10 includes an imaging device 11 and an obstacle detection device 12 that detect the surrounding environment of vehicle 1, including a preceding vehicle 2 that is in the lane L1 in which vehicle 1 is traveling; a determination unit 22 configured to determine whether the driving state of the preceding vehicle 2 is normal or not based on the information of the preceding vehicle 2 detected by the imaging device 11 and the obstacle detection device 12; and a notification control unit 23 configured to control a notification device 50 to issue a notification prompting the preceding vehicle 2 to overtake if the determination unit 22 determines that the driving state of the preceding vehicle 2 is abnormal.

[0056] If the preceding vehicle 2 is driving abnormally, vehicle 1, which is traveling behind vehicle 2, may be involved in a dangerous situation due to the unexpected driving actions of vehicle 2. Therefore, by issuing a notification prompting overtaking when it is determined that the preceding vehicle is driving abnormally, it is possible to make the driver of vehicle 1 aware of the abnormal driving condition of vehicle 2 and guide them to take appropriate driving actions.

[0057] (2) The determination unit 22 determines whether the driving condition of the preceding vehicle 2 is abnormal based on the distance X2 between the center line N2 of the preceding vehicle 2 in the longitudinal direction and the center line M0 of lane L1, and whether the preceding vehicle 2 can safely overtake. The notification control unit 23 controls the notification device 50 to issue a notification prompting the preceding vehicle 2 to overtake if it is determined that the distance X2 between the center line N2 of the preceding vehicle 2 and the center line M0 of lane L1 is greater than or equal to a predetermined value A1, and that the preceding vehicle 2 can safely overtake. If it is determined that vehicle 1 can safely overtake the preceding vehicle 2, the notification unit 23 determines that the driving condition of the preceding vehicle 2 is abnormal, and also considers whether vehicle 1 can safely overtake the preceding vehicle 2, and can issue a notification prompting the preceding vehicle 2 to overtake.

[0058] (3) The determination unit 22 determines that safe overtaking is possible for the preceding vehicle 2 if the center line N2 of the preceding vehicle 2 is on the side further away from the adjacent lane L2 that is adjacent to lane L1 than the center line M0 of lane L1. If the preceding vehicle 2 is on the side further away from the adjacent lane L2 than the center line M0 of lane L1 and the absolute value of the distance X2 is greater than or equal to a predetermined value A1, then even if the preceding vehicle 2 makes an unexpected steering maneuver toward the adjacent lane L2 while vehicle 1 is attempting to overtake the preceding vehicle 2 from the adjacent lane L2 side, it is considered unlikely that vehicle 1 will collide with the preceding vehicle 2. In this way, when it is determined that vehicle 1 can safely overtake the preceding vehicle 2, the determination unit 2 determines that the driving condition of the preceding vehicle 2 is abnormal, and by considering whether vehicle 1 can safely overtake the preceding vehicle 2, it is possible to issue a notification encouraging the preceding vehicle 2 to overtake.

[0059] (4) The determination unit 22 determines that the driving condition of the preceding vehicle 2 is abnormal if the vehicle speed V2 of the preceding vehicle 2 is lower than the vehicle speeds V3 and V4 of the other vehicles 3 and 4 present around the preceding vehicle 2, and the speed difference ΔV between the vehicle speed V2 of the preceding vehicle 2 and the vehicle speeds V3 and V4 of the other vehicles 3 and 4 is greater than or equal to a predetermined value B1. If the vehicle speed V2 of the preceding vehicle 2 is extremely slow compared to the surrounding traffic flow, it indicates that the driver of the preceding vehicle 2 is not concentrating on driving operations or is not performing normal driving operations. In such a state, by issuing a notification prompting the preceding vehicle 2 to overtake, it is possible to make the driver of vehicle 1 aware of the abnormal driving condition of the preceding vehicle 2 and guide them to appropriate driving operations.

