Driving assistance devices

Abstract

To provide a driving support device which can perform driving support including notification to a crew member of a vehicle according to a cause of fluctuation quantity of another vehicle.SOLUTION: A driving support device 100 performs driving support including notification to a crew member of a vehicle. The driving support device 100 comprises: a fluctuation quantity recognition unit 12 which recognizes a fluctuation quantity of another vehicle traveling around the vehicle on the basis of a detection result of an external sensor 1 provided in the vehicle; a driver abnormality recognition unit 13 which recognizes an abnormality of a driver of the other vehicle on the basis of a pickup image of an external camera 2 provided in the vehicle; an abnormal state determination unit 14 which determines whether or not the other vehicle is in a fluctuation abnormal state on the basis of a comparison result between the fluctuation quantity of the other vehicle and a fluctuation threshold; and a notification control unit 15 which performs notification regarding the fluctuation abnormal state. The abnormal state determination unit 14 determines whether or not the other vehicle is in the fluctuation abnormal state by using the fluctuation threshold when the abnormality of the driver of the other vehicle is recognized as an absolute value smaller than that of a fluctuation threshold when the abnormality of the driver of other vehicle is not recognized.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a driving assistance device. [Background technology]

[0002] Conventionally, there is known a driving assistance device that calculates driving performance based on the behavior of a vehicle behind and the driver's condition obtained using a monitoring means that monitors the rear of the vehicle, and notifies the driver of the vehicle according to the driving performance (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-293531 Summary of the Invention [Problem to be solved by the invention]

[0004] The amount of fluctuation of another vehicle recognized based on the detection results of an external sensor provided in the vehicle may include an amount of fluctuation caused by an abnormality of the driver of the other vehicle, as well as an amount of fluctuation caused by the external environment, such as wind or road conditions, etc. Therefore, it is desirable to provide driving assistance, including a notification to the vehicle occupants, according to the cause of the amount of fluctuation of the other vehicle. [Means for solving the problem]

[0005] A driving assistance device according to one aspect of the present invention is a driving assistance device that provides driving assistance including notifying vehicle occupants, and is equipped with a fluctuation amount recognition unit that recognizes the amount of fluctuation of other vehicles traveling around the vehicle based on the detection results of an external sensor installed on the vehicle, a driver abnormality recognition unit that recognizes abnormalities in the drivers of the other vehicles based on images captured by an external camera installed on the vehicle, an abnormality state determination unit that determines whether the other vehicle is in an abnormal fluctuation state based on the results of comparing the fluctuation amount of the other vehicle with a fluctuation threshold, and a notification control unit that issues a notification regarding the abnormal fluctuation state, and the abnormality state determination unit determines whether or not an abnormal fluctuation state exists by setting the fluctuation threshold when an abnormality in the driver of the other vehicle is recognized as an absolute value that is smaller than the fluctuation threshold when an abnormality in the driver of the other vehicle is not recognized.

[0006] In a driving assistance device according to one aspect of the present invention, a fluctuation threshold when an abnormality in the driver of the other vehicle is recognized is set to a smaller absolute value than a fluctuation threshold when an abnormality in the driver of the other vehicle is not recognized, and whether or not an abnormal fluctuation state exists is determined. As a result, even if the amount of fluctuation is similar in a case where an abnormality in the driver of the other vehicle is not recognized and the other vehicle is swaying due to external conditions such as wind or road conditions, it is more likely to be determined that an abnormal fluctuation state exists in a case where an abnormality in the driver of the other vehicle is recognized. Therefore, the driving assistance device according to one aspect of the present invention can provide driving assistance, including notifying the vehicle occupants, depending on the cause of the amount of fluctuation in the other vehicle.

[0007] In one embodiment, the fluctuation amount recognition unit may recognize the road surface conditions of the road on which the vehicle and other vehicles are traveling based on the image captured by the external camera, and correct the fluctuation amount of the other vehicle based on the road surface conditions. In this case, by using the fluctuation amount corrected based on the road surface conditions, it is possible to more appropriately determine whether the other vehicle is in an abnormal fluctuation state depending on the road surface conditions. [Effects of the Invention]

[0008] According to the present invention, driving assistance including notification to vehicle occupants can be appropriately performed depending on the cause of the fluctuation amount of another vehicle. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a block diagram showing a configuration of a driving assistance device according to an embodiment. [Figure 2] FIG. 2 is a plan view illustrating an example of the relationship between the host vehicle and other vehicles. [Figure 3] FIG. 10 is a diagram illustrating an example of a fluctuation threshold when an abnormality in the driver of another vehicle is not recognized. [Figure 4] 10 is a diagram illustrating an example of a fluctuation threshold when an abnormality in a driver of another vehicle is recognized. FIG. [Figure 5] 2 is a flowchart showing an example of processing performed by the driving assistance device of FIG. 1. [Figure 6] 10 is a diagram illustrating an example of a fluctuation threshold corrected according to road surface conditions when an abnormality in the driver of another vehicle is recognized. FIG. [Figure 7] 10 is a flowchart showing a process of a driving assistance device according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same or equivalent elements will be designated by the same reference numerals, and redundant description will be omitted.

