Driving Support Devices

Abstract

To provide a driving support device that, even when the front of a vehicle is blocked during autonomous driving, can control the travel state of the vehicle according to the state of a preceding vehicle.SOLUTION: A driving support device comprises: a traffic light detection unit (detection unit) that repeatedly detects a traffic light ahead of a vehicle; a distance estimation unit (estimation unit) that estimates the distance to the traffic light; a preceding vehicle stop determination unit (determination unit) that determines if a vehicle preceding the vehicle stops at the traffic light; a vehicle control unit (control unit) that, when the traffic light detection unit becomes unable to detect the traffic light and when the distance to the last-detected traffic light is within a predetermined distance and the preceding vehicle stop determination unit determines that the vehicle preceding the vehicle does not stop at the traffic light, performs deceleration control of the vehicle until the traffic light detection unit becomes able to detect a traffic light; and a control detail notification unit (notification unit) that notifies a driver of the vehicle of the details of control performed by the vehicle control unit.SELECTED DRAWING: Figure 4

Description

[Technical field]

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

[0002] 2. Description of the Related Art Recently, driving assistance devices that assist a driver in accelerator operation and steering operation when driving a vehicle have been put into practical use.

[0003] For example, Patent Document 1 discloses a driving assistance device equipped with a function for avoiding a collision with a preceding vehicle. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2022-112350 Summary of the Invention [Problem to be solved by the invention]

[0005] The driving assistance device disclosed in Patent Document 1 operates on the premise that it can recognize both the preceding vehicle and the road environment ahead. However, when a large truck is traveling ahead of the vehicle, the road environment ahead, for example, traffic lights, is blocked, making it impossible to recognize the state of the traffic lights. As a result, there is a possibility that driving assistance cannot be continued.

[0006] An object of the present invention is to provide a driving assistance device that can control the driving state of a vehicle in accordance with the state of a preceding vehicle, even if the front of the vehicle is obstructed during autonomous driving. [Means for solving the problem]

[0007] In order to achieve the above object, a driving assistance device according to the present invention includes a detection unit that repeatedly detects a traffic light ahead of a vehicle, an estimation unit that estimates a distance to the traffic light, a determination unit that determines whether a vehicle preceding the vehicle will stop at the traffic light, and when the detection unit is no longer able to detect the traffic light, the distance to the last detected traffic light is within a predetermined distance, and the determination unit determines that the vehicle preceding the vehicle will not stop at the traffic light, performs deceleration control of the vehicle until the detection unit can detect the traffic light. When the detection unit is unable to detect the traffic light and the distance to the last detected traffic light is equal to or greater than a predetermined distance, the vehicle is caused to follow the preceding vehicle. The vehicle includes a control unit and a notification unit that notifies a driver of the vehicle of the contents of the control performed by the control unit.

[0008] According to this configuration, even if the front of the vehicle is obstructed during autonomous driving, the state of the preceding vehicle can be detected. and the distance to the traffic light The running state of the vehicle can be controlled according to the above.

[0009] In addition, in the driving assistance device of the present invention, when the detection unit is no longer able to detect the traffic light, the distance to the last detected traffic light is within a predetermined distance, and the judgment unit judges that a vehicle preceding the vehicle will stop at the traffic light, the control unit causes the vehicle to follow the preceding vehicle.

[0010] According to this configuration, even if the front of the vehicle is obstructed during autonomous driving, the driving state of the vehicle can be controlled according to the state of the leading vehicle.

[0013] In addition, in the driving assistance device of the present invention, the judgment unit determines whether the preceding vehicle will stop at the traffic light based on the distance to the traffic light estimated by the estimation unit, the vehicle speed of the vehicle, and the rate of change of the inter-vehicle distance between the vehicle and the preceding vehicle.

