Autonomous driving control device and autonomous driving control method

Abstract

According to the present invention, an autonomous driving ECU functions as an autonomous driving control device for controlling traveling of an own vehicle (Am) by an autonomous driving function. The autonomous driving ECU recognizes an emergency vehicle (Ae) approaching the own vehicle (Am). When approaching of the emergency vehicle (Ae) is recognized in a state in which the own vehicle (Am) is located in an intersection area (IA), the autonomous driving ECU controls behavior of the own vehicle (Am) in order to yield the way to the emergency vehicle (Ae) in the intersection area (IA).

Description

Automatic driving control device and automatic driving control method CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Patent Application No. 2024-100646 filed in Japan on June 21, 2024, the contents of which are incorporated by reference in their entirety.

[0002] The disclosure of this specification relates to an automatic driving technology for controlling the driving of a vehicle.

[0003] Patent Document 1 discloses a blind spot vehicle sound detection system that can detect the direction of another vehicle that is in the blind spot of an obstruction.

[0004] JP 2012-146149 A

[0005] The inventors of the present disclosure have conceived of utilizing the other vehicle detection technology described in Patent Document 1 to recognize emergency vehicles. Responding to emergency vehicles can be a challenge for autonomous vehicles that operate using autonomous driving functions. Particularly when an autonomous vehicle encounters an emergency vehicle at an intersection where other vehicles are present around the vehicle, the autonomous vehicle may become an obstacle to the other vehicles and the emergency vehicle.

[0006] The present disclosure aims to provide an automatic driving control device and an automatic driving control method that are less likely to have a negative impact on the surrounding area even when encountering an emergency vehicle in an intersection area.

[0007] In order to achieve the above object, one disclosed aspect is an automatic driving control device that controls the driving of a vehicle using an automatic driving function, and is equipped with an outside recognition unit that recognizes emergency vehicles approaching the vehicle, and a behavior control unit that controls the behavior of the vehicle in the intersection area to give way to the emergency vehicle when the approach of an emergency vehicle is recognized while the vehicle is located in an intersection area.

[0008] Another disclosed aspect is an autonomous driving control method for controlling the driving of a vehicle using an autonomous driving function, which includes, in processing performed by at least one processing unit, a step of recognizing an emergency vehicle approaching the vehicle, and, if the approach of an emergency vehicle is recognized while the vehicle is located in an intersection area, controlling the behavior of the vehicle to give way to the emergency vehicle in the intersection area.

[0009] In these aspects, when the host vehicle is located in an intersection area and detects the approach of an emergency vehicle, the behavior of the host vehicle is controlled to yield to the emergency vehicle at the intersection area. Therefore, the host vehicle is less likely to interfere with other vehicles and emergency vehicles present in the intersection area. As a result, even if the host vehicle encounters an emergency vehicle at an intersection area where other vehicles are present, the host vehicle is less likely to have a negative impact on the surrounding area.

[0010] It should be noted that the reference numbers in parentheses in the claims merely indicate an example of the correspondence with the specific configurations in the embodiments described below, and do not limit the technical scope in any way. Furthermore, claims not explicitly stated in the claims may be combined together if no particular problems arise in the combination.

[0011] FIG. 1 is a diagram showing an overall view of an in-vehicle system including an autonomous driving ECU according to a first embodiment of the present disclosure. FIG. 2 is a block diagram showing details of the autonomous driving ECU together with related configurations. FIG. 3 is a diagram for explaining behavior control in scene 1. FIG. 4 is a diagram for explaining behavior control in scene 2. FIG. 5 is a diagram for explaining behavior control in scene 3. FIG. 6 is a diagram for explaining behavior control in scene 4. FIG. 7 is a diagram for explaining behavior control in scene 5. FIG. 8 is a diagram for explaining behavior control in scene 6. FIG. 9 is a flowchart showing details of behavior control processing executed by the autonomous driving ECU before entering an intersection area. FIG. 10 is a flowchart showing details of behavior control processing executed after entering an intersection area. FIG. 11 is a flowchart showing details of behavior control processing of a second embodiment.

[0012] Hereinafter, several embodiments will be described with reference to the drawings. Note that corresponding components in each embodiment are given the same reference numerals, and redundant description may be omitted. When only a portion of the configuration is described in each embodiment, the configuration of another embodiment described previously can be applied to the remaining portion of the configuration. Furthermore, in addition to the combinations of configurations explicitly stated in the description of each embodiment, configurations of several embodiments can also be partially combined together even if not explicitly stated, as long as there is no particular problem with the combination.

[0013] First Embodiment The functions of an autonomous driving control device according to a first embodiment of the present disclosure are realized by an autonomous driving ECU (Electronic Control Unit) 50 shown in FIG. 1 . The autonomous driving ECU 50 is mounted on a vehicle (hereinafter, host vehicle Am). By mounting the autonomous driving ECU 50, the host vehicle Am becomes an autonomous driving vehicle or an autonomously driven vehicle equipped with an autonomous driving function, and is capable of driving using the autonomous driving function. The autonomous driving level in this disclosure is based on the standards defined by the Society of Automotive Engineers. In this disclosure, autonomous driving control of autonomous driving level 3 or higher by the autonomous driving ECU 50 is referred to as "autonomous driving control."

[0014] During an autonomous driving period in which the host vehicle Am is driven by autonomous driving control by the autonomous driving ECU 50, the driver may be permitted to perform a specific action other than predefined driving (hereinafter referred to as a second task). During an autonomous driving period under autonomous driving level 3, the driver is legally permitted to perform the second task until a request for a driver handover is made by the autonomous driving ECU 50 in cooperation with the HMI (Human Machine Interface) control device 100. For example, actions such as watching entertainment content such as videos, operating a device such as a smartphone, and eating are considered as second tasks.

[0015] The autonomous driving ECU 50 is connected to a communication line 99 of an in-vehicle LAN (Local Area Network) for constructing the in-vehicle system 1. The in-vehicle LAN is constructed using communication protocols such as CAN (Controller Area Network, registered trademark) and Ethernet (registered trademark). The communication line 99 is connected to the periphery monitoring sensor 30, the locator 35, the navigation ECU 38, the in-vehicle communication device 39, the cruise control ECU 40, and the HMI control device 100. These nodes connected to the communication line 99 can communicate with each other. Certain nodes among these ECUs, etc. may be electrically connected directly to each other and be able to communicate without going through the communication line 99.

[0016] The perimeter monitoring sensor 30 is an autonomous sensor mounted on the host vehicle Am and monitors the environment surrounding the host vehicle Am. The perimeter monitoring sensor 30 is capable of detecting moving objects and stationary objects within a detection range around the host vehicle. The perimeter monitoring sensor 30 provides detection information of objects around the host vehicle to the autonomous driving ECU 50, etc. The perimeter monitoring sensor 30 includes a camera unit 31 and an exterior acoustic sensor 32. The perimeter monitoring sensor 30 may further include a millimeter-wave radar, a lidar, a sonar, etc.

[0017] The camera unit 31 includes a front camera module, a rear camera module, and front, rear, left, and right surround view camera modules. The camera unit 31 includes multiple camera modules, enabling it to capture images of the entire surroundings of the vehicle Am. The camera unit 31 outputs image data captured by each camera module or analysis information of the image data as detection information to the communication line 99.

