Operation support device

Abstract

To provide an operation support device that can eliminate a situation where an own vehicle may interfere with traffic flow, so as to make the traffic flow smooth.SOLUTION: An operation support device 100 is provided with: a peripheral situation recognizing part 12 that recognizes a peripheral situation including a running state of the other vehicle running around an own vehicle; a running route obtaining part 14 that obtains a running route on which the own vehicle runs, on the basis of a running state of the own vehicle and the peripheral situation; and a lane change proposing part 15 that proposes lane change of the own vehicle to an occupant in the own vehicle, on the basis of the peripheral situation and the running route. When a lane mismatch condition for representing that selection of the lane on which the own vehicle is running is a mismatch in the light of the peripheral situation is satisfied on the basis of relative speed of the other vehicle to the own vehicle, the lane change proposing part 15 proposes lane change to a lane for a low-speed vehicle from the lane on which the own vehicle is running to the occupant.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] 2. Description of the Related Art Conventionally, there is known a technique for overtaking or not overtaking a preceding vehicle in the passing lane from a driving lane when the preceding vehicle in the passing lane is traveling at a speed slower than a set vehicle speed (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-15480 A Summary of the Invention [Problem to be solved by the invention]

[0004] For example, when a vehicle is traveling in the center lane of a three-lane road at or below the speed limit, the flow of other vehicles around the vehicle may be faster. If this situation occurs when there is a lane for slower vehicles than the lane in which the vehicle is traveling, there is a risk that the vehicle is obstructing the flow of traffic. [Means for solving the problem]

[0005] One aspect of the present invention includes a surrounding condition recognition unit that recognizes surrounding conditions including the driving conditions of other vehicles around the vehicle, a driving route acquisition unit that acquires a driving route along which the vehicle will travel based on the driving conditions and surrounding conditions of the vehicle, and a lane change suggestion unit that suggests to an occupant of the vehicle that the vehicle should change lanes based on the surrounding conditions and the driving route, and the lane change suggestion unit suggests to the occupant that the vehicle change lanes to a lane for slower vehicles than the lane in which the vehicle is traveling when a lane mismatch condition is established based on the relative speed of the other vehicles with respect to the vehicle, indicating that the selection of the lane in which the vehicle is traveling is a mismatch in light of the surrounding conditions.

[0006] In a driving assistance device according to an aspect of the present invention, when a lane mismatch condition is satisfied, which indicates that the selection of the lane in which the vehicle is traveling is mismatched in light of the surrounding circumstances, a lane change suggestion unit suggests to the occupant that the vehicle should change to a lane for slower vehicles than the lane in which the vehicle is traveling. For example, when the occupant accepts the suggestion, the lane is changed to a lane for slower vehicles, and the mismatch in the selection of the lane in which the vehicle is traveling is resolved. This makes it possible to resolve a situation in which the vehicle may be an obstacle to traffic flow, and to facilitate smooth traffic flow.

[0007] In one embodiment, the lane mismatch condition may be satisfied when another vehicle traveling in the lane behind the host vehicle changes lanes to a lane for slow vehicles and overtakes the host vehicle, or when another vehicle traveling in the lane for slow vehicles behind the host vehicle overtakes the host vehicle, in succession for a predetermined number of other vehicles. In this case, by satisfying the lane mismatch condition when the host vehicle is overtaken or passed by another vehicle by a certain number of times, it is possible to exclude the host vehicle from being subject to a lane change proposal even if the host vehicle is overtaken or passed by, for example, one other vehicle that is extremely faster than the host vehicle.