[0014] According to this configuration, the state of the preceding vehicle can be estimated simply and reliably. Effect of the Invention

[0015] According to the present invention, even if a traffic light is blocked, the traveling state of the vehicle can be controlled in accordance with the state of the preceding vehicle. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a diagram illustrating a problem with a conventional driving support device. [Diagram 2] FIG. 2 is a diagram illustrating the control content of the driving support device according to the embodiment. [Diagram 3] FIG. 3 is a hardware block diagram illustrating an example of a hardware configuration of the driving assistance device according to the embodiment. [Figure 4] FIG. 4 is a functional block diagram illustrating an example of a functional configuration of the driving assistance device according to the embodiment. [Diagram 5] FIG. 5 is a flowchart illustrating an example of a flow of processing performed by the driving assistance device according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0018] (Overview of operation of driving support device) An outline of the operation of the driving support device of the first embodiment of the present invention will be described with reference to Figures 1 and 2. Figure 1 is a diagram for explaining the problems of the conventional driving support device. Figure 2 is a diagram for explaining the control contents of the driving support device of the first embodiment.

[0019] A vehicle 1 equipped with a driving assistance device 10 (see FIG. 3) recognizes the road environment on which it is traveling, and if there are no obstacles, it travels at a speed equal to or lower than a set vehicle speed while maintaining a preset distance from a preceding vehicle 2. This type of traveling state is referred to as automatic driving.

[0020] The driving support device 10 detects an obstacle (e.g., a preceding vehicle 2) ahead of the vehicle 1 using a camera 22 installed in front of the vehicle 1 or a distance measuring device such as a lidar or radar installed on the front bumper of the vehicle 1. Then, the driving support device 10 automatically drives the vehicle 1 while maintaining a preset distance between the vehicle and the detected obstacle. The camera 22 also detects a traffic light 3 ahead in the traveling direction and recognizes the light color of the traffic light 3. The driving support device 10 judges whether to continue the automatic driving or to decelerate according to the light color of the recognized traffic light 3.

[0021] If the road ahead of the vehicle 1 is open, the various controls described above are executed, but as shown in Fig. 1, if there is a large preceding vehicle 2 ahead of the vehicle 1, the preceding vehicle 2 may block the visual field 22a of the camera 22. In this state, the camera 22 will not be able to recognize the traffic light 3.

[0022] In order to prevent such blocking of the traffic light 3, there are some intersections where the traffic light 3 is also installed on the opposite lane. However, it is difficult to install the traffic light 3 on the opposite lane at all intersections. The driving support device 10 of this embodiment assumes that such blocking of the traffic light 3 will occur, and controls the running state of the vehicle 1 based on the running state of the vehicle 2 preceding the vehicle 1 even if the traffic light 3 is blocked.

[0023] 2 shows the contents of the control performed by the driving assistance device 10 of this embodiment when the traffic light 3 is blocked. First, it is assumed that the vehicle 1 detects the traffic light 3 at time t=t1 during autonomous driving and estimates the distance D1 to the traffic light 3. Then, it is assumed that a large preceding vehicle 2 then enters in front of the vehicle 1.

[0024] At this time, if the driving assistance device 10 determines that the distance D1 to the traffic light 3 at time t=t1 is within a predetermined distance Dth and that the preceding vehicle 2 will not stop at the traffic light 3, the driving assistance device 10 decelerates the vehicle 1.

[0025] The predetermined distance Dth is a preset value, and is set, for example, to a distance that allows the vehicle 1 to pass the traffic light 3 within the predetermined time T if the vehicle 1 continues traveling at the current vehicle speed. The predetermined time T is set, for example, to a value of 2 seconds or less. More specifically, the predetermined time T is set to a value equivalent to the time from when the traffic light 3 turns off green, through yellow, and until it turns red.

[0026] Whether the preceding vehicle 2 will stop at the traffic light 3 can be estimated, for example, from the distance D1 from the vehicle 1 to the traffic light 3, the vehicle speed of the vehicle 1, and the change in the inter-vehicle distance D2 between the vehicle 1 and the preceding vehicle 2, i.e., the relative speed of the preceding vehicle 2 with respect to the vehicle 1. Specifically, for example, when the preceding vehicle 2 traveling at a vehicle speed estimated from the relative speed of the preceding vehicle 2 with respect to the vehicle 1 can travel a distance equivalent to the difference between the distance D1 and the inter-vehicle distance D2 within a predetermined time T, it is estimated that the preceding vehicle 2 will not stop at the traffic light 3. On the other hand, when the preceding vehicle 2 cannot travel a distance equivalent to the difference between the distance D1 and the inter-vehicle distance D2 within the predetermined time T, it is estimated that the preceding vehicle 2 will stop at the traffic light 3.