[0060] (5) The driver assistance system 10 includes an ACC control unit (interval distance control unit) 21 configured to maintain a set distance and perform following driving when a preceding vehicle 2 is in the lane L1 in which the vehicle 1 is traveling. The determination unit 22 determines whether the driving condition of the preceding vehicle 2 is normal when following driving is being performed by the ACC control unit 21. While following driving is being performed by the ACC function, the vehicle 1 is driving behind the preceding vehicle 2 while maintaining a set distance, but if the preceding vehicle 2 is not driving normally, for example, there is a possibility of collision with the preceding vehicle 2 due to an unexpected deceleration by the preceding vehicle 2. Therefore, when it is determined that the driving condition of the preceding vehicle 2 is abnormal, a notification prompting overtaking is issued, making it possible to make the driver of the vehicle 1 aware of the abnormal driving condition of the preceding vehicle 2 and to guide them to appropriate driving operations.

[0061] -Second Embodiment- The following describes a driver assistance system 10 according to a second embodiment of the present invention. The basic configuration of the driver assistance system 10 according to the second embodiment is the same as that of the first embodiment described above. The following mainly describes the differences from the first embodiment.

[0062] In the first embodiment described above, the notification device 50 is configured to display a notification prompting the driver to overtake the preceding vehicle 2 if it is determined that the preceding vehicle 2 is in an abnormal condition. In the second embodiment, even if it is not determined that the preceding vehicle 2 is in an abnormal condition, the system is configured to support the driver's driving operations by providing appropriate information to the driver of vehicle 1. Specifically, if the preceding vehicle 2 is exhibiting dangerous behavior, but it is not possible for vehicle 1 to safely overtake the preceding vehicle 2, the system provides a notification to the driver of vehicle 1 prompting them to increase the distance between vehicle 1 and the preceding vehicle 2.

[0063] Figure 7 is an example of a map for determining the driving state of the preceding vehicle 2 based on the position of the preceding vehicle 2 and the speed difference ΔV of the preceding vehicle 2 in this embodiment. The map in Figure 7 further includes a region R4 enclosed by a dashed line, compared to the map in Figure 5 described in the first embodiment above. Region R4 represents a state in which the preceding vehicle 2 is exhibiting dangerous behavior, but it cannot be said that safe overtaking of the preceding vehicle 2 is possible. The determination unit 22 determines that if the distance X2 of the preceding vehicle 2 from the lane centerline M0 is greater than or equal to a predetermined value A1, and the speed difference ΔV between the preceding vehicle 2 and the surrounding traffic flow is less than a predetermined value B2, then the preceding vehicle 2 is exhibiting dangerous behavior, but it cannot be said that safe overtaking is possible (X2≧A1, and ΔV <B2)。

[0064] As described above, if the preceding vehicle 2 is traveling on the right side of lane L1, which is in the direction of approaching the adjacent lane L2, there is a possibility that vehicle 1 will collide with the preceding vehicle 2 during an overtake. Also, if the speed V2 of the preceding vehicle 2 is high, there is a high possibility that vehicle 1, which is attempting to overtake the preceding vehicle 2 from the right, will come into contact with the preceding vehicle 2 if the preceding vehicle 2 makes a sudden steering maneuver to the right. In such a situation, it cannot be said that vehicle 1 can safely overtake the preceding vehicle 2. In other words, the driving condition of the preceding vehicle 2 is high-risk for vehicle 1 to follow, but is not suitable for vehicle 1 to safely overtake the preceding vehicle 2. The determination unit 22 determines that if the driving condition of the preceding vehicle 2 is within the range of region R4, that is, if the preceding vehicle 2 is traveling at high speed on the right side of lane L1, the behavior of the preceding vehicle 2 is dangerous and unsuitable for a safe overtake.

[0065] If the determination unit 22 determines that the driving state of the preceding vehicle 2 is within the range of region R4, the notification control unit 23 controls the notification device 50 to issue a notification prompting the preceding vehicle 2 to increase the distance between them. The notification control unit 23 may also further notify if the preceding vehicle 2 is exhibiting dangerous behavior.