[0018] The exterior acoustic sensor 32 is primarily composed of a microphone element that converts sound into an electrical signal. The microphone element functions as a condenser microphone that outputs an electrical signal based on changes in capacitance caused by vibration of a thin diaphragm due to sound pressure. A MEMS (Micro Electro Mechanical Systems) microphone or the like can be used as the microphone element. Alternatively, the exterior acoustic sensor 32 may be a piezoelectric microphone configuration using a piezoelectric sensor instead of a condenser microphone. The piezoelectric sensor converts sound into an electronic signal using the piezoelectric element. The exterior acoustic sensor 32 is held on the exterior structure of the host vehicle Am with the sound collection surface of the microphone element or the like facing the exterior structure. Multiple exterior acoustic sensors 32 are provided on the front, rear, left and right sides, ceiling, etc. of the host vehicle Am. The exterior acoustic sensors 32 provided at each location can detect incoming sounds from all around the host vehicle Am. The exterior acoustic sensor 32 outputs the sound data generated by each microphone element or analysis information of the sound data as detection information to the communication line 99 .

[0019] The locator 35 includes a GNSS (Global Navigation Satellite System) receiver, an inertial sensor, etc. The locator 35 sequentially determines the position and traveling direction of the host vehicle Am by combining positioning signals received from multiple positioning satellites by the GNSS receiver, measurement results from the inertial sensor, and vehicle speed information output to the communication line 99. The locator 35 sequentially outputs position information and direction information of the host vehicle Am based on the positioning results to the communication line 99 as locator information.

[0020] The locator 35 also has a map database that stores map data. The map database is primarily composed of a large-capacity storage medium that stores a large amount of three-dimensional map data and two-dimensional map data. The three-dimensional map data is a so-called HD (High Definition) map and includes road information necessary for autonomous driving. Specifically, the three-dimensional map data includes three-dimensional road shape information and detailed information about each lane. The locator 35 can update the three-dimensional map data and two-dimensional map data to the latest information through external communication via the on-board communication device 39. The locator 35 reads map data around the current location from the map database and provides it to the autonomous driving ECU 50, etc., along with locator information.

[0021] The navigation ECU 38 acquires information about a destination specified by a passenger such as a driver based on operation information acquired from the HMI control device 100. The navigation ECU 38 acquires vehicle position information and direction information from the locator 35, and sets a route from the current position to the destination. The navigation ECU 38 provides route information indicating the set route to the destination to the autonomous driving ECU 50, the HMI control device 100, etc. The navigation ECU 38 works in conjunction with the HMI system 10 (described later) to provide route guidance to the destination by combining screen displays and voice messages, etc., and notifying the driver of the direction of travel of the vehicle Am at intersections, branching points, etc.

[0022] Here, a user terminal such as a smartphone or tablet may be connected to the communication line 99 or the HMI control device 100. Such a user terminal may provide the autonomous driving ECU 50 with information such as vehicle position information, direction information, and map data in place of the locator 35. Furthermore, the user terminal may provide the autonomous driving ECU 50 and the HMI control device 100 with information such as route information to a destination in place of the navigation ECU 38. Furthermore, the user terminal may play video content in place of the HMI system 10 described below or together with the HMI system 10.

[0023] The in-vehicle communication device 39 is an external communication unit mounted on the host vehicle Am. The in-vehicle communication device 39 functions as a V2X (Vehicle to Everything) communication device. The in-vehicle communication device 39 transmits and receives information via wireless communication with a roadside device installed on the side of the road. As an example, the in-vehicle communication device 39 receives congestion information, traffic regulation information, and the like from the roadside device. The congestion information and traffic regulation information are, for example, VICS (registered trademark) information. The in-vehicle communication device 39 may further receive, from the roadside device, signal information indicating the lighting pattern of a traffic signal TL (see FIG. 3 ), as well as detection information of stopped vehicles, parked vehicles, pedestrians, cyclists, and the like. The in-vehicle communication device 39 provides the received congestion information, traffic regulation information, signal information, detection information, and the like to the navigation ECU 38, the autonomous driving ECU 50, the HMI control device 100, and the like.

[0024] The cruise control ECU 40 is an electronic control device that mainly includes a microcontroller. The cruise control ECU 40 generates vehicle speed information indicating the current traveling speed of the host vehicle Am based on detection signals from wheel speed sensors provided at the hub portions of each wheel, and sequentially outputs the generated vehicle speed information to a communication line 99. The cruise control ECU 40 has at least the functions of a brake control ECU, a drive control ECU, and a steering control ECU. The cruise control ECU 40 continuously controls the braking force of each wheel, the output of the powertrain, and the steering angle based on either an operation command based on the driver's driving operation or a control command from the automatic driving ECU 50.

[0025] The HMI control device 100, together with a plurality of display devices, an audio device 24, an ambient light 25, an operation device 26, etc., constitutes an HMI system 10. The HMI system 10 has an input interface function that accepts operations by a passenger such as a driver of the vehicle Am, and an output interface function that presents information to the driver.

[0026] The display devices present information to the driver's vision by displaying images, etc. The display devices include a meter display 21, a center information display (hereinafter referred to as CID) 22, and a head-up display (hereinafter referred to as HUD) 23. The CID 22 has a touch panel function and detects touch operations on the display screen by the driver, etc.

[0027] The audio device 24 has multiple speakers installed in the vehicle cabin. The audio device 24 reproduces, for example, notification sounds or voice messages through the speakers. The ambient lights 25 are provided on the instrument panel, center console, steering wheel, door trim, etc. The ambient lights 25 present information to the driver's peripheral vision through ambient displays that change the emitted light color.

[0028] The operation device 26 is an input unit that accepts user operations by the driver, etc. User operations related to activation and deactivation of the autonomous driving function, user operations related to setting a destination for route guidance, user operations related to setting air conditioning, etc. The operation device 26 includes a steering switch provided on the spokes of the steering wheel, an operation lever provided on the steering column, and a voice input device that recognizes what the passengers are saying.

[0029] The HMI control device 100 is a computer that mainly includes a control circuit equipped with a processing unit 11, a RAM 12, a storage unit 13, an input / output interface 14, and a bus connecting these. The HMI control device 100 functions as a presentation control device and comprehensively controls the presentation of information using a plurality of display devices, an audio device 24, an ambient light 25, etc. The HMI control device 100 presents information related to autonomous driving in cooperation with the autonomous driving ECU 50. For example, when the autonomous driving ECU 50 plans to end autonomous driving control, the HMI control device 100 issues a notification to the driver requesting that he or she take over driving.

[0030] The HMI control device 100 acquires operation information indicating the content of user operations from the CID 22, the operation device 26, etc. The HMI control device 100 provides operation information of user operations related to the autonomous driving function, etc. to the autonomous driving ECU 50. The HMI control device 100 also provides operation information of a user operation for setting a destination of the host vehicle Am to the navigation ECU 38.

[0031] 1 and 2 is a computer that mainly includes a processing unit 51, a RAM 52, a storage unit 53, an input / output interface 54, and a control circuit that includes a bus connecting these components. The processing unit 51 accesses the RAM 52 to execute various processes (instructions) for implementing the autonomous driving control method according to the present disclosure. The storage unit 53 stores various programs (e.g., autonomous driving control programs) that are executed by the processing unit 51. As the processing unit 51 executes the programs, the autonomous driving ECU 50 is configured with an information linkage unit 61, an environment recognition unit 62, a behavior determination unit 63, a control execution unit 64, and the like as functional units for implementing the autonomous driving function.