[0027] Then, when the driving assistance device 10 determines that the preceding vehicle 2 will not stop at the traffic light 3, it slows down the vehicle 1 so that the inter-vehicle distance D2 with the preceding vehicle 2 increases, and when the camera 22 is able to detect the traffic light 3 again, it resumes automatic driving.

[0028] On the other hand, if the distance D1 to the traffic light 3 at time t=t1 is within the predetermined distance Dth and it is determined that the preceding vehicle 2 will not stop at the traffic light 3, the driving assistance device 10 continues the automatic driving of the vehicle 1, i.e., continues following control of the preceding vehicle 2.

[0029] Furthermore, the driving assistance device 10 continues the automatic driving of the vehicle 1, that is, the following control for the preceding vehicle 2, even if the distance D1 to the traffic light 3 at time t=t1 is equal to or greater than the predetermined distance Dth.

[0030] (Hardware configuration of driving assistance device) The hardware configuration of the driving support device 10 will be described with reference to Fig. 3. Fig. 3 is a hardware block diagram showing an example of the hardware configuration of the driving support device of the first embodiment.

[0031] The driving assistance device 10 includes a plurality of ECUs (Electronic Control Units) for controlling each part of the vehicle 1. Each ECU includes a microcontroller unit (microcomputer). The microcomputer includes a CPU, a non-volatile memory such as a flash memory, and a volatile memory such as a dynamic random access memory (DRAM).

[0032] The multiple ECUs include a steering ECU 13, a drive ECU 15, and a braking ECU 17. The steering ECU 13, the drive ECU 15, and the braking ECU 17 are connected via a bus 12 so as to enable communication according to a CAN (Controller Area Network) communication protocol, that is, CAN communication.

[0033] The steering ECU 13 is a control unit that controls the steering device 14 of the vehicle 1. The steering device 14 is, for example, an electric power steering device that applies the torque of an electric motor to a steering mechanism. The steering mechanism includes, for example, a rack-and-pinion steering gear, and is configured such that when a rack shaft moves in the vehicle width direction due to the torque of the electric motor, the left and right steered wheels are turned left and right in accordance with the movement of the rack shaft.

[0034] The drive ECU 15 is a control unit that controls the drive device 16 of the vehicle 1. The drive device 16 may be configured to include an engine as a drive source, a motor as a drive source, or both an engine and a motor as drive sources. The drive device 16 includes a transmission that changes the speed of the drive force from the drive source and outputs it as necessary.

[0035] The brake ECU 17 is a control unit that controls a braking device 18 of the vehicle 1. The braking device 18 may be of a hydraulic type or an electric type. The hydraulic braking device 18 includes a brake actuator, and the function of this brake actuator distributes hydraulic pressure to wheel cylinders of the brakes provided on each wheel, and the hydraulic pressure applies braking force from each brake to the wheels including the driving wheels.

[0036] The aforementioned multiple ECUs include an automatic driving ECU 11, a camera ECU 21, a lidar ECU 23, and the like, as control units for the automatic driving function.

[0037] The automatic driving ECU 11 is the control center of automatic driving control. The automatic driving ECU 11 executes a control program in its own CPU, thereby controlling the driving assistance device 10 in an overall manner. The automatic driving ECU 11 is connected to the steering ECU 13, the drive ECU 15, and the braking ECU 17 so as to be able to communicate via CAN. Specific functions of the automatic driving ECU 11 will be described later (see FIG. 4).

[0038] The autonomous driving ECU 11 is connected to, for example, a camera ECU 21, a lidar ECU 23, a GPS receiver 25, a high-precision map database 26, a vehicle speed sensor 27, a monitor 28, and a speaker 29 via an Ethernet (registered trademark) standard bus 20.

[0039] The camera ECU 21 is connected to the automatic driving ECU 11 via the bus 20 so as to be able to communicate with the automatic driving ECU 11. The camera ECU 21 is connected to a camera 22. The camera 22 continuously captures still images of a visual field range 22a in front of the vehicle 1 at a predetermined frame rate. The camera ECU 21 receives image signals of still images continuously output from the camera 22. The camera ECU 21 outputs the image signals input from the camera 22 to the automatic driving ECU 11. The automatic driving ECU 11 recognizes the road alignment in front of the vehicle 1, the state of the traffic light 3, and the like by analyzing the image signals acquired from the camera ECU 21. The camera 22 may be a monochrome camera or a color camera. The camera 22 may be a monocular camera or a stereo camera.