[0008] In one embodiment, when the lane mismatch condition is satisfied, the lane change suggesting unit may not suggest to the occupant that the vehicle should change to a lane for low-speed vehicles if the surrounding conditions correspond to a predetermined suggestion cancellation condition. In this case, when the surrounding conditions correspond to the predetermined suggestion cancellation condition, the vehicle may be less likely to obstruct traffic flow if the vehicle does not change lanes. Thus, traffic flow can be made smoother according to the surrounding conditions. Effect of the Invention

[0009] According to a driving assistance device according to an aspect of the present disclosure, it is possible to eliminate a situation in which the vehicle itself may obstruct traffic flow, thereby making it possible to facilitate smooth traffic flow. [Brief description of the drawings]

[0010] [Figure 1] 1 is a block diagram showing a driving assistance device according to an embodiment; [Diagram 2] FIG. 13 is a schematic plan view for explaining a case where a lane mismatch condition is met. [Diagram 3] FIG. 13 is a schematic plan view for explaining a case where the surrounding situation corresponds to a proposal cancellation situation. [Figure 4] FIG. 13 is a schematic plan view for explaining a case where the surrounding situation corresponds to a proposal cancellation situation. [Diagram 5] 1A is a schematic plan view for explaining a case where the surrounding situation corresponds to a proposal cancellation situation, and FIG. 1B is a schematic plan view for explaining a case where a lane mismatch condition is satisfied. [Figure 6] 2 is a flowchart showing an example of a process of an ECU in FIG. 1; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. In the following description, when simply referring to a "vehicle", it means the host vehicle, and when distinguishing between the host vehicle and another vehicle, it may be referred to as the "host vehicle".

[0012] FIG. 1 is a block diagram showing a driving assistance device according to an embodiment. As shown in FIG. 1, the driving assistance device 100 is mounted on a vehicle (own vehicle) such as a passenger car or a freight vehicle. The driving assistance device 100 executes driving assistance for a vehicle occupant including at least notifying the occupant of a proposed lane change. The driving assistance device 100 here is, as an example, a part of an automatic driving device that executes automatic driving control. The automatic driving control is vehicle control that autonomously drives a vehicle along a planned route without the driver performing driving operations. Note that some functions of the driving assistance device 100 may be executed on a server that can communicate with the vehicle.

[0013] [Configuration of driving support device] Hereinafter, a configuration of a driving support device 100 according to this embodiment will be described with reference to Fig. 1. As shown in Fig. 1, the driving support device 100 includes an ECU (Electronic Control Unit) 10 that performs overall system management.

[0014] The ECU 10 is an electronic control unit having a central processing unit (CPU) and a storage unit. The storage unit is composed of, for example, a read-only memory (ROM), a random access memory (RAM), and an electrically erasable programmable read-only memory (EEPROM). The ECU 10 realizes various functions by, for example, executing a program stored in the storage unit by the CPU. The ECU 10 may be composed of multiple electronic units.

[0015] The ECU 10 is connected to a GNSS receiver 1, an external sensor 2, an internal sensor 3, a map database 4, an actuator 5, and an HMI [Human Machine Interface] 6.

[0016] The GNSS receiver 1 measures the position of the vehicle (for example, the latitude and longitude of the vehicle) by receiving signals from positioning satellites. The GNSS receiver 1 transmits the measured vehicle position information to the ECU 10.

[0017] The external sensor 2 is a detection device that detects the situation around the vehicle. The external sensor 2 includes at least one of a camera and a radar sensor. The camera is an imaging device that captures the external situation of the vehicle. The camera is provided, for example, on the back side of the windshield of the vehicle and captures the image in front of the vehicle. The camera transmits the captured image related to the external situation of the vehicle to the ECU 10. The radar sensor is a detection device that detects objects around the vehicle using radio waves (for example, millimeter waves) or light. The objects around the vehicle include other vehicles traveling behind the vehicle. The radar sensor includes, for example, a millimeter wave radar or a LiDAR (Light Detection and Ranging). The radar sensor transmits information on the detected objects to the ECU 10.

[0018] The internal sensor 3 is a detection device that detects the running state of the vehicle. The internal sensor 3 includes a vehicle speed sensor. The vehicle speed sensor is a detector that detects the speed of the vehicle. As the vehicle speed sensor, for example, a wheel speed sensor that detects the rotation speed of the wheels of the vehicle or a drive shaft that rotates integrally with the wheels is used. The internal sensor 3 may include an acceleration sensor and a yaw rate sensor.