[0066] Upon seeing the display on the notification device 50, the driver understands that the preceding vehicle 2 is exhibiting dangerous behavior and takes driving actions to increase the distance between their vehicle and the preceding vehicle 2. Alternatively, while the ACC function is running, the driver assistance system 10 may, after the notification control unit 23 displays a notification prompting the driver to increase the distance between their vehicle and the preceding vehicle 2, automatically control the braking device 30 and the drive device 40 to increase the distance between their vehicle and the preceding vehicle 2 in response to a switch operation corresponding to the driver's intention to increase the distance. In this case, the driver assistance system 10 may, after the notification prompting the driver to increase the distance between their vehicle and the preceding vehicle 2 is displayed, automatically control the braking and driving force of vehicle 1 to increase the distance between their vehicle and the preceding vehicle 2, regardless of the driver's intention.

[0067] Below, the flow of notification control performed in this embodiment according to the driving state of the preceding vehicle 2 will be explained using the flowchart in Figure 8. Figure 8 is an example of the notification control process, which is performed periodically by the control device 20 while the follow-up driving control by the ACC function is in operation. In the flowchart of Figure 8, the processes from steps S101 to S107 are the same as those in the flowchart shown in Figure 6, so their explanation will be omitted.

[0068] If step S106 is deemed negative, that is, if the driving state of the preceding vehicle 2 does not fall under any of the regions R1 to R3 on the map shown in Figure 7, the process proceeds to step S111.

[0069] In step S111, the determination unit 22 determines whether the driving state of the preceding vehicle 2 is within the area R4 of the map shown in FIG. 7. The determination unit 22 compares the distance X2 of the preceding vehicle 2 with a predetermined value A1 and compares the speed difference ΔV between the preceding vehicle 2 and other vehicles with a predetermined value B2. When the preceding vehicle 2 is offset to the right end of the lane L2 with respect to the center line M0 of the lane L1 (X2≧A1), and the preceding vehicle 2 is traveling at a certain speed with respect to other surrounding vehicles (ΔV<B2), the determination unit 22 determines that the driving state of the preceding vehicle 2 is within the area R4. In this case, the preceding vehicle 2 is traveling at a high speed on the far right side of the lane L1, that is, on the side approaching the adjacent lane L2. The behavior of the preceding vehicle 2 is determined to be dangerous and unsuitable for safe overtaking, and the process proceeds to step S112. On the other hand, if the determination in step S111 is negative, this process ends.

[0070] In step S112, the notification control unit 23 controls the notification device 50 to display a notification prompting the driver to increase the inter-vehicle distance with respect to the preceding vehicle 2 determined by the determination unit 22 to be exhibiting a dangerous behavior. Thereby, the process shown in FIG. 8 ends.

[0071] In addition to the effects of the first embodiment described above, the driving support system 10 according to the present embodiment described above can exhibit the following effects.

[0072] When the distance X2 between the center line N2 of the preceding vehicle 2 and the center line M0 of the lane L1 is greater than or equal to a predetermined value A1 and it is determined that safe overtaking of the preceding vehicle 2 is not possible, the notification control unit 23 controls the notification device 50 to issue a notification prompting the driver to increase the inter-vehicle distance between the preceding vehicle 2 and the vehicle 1. When the preceding vehicle 2 is traveling while offset to the edge of the lane L1, the preceding vehicle 2 exhibits dangerous behavior. When it is determined that safe overtaking of the preceding vehicle 2 is not possible, by prompting the driver to increase the inter-vehicle distance from the preceding vehicle 2, the driver of the vehicle 1 can be made aware of the dangerous behavior of the preceding vehicle 2 and be guided to appropriate driving operations. Thereby, even when it is determined that safe overtaking of the preceding vehicle 2 is not possible, the driving operation of the driver can be supported.