[0032] The information linking unit 61 enables information linking between the navigation ECU 38, the in-vehicle communication device 39, the HMI control device 100, etc. and the autonomous driving ECU 50. The information linking unit 61 acquires route information from the navigation ECU 38 and provides the acquired route information to the environment recognition unit 62 and the action determination unit 63. The information linking unit 61 requests the navigation ECU 38 to change (reset) the destination or the planned driving route by outputting a reroute request to the navigation ECU 38. The information linking unit 61 provides signal information and detection information received by the in-vehicle communication device 39 to the environment recognition unit 62.

[0033] The information linking unit 61 outputs a request to the HMI control device 100 to make an in-vehicle notification, thereby enabling the HMI control device 100 to make a notification synchronized with the operating state of the autonomous driving function. Specifically, the information linking unit 61 outputs a request to make various notifications related to the approach of an emergency vehicle Ae (see FIG. 3 ) to the HMI control device 100. The information linking unit 61 links with the HMI control device 100 to make an emergency vehicle approach notification, etc. The emergency vehicle approach notification is a notification that shows approach notification information related to the approach of the emergency vehicle Ae to passengers such as the driver and passengers. In the emergency vehicle approach notification, the presence of the emergency vehicle Ae approaching the host vehicle Am is notified to the passengers using a display on a display device and a sound from the audio device 24, etc.

[0034] The environment recognition unit 62 recognizes the driving environment of the host vehicle Am by combining the locator information and map data acquired from the locator 35, the detection information acquired from the perimeter monitoring sensor 30, and the vehicle speed information acquired from the communication line 99. The environment recognition unit 62 may acquire the detection information received by the on-board communication device 39 from the information linkage unit 61 and use it for recognition of the driving environment. The environment recognition unit 62 acquires road information related to the road on which the host vehicle Am is traveling or the road on which the host vehicle Am is scheduled to travel, and grasps the size, type, relative position, relative speed, etc. of dynamic targets present around the host vehicle Am, such as other vehicles traveling around the host vehicle Am. The environment recognition unit 62 sequentially provides the action determination unit 63 with the recognition results of the driving environment, including the road information and the grasped information of the dynamic targets.

[0035] The environment recognition unit 62 grasps approaching sounds around the host vehicle Am. The environment recognition unit 62 detects an emergency vehicle Ae approaching the host vehicle Am by combining detection information based on image data from the camera unit 31 with detection information based on sound data collected by the exterior acoustic sensor 32. The environment recognition unit 62 may be capable of detecting the approach of an emergency vehicle Ae to the host vehicle Am by character recognition of messages such as "emergency vehicle approaching" displayed on electronic signs, traffic information boards, etc., based on the image data. The environment recognition unit 62 detects police vehicles, fire engines, ambulances, etc., as emergency vehicles Ae. Unless otherwise specified, the emergency vehicle Ae in the present disclosure refers to an emergency vehicle Ae traveling for emergency purposes.

[0036] By using the sound data, the environment recognition unit 62 can recognize the approach of an emergency vehicle Ae sounding a siren earlier than when using only image data. The environment recognition unit 62 uses the sound data to identify the type of siren being sounded by the emergency vehicle Ae. The environment recognition unit 62 determines the tone of the siren, the length of each siren sound, and whether or not a warning bell is sounding. Based on the determined siren type, the environment recognition unit 62 determines the type and emergency status of the emergency vehicle Ae approaching the vehicle Am. Additionally, the environment recognition unit 62 detects, based on the sound data, an appeal sound SoA (see FIG. 3 ) emitted by the emergency vehicle Ae in relation to the intersection area IA. The appeal sound SoA is a sound indicating that the emergency vehicle Ae is entering the intersection area IA and is a sound intended to alert vehicles traveling around the emergency vehicle Ae to the presence of the emergency vehicle Ae. The appeal sound SoA includes an emphasized siren sound emitted when the emergency vehicle Ae enters the intersection area IA, an announcement sound emitted by the emergency vehicle Ae, and the like.

[0037] When the environment recognition unit 62 recognizes an emergency vehicle Ae approaching the host vehicle Am, it detects the relative position and movement direction of the emergency vehicle Ae. As a result, the environment recognition unit 62 determines whether the recognized emergency vehicle Ae is approaching the host vehicle Am from the front, the rear, or the side. The environment recognition unit 62 further recognizes the operating state of the turn indicators (winkers) of the emergency vehicle Ae, the vehicle direction of the emergency vehicle Ae, etc., based on the image capture data.

[0038] When the autonomous driving ECU 50 has control of the driving operation, the behavior determination unit 63 generates a planned driving line for the host vehicle Am to travel on, based on the route information provided by the information linkage unit 61 and the recognition result of the driving environment by the environment recognition unit 62. The behavior determination unit 63 outputs the generated planned driving line to the control execution unit 64.

[0039] The behavior determination unit 63 cooperates with the cruise control ECU 40 to switch the control state of the host vehicle Am between automatic driving and manual driving. In addition, the behavior determination unit 63 switches the automation level of the cruise control (automatic driving control) performed by the automatic driving function. For example, when the information linkage unit 61 detects an input of an operation to transition to level 3 or level 4, the behavior determination unit 63 raises the automation level of the cruise control from manual driving or driving assistance control of level 2 or lower to autonomous cruise control of level 3 or higher. When the behavior determination unit 63 determines to end the autonomous cruise control, it lowers the automation level of the cruise control from autonomous cruise control to driving assistance control or manual driving.

[0040] When the autonomous driving ECU 50 has control of driving operations, the control execution unit 64 cooperates with the cruise control ECU 40 to execute acceleration / deceleration control, steering control, and the like of the host vehicle Am in accordance with the planned driving line generated by the action determination unit 63. Specifically, the control execution unit 64 generates control commands based on the planned driving line and sequentially outputs the generated control commands to the cruise control ECU 40.

[0041] [Behavior control for responding to emergency vehicles at intersections] The autonomous driving ECU 50 described above can avoid an emergency vehicle Ae approaching the host vehicle Am when executing driving assistance control for autonomous driving level 2 or autonomous driving control for autonomous driving level 3 or higher. In particular, when the approach of the emergency vehicle Ae is recognized while the host vehicle Am is located in an intersection area IA, the behavior determination unit 63 controls the behavior of the host vehicle Am to give way to the emergency vehicle Ae at the intersection area IA.

[0042] Below, details of the behavioral control implemented in scenes 1 to 6 in which the approach of an emergency vehicle Ae is detected at or near an intersection IS will be described based on Figures 3 to 8 and with reference to Figures 1 and 2. The intersection area IA is the area surrounded by the stop lines SL of each connecting road connected to the intersection IS. The crosswalks of each connecting road are located within the intersection area IA. Furthermore, the intersection IS at which the behavioral control of the present disclosure is implemented is not limited to the crossroads shown in Figures 3 to 8, but may also be a multi-junction (e.g., a six-way intersection), a Y-junction, a T-junction, a roundabout, or the like.