[0019] The map database 4 is a database that stores map information. The map database 4 is formed, for example, in a storage device such as 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 includes information on the number of lanes on the road. The map information may include at least one of the following: position information where lanes increase or decrease, information on the presence or absence of a climbing lane, and information on the presence or absence of a yield lane on a one-lane road. The map database 4 may be formed in a server that can communicate with the vehicle.

[0020] The actuator 5 is a device used to control the vehicle. The actuator 5 includes at least a drive actuator, a brake actuator, and a steering actuator. The drive actuator controls the amount of air supplied to the engine (throttle opening) in response to a control signal from the ECU 10, thereby controlling the driving force of the vehicle. If the vehicle is a hybrid vehicle [HEV: Hybrid Electric Vehicle], in addition to the amount of air supplied to the engine, a control signal from the ECU 10 is input to a motor serving as a power source to control the driving force. If the vehicle is an electric vehicle [BEV: Battery Electric Vehicle], a control signal from the ECU 10 is input to a motor serving as a power source to control the driving force. In these cases, the motor serving as a power source constitutes the actuator 5.

[0021] The brake actuator controls a brake system in response to a control signal from the ECU 10, and controls the braking force applied to the wheels of the vehicle. For example, a hydraulic brake system can be used as the brake system. The steering actuator controls the drive of an assist motor that 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 vehicle.

[0022] The HMI 6 is an interface for inputting and outputting information between the ECU 10 and the occupant. The HMI 6 includes, for example, a display, a speaker, a microphone, and the like provided in the vehicle cabin. The HMI 6 outputs images from the display and sounds from the speaker in response to a control signal from the ECU 10. The display may function as a touch panel. The display may be a center display, a display for navigation, or a HUD [Head Up Display]. The HUD presents information to the occupant by projecting an image onto the windshield of the vehicle.

[0023] The HMI 6 presents information regarding the lane change proposal to the occupant. The information regarding the lane change proposal may be presented to the occupant by image output or audio output. The HMI 6 accepts an approval operation for the lane change proposal by the occupant who has received the proposal. The approval operation may be an operation of pressing a switch provided on the steering wheel or the like, a touch operation of an approval button image displayed on a touch panel, or a voice input indicating approval by the occupant via a microphone.

[0024] Next, a description will be given of the functional configuration of the ECU 10. The ECU 10 has a driving state recognition unit 11, a surrounding situation recognition unit 12, a map information acquisition unit 13, a driving route acquisition unit 14, a lane change suggestion unit 15, and a vehicle control unit 16.

[0025] The driving state recognition unit 11 may recognize the position of the vehicle on the map based on the position information of the GNSS receiving unit 1 and the map information of the map database 4. The driving state recognition unit 11 may recognize the position of the vehicle by SLAM [Simultaneous Localization and Mapping] technology using position information of fixed obstacles such as utility poles included in the map information of the map database 4 and the detection results of the external sensor 2. The driving state recognition unit 11 may recognize the position of the vehicle on the map by other well-known methods.

[0026] The running state recognition unit 11 recognizes the running state of the vehicle based on the detection result of the internal sensor 3. The running state includes the vehicle speed. The running state may include the vehicle acceleration and the vehicle yaw rate. The running state recognition unit 11 recognizes the vehicle speed based on the vehicle speed information of a vehicle speed sensor. The running state recognition unit 11 may recognize the vehicle acceleration based on the vehicle speed information of an acceleration sensor. The running state recognition unit 11 may recognize the direction of the vehicle based on the yaw rate information of a yaw rate sensor.

[0027] The surrounding situation recognition unit 12 recognizes the surrounding situation of the vehicle based on the detection result of the external sensor 2. The surrounding situation includes the traveling state of other vehicles around the vehicle. The surrounding situation includes the relative position, relative speed, and moving direction of objects such as other vehicles around the vehicle. The surrounding situation may include information on the type of object such as other vehicles, pedestrians, bicycles, etc. The surrounding situation may include information on lane lines recognized by publicly known white line recognition, etc. The surrounding situation may include signs and road shapes ahead of the vehicle. The surrounding situation may include the degree of congestion of other vehicles traveling around the vehicle.