[0073] -Third Embodiment- The following describes a third embodiment of the driver assistance system 10 of the present invention. The basic configuration of the third embodiment of the driver assistance system 10 is the same as that of the first and second embodiments described above. The following mainly describes the differences from the second embodiment.

[0074] In the second embodiment described above, the determination unit 22 determined the driving state of the preceding vehicle 2 using the map shown in Figure 7. In this embodiment, the determination unit 22 determines the driving state of the preceding vehicle 2 using a different map than the one shown in Figure 7. Figure 9 shows an example of a map for determining the driving state of the preceding vehicle 2 based on the position of the preceding vehicle 2 and the speed difference ΔV of the preceding vehicle 2. The map in Figure 9 is designed to determine the driving state based on the degree of abnormality of the preceding vehicle 2. For example, the greater the distance X2 of the preceding vehicle 2 from the center line M0 of lane L1, i.e., the closer the preceding vehicle 2 is to the edge of lane L1, and the greater the speed difference ΔV between the preceding vehicle 2 and the surrounding traffic flow, i.e., the slower the vehicle speed V2 of the preceding vehicle 2 is compared to the surrounding traffic flow, the higher the degree of abnormality of the preceding vehicle is defined.

[0075] In the map shown in Figure 9, the area R10 enclosed by the dotted line represents a range indicating a moderate degree of abnormality in the preceding vehicle 2. The determination unit 22 determines that the preceding vehicle 2 has a moderate degree of abnormality if the distance X2 from the lane centerline M0 of the preceding vehicle 2 and the speed difference ΔV between the preceding vehicle 2 and the surrounding traffic flow satisfy the following conditions. When the degree of abnormality is moderate, the driving state of the preceding vehicle 2 is defined as the first state. ·-C2 <X2≦-C1、かつ、ΔV<D1、 ·-C2 <X2<C2、かつ、D2≦ΔV<D1、または C1 ≤ X2 <C2、かつ、D3≦ΔV<D1

[0076] In the map shown in Figure 9, the area R20 enclosed by the dashed line represents a range indicating a high degree of abnormality in the preceding vehicle 2. The determination unit 22 determines that the preceding vehicle 2 is highly abnormal if the distance X2 from the lane centerline M0 of the preceding vehicle 2 and the speed difference ΔV between the preceding vehicle 2 and the surrounding traffic flow satisfy the following conditions. When the degree of abnormality is high, the driving state of the preceding vehicle 2 is defined as the second state. -C2≧X2, · D1 ≤ ΔV, or C2 ≤ X2 and D3 ≤ ΔV

[0077] Here, a predetermined value D1 of the speed difference ΔV is a threshold for determining that the degree of abnormality of the preceding vehicle 2 is high, and is set to, for example, approximately 40 to approximately 45 km / h. A predetermined value D2 of the speed difference ΔV is a threshold for determining that the degree of abnormality of the preceding vehicle 2 is moderate, and is set to, for example, approximately 30 to approximately 35 km / h. A predetermined value D3 of the speed difference ΔV is a threshold for determining that the degree of abnormality of the preceding vehicle 2 is moderate or high, in combination with the distance X2 of the preceding vehicle 2, and is set to, for example, approximately 25 km / h. In addition, a predetermined value C1 of the distance X2 of the preceding vehicle 2 is a threshold for determining that the degree of abnormality of the preceding vehicle 2 is moderate, and a predetermined value C2 of the distance X2 of the preceding vehicle 2 is a threshold for determining that the degree of abnormality of the preceding vehicle 2 is high. The predetermined values ​​C1 and C2 may be the same as in the first embodiment described above, or different values ​​may be used.

[0078] If the determination unit 22 determines that the driving state of the preceding vehicle 2 falls within region R10 and the degree of abnormality is moderate, the notification control unit 23 controls the notification device 50 to display a notification prompting the driver to increase the following distance. On the other hand, if the determination unit 22 determines that the driving state of the preceding vehicle 2 falls within region R10 and the degree of abnormality is high, the notification control unit 23 controls the notification device 50 to display a notification prompting the driver to overtake the preceding vehicle 2.