[0011] FIG. 1 is a block diagram showing the configuration of a driving assistance device according to an embodiment. The driving assistance device 100 shown in FIG. 1 is mounted on a vehicle such as a passenger car, and controls the vehicle based on the detection results of various on-board sensors. The vehicle control includes driving assistance control and HMI control such as notification to the driver (occupant). The vehicle control may also include automatic driving control. Automatic driving control is vehicle control that causes the vehicle to automatically travel along a target route. In automatic driving control, the vehicle travels automatically without the driver having to perform any driving operation. Driving assistance control is vehicle control that supports the driver in driving the vehicle. HMI control such as notification to the driver will be described later.

[0012] [Configuration of driving assistance device] As shown in Fig. 1, the driving assistance device 100 includes an ECU (Electronic Control Unit) 10 that performs overall system management. The ECU 10 is an electronic control unit that includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a CAN (Controller Area Network) communication circuit, and the like. The ECU 10, for example, loads programs stored in the ROM into the RAM and executes the programs loaded into the RAM with the CPU, thereby realizing various functions. The ECU 10 may be composed of multiple electronic units.

[0013] The ECU 10 is connected to an external sensor 1, an internal sensor 3, a map database 4, an actuator 6, and an HMI (Human Machine Interface) 6.

[0014] The external sensor 1 is a detection device that detects the situation around the vehicle (vehicle). The external sensor 1 includes an external camera 2. The external sensor 1 may include a radar sensor.

[0015] The external camera 2 is an imaging device that captures images of the external situation of the host vehicle. The external camera 2 includes a front camera 2a and a rear camera 2b. The front camera 2a is provided behind the windshield of the host vehicle. The rear camera 2b is provided behind the rear windshield of the host vehicle. The rear camera 2b is, for example, a camera for an electronic inner mirror, and has higher image quality than a rearview camera used for parking. The external camera 2 may include a camera that captures images of the external situation to the side of the host vehicle. The external camera 2 transmits imaging information related to the external situation of the host vehicle to the ECU 10. The external camera 2 may be a monocular camera or a stereo camera. The stereo camera has two imaging units arranged to reproduce binocular parallax. The imaging information of the stereo camera also includes information in the depth direction.

[0016] A radar sensor is a detection device that uses radio waves (e.g., millimeter waves) or light to detect objects around the vehicle. Radar sensors include, for example, millimeter wave radar or LIDAR (Light Detection and Ranging). A radar sensor detects objects by transmitting radio waves or light to the vicinity of the vehicle and receiving the radio waves or light reflected by the objects. The radar sensor transmits information about the detected objects to the ECU 10. Objects include fixed obstacles such as guardrails and buildings, as well as moving obstacles such as pedestrians, bicycles, and other vehicles.

[0017] The internal sensor 3 is a detection device for detecting the vehicle state of the host vehicle. The internal sensor 3 includes a vehicle speed sensor, an acceleration sensor, and a yaw rate sensor. The vehicle speed sensor is a detector that detects the speed of the host vehicle. The vehicle speed sensor transmits detected vehicle speed information (wheel speed information) to the ECU 10. The acceleration sensor is a detector that detects the acceleration of the host vehicle. The acceleration sensor transmits acceleration information of the host vehicle to the ECU 10. The yaw rate sensor is a detector that detects the yaw rate (rotational angular velocity) around the vertical axis of the center of gravity of the host vehicle. A gyro sensor, for example, can be used as the yaw rate sensor. The yaw rate sensor transmits detected yaw rate information of the host vehicle to the ECU 10.

[0018] The map database 4 is a database that stores map information. The map database 4 is formed, for example, in an HDD (Hard Disk Drive) mounted on the vehicle. The map information includes road position information, road shape information (e.g., curves, types of straight sections, curvature of curves, etc.), intersection and branch point position information, and structure position information. The map information may also include, for example, information on locations where a vehicle traveling on the road is likely to be shaken by crosswinds, uneven road surfaces, etc. The map database 4 may be provided in a management center that can communicate with the vehicle.

[0019] The communication unit 5 is a communication device that controls wireless communication with the outside of the vehicle. The communication unit 5, for example, communicates various types of information with a server via a communication network. The communication unit 5 may also perform vehicle-to-vehicle communication. The communication unit 5 is not particularly limited, and various known communication devices can be used.