[0043] <Scene 1: Response to an Emergency Vehicle Ahead That Is Emitting an Alert Sound> In scene 1 shown in FIG. 3 , the host vehicle Am is stopped within the intersection area IA to wait to turn right. There are other vehicles Ao waiting to turn right in front and behind the host vehicle Am. The emergency vehicle Ae is traveling in the oncoming lane Lo located in front of the host vehicle and enters the intersection area IA from the connecting road in front of the host vehicle. The emergency vehicle Ae plans to proceed straight through the intersection IS. To avoid the other vehicle Ao that has pulled over to the shoulder, the emergency vehicle Ae is traveling from the straight lane Lt into the right-turn lane Lr. The emergency vehicle Ae approaches the intersection area IA while emitting an alert sound SoA to notify those around it of the presence of the vehicle. The emergency vehicle Ae enters the intersection area IA after successively sounding an appeal sound SoA, such as an emphasized siren sound that is more emphasized than a normal siren sound, and a standard announcement sound such as "An emergency vehicle is passing."

[0044] The environment recognition unit 62 detects the presence of an emergency vehicle Ae approaching the host vehicle Am based on the sound data, and then identifies the relative position and movement direction of the emergency vehicle Ae. When the host vehicle Am is located within the intersection area IA, the environment recognition unit 62 estimates whether the approaching emergency vehicle Ae is planning to enter the intersection area IA where the host vehicle Am is located. When the environment recognition unit 62 estimates that the emergency vehicle Ae is planning to enter the intersection area IA, it detects whether the emergency vehicle Ae is emitting an appeal sound SoA based on the sound data.

[0045] The environment recognition unit 62 continuously grasps the lighting pattern of the traffic signal TL located in front of the vehicle Am, in other words, the traffic signal TL that the vehicle Am must follow, based on the image data and signal information. In scene 1, after detecting the emergency vehicle Ae, the environment recognition unit 62 recognizes that the lighting pattern of the traffic signal TL in front of the vehicle Am is a lighting pattern that allows the vehicle Am to proceed (progress permitted state, hereinafter referred to as a green light).

[0046] The behavior determination unit 63 estimates a passing line PLe (see the dotted strip area in FIG. 3 ) of the emergency vehicle Ae in the intersection area IA based on information about the emergency vehicle Ae grasped by the environment recognition unit 62. The behavior determination unit 63 estimates the passing line PLe based on the operating state of the turn signal of the emergency vehicle Ae, the vehicle direction of the emergency vehicle Ae, etc. The behavior determination unit 63 may use information about external objects (other vehicles Ao, pedestrians, etc.) recognized by the environment recognition unit 62 to estimate the passing line PLe.

[0047] The behavior determination unit 63 performs handover control when the host vehicle Am is located on the passing line PLe within the intersection area IA and the environment recognition unit 62 detects the appeal sound SoA. By performing the handover control, the behavior determination unit 63 transfers at least a portion of the control of the host vehicle Am from the autonomous driving function to the driver. In other words, the behavior determination unit 63 determines to lower the automation level of the driving control based on the detection of the appeal sound SoA. The behavior determination unit 63 may determine to switch from autonomous driving control to manual driving, or may determine that the driver should start monitoring the surroundings (eyes on) or start holding the steering wheel (hands on). The more complex the traffic situation in the intersection area IA, the more authority the behavior determination unit 63 hands over to the driver.

[0048] The information linking unit 61 outputs a request to implement an emergency vehicle approach notification to the HMI control device 100 based on the detection of an emergency vehicle Ae by the environment recognition unit 62. The information linking unit 61 outputs a request to implement a driving change request to the HMI control device 100 based on the determination of the control right transfer by the action determination unit 63. The content of the driving change request is changed depending on the content of the control right transferred to the driver.

[0049] As an example, when the behavior determination unit 63 determines to completely switch over to manual driving and all driving control by the automatic driving function is stopped, the HMI control device 100 requests the driver to start all driving operations. In this case, the driver who has acquired control responds to the approaching emergency vehicle Ae at his / her own discretion. For example, the driver who starts driving operations in scene 1 checks the left rear side, switches the left turn signal to flashing, and moves the host vehicle Am to the left.

[0050] As another example, when only a portion of the control rights is transferred and driving control by the autonomous driving function continues, the HMI control device 100 requests the driver to start monitoring the surroundings or start gripping the steering wheel, etc. While the driver is monitoring the surroundings, the behavior determination unit 63 moves the host vehicle Am away from the passing line PLe of the emergency vehicle Ae based on the detection information of the periphery monitoring sensor 30. The behavior determination unit 63 may move the host vehicle Am away from the passing line PLe of the emergency vehicle Ae by controlling the host vehicle Am to follow another vehicle Ao ahead of the host vehicle.

[0051] Furthermore, while the host vehicle Am is waiting to turn right, the environment recognition unit 62 continues to recognize the lighting pattern of the traffic signal TL that the host vehicle Am is following. The environment recognition unit 62 determines whether the state of the traffic signal TL has transitioned to a lighting pattern that prohibits proceeding (prohibited proceeding state, hereinafter referred to as a red light).

[0052] The behavior determination unit 63 determines to implement handover control when the traffic signal TL in front of the host vehicle Am changes from green to red before the host vehicle Am exits the intersection area IA, even if the appeal sound SoA of the emergency vehicle Ae is not detected by the environment recognition unit 62. In this case, at least a part of the control of the host vehicle Am is handed over from the automatic driving function to the driver.

[0053] <Scene 2: Response to an Emergency Vehicle Behind That Is Sounding an Alert Sound> In scene 2 shown in Fig. 4 , the host vehicle Am is traveling in the straight-through lane Lt, one of multiple lanes included in the host vehicle's lane Ls, and is scheduled to proceed straight through an intersection IS. The emergency vehicle Ae is traveling behind the host vehicle Am and, like the host vehicle Am, is also scheduled to proceed straight through the intersection IS. In scene 2, the emergency vehicle Ae also approaches the intersection area IA while sounding an alert sound SoA. The traffic light TL located in front of the host vehicle Am and the emergency vehicle Ae is continuously lighting its green light, allowing the emergency vehicle Ae to proceed, at the time the emergency vehicle Ae enters the intersection area IA.

[0054] The environment recognition unit 62 detects the presence of an approaching emergency vehicle Ae based on the sound data and identifies the relative position and movement direction of the emergency vehicle Ae. In scene 2, after the host vehicle Am enters the intersection area IA, the environment recognition unit 62 detects the emergency vehicle Ae approaching from behind (see the host vehicle Am indicated by the dashed line in FIG. 4). If the environment recognition unit 62 estimates that the emergency vehicle Ae, whose approach has been detected, is about to enter the intersection area IA, it further detects the appeal sound SoA emitted by the emergency vehicle Ae.

[0055] When an emergency vehicle Ae emitting an appeal sound SoA is approaching the host vehicle Am from behind and the traffic light TL in front of the host vehicle is green, the behavior determination unit 63 performs stop control instead of handover control (see scene 1 in FIG. 3 ). In the stop control, the behavior determination unit 63 sets an avoidance position Ki that does not obstruct the emergency vehicle Ae's straight progress, left turn, or right turn. In the stop control of scene 1, the avoidance position Ki may be set within the intersection area IA or outside the intersection area IA. The behavior determination unit 63 moves the host vehicle Am away from the estimated passing line PLe of the emergency vehicle Ae and moves the host vehicle Am to the avoidance position Ki that is set so as not to block the path of the emergency vehicle Ae. The host vehicle Am waits for the emergency vehicle Ae to pass at the avoidance position Ki with its hazard lights flashing (see the host vehicle Am indicated by a solid line in FIG. 4 ).