[0079] The determination unit 22 may determine the driving state of the preceding vehicle 2 based on the following conditions instead of the map shown in Figure 9. (i) The determination unit 22 determines that the degree of abnormality of the preceding vehicle 2 is within the first range if the distance X2 of the preceding vehicle 2 from the lane centerline M0 is less than or equal to the first distance threshold (-C1) (if the absolute value of the distance X2 is greater than or equal to the first distance threshold (C1)), or if the vehicle speed V2 of the preceding vehicle 2 is less than the vehicle speeds of the other vehicles 3 and 4, and the speed difference ΔV is greater than or equal to the first speed difference threshold (ΔD2). The first range roughly corresponds to region R10 on the map in Figure 9 and represents a range where the degree of abnormality is moderate. If the degree of abnormality is within the first range, the driving state of the preceding vehicle 2 is defined as the first state. (ii) The determination unit 22 determines that the degree of abnormality of the preceding vehicle 2 is within the second range if the distance X2 of the preceding vehicle 2 from the lane centerline M0 is less than or equal to the second distance threshold (-C2) (i.e., 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 preceding vehicle 2 is less than the vehicle speeds of the other vehicles 3 and 4, and the speed difference ΔV is greater than or equal to the second speed difference threshold (D1), which is greater than the first speed difference threshold (D2). The second range roughly corresponds to region R20 on the map in Figure 9 and represents a range where the degree of abnormality is high. If the degree of abnormality is within the second range, the driving state of the preceding vehicle 2 is defined as the second state.

[0080] In addition to the effects and advantages of the first and second embodiments described above, the driver assistance system 10 according to this embodiment can provide the following effects and advantages.

[0081] (1) The determination unit 22 calculates the degree of abnormality of the driving state of the preceding vehicle 2 based on the information of the preceding vehicle 2 detected by the imaging device 11 and the obstacle detection device 12. The determination unit 22 determines that the driving state of the preceding vehicle 2 is in the first state if the calculated degree of abnormality is within the first range (region R10) which indicates a moderate degree, and determines that the driving state of the preceding vehicle 2 is in the second state if the calculated degree of abnormality is within the second range (region R20) which indicates a high degree of abnormality. The notification control unit 23 controls the notification device 50 to issue a notification prompting the preceding vehicle 2 to overtake if the driving state of the preceding vehicle 2 is in the second state, and controls the notification device 50 to issue a notification prompting the driver to increase the distance between the preceding vehicle 2 and vehicle 1 if the driving state of the preceding vehicle 2 is in the first state. This allows the driver to receive appropriate notifications according to the degree of abnormality of the preceding vehicle 2, and to appropriately support the driver's driving operations. The driving maneuvers required to overtake vehicle 2 involve a combination of acceleration / deceleration and steering of vehicle 1, which some drivers may find difficult. By limiting the notification prompting overtaking vehicle 2 to only cases where vehicle 2 exhibits a high degree of abnormality, overtaking can be prompted only in situations where it is deemed necessary to avoid the dangerous vehicle 2.