[0020] The actuators 6 are devices used to control the host vehicle. The actuators 6 include at least a drive actuator, a brake actuator, and a steering actuator. The drive actuator controls the engine, motor, etc. in response to a control signal from the ECU 10, thereby controlling the drive force of the host vehicle. The brake actuator controls a brake system in response to a control signal from the ECU 10, thereby controlling the braking force applied to the wheels of the host vehicle. For example, a hydraulic brake system can be used as the brake system. The steering actuator controls the drive of an assist motor, which controls the steering torque of the electric power steering system, in response to a control signal from the ECU 10. In this way, the steering actuator controls the steering torque of the host vehicle.

[0021] The HMI 7 is an interface for inputting and outputting information between the driving assistance device 100 and the driver of the vehicle. The HMI 7 may include, for example, a display provided in a position visible to the driver and a speaker provided on the interior side of the door of the vehicle. The HMI 7 outputs images from the display and sounds from the speaker in response to a control signal from the ECU 10. The display may be a HUD (Head Up Display) that projects information onto the windshield of the vehicle. The display may be a device that outputs a light source such as an MID (Multi Information Display) or an LED. The display may also be a means for providing a bodily stimulus to the driver of the vehicle by vibrating the steering wheel, pedals, seat, etc.

[0022] Next, a description will be given of the functional configuration of the ECU 10. The ECU 10 has an external environment recognition unit 11, a fluctuation amount recognition unit 12, a driver abnormality recognition unit 13, an abnormal state determination unit 14, a notification control unit 15, and a vehicle control unit 16. Some of the functions of the ECU 10 described below may be executed by a server in a facility such as a management center that can communicate with the vehicle.

[0023] The external environment recognition unit 11 recognizes the external environment of the host vehicle based on the detection results of the external sensor 1 and the external camera 2. The external environment includes road surface conditions, the positions of other vehicles relative to the host vehicle, the relative speeds of other vehicles relative to the host vehicle, and the moving directions of other vehicles relative to the host vehicle. The external environment recognition unit 11 recognizes the external environment of the host vehicle using a well-known method based on object information from the radar sensor and images captured by the external camera 2, etc.

[0024] The fluctuation amount recognition unit 12 recognizes the fluctuation amount of other vehicles traveling around the host vehicle based on the detection results of the external sensor 1 provided on the host vehicle. The fluctuation amount of other vehicles indicates the magnitude of the behavior of the other vehicles and is used to determine whether or not there is an abnormality in the other vehicles. The fluctuation amount of other vehicles may be the width of fluctuation in the vehicle width direction when the other vehicles meanders in the vehicle width direction. For example, the width of fluctuation of the other vehicles in the image captured by the rear camera 2b may be the longitudinal acceleration of the other vehicles when the other vehicles suddenly accelerate in the traveling direction.

[0025] FIG. 2 is a plan view illustrating an example of the relationship between the host vehicle and another vehicle. In FIG. 2, as an example, a situation is assumed in which the host vehicle 20 and the other vehicle 30 are traveling in the same lane of a road 50. As shown in FIG. 2, the other vehicle 30 is captured by the rear camera 2b of the host vehicle 20. The captured image of the rear camera 2b shows the other vehicle 30 from a frontal view. The fluctuation amount recognition unit 12 recognizes the amount of fluctuation when the other vehicle 30 meanders in the vehicle width direction, for example, by using the amount of movement of the other vehicle 30 in the vehicle width direction in the time-series data of the captured image of the rear camera 2b as a fluctuation width. The fluctuation amount recognition unit 12 may recognize the longitudinal acceleration of the other vehicle when the other vehicle suddenly accelerates in the traveling direction, for example, based on object information detected by a radar sensor and the detection result of the internal sensor 3 of the host vehicle 20.

[0026] The fluctuation amount recognition unit 12 may recognize ruts (road surface conditions) 51 ahead of the host vehicle 20 based on an image captured by the external camera 2 of the host vehicle 20, and correct the fluctuation amount of the other vehicle 30 based on the ruts 51. For example, as shown in FIG. 2 , the front camera 2a of the host vehicle 20 captures an image of the ruts 51 ahead of the host vehicle 20. When the tires of the host vehicle 20 and the other vehicle 30 are caught in the ruts 51, the host vehicle 20 moves in the vehicle width direction by a certain amount of fluctuation due to the ruts 51, and the following other vehicle 30 also moves in the vehicle width direction by a certain amount of fluctuation due to the ruts 51. In this case, if the influence of the movement of the host vehicle 20 in the vehicle width direction is in phase with the fluctuation amount of the other vehicle 30, the fluctuation amount of the other vehicle 30 as seen from the host vehicle 20 may appear smaller.