[0056] <Scene 3: Responding to an Emergency Vehicle Changing Exit Direction> In scene 3 shown in Fig. 5 , the host vehicle Am is stopped within intersection area IA to wait for a right turn (see the host vehicle Am indicated by the dashed line in Fig. 5 ). The emergency vehicle Ae is traveling on a connecting road where the host vehicle Am will turn right and is approaching the intersection area IA from the right side of the host vehicle Am. The host vehicle Am is stopped in a position overlapping with the passing line PLe of the emergency vehicle Ae. While the host vehicle Am is waiting to turn right, the traffic light TL located in front of the host vehicle Am transitions from a green light state, which allows the host vehicle Am to proceed, to a lighting pattern, which prohibits the host vehicle Am from proceeding (prohibited state, hereinafter referred to as a red light).

[0057] After the approach of the emergency vehicle Ae is recognized in the intersection area IA, the behavior determination unit 63 initiates slow exit control when the traffic light TL followed by the host vehicle Am turns red, indicating a stop, before the host vehicle Am exits the intersection area IA. In the slow exit control, the behavior determination unit 63 sets an exit direction in which the emergency vehicle Ae is not present. In scene 3 in which an emergency exit is approaching from the right side, the behavior determination unit 63 sets a straight direction as the exit direction. The behavior determination unit 63 cancels the right turn and slows the host vehicle Am toward the connecting road in front, which is the set exit direction. The host vehicle Am leaves the intersection area IA by moving slowly (see the host vehicle Am indicated by the solid line in Figure 5). As a result, the emergency vehicle Ae can proceed straight through the intersection area IA.

[0058] <Scene 4: Responding to an Emergency Vehicle Exiting the Intersection Area> In scene 5 shown in Fig. 6 , the host vehicle Am is stopped within the intersection area IA to wait for a right turn (see the host vehicle Am indicated by the dashed line in Fig. 6 ). The emergency vehicle Ae is traveling toward the intersection IS on a connecting road located to the left of the host vehicle Am. While the host vehicle Am is waiting to turn right, the traffic light TL located in front of the host vehicle Am changes from a green light indicating that the host vehicle Am is permitted to proceed to a red light indicating that the host vehicle Am is not permitted to proceed.

[0059] The environment recognition unit 62 detects the presence of an emergency vehicle Ae approaching the host vehicle Am based on the sound data, and then determines the distance from the host vehicle Am to the emergency vehicle Ae. The environment recognition unit 62 continues to recognize the lighting pattern of the traffic signal TL that the host vehicle Am is following until the host vehicle Am exits the intersection area IA.

[0060] The behavior determination unit 63 changes the content of the behavior control for yielding to the emergency vehicle Ae according to the distance to the emergency vehicle Ae detected by the environment recognition unit 62. The behavior determination unit 63 determines whether to implement stop control or exit control based on whether the distance to the emergency vehicle Ae exceeds a predetermined threshold distance (for example, approximately 100 to 200 m). The stop control is behavior control that stops the host vehicle Am within the intersection area IA. The exit control is behavior control that causes the host vehicle Am to exit the intersection area IA in the planned exit direction.

[0061] The behavior determination unit 63 determines to execute exit control when the distance to the emergency vehicle Ae exceeds the threshold distance. The behavior determination unit 63 executes exit control (emergency exit control) to direct the host vehicle Am to the connecting road to which the emergency vehicle Ae will turn right, which is the planned exit route, and causes the host vehicle Am to exit the intersection area IA before the emergency vehicle Ae enters the intersection area IA. When the emergency vehicle Ae travels straight through the intersection IS, the behavior determination unit 63 causes the host vehicle Am to move to the shoulder of the road on the connecting road to which the emergency vehicle Ae will turn right in order to overtake the emergency vehicle Ae.

[0062] <Scene 5: Responding to an emergency vehicle waiting within an intersection area> In scene 5 shown in Figure 7, the host vehicle Am is stopped within the intersection area IA to wait to turn right (see the host vehicle Am indicated by the dashed line in Figure 7). There are other vehicles Ao waiting to turn right in front of and behind the host vehicle Am. The emergency vehicle Ae is traveling behind the host vehicle Am and plans to proceed straight through the intersection IS. To avoid the other vehicle Ao that has pulled over to the shoulder, the emergency vehicle Ae is traveling from the straight lane Lt of the multiple host vehicle lanes Ls into the right-turn lane Lr. The host vehicle Am and others are located on the passing line PLe of the emergency vehicle Ae. The traffic light TL located in front of the host vehicle Am and the emergency vehicle Ae continues to display a green light, allowing them to proceed.

[0063] The environment recognition unit 62 detects the presence of an emergency vehicle Ae approaching the host vehicle Am based on the sound data, and then determines the distance from the host vehicle Am to the emergency vehicle Ae. If the distance to the emergency vehicle Ae is equal to or less than a predetermined threshold distance, the environment recognition unit 62 determines whether a passing line PLe that allows the emergency vehicle Ae to pass when the host vehicle Am stops within the intersection area IA is secured within the area.

[0064] The behavior determination unit 63 allows the execution of stop control (in-area stop control) when the passing line PLe is secured within the intersection area IA. In the stop control of scene 5, the avoidance position Ki is set within the intersection area IA. When the distance to the emergency vehicle Ae is equal to or less than the threshold distance and the passing line PLe can be secured, the behavior determination unit 63 aborts the right turn and moves the host vehicle Am to the avoidance position Ki set within the area. The host vehicle Am waits for the emergency vehicle Ae to pass at the avoidance position Ki with its hazard flasher flashing (see the host vehicle Am indicated by the solid line in FIG. 7 ).

[0065] <Scene 6: Response to an Emergency Vehicle Before Entering an Intersection Area> In scene 6 shown in Fig. 8 , the host vehicle Am is traveling in the host vehicle lane Ls (straight-through lane Lt) toward the intersection IS. The emergency vehicle Ae is traveling on a crossroad that intersects with the host vehicle lane Ls at the intersection IS. The emergency vehicle Ae plans to make a right turn at the intersection IS. The traffic light TL located in front of the host vehicle Am is lit with a green light.

[0066] When the environment recognition unit 62 recognizes an emergency vehicle Ae approaching the host vehicle Am on the near side of the intersection IS, it further recognizes the relative direction in which the emergency vehicle Ae is located. When the environment recognition unit 62 detects the approach of the emergency vehicle Ae, it determines whether an intersection area IA located in the traveling direction of the host vehicle Am is an intersection area IA (hereinafter referred to as a priority control area IAp) in which priority control of traffic signals TL is performed to give priority to the passage of the emergency vehicle Ae. Priority control is control of traffic signals TL to support the emergency vehicle Ae in rushing to the scene. The environment recognition unit 62 recognizes an intersection area IA in which a scene rush support system (Fast Emergency Vehicle Preemption Systems, FAST) is implemented as a priority control area IAp. Information indicating whether the intersection area IA is a priority control area IAp may be pre-recorded in map data or may be provided to the in-vehicle communication device 39 via road-to-vehicle communication.

[0067] When the approach of the emergency vehicle Ae is recognized before the host vehicle Am enters the intersection area IA but the relative direction of the emergency vehicle Ae is not recognized, the behavior determination unit 63 starts preliminary deceleration control. In the preliminary deceleration control, the behavior determination unit 63 decelerates the host vehicle Am to a speed (e.g., about 20 km / h) that allows the host vehicle Am to stop just before the intersection area IA (see the host vehicle Am indicated by the dashed line in FIG. 8 ).