[0040] The LIDAR ECU 23 is connected to the automatic driving ECU 11 via the bus 20 so as to be able to communicate with the LIDAR ECU 23. A plurality of LIDARs 24 are connected to the LIDAR ECU 23. The LIDAR 24 irradiates a search range with a laser light, receives reflected light from an object present within the search range with an optical sensor, and outputs a detection signal according to the intensity of the reflected light, i.e., the distance to the object. The LIDARs 24 are disposed, for example, at the left end, center, and right end of the front bumper of the vehicle 1 and the left end, center, and right end of the rear bumper. The LIDAR ECU 23 receives detection signals output from the plurality of LIDARs 24. The LIDAR ECU 23 processes the detection signals acquired from the plurality of LIDARs 24 and transmits data obtained by the processing to the automatic driving ECU 11. Specifically, the LIDAR ECU 23 processes the detection signals input from the plurality of LIDARs 24 to image the position of the object in the direction of each LIDAR 24. The driving assistance device 10 may include a radar ECU and a millimeter-wave radar connected to the radar ECU in addition to the LIDAR ECU 23. Generally, a millimeter-wave radar has a longer distance measurement range than the LIDAR 24, so that short-distance measurement may be performed by the LIDAR 24 and long-distance measurement may be performed by the millimeter-wave radar.

[0041] The GPS receiver 25 is a receiver that receives positioning signals from multiple GPS (Global Positioning System) satellites. The multiple positioning signals received by the GPS receiver 25 are input from the GPS receiver 25 to the automatic driving ECU 11. The automatic driving ECU 11 estimates the current position and traveling direction of the vehicle 1 from the multiple positioning signals. Note that the GPS receiver 25 itself may have a function of estimating the current position and traveling direction of the vehicle 1, and the current position and traveling direction estimated by the GPS receiver 25 may be input to the automatic driving ECU 11.

[0042] The high-precision map database 26 is data including, for example, information on road width and gradient, and information on features such as dividing lines, shoulder lines, intersections, railroad crossings, stop lines, pedestrian crossings, traffic lights, and signs. The autonomous driving ECU 11 verifies the current position of the vehicle 1 estimated based on the positioning signal from the GPS receiver 25 against the contents of the high-precision map database 26, thereby identifying the position of the vehicle 1 on the road. The high-precision map database 26 may be stored in a non-volatile memory built into a microcomputer of the autonomous driving ECU 11, or may be stored in a hard disk drive (HDD) (not shown) connected to the autonomous driving ECU 11.

[0043] The vehicle speed sensor 27 detects the speed of the vehicle 1 .

[0044] The monitor 28 notifies the driver by displaying graphic information and text information related to the operating state of the driving assistance device 10, which is generated by the autonomous driving ECU 11. The monitor 28 is, for example, a liquid crystal monitor or an organic EL monitor.

[0045] The speaker 29 notifies the driver by outputting sounds and voices generated by the autonomous driving ECU 11 and related to the operating state of the driving assistance device 10.

[0046] 3 is an example, and various modifications are possible to realize the same functions. Also, different sensors and actuators may be provided to realize the same functions.

[0047] (Functional configuration of driving assistance device) The functional configuration of the driving support device 10 will be described with reference to Fig. 4. Fig. 4 is a functional block diagram showing an example of the functional configuration of the driving support device of the first embodiment. Note that the functional block diagram of Fig. 4 shows the minimum configuration required for the automatic driving ECU 11 to realize the contents of the present invention.

[0048] The autonomous driving ECU 11 of the driving assistance device 10 causes its own CPU to execute a control program to realize, as functional units, a traffic light detection unit 31, a distance estimation unit 32, a vehicle speed detection unit 33, a vehicle distance detection unit 34, a preceding vehicle stop determination unit 35, a vehicle control unit 36, and a control content notification unit 37, all of which are shown in Fig. 4. Note that some or all of the functions of the autonomous driving ECU 11 may be realized by dedicated hardware.