[0027] Therefore, when the fluctuation amount recognition unit 12 recognizes a rut (road surface condition) 51 ahead of the host vehicle 20 based on an image captured by the front camera 2a of the host vehicle 20, the fluctuation amount recognition unit 12 may correct the fluctuation amount of the other vehicle 30 based on the rut 51. For example, the fluctuation amount recognition unit 12 may add a predetermined correction amount to the fluctuation amount of the other vehicle 30 while the host vehicle 20 is traveling on the recognized rut 51. The predetermined correction amount is a correction value for the fluctuation amount of the other vehicle 30 that prevents the behavior of the host vehicle 20 from making it difficult to recognize an abnormality in the other vehicle 30. The predetermined correction amount can be set to an average fluctuation amount of the behavior of the host vehicle 20 so that it becomes easier to recognize an abnormality in the other vehicle 30.

[0028] Similar to the example of the ruts 51, the fluctuation amount recognition unit 12 may correct the fluctuation amount of the other vehicle 30 when the fluctuation amount of the host vehicle 20 exceeds a certain level, or when the wind speed in the weather information received by the communication unit 5 exceeds a certain level. The fluctuation amount of the host vehicle 20 may be recognized based on the image captured by the external camera 2.

[0029] The driver abnormality recognition unit 13 recognizes an abnormality in the driver 31 of the other vehicle 30 based on an image captured by the external camera 2 provided on the host vehicle 20. The driver abnormality recognition unit 13 recognizes an abnormality in the driver 31 of the other vehicle 30 based on, for example, the position of the head of the driver 31 of the other vehicle 30 in an image captured by the rear camera 2b provided on the host vehicle 20. As shown in FIG. 2 , the rear camera 2b of the host vehicle 20 captures an image of the driver 31 of the other vehicle 30. When the driver 31 is driving the other vehicle 30 normally, the head of the driver 31 is located within a certain range including the driver's seat, which is visible through the windshield of the other vehicle 30 in a front view of the other vehicle 30. Therefore, when the head of the driver 31 is not located within the certain range, for example, because the upper body of the driver 31 is leaning forward, it can be estimated that there is an abnormality in the driver 31 of the other vehicle 30.

[0030] For example, if the rear camera 2b has a higher resolution than a camera for an electronic inner mirror and is able to recognize the gaze information of the driver 31 of the other vehicle 30, the driver abnormality recognition unit 13 may recognize an abnormality in the driver 31 of the other vehicle 30 based on the gaze direction of the driver 31 of the other vehicle 30 in the image captured by the rear camera 2b. The gaze information of the driver 31 of the other vehicle 30 may be recognized using a method similar to gaze recognition using a driver monitor camera in the host vehicle 20, for example.

[0031] The driver abnormality recognition unit 13 may recognize an abnormality in the driver 31 of the other vehicle 30 based on information about the other vehicle 30 acquired via the communication unit 5 in addition to the image captured by the external camera 2. The communication unit 5 receives a signal including the driver information of the other vehicle 30 from the other vehicle 30 via vehicle-to-vehicle communication. The driver information of the other vehicle 30 may include information such as the posture and line of sight of the driver 31 based on an image captured by a driver monitor camera of the other vehicle 30, the steering grip force of the driver 31, time series data of the steering operation of the driver 31, and time series data of the pedal operation of the driver 31.

[0032] The abnormal state determination unit 14 determines whether the other vehicle 30 is in an abnormal sway state based on the comparison result between the amount of sway of the other vehicle 30 and the sway threshold. The abnormal sway state is a state in which the other vehicle 30 is driving abnormally, accompanied by a certain level of sway or sudden acceleration. The sway threshold is a threshold value of the amount of sway of the other vehicle 30 for determining whether the other vehicle 30 is in an abnormal sway state. For example, if the amount of sway of the other vehicle 30 is greater than the sway threshold, the abnormal state determination unit 14 determines that the other vehicle 30 is in an abnormal sway state. For example, if the amount of sway of the other vehicle 30 is equal to or less than the sway threshold, the abnormal state determination unit 14 determines that the other vehicle 30 is not in an abnormal sway state.

[0033] The abnormal fluctuation state is mainly caused by an abnormality of the driver 31 of the other vehicle 30, but can also be caused by external environmental factors such as wind or road conditions. Therefore, the abnormal state determination unit 14 determines whether or not the other vehicle 30 is in an abnormal fluctuation state depending on the cause by changing the fluctuation threshold value according to the cause of the amount of fluctuation of the other vehicle 30.

[0034] FIG. 3 is a diagram illustrating a fluctuation threshold when no abnormality in the driver of another vehicle is recognized. In FIG. 3, the horizontal axis represents time, and the vertical axis represents the fluctuation amount of the other vehicle. FIG. 3 shows multiple schematic examples of fluctuation amounts. The depiction of the fluctuation amount in FIG. 3 is an example for simplifying the explanation. For example, as a result of depicting the maximum value of the fluctuation amount recognized during a predetermined time period, the fluctuation amount increases from the origin and becomes constant at a certain value. The explanation in this paragraph also applies to FIGS. 4 and 6.