[0028] The driving route acquisition unit 14 acquires the driving route along which the vehicle will travel, based on the driving state of the vehicle and the surrounding conditions. The driving route acquisition unit 14 may acquire the driving route along which the vehicle will travel, using the vehicle position information measured by the GNSS receiving unit 1 and the map information of the map database 4.

[0029] The driving route here corresponds to which lane the vehicle is traveling on on the road on which the vehicle is traveling. The driving route may be obtained from the dividing line recognized as the surrounding conditions and the number of lanes in the map information, which lane the vehicle is traveling on. The driving route may be obtained from information on a target route along a target route used in vehicle control such as automatic driving control. The target route is a route along which the vehicle travels under automatic driving control. The target route is set by automatic driving control, for example, based on a destination set by the occupant, vehicle position information, and map information.

[0030] The driving route is acquired, for example, in accordance with the number of lanes of the road at the position where the vehicle is currently traveling in the direction of extension of the road. Note that, for example, when a section of a one-lane road with a yield lane is the subject of a lane change proposal, the driving route may be acquired in accordance with the number of lanes of the road at a position a predetermined distance ahead of the current position of the vehicle in the direction of travel in the direction of extension of the road.

[0031] The lane change suggestion unit 15 suggests to the occupant of the host vehicle that the host vehicle should change lanes based on the surrounding conditions and the travel route. More specifically, when a lane mismatch condition is established based on the relative speed of another vehicle with respect to the host vehicle, which indicates that the selection of the lane in which the host vehicle is traveling is a mismatch in light of the surrounding conditions, the lane change suggestion unit 15 suggests to the occupant that the host vehicle should change lanes to a lane for slower vehicles than the lane in which the host vehicle is traveling. The lane change suggestion unit 15 controls the HMI 6 to present information related to the lane change suggestion to the occupant.

[0032] The selection of the lane in which the vehicle is traveling means a driver's or vehicle control's decision that the vehicle has reached the lane in which the vehicle is located among multiple lanes on the road in which the vehicle is currently traveling or will travel in the near future. In manual driving, the selection of the lane in which the vehicle is traveling corresponds to the vehicle reaching the position in response to the steering operation of the driver, who is an occupant. In automatic driving, the selection of the lane in which the vehicle is traveling may correspond to the selection of the lane as a target route along a target route of automatic driving control.

[0033] The lane mismatch condition is a condition that indicates that the lane selection in which the vehicle is traveling is a mismatch in light of the surrounding conditions. A mismatch in light of the surrounding conditions means, for example, a traffic flow in which the other vehicles around the vehicle are traveling at a faster speed than the vehicle traveling at the speed limit in a lane other than the lane that is scheduled to be traveled at the slowest speed among multiple lanes.

[0034] The lane mismatch condition is met when another vehicle traveling in the lane behind the host vehicle changes lanes into a lane for slow vehicles and overtakes the host vehicle, or when another vehicle traveling in the lane for slow vehicles behind the host vehicle overtakes the host vehicle, in succession for a predetermined number of other vehicles.

[0035] Fig. 2 is a schematic plan view for explaining a case where the lane mismatch condition is satisfied. In Fig. 2, on a road with three lanes on each side, a driving lane (lane) L1 in which the vehicle is expected to travel at the slowest speed, a driving lane (lane) L2 which is the second driving lane, and an overtaking lane (lane) L3 are arranged in this order from the left side in the traveling direction.