[0082] (2) The determination unit 22 calculates the degree of abnormality of the driving condition of the preceding vehicle 2 based on the distance X2 between the center line N2 in the longitudinal direction of the preceding vehicle 2 and the center line M0 of the lane L1, and the speed difference ΔV between the speed V2 of the preceding vehicle 2 and the speeds V3 and V4 of the other vehicles 3 and 4 present around the preceding vehicle 2. The determination unit 22 determines that the degree of abnormality is within the first range (region R10) if the distance X2 is less than or equal to the first distance threshold (-C1), or if the speed V2 of the preceding vehicle 2 is less than the speeds V3 and V4 of the other vehicles 3 and 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 abnormality is within the second range (region R20) if the distance X2 is less than or equal to the second distance threshold (-C2), which is smaller than the first distance threshold (-C1), or if the vehicle speed V2 of the preceding vehicle 2 is smaller than the vehicle speeds V3 and V4 of the other vehicles 3 and 4, and the speed difference ΔV is greater than or equal to the second speed difference threshold (ΔD1), which is larger than the first speed difference threshold (ΔD2). As a result, the closer the preceding vehicle 2 is to the edge of lane L1, and the slower the vehicle speed V2 of the preceding vehicle 2 is compared to the surrounding traffic flow, the higher the degree of abnormality of the preceding vehicle is determined to be, and the system can encourage the preceding vehicle 2 to overtake in situations where it is considered necessary to avoid the dangerous preceding vehicle 2.

[0083] -Variations- (1) In the above-described embodiment, an example was described in which the driver assistance system 10 displays a notification prompting the driver to overtake the preceding vehicle 2, or a notification prompting the driver to increase the distance between vehicles, while the ACC function is operating for follow-up driving control. However, the present invention is not limited to this, and can be applied even when the driver assistance system 10 is not performing follow-up driving control using the ACC function. For example, when the driver of vehicle 1 is driving in a way that follows the preceding vehicle 2 by manual driving operations, if the determination unit 22 determines that the driving condition of the preceding vehicle 2 is abnormal, the notification device 50 may display a notification prompting the driver to overtake the preceding vehicle 2. Furthermore, the present invention can be applied even when the driver assistance system 10 does not have an ACC function.

[0084] (2) In the embodiment described above, the determination unit 22 determined whether the driving condition of the preceding vehicle 2 was abnormal based on the speed difference ΔV between the preceding vehicle 2 and the surrounding traffic flow. However, it is not limited to this, and the driving condition may be determined using the vehicle speed V2 of the preceding vehicle 2 instead of the speed difference ΔV. For example, the determination unit 22 may determine that the driving condition of the preceding vehicle 2 is abnormal if the preceding vehicle 2 is driving at an extremely low speed of a predetermined value (for example, about 10 to about 20 km / h) or less and is extremely close to the edge of lane L1. When the vehicle speed V2 of the preceding vehicle 2 is very low, even if the preceding vehicle 2 performs an unexpected steering operation, the change in the behavior of the preceding vehicle 2 will be gradual. Therefore, the determination unit 22 can determine that it is possible for the preceding vehicle 2 to safely overtake. In other words, the determination unit 22 may determine that it is possible for the preceding vehicle 2 to safely overtake if the vehicle speed V2 of the preceding vehicle 2 is at an extremely (abnormal) low speed of a predetermined value or less.

[0085] (3) In the above-described embodiment, the driver was provided with a notification prompting him to overtake the preceding vehicle 2 and a notification prompting him to increase the distance between vehicles by displaying them on the notification device 50. However, the present invention is not limited thereto, and in addition to or instead of display notifications, the driver may be provided with a notification prompting him to overtake the preceding vehicle 2 and a notification prompting him to increase the distance between vehicles by voice.

[0086] (4) The determination unit 22 may determine whether the preceding vehicle 2 is driving close to the edge of lane L1 based on the distance from the lane markings M1 and M2 of lane L1, instead of the distance from the lane center line M0.

[0087] Although several embodiments of the present invention have been described above, it should be noted that the present invention is not limited to the above embodiments, and various further modifications and changes are possible within the scope of the present invention. [Explanation of symbols]

[0088] 1 vehicle 2. Leading vehicle 3. Adjacent vehicles 4. The train ahead 10. Driver assistance systems 11. Imaging device (surrounding environment detection device) 12. Obstacle detection device (surrounding environment detection device) 20 Control device 21 ACC Control Unit (Adaptive Cruise Control Unit) 22 Judgment section 23 Notification Control Unit

Claims

1. An ambient environment detection device that detects the surrounding environment of the vehicle, including a preceding vehicle located within the lane in which the vehicle is traveling, A determination unit configured to determine whether the driving state of the preceding vehicle is normal or not based on the information of the preceding vehicle detected by the surrounding environment detection device, When the determination unit determines that the driving condition of the preceding vehicle is abnormal, the notification control unit is configured to control the notification device to issue a notification prompting the preceding vehicle to overtake. A driver assistance system equipped with these features.