[0035] 3, the fluctuation amount FL0 is the fluctuation amount of the other vehicle 30 when the other vehicle 30 is driving normally without swaying or sudden acceleration above a certain level. The fluctuation amount FL1 is the fluctuation amount of the other vehicle 30 when the other vehicle 30 is driving abnormally with swaying or sudden acceleration above a certain level. The fluctuation amount FL9 is the fluctuation amount of the other vehicle 30 when the driver 31 of the other vehicle 30 is normal and the other vehicle 30 is driving normally without swaying or sudden acceleration above a certain level, but is swaying due to external factors such as wind or road conditions.

[0036] In a state in which the other vehicle 30 is swaying only due to external factors such as wind or road conditions, if an abnormal swaying state is determined, the notification control unit 15 (described later) may issue a notification unnecessary for the occupants of the host vehicle 20. Therefore, the fluctuation threshold Th1 is set to be larger than the amount of fluctuation of the other vehicle 30 in a state in which the driver 31 of the other vehicle 30 is not abnormal and the other vehicle 30 is traveling normally without swaying or sudden acceleration beyond a certain level, but is swaying due to external factors such as wind or road conditions. The fluctuation threshold Th1 is a preset value, and is switched to another threshold (described later) by the abnormal state determination unit 14 depending on whether an abnormality in the driver 31 of the other vehicle 30 is recognized. As a result, the abnormal state determination unit 14 determines that the other vehicle 30 is in an abnormal swaying state when the fluctuation amount FL1 is larger than the fluctuation threshold Th1. The abnormal state determination unit 14 determines that the other vehicle 30 is not in an abnormal fluctuation state for the fluctuation amounts FL9 and FL0 that are equal to or less than the fluctuation threshold value Th1.

[0037] FIG. 4 is a diagram illustrating fluctuation thresholds when an abnormality in the driver of another vehicle is recognized. In FIG. 4, fluctuation amounts FL0 and FL1 are the same as those shown in FIG. 3. Fluctuation amount FL2 is the fluctuation amount of another vehicle 30 when the other vehicle 30 is traveling without swaying or sudden acceleration of a certain level or more, but the driver 31 of the other vehicle 30 is experiencing an abnormality. An example of a situation corresponding to fluctuation amount FL2 is a situation in which the other vehicle 30 is executing driving assistance control or automatic driving control, but the driver 31 of the other vehicle 30 is experiencing an abnormality, causing the fluctuation amount of the other vehicle 30 to increase to the level of fluctuation amount FL2. Fluctuation amount FL2 may or may not include fluctuation amounts due to external factors such as wind or road conditions.

[0038] At the fluctuation amount FL2, an abnormality has occurred in the driver 31 of the other vehicle 30, and therefore, there is a possibility that the fluctuation amount of the other vehicle 30 will increase to the level of the fluctuation amount FL1 in the future. Therefore, the ECU 10 changes the fluctuation threshold value so as to make it easier to determine that the other vehicle 30 is in an abnormal fluctuation state. That is, the abnormal state determination unit 14 determines whether or not the other vehicle 30 is in an abnormal fluctuation state by setting the fluctuation threshold value Th2, which is used when an abnormality in the driver 31 of the other vehicle 30 is recognized, to a smaller absolute value than the fluctuation threshold value Th1, which is used when an abnormality in the driver 31 of the other vehicle 30 is not recognized. The fluctuation threshold value Th2 is a value smaller than the preset fluctuation threshold value Th1, and can be set based on the results of a prior test drive or the like.

[0039] As a result, in the example of Fig. 4, the fluctuation amount FL2 is at the same level as the fluctuation amount FL9 in Fig. 3. By changing the fluctuation threshold based on whether or not an abnormality in the driver 31 of the other vehicle 30 is recognized, it is determined that there is no abnormal fluctuation state in the example of Fig. 3, and that there is an abnormal fluctuation state in the example of Fig. 4.

[0040] The notification control unit 15 notifies the occupants of the host vehicle 20. For example, the notification control unit 15 notifies the driver by at least one of an image display on a display and an audio output from a speaker, by sending a control signal to the HMI 7. The notification control unit 15 may also notify the driver by combining vibrations of the steering wheel, seat, seatbelt, pedal vibrations, or reaction force of the host vehicle 20.

[0041] When the abnormal state determination unit 14 determines that the other vehicle 30 is in an abnormal sway state, the notification control unit 15 notifies the occupants of the host vehicle 20 about the abnormal sway state. When the amount of sway of the other vehicle 30 is greater than a sway threshold, the notification control unit 15 notifies the occupants of the host vehicle 20 about the abnormal sway state.