[0068] If the host vehicle Am approaches the stop line SL without recognizing the relative direction of the emergency vehicle Ae, the behavior determination unit 63 stops the host vehicle Am at the stop line SL before the intersection area IA (see the host vehicle Am shown with a solid line in FIG. 8 ). If the behavior determination unit 63 recognizes the approach of the emergency vehicle Ae before the host vehicle Am enters the intersection area IA, the behavior determination unit 63 stops the host vehicle Am before the stop line SL even if the traffic signal TL that the host vehicle Am follows is in a green light state allowing the host vehicle Am to proceed.

[0069] If an emergency vehicle Ae passes through the intersection area IA before the host vehicle Am enters the intersection area IA, the behavior determination unit 63 stops the host vehicle Am before the stop line SL even if the traffic light TL followed by the host vehicle Am is in a green light state. By such green light wait control, the behavior determination unit 63 does not allow the host vehicle Am to proceed into the intersection area IA during the current green light period. After the traffic light TL transitions to a red light, the behavior determination unit 63 allows the host vehicle Am to proceed into the intersection area IA during the next green light period.

[0070] Here, if the intersection area IA located in the direction of travel of the host vehicle Am is a priority control area IAp, the traffic light TL in front of the host vehicle is likely to be switched to red to give priority to the emergency vehicle Ae. Therefore, if the approach of the emergency vehicle Ae is recognized before the host vehicle Am enters the priority control area IAp, the behavior determination unit 63 stops the host vehicle Am earlier than if the approach of the emergency vehicle Ae is recognized before the host vehicle Am enters a normal intersection area IA that is not a priority control area IAp. In this case, the behavior determination unit 63 may stop the host vehicle Am at a position away from the stop line SL.

[0071] [Processing for Implementing Behavior Control at Intersections] Next, details of the behavior control processing for implementing the behavior control described above will be described based on FIGS. 9 and 10 and with reference to FIGS. 1 to 8. FIG.

[0072] <Behavior control process performed before entering intersection area> The behavior control process shown in Figure 9 (hereinafter referred to as the first control process) is started by the autonomous driving ECU 50 when the host vehicle Am approaches the intersection IS. The autonomous driving ECU 50 starts the first control process, for example, when the distance from the host vehicle Am to the intersection IS becomes a predetermined distance near the intersection (for example, approximately 300 to 500 m). The autonomous driving ECU 50 ends the first control process when the host vehicle Am enters the intersection area IA.

[0073] In S11 of the first control process, the environment recognition unit 62 recognizes an emergency vehicle Ae approaching the host vehicle Am. If the emergency vehicle Ae is not recognized (S11: NO), the process of S11 is repeated to continue detecting the approach of the emergency vehicle Ae. On the other hand, if the emergency vehicle Ae is recognized (S11: YES), the environment recognition unit 62 determines in S12 whether the relative direction of the emergency vehicle Ae has been recognized.

[0074] If the relative direction of the emergency vehicle Ae is not recognized (S12: NO), the behavior determination unit 63 starts preliminary deceleration control (see FIG. 8 ) in S13 to decelerate the host vehicle Am to a speed at which the host vehicle Am can be stopped before the intersection area IA. On the other hand, if the relative direction of the emergency vehicle Ae is recognized (S12: YES), the preliminary deceleration control is omitted.

[0075] In S14, the environment recognition unit 62 determines (determines) whether the intersection area IA located in the traveling direction of the host vehicle Am is a priority control area IAp (see FIG. 8 ). If the intersection area IA is a priority control area IAp (S14: YES), the behavior determination unit 63 performs short-distance stop control in S15. On the other hand, if the intersection area IA is not a priority control area IAp (S14: NO), the behavior determination unit 63 performs normal stop control in S16. In the short-distance stop control, the behavior determination unit 63 stops the host vehicle Am earlier (in a shorter distance) than in the normal stop control. According to the short-distance stop control, the host vehicle Am can be stopped at a position farther from the stop line SL. On the other hand, in the normal stop control, the behavior determination unit 63 stops the host vehicle Am just before the stop line SL or behind another vehicle Ao that is stopped at the stop line SL.

[0076] In S17, the behavior determination unit 63 performs green light wait control. The behavior determination unit 63 stops the host vehicle Am before the intersection area IA even if the traffic light TL followed by the host vehicle Am is in a green light state allowing the host vehicle Am to proceed. Furthermore, even if an emergency vehicle Ae has passed through the intersection area IA, the behavior determination unit 63 does not allow the host vehicle Am to proceed into the intersection area IA during the current green light period. The behavior determination unit 63 waits for the traffic light TL, which has transitioned to a red light, to switch back to a green light before allowing the host vehicle Am to proceed into the intersection area IA.

[0077] 10 (hereinafter referred to as the second control process) is started by the autonomous driving ECU 50 based on the host vehicle Am entering the intersection area IA. The autonomous driving ECU 50 ends the second control process based on the host vehicle Am leaving the intersection area IA.

[0078] In S31 of the second control process, the environment recognition unit 62 recognizes an emergency vehicle Ae approaching the host vehicle Am. If the emergency vehicle Ae is not recognized (S31: NO), the process of S31 is repeated to continue detecting the approach of the emergency vehicle Ae. On the other hand, if the emergency vehicle Ae is recognized (S31: YES), the environment recognition unit 62 determines in S32 whether or not it has detected the appeal sound SoA emitted by the emergency vehicle Ae.

[0079] If the environment recognition unit 62 detects the appeal sound SoA (S32: YES), in S33, the environment recognition unit 62 grasps the relative position and movement direction of the emergency vehicle Ae and determines whether the emergency vehicle Ae is approaching the host vehicle Am from behind. If the emergency vehicle Ae is approaching from behind (S33: YES), in S43, the behavior determination unit 63 performs stop control and stops the host vehicle Am at an avoidance position Ki set so as not to block the path of the emergency vehicle Ae (see FIG. 4). On the other hand, if the emergency vehicle Ae is approaching from a direction other than behind (from the front or side) (S33: NO), the behavior determination unit 63 determines to perform handover control (driving change) in S42 and transfers at least a portion of the control of the host vehicle Am from the autonomous driving function to the driver (see FIG. 3).

[0080] If the environment recognition unit 62 has not detected the appeal sound SoA (S32: NO), it determines in S34 whether the traffic light TL in front of the vehicle is lit red, indicating a stop. If the traffic light TL is red (S34: YES), the behavior determination unit 63 determines in S35 whether the system using the autonomous driving function can respond to the emergency vehicle Ae. For example, if there are many other vehicles Ao in the intersection area IA and the traffic situation is complicated, the behavior determination unit 63 determines that the system cannot respond (S35: NO). In this case, the behavior determination unit 63 determines in S42 to implement handover control (driving changeover).

[0081] When the behavior determination unit 63 determines that the system can handle the situation (S35: YES), it determines in S38 whether or not an emergency vehicle Ae is present at the destination where the host vehicle Am is about to exit the intersection area IA. If an emergency vehicle Ae is present at the intended exit destination (S38: YES), the behavior determination unit 63 performs slow exit control in S41. In the slow exit control, the behavior determination unit 63 sets an exit direction in which no emergency vehicle Ae is present, and causes the host vehicle Am to exit the intersection area IA by moving slowly in the set exit direction (see FIG. 5). On the other hand, when an emergency vehicle Ae is not present at the intended exit destination (S38: NO), the behavior determination unit 63 performs exit control (emergency exit control) in S40 to direct the host vehicle Am to the intended exit destination (see FIG. 6).