[0049] The traffic light detection unit 31 repeatedly detects the state of the traffic light 3 ahead of the vehicle 1 and the time t at that time. The traffic light detection unit 31 is an example of the detection unit in the present invention.

[0050] The traffic light detection unit 31, for example, compares the image captured by the camera 22 with a traffic light recognition model generated by deep learning to detect whether the traffic light 3 is captured in the image, and if the traffic light 3 is captured, at least detects its position and light color. If a color camera is used as the camera 22, the light color can be detected more reliably. The traffic light detection unit 31 may be provided in the camera ECU 21. In that case, the camera ECU 21 outputs to the autonomous driving ECU 11 information indicating whether the traffic light 3 is captured, and if the traffic light 3 is captured, its position and light color.

[0051] The distance estimation unit 32 estimates a distance D1 to the traffic light 3 ahead of the vehicle 1. Specifically, the distance estimation unit 32 estimates the distance D1 from the vehicle 1 to the traffic light 3 based on the apparent size of the traffic light 3 detected by the traffic light detection unit 31. Since the size of the traffic light 3 is known, the distance D1 can be estimated based on the apparent size of the traffic light 3 detected by the traffic light detection unit 31 and the actual size of the traffic light 3. In addition, when the installation position of the traffic light 3 is stored in the high-precision map database 26, the distance estimation unit 32 may estimate the distance D1 based on the current position of the vehicle 1 measured based on the positioning signal of the GPS receiver 25 and the installation position of the traffic light 3. The distance estimation unit 32 is an example of an estimation unit in the present invention.

[0052] Further, the distance estimation unit 32 determines whether the last estimated distance D1 to the traffic light 3 is within a predetermined distance Dth.

[0053] The vehicle speed detection unit 33 detects the speed of the vehicle 1 based on the output of the vehicle speed sensor 27 .

[0054] The inter-vehicle distance detection unit 34 detects the inter-vehicle distance D2 between the vehicle 1 and the preceding vehicle 2 and the rate of change of the inter-vehicle distance D2 by repeatedly detecting the output of the lidar 24 that is installed facing forward.

[0055] The preceding vehicle stop determination unit 35 determines whether the preceding vehicle 2 of the vehicle 1 will stop at the traffic light 3. The preceding vehicle stop determination unit 35 is an example of a determination unit in the present invention.

[0056] When the traffic light detection unit 31 is no longer able to detect the state of the traffic light 3, the distance D1 to the last detected traffic light 3 is within a predetermined distance Dth, and the preceding vehicle stop determination unit 35 determines that the preceding vehicle 2 of the vehicle 1 will not stop at the traffic light 3, the vehicle control unit 36 ​​performs deceleration control of the vehicle 1 until the traffic light detection unit 31 can detect the traffic light 3.

[0057] Furthermore, when the traffic light detection unit 31 is unable to detect the state of the traffic light 3, the distance D1 to the last detected traffic light 3 is equal to or greater than the predetermined distance Dth, and the preceding vehicle stop determination unit 35 determines that the preceding vehicle 2 of the vehicle 1 will stop at the traffic light 3, the vehicle control unit 36 ​​causes the vehicle 1 to continue the automatic driving. More specifically, the vehicle control unit 36 ​​causes the vehicle 1 to follow the preceding vehicle 2.

[0058] Furthermore, when the traffic light detection unit 31 is unable to detect the traffic light 3 and the distance D1 to the last detected traffic light 3 is equal to or greater than the predetermined distance Dth, the vehicle control unit 36 ​​causes the vehicle 1 to continue the automatic driving. More specifically, the vehicle control unit 36 ​​causes the vehicle 1 to follow the preceding vehicle 2. The vehicle control unit 36 ​​is an example of a control unit in the present invention.

[0059] The control content notification unit 37 notifies the driver of the vehicle 1 of the content of the control performed by the vehicle control unit 36. Specifically, the control content notification unit 37 notifies the driver of the control content by displaying the control content performed by the vehicle 1 on the monitor 28. The control content notification unit 37 also notifies the driver of the control content by outputting the control content performed by the vehicle 1 as audio from the speaker 29. The control content notification unit 37 is an example of a notification unit in the present invention.

[0060] (Processing flow performed by the driving assistance device) The flow of processing performed by the driving support device 10 will be described with reference to Fig. 5. Fig. 5 is a flowchart showing an example of the flow of processing performed by the driving support device of the first embodiment.