[0042] The vehicle control unit 16 can execute vehicle control including driving assistance control and automatic driving control of the host vehicle 20. The vehicle control unit 16 controls the host vehicle 20 by sending a control signal to the actuator 6. In driving assistance control, driving assistance (applying a steering amount, changing a steering reaction force, and changing the vehicle speed, acceleration, and deceleration) is performed so that the host vehicle 20 travels along a target driving trajectory. In automatic driving control, the vehicle is controlled so that the host vehicle 20 travels along a target driving trajectory.

[0043] Vehicle control includes avoidance control of the host vehicle 20. Avoidance control is control for automatically avoiding danger to the host vehicle 20. Avoidance control includes lane changes, obstacle avoidance control, acceleration control, and stop control (evacuation) to the shoulder of the road. When the abnormal state determination unit 14 determines that the other vehicle 30 is in an abnormal sway state, the vehicle control unit 16 may suggest avoidance control to the occupants of the host vehicle 20. When avoiding danger requires urgent action, the vehicle control unit 16 may omit the suggestion and execute avoidance control of the host vehicle 20.

[0044] [Example of ECU processing] Next, an example of the calculation processing by the ECU 10 will be described. Fig. 5 is a flowchart showing an example of the processing by the driving support device of Fig. 1. The processing shown in Fig. 5 is repeatedly performed at a predetermined cycle, for example, while the host vehicle 20 is traveling.

[0045] 5, in step S11, the ECU 10 recognizes the amount of fluctuation of another vehicle by the fluctuation amount recognition unit 12. The fluctuation amount recognition unit 12 recognizes the amount of fluctuation of another vehicle 30 traveling around the host vehicle 20 based on the detection result of the external sensor 1 or the external camera 2 provided on the host vehicle 20.

[0046] In step S12, the ECU 10 causes the fluctuation amount recognition unit 12 to recognize the external environment of the host vehicle 20 and correct the fluctuation amount of the other vehicle 30. The fluctuation amount recognition unit 12 recognizes the road surface conditions of the road 50 on which the host vehicle 20 and the other vehicle 30 are traveling, for example, based on an image captured by the external camera 2, and corrects the fluctuation amount of the other vehicle 30 based on the road surface conditions.

[0047] In step S13, the ECU 10 compares the amount of fluctuation of the other vehicle 30 with the fluctuation threshold value using the abnormal state determination unit 14. The abnormal state determination unit 14 determines, for example, whether the amount of fluctuation of the other vehicle 30 is greater than the fluctuation threshold value Th1.

[0048] If the abnormal state determination unit 14 determines that the fluctuation amount of the other vehicle 30 is greater than the fluctuation threshold Th1 (step S13: YES), the ECU 10 proceeds to step S14. In step S14, the ECU 10 causes the abnormal state determination unit 14 to determine that the other vehicle 30 is in an abnormal fluctuation state. That is, the abnormal state determination unit 14 determines whether or not the other vehicle 30 is in an abnormal fluctuation state based on the result of comparing the fluctuation amount of the other vehicle 30 with the fluctuation threshold.

[0049] In step S15, the ECU 10 executes a notification regarding the abnormal fluctuation state by the notification control unit 15. The notification control unit 15, for example, uses the HMI 7 provided in the host vehicle 20 to display an image or output a sound regarding the abnormal fluctuation state to the occupants of the host vehicle 20. Thereafter, the ECU 10 ends the processing of FIG. 5.

[0050] On the other hand, if the abnormal state determination unit 14 determines that the fluctuation amount of the other vehicle 30 is equal to or less than the fluctuation threshold Th1 (step S13: NO), the ECU 10 proceeds to step S16. In step S16, the ECU 10 causes the driver abnormality recognition unit 13 to recognize an abnormality in the driver of the other vehicle 30. The driver abnormality recognition unit 13 recognizes an abnormality in the driver of the other vehicle 30 based on an image captured by the external camera 2 provided on the host vehicle 20.

[0051] In step S17, the ECU 10 determines whether or not the abnormal state determination unit 14 has recognized an abnormality in the driver 31 of the other vehicle 30. If the ECU 10 determines that the abnormal state determination unit 14 has recognized an abnormality in the driver 31 of the other vehicle 30 (step S17: YES), the ECU 10 proceeds to step S18. On the other hand, if the ECU 10 determines that the abnormal state determination unit 14 has not recognized an abnormality in the driver 31 of the other vehicle 30 (step S17: NO), the ECU 10 proceeds to step S19.

[0052] In step S18, the ECU 10 compares the amount of fluctuation of the other vehicle 30 with the fluctuation threshold value using the abnormal state determination unit 14. The abnormal state determination unit 14 determines, for example, whether the amount of fluctuation of the other vehicle 30 is greater than the fluctuation threshold value Th2.