2. The determination unit determines whether the driving condition of the preceding vehicle is abnormal based on the distance between the center line of the preceding vehicle in the longitudinal direction and the center line of the lane, and whether or not it is possible to safely overtake the preceding vehicle. The driver assistance system according to claim 1, wherein the notification control unit controls the notification device to issue a notification prompting the driver to overtake the preceding vehicle when it is determined that the distance between the center line of the preceding vehicle and the center line of the lane is greater than or equal to a predetermined value and that safe overtaking of the preceding vehicle is possible.

3. The driver assistance system according to claim 2, wherein the determination unit determines that safe overtaking of the preceding vehicle is possible when the center line of the preceding vehicle is further away from the adjacent lane than the center line of the lane.

4. The driver assistance system according to claim 2, wherein the notification control unit controls the notification device to issue a notification prompting the driver to increase the distance between the preceding vehicle and the vehicle when it is determined that the distance between the center line of the preceding vehicle and the center line of the lane is greater than or equal to a predetermined value and that safe overtaking of the preceding vehicle is not possible.

5. The driver assistance system according to any one of claims 2 to 4, wherein the determination unit determines that safe overtaking of the preceding vehicle is possible when the vehicle speed of the preceding vehicle is at an extremely low speed below a predetermined value.

6. The driving assistance system according to claim 1, wherein the determination unit determines that the driving condition of the preceding vehicle is abnormal when the speed of the preceding vehicle is lower than the speeds of other vehicles present around the preceding vehicle, and the speed difference between the speed of the preceding vehicle and the speeds of the other vehicles is greater than or equal to a predetermined value.

7. The determination unit calculates the degree of abnormality in the driving state of the preceding vehicle based on the information of the preceding vehicle detected by the surrounding environment detection device. The determination unit determines that the driving state of the preceding vehicle is in a first state if the calculated degree of abnormality is within a first range indicating a moderate degree, and determines that the driving state of the preceding vehicle is in a second state if the calculated degree of abnormality is within a second range indicating a high degree. The driver assistance system according to claim 1, wherein the notification control unit controls the notification device to provide a notification encouraging the preceding vehicle to overtake when the preceding vehicle is in the second state, and controls the notification device to provide a notification encouraging the preceding vehicle to increase the distance between the preceding vehicle and the vehicle when the preceding vehicle is in the first state.

8. The determination unit calculates the degree of abnormality in the driving state of the preceding vehicle based on the distance between the center line of the preceding vehicle in the longitudinal direction and the center line of the lane, and the speed difference between the speed of the preceding vehicle and the speed of other vehicles present around the preceding vehicle. The determination unit, If the aforementioned distance is greater than or equal to the first distance threshold, or if the vehicle speed of the preceding vehicle is less than the vehicle speed of the other vehicle and the speed difference is greater than or equal to the first speed difference threshold, it is determined that the degree of abnormality is within the first range. The driving assistance system according to claim 7, which determines that the degree of abnormality is within the second range if the distance is greater than or equal to a second distance threshold greater than the first distance threshold, or if the vehicle speed of the preceding vehicle is less than the vehicle speed of the other vehicle and the speed difference is greater than or equal to a second speed difference threshold greater than the first speed difference threshold.

9. The vehicle further comprises a distance control unit configured to maintain a set distance and follow the preceding vehicle if the preceding vehicle is in the lane in which the vehicle is traveling, The driver assistance system according to claim 1, wherein the determination unit determines whether the driving state of the preceding vehicle is normal when the following driving is being performed by the following driving control unit.

Images