[0036] In the example of FIG. 2(a), the other vehicle V2 traveling in the lane L2 in which the host vehicle V1 is traveling behind the host vehicle V1 changes lanes to the lane L1 for low-speed vehicles and overtakes the host vehicle V1. The other vehicles V3 and V4 also overtake the host vehicle V1 in the same manner as the other vehicle V2. In this manner, the lane mismatch condition may be established when the other vehicle V2 traveling in the lane L2 in which the host vehicle V1 is traveling behind the host vehicle V1 changes lanes to the lane L1 for low-speed vehicles and overtakes the host vehicle V1 continuously for a predetermined number of other vehicles V2 to V4 (here, three vehicles). In the example of FIG. 2(a), the lane change suggestion unit 15 suggests to the occupant to change lanes to the lane L1 for low-speed vehicles compared to the lane L2 in which the host vehicle V1 is traveling.

[0037] In the example of FIG. 2(b), another vehicle V5 traveling in the lane L1 for low-speed vehicles behind the host vehicle V1 overtakes the host vehicle V1. The other vehicles V6 and V7 also overtake the host vehicle V1 in the same manner as the other vehicle V5. In this manner, the lane mismatch condition may be established when the other vehicle V5 traveling in the lane L1 for low-speed vehicles behind the host vehicle V1 overtakes the host vehicle V1 continuously for a predetermined number of other vehicles V2 to V4 (here, three vehicles). In the example of FIG. 2(b), the lane change suggestion unit 15 suggests to the occupant that the host vehicle V1 change lanes to the lane L1 for low-speed vehicles, which is different from the lane L2 in which the host vehicle V1 is traveling.

[0038] When the lane mismatch condition is satisfied, the lane change suggestion unit 15 may not suggest to the occupant that the vehicle should change lanes to a lane for slow vehicles if the surrounding conditions correspond to a predetermined suggestion cancellation condition. The suggestion cancellation condition means a condition in which the vehicle may disrupt traffic flow if it changes lanes, even if the lane mismatch condition is satisfied.

[0039] FIG. 3 is a schematic plan view for explaining a case where the surrounding situation corresponds to the proposal cancellation situation. In the example of FIG. 3(a), the other vehicle V2a traveling in the driving lane L5 in which the host vehicle V1 is traveling behind the host vehicle V1 changes lanes to the driving lane L4 for low-speed vehicles and passes the host vehicle V1 in succession for a predetermined number of other vehicles (here, three vehicles) V2a to V4a, and the lane mismatch condition is established. However, the driving lane L4 branches off from the driving lane L5 in front of the host vehicle V1. Here, if the direction of the driving lane L5 and the passing lane L6 is the target route of the host vehicle V1, when the host vehicle V1 changes lanes to the driving lane L4, it will immediately change lanes again to return to the driving lane L5, and the host vehicle V1 may disrupt the traffic flow. Therefore, when the driving lane L4 branches off from the driving lane L5 ahead of the vehicle V1, the lane change suggestion unit 15 does not suggest to the occupant that the vehicle change to the driving lane L4 for slower vehicles than the driving lane L5 in which the vehicle V1 is traveling.

[0040] In the example of FIG. 3(b), the situation is after a predetermined number (here, two) of other vehicles V5a, V6a, which were traveling in the driving lane L1a for low-speed vehicles, have continuously overtaken the host vehicle V1, and the lane mismatch condition is established. However, the driving lane L1a merges with the driving lane L2a ahead of the host vehicle V1. Here, if the host vehicle V1 changes lanes to the driving lane L1a, the host vehicle V1 will immediately change lanes again to return to the driving lane L2a, and the host vehicle V1 may disrupt the traffic flow. Therefore, when the driving lane L1a merges with the driving lane L2a ahead of the host vehicle V1, the lane change suggestion unit 15 does not suggest to the occupant to change lanes to the driving lane L1a for low-speed vehicles compared to the driving lane L2a in which the host vehicle V1 is traveling.