[0053] If the abnormal state determination unit 14 determines that the fluctuation amount of the other vehicle 30 is greater than the fluctuation threshold Th2 (step S18: YES), the ECU 10 proceeds to the above-mentioned step S14. In the above-mentioned step S14, the ECU 10 determines that the other vehicle 30 is in an abnormal fluctuation state using the abnormal state determination unit 14. That is, the abnormal state determination unit 14 determines whether or not the other vehicle 30 is in an abnormal fluctuation state based on the result of comparing the fluctuation amount of the other vehicle 30 with the fluctuation threshold.

[0054] On the other hand, if the abnormal state determination unit 14 determines that the fluctuation amount of the other vehicle 30 is equal to or less than the fluctuation threshold value Th2 (step S18: NO), the ECU 10 proceeds to step S19. In step S19, the ECU 10 determines that the other vehicle 30 is not in an abnormal fluctuation state using the abnormal state determination unit 14. Thereafter, the ECU 10 ends the processing of FIG. 5.

[0055] According to the driving assistance device 100 described above, whether or not there is an abnormal fluctuation state is determined by setting the fluctuation threshold Th2 when an abnormality in the driver 31 of the other vehicle 30 is recognized as a smaller absolute value than the fluctuation threshold Th1 when an abnormality in the driver 31 of the other vehicle 30 is not recognized. As a result, even if the fluctuation amount FL9 when an abnormality in the driver 31 of the other vehicle 30 is not recognized and the other vehicle 30 is swaying due to an external environment such as wind or road conditions is about the same as the fluctuation amount FL2 when an abnormality in the driver 31 of the other vehicle 30 is recognized, it is more likely that there is an abnormal fluctuation state when an abnormality in the driver 31 of the other vehicle 30 is recognized. Therefore, according to the driving assistance device 100, driving assistance including notification to the occupants of the host vehicle 20 can be performed depending on the cause of the fluctuation amount of the other vehicle 30.

[0056] The fluctuation amount recognition unit 12 recognizes the road surface conditions of the road 50 on which the host vehicle 20 and the other vehicle 30 are traveling based on the image captured by the external camera 2, and corrects the fluctuation amount of the other vehicle 30 based on the road surface conditions. By using the fluctuation amount FL2 corrected based on the road surface conditions, it is possible to more appropriately determine whether the other vehicle 30 is in an abnormal fluctuation state depending on the road surface conditions.

[0057] [Variations] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. The present invention can be embodied in various forms, including the above-described embodiments, with various modifications and improvements made based on the knowledge of those skilled in the art.

[0058] In the above embodiment, the fluctuation amount recognition unit 12 corrects the fluctuation amount of the other vehicle 30 based on, for example, road surface conditions. However, the fluctuation threshold may also be corrected. FIG. 6 is a diagram illustrating an example of a fluctuation threshold corrected according to road surface conditions when an abnormality in the driver of the other vehicle is recognized. In FIG. 6, the fluctuation amounts FL0 and FL1 are the same as those shown in FIGS. 3 and 4. The fluctuation amount FL3 is a fluctuation amount in which the fluctuation amount of the other vehicle 30 as seen from the host vehicle 20 appears smaller than the fluctuation amount FL2 as a result of, for example, the influence of the rut 51 in FIG. 2 causing the host vehicle 20 to move in the vehicle width direction in phase with the fluctuation amount of the other vehicle 30. Therefore, the ECU 10 may change the fluctuation threshold from the fluctuation threshold Th2 to the fluctuation threshold Th3 so that it becomes easier to determine that the other vehicle 30 is in an abnormal fluctuation state even with the apparently smaller fluctuation amount FL3. That is, the abnormal state determination unit 14 may recognize the road surface conditions of the road 50 on which the host vehicle 20 and the other vehicle 30 are traveling based on the image captured by the external camera 2, and correct the fluctuation threshold value based on the road surface conditions. The fluctuation threshold value Th3 may be set in advance based on the results of a prior test drive, for example.

[0059] Fig. 7 is a flowchart showing the processing of the driving assistance device 100 according to a modified example. The processing shown in Fig. 7 is repeatedly performed at a predetermined cycle, for example, while the host vehicle 20 is traveling. In the flowchart of Fig. 7, steps S12A and S18A are different from the flowchart of Fig. 5, but the other processing is the same.

[0060] In step S12A, the ECU 10 causes the fluctuation amount recognition unit 12 to recognize the external environment of the host vehicle 20 and correct the fluctuation threshold. The fluctuation amount recognition unit 12 recognizes the road surface conditions of the road 50 on which the host vehicle 20 and the other vehicle 30 are traveling, for example, based on an image captured by the external camera 2, and corrects the fluctuation threshold based on the road surface conditions. In the example of Fig. 6, the fluctuation amount recognition unit 12 corrects the fluctuation threshold Th2 in Fig. 4 to a fluctuation threshold Th3 based on the road surface conditions.