[0061] The vehicle control unit 36 ​​starts the automatic driving of the vehicle 1 (step S11).

[0062] The traffic light detection unit 31 determines whether the traffic light 3 has been detected (step S12). If it is determined that the traffic light 3 has been detected (step S12: Yes), the process proceeds to step S13. On the other hand, if it is determined that the traffic light 3 has not been detected (step S12: No), step S12 is repeated.

[0063] When it is determined in step S12 that the traffic light 3 has been detected, the distance estimation unit 32 estimates the distance D1 from the vehicle 1 to the traffic light 3 (step S13).

[0064] Thereafter, the traffic light detection unit 31 determines whether the traffic light 3 cannot be detected (step S14). If it is determined that the traffic light 3 cannot be detected (step S14: Yes), the process proceeds to step S15. On the other hand, if it is not determined that the traffic light 3 cannot be detected (step S14: No), that is, if it is determined that the traffic light 3 can be detected, the process returns to step S13.

[0065] If it is determined in step S14 that the traffic light 3 cannot be detected, the distance estimation unit 32 determines whether the last estimated distance D1 to the traffic light 3 is within the predetermined distance Dth (step S15). If it is determined that the last estimated distance D1 to the traffic light 3 is within the predetermined distance Dth (step S15: Yes), the process proceeds to step S16. On the other hand, if it is not determined that the last estimated distance D1 to the traffic light 3 is within the predetermined distance Dth (step S15: No), the process proceeds to step S19.

[0066] If it is determined in step S15 that the last estimated distance D1 to the traffic light 3 is within the predetermined distance Dth, the leading vehicle stop determination unit 35 determines whether the leading vehicle 2 of the vehicle 1 will stop at the traffic light 3 (step S16). If it is determined that the leading vehicle 2 will not stop at the traffic light 3 (step S16: Yes), the process proceeds to step S17. On the other hand, if it is not determined that the leading vehicle 2 will not stop at the traffic light 3 (step S16: No), that is, if it is determined that the leading vehicle 2 will stop at the traffic light 3, the process proceeds to step S19.

[0067] If it is determined in step S16 that the leading vehicle 2 will not stop at the traffic light 3, the vehicle control unit 36 ​​performs deceleration control of the vehicle 1 (step S17).

[0068] Then, the control content notification unit 37 notifies the driver of the vehicle 1 that the vehicle 1 will decelerate (step S18). After that, the driving assistance device 10 ends the process of FIG.

[0069] On the other hand, if in step S15 it is not determined that the last estimated distance D1 to the traffic light 3 is within the predetermined distance Dth, or in step S16 it is not determined that the preceding vehicle 2 will not stop at the traffic light 3, the vehicle control unit 36 ​​causes the vehicle 1 to continue automatic driving so as to follow the preceding vehicle 2 (step S19).

[0070] Then, the control content notification unit 37 notifies the driver of the vehicle 1 that the vehicle 1 will continue the autonomous driving (step S20). After that, the driving assistance device 10 ends the process of FIG.

[0071] 5, the control contents performed by the driving support device 10 on the vehicle 1 performing automatic driving have been described, but the driving support device 10 may perform the same control contents when the driver is driving the vehicle 1 by himself / herself. Specifically, when the vehicle 1 is being manually driven, the driving support device 10 may activate the automatic brakes of the vehicle 1 when it is determined that it is necessary to decelerate the vehicle 1.

[0072] (Effects of the embodiment) As described above, the driving support device 10 of the embodiment includes a traffic light detection unit 31 (detection unit) that repeatedly detects the traffic light 3 in front of the vehicle 1, a distance estimation unit 32 (estimation unit) that estimates the distance D1 to the traffic light 3, a preceding vehicle stop determination unit 35 (determination unit) that determines whether the preceding vehicle 2 of the vehicle 1 will stop at the traffic light 3, a vehicle control unit 36 ​​(control unit) that performs deceleration control of the vehicle 1 until the traffic light detection unit 31 can detect the traffic light 3 when the traffic light detection unit 31 can no longer detect the traffic light 3, the distance D1 to the last detected traffic light 3 is within a predetermined distance Dth, and the preceding vehicle stop determination unit 35 determines that the preceding vehicle 2 of the vehicle 1 will not stop at the traffic light 3, and a control content notification unit 37 (notification unit) that notifies the driver of the vehicle 1 of the content of the control performed by the vehicle control unit 36. Therefore, even if the front of the vehicle 1 is blocked during automatic driving, the running state of the vehicle 1 can be controlled according to the state of the preceding vehicle 2.