[0041] FIG. 4 is a schematic plan view for explaining a case where the surrounding situation corresponds to a proposal cancellation situation. In the example of FIG. 4(a), the situation is after a predetermined number (here, two) of other vehicles V5b, V6b, which were traveling in the driving lane L1b for low-speed vehicles, have continuously overtaken the host vehicle V1, and the lane mismatch condition is established. However, lane regulation due to road construction or the like is performed in the driving lane L1b in front of the host vehicle V1. Here, if the host vehicle V1 changes lanes to the driving lane L1b, the host vehicle V1 will immediately change lanes again to return to the driving lane L2b, and there is a risk that the host vehicle V1 will disrupt the traffic flow. Therefore, when lane regulation due to road construction or the like is performed in the driving lane L1b in front of the host vehicle V1, the lane change suggestion unit 15 does not suggest to the occupant that the host vehicle V1 change lanes to the driving lane L1b for low-speed vehicles compared to the driving lane L2b in which the host vehicle V1 is traveling.

[0042] In the example of FIG. 4(b), the situation is after a predetermined number (here, two) of other vehicles V5c, V6c, which were traveling in the driving lane L1c for low-speed vehicles, have continuously overtaken the host vehicle V1, and the lane mismatch condition is established. However, there is a fallen object in the driving lane L1c ahead of the host vehicle V1. In this case, if the host vehicle V1 changes lanes to the driving lane L1c, it will immediately change lanes again to return to the driving lane L2c, and the host vehicle V1 may disrupt the traffic flow. Therefore, when there is a fallen object in the driving lane L1c ahead of the host vehicle V1, the lane change suggestion unit 15 does not suggest to the occupant to change lanes to the driving lane L1c for low-speed vehicles compared to the driving lane L2c in which the host vehicle V1 is traveling.

[0043] FIG. 5(a) is a schematic plan view for explaining a case where the surrounding situation corresponds to the proposal cancellation situation. In the example of FIG. 5(a), the road is a steep uphill slope, and the situation is after a predetermined number (here, two) of other vehicles V5d, V6d, which are traveling on the climbing lane L1d for low-speed vehicles, have continuously overtaken the host vehicle V1, and the lane mismatch condition is established. However, in front of the host vehicle V1, a trailer V8 loaded with heavy goods is climbing at an extremely low speed on the climbing lane L1d. Here, if the host vehicle V1 changes lanes to the climbing lane L1d, it will immediately change lanes again to return to the driving lane L2d, and the host vehicle V1 may disrupt the traffic flow. Therefore, when a trailer V8 loaded with heavy loads is climbing the climbing lane L1d in front of the host vehicle V1 at an extremely slow speed, the lane change suggestion unit 15 does not suggest to the occupant that the vehicle change to the climbing lane L1d for slower vehicles than the driving lane L2d in which the host vehicle V1 is traveling.

[0044] FIG. 5(b) is a schematic plan view for explaining a case where the lane mismatch condition is satisfied. In FIG. 5(b), the host vehicle V1 basically travels on a one-lane road where the host vehicle lane L7 and the oncoming lane L8 face each other. A yield lane L9 for low-speed vehicles is provided in the host vehicle lane L7 ahead of the host vehicle V1. Behind the host vehicle V1, another vehicle V9 traveling in the host vehicle lane L7 catches up with the host vehicle V1. In this situation, although the host vehicle V1 is currently located on a one-lane road, there is room for smoothing the traffic flow because the host vehicle V1 may obstruct the traffic flow. Therefore, the driving assistance device 100 proposes to the occupant to change lanes to the yield lane L9 for low-speed vehicles by setting the section of the yield lane L9 on the one-lane road as a target for the lane change proposal. The travel route acquisition unit 14 may acquire the travel route in accordance with the number of lanes of the road at a position where a yield lane L9 exists a predetermined distance ahead of the current position of the host vehicle V1 in the direction of travel of the road. The lane mismatch condition may be satisfied, for example, when the relative speed of the other vehicle V9 traveling in the host vehicle lane L7 when the other vehicle V9 catches up with the host vehicle V1 is equal to or greater than a predetermined value, and there are a predetermined number of vehicles following the other vehicle V9. When this lane mismatch condition is satisfied, the lane change suggestion unit 15 suggests to the occupant to change lanes to the yield lane L9 for low-speed vehicles compared to the travel lane L7 in which the host vehicle V1 is traveling.