[0061] In step S18A, the ECU 10 causes the abnormal state determination unit 14 to compare the amount of fluctuation of the other vehicle 30 with the fluctuation threshold value. The abnormal state determination unit 14 determines, for example, whether the amount of fluctuation of the other vehicle 30 is greater than the fluctuation threshold value Th3.

[0062] If the abnormal state determination unit 14 determines that the amount of fluctuation of the other vehicle 30 is greater than the fluctuation threshold value Th3 (step S18A: YES), the ECU 10 proceeds to the above-mentioned step S14. On the other hand, if the abnormal state determination unit 14 determines that the amount of fluctuation of the other vehicle 30 is equal to or less than the fluctuation threshold value Th3 (step S18A: NO), the ECU 10 proceeds to step S19.

[0063] According to the driving assistance device 100 of the modified example described above, the fluctuation amount recognition unit 12 recognizes the road surface conditions of the road 50 on which the host vehicle 20 and the other vehicle 30 are traveling, based on the images captured by the external camera 2, and corrects the fluctuation threshold of the other vehicle 30 based on the road surface conditions. As a result, by using the fluctuation threshold Th3 corrected based on the road surface conditions, it is possible to more appropriately determine whether the other vehicle 30 is in an abnormal fluctuation state depending on the road surface conditions.

[0064] In the above embodiment, the driving assistance device 100 is capable of executing automatic driving control, but this is not essential, and it is sufficient if it is at least capable of notifying the occupants of the host vehicle 20.

[0065] In the above embodiment, the abnormal state determination unit 14 determines that the other vehicle 30 is in an abnormal fluctuation state when, for example, the fluctuation amount of the other vehicle 30 is greater than the fluctuation threshold value, but this is not limited to this. The fluctuation amount may be defined, for example, with a sign, so that the other vehicle 30 is determined to be in an abnormal fluctuation state when the fluctuation amount of the other vehicle 30 is smaller than the fluctuation threshold value. [Explanation of symbols]

[0066] 1...External sensor, 2...External camera, 12...Fluctuation amount recognition unit, 13...Driver abnormality recognition unit, 14...Abnormal state determination unit, 15...Notification control unit, 20...Own vehicle (vehicle), 30...Other vehicle, 31...Driver, 50...Road, 51...Ruts (road surface conditions), 100...Driving assistance device, FL0, FL1, FL2, FL3, FL9...Fluctuation amount, Th1, Th2, Th3...Fluctuation threshold.

Claims

1. A driving assistance device that provides driving assistance including notification to vehicle occupants, a fluctuation amount recognition unit that recognizes a fluctuation amount of another vehicle traveling around the vehicle based on a detection result of an external sensor provided on the vehicle; a driver abnormality recognition unit that recognizes an abnormality in a driver of the other vehicle based on an image captured by an external camera provided in the vehicle; an abnormal state determination unit that determines whether the other vehicle is in an abnormal fluctuation state based on a comparison result between the fluctuation amount of the other vehicle and a fluctuation threshold; a notification control unit that issues the notification regarding the fluctuation abnormal state, The abnormal state determination unit determines whether the fluctuation threshold is in an abnormal state by setting the fluctuation threshold when an abnormality in the driver of the other vehicle is recognized to an absolute value that is smaller than the fluctuation threshold when an abnormality in the driver of the other vehicle is not recognized.

2. A driving assistance device as described in claim 1, wherein the fluctuation threshold when no abnormality is recognized in the driver of the other vehicle is pre-set to be greater than the amount of fluctuation of the other vehicle when there is no abnormality in the driver of the other vehicle and the other vehicle is fluctuating due to the external environment of the other vehicle.

3. 3. The driving assistance device according to claim 1, wherein the fluctuation amount recognition unit recognizes road surface conditions of a road on which the vehicle and the other vehicle are traveling based on an image captured by the external camera, and corrects the fluctuation amount of the other vehicle based on the road surface conditions.

4. A driving assistance device as described in claim 1 or 2, wherein the fluctuation amount recognition unit corrects the fluctuation amount of the other vehicle based on the wind speed when the wind speed in the weather information received by the communication unit of the vehicle becomes equal to or greater than a certain level.

5. A driving assistance device as described in claim 1 or 2, wherein the driver abnormality recognition unit estimates that there is an abnormality in the driver of the other vehicle when the head of the driver of the other vehicle is not present within a certain range including the driver's seat of the other vehicle that is visible through the windshield of the other vehicle in a frontal view of the other vehicle, based on an image captured by a rear camera installed in the vehicle.

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