[0082] On the other hand, if the traffic light TL in front of the host vehicle is not red (S34: NO), the environment recognition unit 62 determines the distance to the approaching emergency vehicle Ae in S36 and determines whether the distance exceeds a predetermined threshold distance. If the distance to the emergency vehicle Ae exceeds the threshold distance (S36: YES), the behavior determination unit 63 performs exit control in S40, causing the host vehicle Am to exit the intersection area IA toward the planned exit destination (see FIG. 6 ).

[0083] On the other hand, if the distance to the emergency vehicle Ae does not exceed the threshold distance (S36: NO), the environment recognition unit 62 determines in S37 whether a passing line PLe that allows the emergency vehicle Ae to pass is secured within the intersection area IA when the host vehicle Am stops within the intersection area IA. For example, if the intersection IS is a small intersection and a passing line PLe is not secured within the intersection area IA (S37: NO), the behavior determination unit 63 performs exit control in S40. On the other hand, if the intersection IS is a large intersection and a passing line PLe is secured within the intersection area IA (S37: YES), the behavior determination unit 63 performs in-area stop control in S39, stopping the host vehicle Am within the intersection area IA (see FIG. 7 ).

[0084] (Summary of First Embodiment) In the first embodiment described so far, when the approach of an emergency vehicle Ae is recognized while the host vehicle Am is located in the intersection area IA, the behavior of the host vehicle Am is controlled to yield to the emergency vehicle Ae in the intersection area IA. Therefore, the host vehicle Am is less likely to interfere with other vehicles Ao and the emergency vehicle Ae present in the intersection area IA. As a result, even if the host vehicle Am encounters the emergency vehicle Ae in the intersection area IA where other vehicles Ao and the like are present around the host vehicle, the host vehicle Am is less likely to have a negative impact on the surrounding area.

[0085] Additionally, in the first embodiment, when an emergency vehicle Ae is detected using sound data collected by the exterior acoustic sensor 32 mounted on the host vehicle Am, an appeal sound SoA emitted by the emergency vehicle Ae in relation to the intersection area IA is further detected based on the sound data. Then, based on the detection of the appeal sound SoA, at least a portion of the control of the host vehicle Am is transferred from the autonomous driving function to the driver. By transferring the driving operation authority based on the detection of the appeal sound SoA, avoidance measures utilizing the driver's judgment can be initiated early in anticipation of a complex traffic situation that the autonomous driving function cannot handle. Therefore, the adverse impact of the host vehicle Am on the surrounding area can be reduced.

[0086] In the first embodiment, at least one of an emphasis siren sound emitted by the emergency vehicle Ae upon entering the intersection area IA and an announcement sound emitted by the emergency vehicle Ae is detected as the appeal sound SoA. Based on the detection of the emphasis siren sound and the announcement sound, the driver can be handed over driving at an appropriate time.

[0087] Furthermore, in the first embodiment, when an emergency vehicle Ae emitting an appeal sound SoA approaches the host vehicle Am from behind, instead of transferring control, behavioral control is performed to move the host vehicle Am to a position that does not block the path of the emergency vehicle Ae. It is difficult for the driver to grasp the situation behind the host vehicle. Therefore, when an emergency vehicle Ae approaching from behind is emitting an appeal sound SoA, moving the host vehicle Am to a position that does not block the path of the emergency vehicle Ae may be prioritized over transferring control.

[0088] Additionally, in the first embodiment, after the approach of the emergency vehicle Ae is recognized in the intersection area IA, if the traffic signal TL turns red before the host vehicle Am exits the intersection area IA, one of the slow exit control, the emergency exit control, and the handover control is implemented. In this way, by providing a plurality of behavioral controls as options, the host vehicle Am can act appropriately so as not to adversely affect the surroundings, even in a scene where the urgency of responding to the emergency vehicle Ae increases due to the transition of the traffic signal to red.

[0089] In the first embodiment, when the host vehicle Am stops within the intersection area IA, it is determined whether a passing line PLe that allows the emergency vehicle Ae to pass is secured within the area. If the passing line PLe is secured within the area, stop control that stops the host vehicle Am within the area is permitted. This stop control allows the host vehicle Am to take advantage of the large area of ​​the intersection area IA at a large intersection IS and retreat to an avoidance position Ki that does not interfere with the emergency vehicle Ae, other vehicles Ao, etc.

[0090] Furthermore, in the first embodiment, the distance to the approaching emergency vehicle Ae is grasped. Then, depending on the distance to the emergency vehicle Ae, it is determined whether to perform stop control, which stops the host vehicle Am within the intersection area IA, or exit control, which causes the host vehicle Am to exit the intersection area IA. As a result, it is possible to evacuate the host vehicle Am to an appropriate location that does not block the path of the emergency vehicle Ae, taking into account the grace period until the emergency vehicle Ae reaches the intersection area IA.

[0091] In addition, in the first embodiment, if the approach of the emergency vehicle Ae is recognized before the host vehicle Am enters the intersection area IA, the host vehicle Am stops even if the traffic light TL that the host vehicle Am follows is in a green light state allowing the host vehicle Am to proceed. By controlling the host vehicle Am to suppress entry into the intersection area IA in this way, it becomes less likely that the host vehicle Am will encounter the emergency vehicle Ae after entering the intersection area IA.

[0092] Furthermore, in the first embodiment, if an emergency vehicle Ae passes through the intersection area IA before the host vehicle Am enters the intersection area IA, the host vehicle Am will not proceed into the intersection area IA during the current green light period even if the traffic signal TL is in the green light state. The host vehicle Am will proceed into the intersection area IA during the next green light period. As a result of the above, for example, in a scene where multiple emergency vehicles Ae are approaching at different times, it is less likely that the host vehicle Am will encounter another emergency vehicle Ae after entering the intersection area IA.

[0093] Furthermore, in the first embodiment, the relative direction of an emergency vehicle Ae approaching the host vehicle Am is also recognized. If the approach of the emergency vehicle Ae is recognized before the host vehicle Am enters the intersection area IA but the relative direction of the emergency vehicle Ae is not recognized, the host vehicle Am decelerates to a speed that allows the host vehicle Am to stop just before the intersection area IA. This preliminary deceleration control allows the host vehicle Am to become sufficiently slow (increased) in speed by the time the relative direction of the emergency vehicle Ae is recognized. As a result, the host vehicle Am can smoothly initiate behavioral control in response to the emergency vehicle Ae.

[0094] In addition, in the first embodiment, if the relative direction of the emergency vehicle Ae cannot be recognized, the host vehicle Am stops in front of the intersection area IA. In this way, if entry into the intersection area IA is restricted when the direction of the approaching emergency vehicle Ae cannot be determined, it becomes less likely that the host vehicle Am will encounter the emergency vehicle Ae within the intersection area IA.