[0045] The vehicle control unit 16 may execute automatic lane change control depending on whether or not the occupant has approved the proposal made by the lane change proposing unit 15. The vehicle control unit 16 may execute automatic lane change control of the vehicle by transmitting a control signal to the actuator 5.

[0046] [Operation of driving support device] Next, the operation of the driving support device 100 will be described with reference to the drawings. Figure 6 is a flowchart showing an example of the processing of the ECU in Figure 1. The processing of the ECU is executed, for example, while the automatic driving control of the vehicle is being executed.

[0047] As shown in FIG. 6, in step S11, the ECU 10 of the driving assistance device 100 acquires the vehicle position, map information, driving state, surrounding conditions, and driving route using the driving state recognition unit 11, the surrounding conditions recognition unit 12, the map information acquisition unit 13, and the driving route acquisition unit 14.

[0048] In step S12, the ECU 10 determines whether or not a lane for low-speed vehicles exists, using the lane change suggestion unit 15. The ECU 10 may determine whether or not a lane for low-speed vehicles exists a predetermined distance ahead of the current position of the host vehicle along the traveling direction in the extension direction of the road, as shown in FIG.

[0049] If the lane change suggestion unit 15 determines that a lane for slow vehicles exists (S12: YES), the ECU 10 proceeds to step S13. If the lane change suggestion unit 15 determines that a lane for slow vehicles does not exist (S12: NO), the ECU 10 ends the current process in Fig. 6. After that, the ECU 10 repeats the process from S11 again after a certain period of time has elapsed.

[0050] In step S13, the ECU 10 determines whether or not the lane mismatch condition is satisfied by the lane change suggestion unit 15. If the lane change suggestion unit 15 determines that the lane mismatch condition is satisfied (S13: YES), the ECU 10 proceeds to step S14. If the lane change suggestion unit 15 determines that the lane mismatch condition is not satisfied (S13: NO), the ECU 10 ends the current process of FIG. 6. After that, the ECU 10 repeats the process from S11 again after a certain time has elapsed.

[0051] In step S14, the ECU 10 determines whether the surrounding situation does not correspond to the proposal cancellation situation by the lane change proposing unit 15. If the lane change proposing unit 15 determines that the surrounding situation does not correspond to the proposal cancellation situation (S14: YES), the ECU 10 proceeds to step S15. If the lane change proposing unit 15 determines that the surrounding situation corresponds to the proposal cancellation situation (S14: NO), the ECU 10 ends the current process of FIG. 6. After that, the ECU 10 repeats the process from S11 again after a certain time has elapsed.

[0052] In step S15, the ECU 10 proposes a lane change to the occupant of the host vehicle by the lane change suggestion unit 15. The lane change suggestion unit 15 proposes a lane change to the occupant of the host vehicle by using the HMI 6, for example.

[0053] In step S16, the ECU 10 judges whether or not the lane change proposing unit 15 has performed an approval operation for the proposal. If the lane change proposing unit 15 judges that the occupant of the host vehicle has performed an approval operation for the lane change proposal to the occupant of the host vehicle (S16: YES), the ECU 10 proceeds to step S17. If the lane change proposing unit 15 judges that the occupant of the host vehicle has not performed an approval operation for the lane change proposal to the occupant of the host vehicle (S16: NO), the ECU 10 ends the current process of FIG. 6. After that, the ECU 10 repeats the process from S11 again after a certain time has elapsed.

[0054] In step S17, the ECU 10 executes a lane change by the vehicle control unit 16. The vehicle control unit 16 performs automatic lane change control of the vehicle by, for example, transmitting a control signal to the actuator 5. After that, the ECU 10 repeats the process from S11 again after a certain time has elapsed.