[0073] Furthermore, in the driving assistance device 10 of the embodiment, when the traffic light detection unit 31 (detection unit) is unable to detect the traffic light 3, the distance D1 to the last detected traffic light 3 is within a predetermined distance Dth, and the preceding vehicle stop determination unit 35 (determination unit) determines that the preceding vehicle 2 of the vehicle 1 will stop at the traffic light 3, the vehicle control unit 36 ​​(control unit) causes the vehicle 1 to follow the preceding vehicle 2. Therefore, even if the front of the vehicle 1 is blocked during autonomous driving, the driving state of the vehicle 1 can be controlled according to the state of the preceding vehicle 2.

[0074] Furthermore, in the driving assistance device 10 of the embodiment, the vehicle control unit 36 ​​(control unit) causes the vehicle 1 to follow the preceding vehicle 2 when the traffic light detection unit 31 (detection unit) is unable to detect the traffic light 3 and the distance D1 to the last detected traffic light 3 is equal to or greater than a predetermined distance Dth. Therefore, even if the front of the vehicle 1 is blocked during autonomous driving, the traveling state of the vehicle 1 can be controlled according to the state of the preceding vehicle 2.

[0075] Furthermore, in the driving assistance device 10 of the embodiment, the preceding vehicle stop determination unit 35 determines whether the preceding vehicle 2 will stop at the traffic light 3 based on the distance D1 to the traffic light 3 estimated by the distance estimation unit 32 (estimation unit), the vehicle speed of the vehicle 1, and the rate of change of the inter-vehicle distance D2 between the vehicle 1 and the preceding vehicle 2. Therefore, the state of the preceding vehicle 2 can be estimated simply and reliably.

[0076] Although the embodiment of the present invention has been described above, the above-mentioned embodiment is presented as an example and is not intended to limit the scope of the present invention. This new embodiment can be embodied in various other forms. In addition, various omissions, substitutions, and modifications can be made without departing from the gist of the invention. In addition, this embodiment is included in the scope and gist of the invention, and is included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0077] 1 vehicle 2 Leading vehicle 3. Traffic lights 10 Driving assistance devices 11 Autonomous Driving ECU 22 Camera 27 Vehicle speed sensor 31 Traffic light detector (detector) 32 Distance estimation section (estimation section) 33 Vehicle speed detection unit 34 Vehicle distance detection unit 35 Leading vehicle stop determination unit (determination unit) 36 Vehicle control unit (control unit) 37 Control content notification unit (notification unit) D1 Distance D2 Following distance Dth specified distance T predetermined time

Claims

1. A detection unit that repeatedly detects a traffic light ahead of the vehicle; An estimation unit that estimates a distance to the traffic light; a determination unit that determines whether a preceding vehicle of the vehicle will stop at the traffic light; When the detection unit is unable to detect the traffic light, and the distance to the last detected traffic light is within a predetermined distance, and the determination unit determines that a preceding vehicle of the vehicle will not stop at the traffic light, the vehicle is decelerated until the detection unit can detect the traffic light. a control unit that causes the vehicle to follow the preceding vehicle when the detection unit is unable to detect the traffic light and the distance to the last detected traffic light is equal to or greater than a predetermined distance; A notification unit that notifies the driver of the vehicle of the contents of the control performed by the control unit. Driving assistance device.

2. When the detection unit is unable to detect the traffic light, the distance to the last detected traffic light is within a predetermined distance, and the determination unit determines that a preceding vehicle of the vehicle will stop at the traffic light, the control unit causes the vehicle to follow the preceding vehicle. The driving assistance device according to claim 1 .

3. The determination unit is determining whether the preceding vehicle will stop at the traffic light based on the distance to the traffic light estimated by the estimation unit, the vehicle speed of the vehicle, and a rate of change of a distance between the vehicle and a preceding vehicle; The driving assistance device according to claim 1 or 2.

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