[0055] According to the driving assistance device 100 described above, when a lane mismatch condition is established, which indicates that the selection of the lane in which the vehicle is traveling is a mismatch in light of the surrounding conditions, the lane change suggestion unit 15 suggests to the occupant that the vehicle change to a lane for slow vehicles compared to the lane in which the vehicle is traveling. For example, when the occupant accepts the suggestion, the lane change to a lane for slow vehicles is performed, and the mismatch in the selection of the lane in which the vehicle is traveling is resolved. This makes it possible to resolve a situation in which the vehicle may obstruct traffic flow, and to facilitate smooth traffic flow.

[0056] In the driving assistance device 100, the lane mismatch condition is satisfied when another vehicle traveling in the lane behind the host vehicle changes lanes to a lane for slow vehicles and overtakes the host vehicle, or another vehicle traveling in the lane for slow vehicles behind the host vehicle overtakes the host vehicle, in succession for a predetermined number of other vehicles. In this way, by satisfying the lane mismatch condition when the host vehicle is overtaken or passed by another vehicle by a certain number of times, it is possible to exclude the host vehicle from being subject to a lane change proposal even if the host vehicle is overtaken or passed by, for example, one other vehicle that is extremely faster than the host vehicle.

[0057] In the driving support device 100, when the lane mismatch condition is satisfied, the lane change suggestion unit 15 does not suggest to the occupant that the vehicle should change lanes to a lane for low-speed vehicles if the surrounding situation recognition unit 12 corresponds to a predetermined situation where the suggestion is cancelled. As a result, when the surrounding situation corresponds to a predetermined situation where the suggestion is cancelled, the vehicle may be less likely to obstruct traffic flow if the vehicle does not change lanes. Therefore, it is possible to smooth the traffic flow according to the surrounding situation.

[0058] Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments. The present disclosure can be implemented in various forms including the above-described embodiments and various modifications and improvements based on the knowledge of those skilled in the art.

[0059] In the above embodiment, the driving assistance device 100 is a part of an automatic driving device that executes automatic driving control, but automatic driving control is not essential. The driving assistance device 100 may be capable of executing automatic lane change control, but automatic lane change control is not essential. Even during manual driving, the driving assistance device 100 may at least suggest to the occupant to change lanes to a lane for slow vehicles compared to the lane in which the host vehicle is traveling when a lane mismatch condition is established.

[0060] In the above embodiment, as shown in Figs. 2 to 5, lane mismatch conditions and proposal cancellation situations are exemplified, but the lane mismatch conditions and proposal cancellation situations are not limited to these examples. [Explanation of symbols]

[0061] 12: surrounding situation recognition unit, 14: driving route acquisition unit, 15: lane change suggestion unit, 100: driving assistance device, L1, L2: driving lane (lane), L3: overtaking lane (lane), V1: host vehicle.

Claims

1. A surrounding situation recognition unit that recognizes surrounding situations including driving states of other vehicles around the host vehicle; a travel route acquisition unit that acquires a travel route along which the host vehicle travels based on a travel state of the host vehicle and the surrounding conditions; a lane change suggestion unit that suggests to an occupant of the vehicle a lane change of the vehicle based on the surrounding conditions and the travel route, The lane change suggestion unit is a driving assistance device that suggests to the occupant that the vehicle change to a lane for slower vehicles than the lane in which the vehicle is traveling when a lane mismatch condition is established, which indicates that the selection of the lane in which the vehicle is traveling is a mismatch in light of the surrounding conditions, based on the relative speed of the other vehicle with respect to the vehicle.

2. 2. The driving assistance device according to claim 1, wherein the lane mismatch condition is met when the other vehicle traveling in the lane in which the host vehicle is traveling behind the host vehicle changes lanes into the lane for slow vehicles and overtakes the host vehicle, or when the other vehicle traveling in the lane for slow vehicles behind the host vehicle overtakes the host vehicle, for a predetermined number of the other vehicles, in succession.

3. 3. The driving assistance device according to claim 1, wherein when the lane mismatch condition is satisfied and the surrounding conditions correspond to a predetermined suggestion cancellation condition, the lane change suggestion unit does not suggest to the occupant that the vehicle should change to the lane for low-speed vehicles.

Images