[0095] In the first embodiment, the host vehicle Am determines whether an intersection area IA located in the traveling direction of the host vehicle Am is a priority control area IAp, where priority control of traffic signals TL is performed to prioritize the passage of emergency vehicles Ae. If the approach of the emergency vehicle Ae is recognized before the host vehicle Am enters the priority control area IAp, the host vehicle Am stops earlier than if the approach of the emergency vehicle Ae is recognized before the host vehicle Am enters an intersection area IA that is not a priority control area IAp. In the priority control area IAp, the approach of the emergency vehicle Ae may suddenly cause the traffic signal TL to switch to red. Therefore, if the host vehicle Am stops traveling, the host vehicle Am is less likely to have to brake suddenly to respond to a sudden red light.

[0096] In the first embodiment, the exterior acoustic sensor 32 corresponds to the "exterior sound detection unit", the environment recognition unit 62 corresponds to the "exterior recognition unit", the behavior determination unit 63 corresponds to the "behavior control unit", and the automatic driving ECU 50 corresponds to the "automatic driving control device".

[0097] Second Embodiment A second embodiment of the present disclosure is a modification of the first embodiment. In the second embodiment, the content of behavior control in a scene in which an emergency vehicle Ae emitting an appeal sound SoA approaches an intersection area IA from behind the host vehicle Am (see scene 2 in FIG. 4 ) is different from that in the first embodiment.

[0098] 11 , when an emergency vehicle Ae sounding the appeal sound SoA is approaching from behind (S33: YES), the information linkage unit 61 outputs a request to the HMI control device 100 to perform an emergency vehicle approach notification in S33a. The information linkage unit 61 provides the driver with approach notification information related to the approach of the emergency vehicle Ae through the emergency vehicle approach notification in cooperation with the HMI control device 100. The emergency vehicle approach notification conveys to the driver details of the current situation in which the emergency vehicle Ae is approaching from behind the vehicle, the level of urgency, and the like.

[0099] After the information linking unit 61 issues an emergency vehicle approach notification, the behavior determining unit 63 performs handover control in S42. The behavior determining unit 63 hands over at least a portion of the control of the driving operation to the driver who understands the current situation through the presentation of the approach notification information. The driver, who understands that an emergency vehicle Ae is approaching from behind through the emergency vehicle approach notification, moves his / her own vehicle Am while adjusting to the behavior of the other vehicle Ao so as not to block the path of the emergency vehicle Ae.

[0100] The second embodiment described so far also achieves the same effect as the first embodiment, and even if the vehicle Am encounters an emergency vehicle Ae in an intersection area IA where other vehicles Ao, etc. are present around the vehicle, the vehicle Am may be less likely to have a negative impact on the surrounding area.

[0101] Additionally, in the second embodiment, when an emergency vehicle Ae emitting an appeal sound SoA approaches the host vehicle Am from behind, approach notification information related to the approach of the emergency vehicle Ae is displayed to the driver. Then, along with the display of the approach notification information, control is handed over to the driver. As described above, the driver can reliably notice the rear emergency vehicle Ae, which is difficult to see, from the displayed approach notification information. Therefore, after acquiring control, the driver can select appropriate actions that do not adversely affect the emergency vehicle Ae and other vehicles Ao. In the second embodiment, the information linking unit 61 corresponds to the "notification unit."

[0102] (Other Embodiments) Although multiple embodiments of the present disclosure have been described above, the present disclosure should not be construed as being limited to the above-described embodiments, and can be applied to various embodiments and combinations within the scope that does not deviate from the gist of the present disclosure.

[0103] In a first modification of the above embodiment, when an emergency vehicle Ae emitting an appeal sound SoA approaches the host vehicle Am from a position other than the rear, the behavior determination unit 63 determines to implement a driving changeover to switch to manual driving. On the other hand, when an emergency vehicle Ae emitting an appeal sound SoA approaches the host vehicle Am from the rear, the behavior determination unit 63 implements a handover control to request the driver to start periphery monitoring, while also implementing a stop control to move the host vehicle Am to an avoidance position Ki. As in the first modification described above, the content of the behavior control based on the detection of the appeal sound SoA may be changed as appropriate.

[0104] In a second modification of the above embodiment, even when an emergency vehicle Ae emitting the appeal sound SoA approaches the host vehicle Am from a direction other than the rear, the information linking unit 61 and the HMI control device 100 issue an emergency vehicle approach notification. In a third modification of the above embodiment, the emergency vehicle approach notification is issued regardless of whether the emergency vehicle Ae is emitting the appeal sound SoA. As in the first and second modifications, the emergency vehicle approach notification may be issued as appropriate.

[0105] The autonomous driving ECU 50 of the above embodiment can execute any one of the slow exit control, emergency exit control, and handover control when the approach of the emergency vehicle Ae and the transition to a red light are detected at the same time. On the other hand, the autonomous driving ECU 50 of the fourth modification of the above embodiment can execute only some of these behavioral controls.

[0106] In the above embodiment, the threshold distance that determines whether to perform the in-area stop control or the emergency exit control may be changed as appropriate. In addition, the behavior determination unit 63 may perform the in-area stop control when the distance to the emergency vehicle Ae exceeds the threshold distance, and may perform the emergency exit control when the distance to the emergency vehicle Ae is equal to or shorter than the threshold distance.

[0107] The green light waiting control in the above embodiment may be omitted. Similarly, the preliminary deceleration control based on the detection of the emergency vehicle Ae and the switching of the stop control based on whether or not the vehicle is in the priority control area IAp may also be omitted.

[0108] The autonomous driving ECU 50 in the above embodiment was capable of executing both driving assistance control at autonomous driving level 2 and autonomous driving control at autonomous driving level 3. The autonomous driving ECU 50 in variant 5 of the above embodiment executes only one of driving assistance control and autonomous driving control. Furthermore, the autonomous driving ECU 50 in variant 6 of the above embodiment executes autonomous driving control at autonomous driving level 4 or autonomous driving level 5, in which the driver does not take over driving. Furthermore, the autonomous driving ECU 50 may be configured to autonomously drive the host vehicle Am without a driver on board, under remote monitoring by a remote monitor.

[0109] At least some of the functions of the autonomous driving ECU 50 may be implemented in another control device included in the in-vehicle system. For example, in Modification 7 of the above embodiment, a dedicated ECU (hereinafter referred to as the acoustic analysis ECU) that analyzes sound data and outputs the analysis information to the environment recognition unit 62 is provided on the in-vehicle LAN. The function of recognizing an emergency vehicle Ae based on the sound data is implemented in the acoustic analysis ECU. In this Modification 7, a system including the autonomous driving ECU 50 and the acoustic analysis ECU may correspond to an "autonomous driving control device."

[0110] In Modification 8 of the above embodiment, the functions of the automatic driving ECU 50 and the HMI control device 100 are provided by a single integrated ECU. In this Modification 8, the integrated ECU corresponds to the "automatic driving control device," and the notification control unit built in the integrated ECU corresponds to the "notification implementation unit." In addition, the functions of the automatic driving control device according to the present disclosure may be realized by cooperation between the automatic driving ECU 50 and the HMI control device 100. In this embodiment, a system including the automatic driving ECU 50 and the HMI control device 100 corresponds to the "automatic driving control device," and the HMI control device 100 corresponds to the "notification implementation unit."

[0111] In the above embodiment, the functions provided by the autonomous driving ECU 50 and the like can be provided by software and hardware that executes the software, software alone, hardware alone, or a combination of these. Furthermore, when such functions are provided by electronic circuits as hardware, each function can also be provided by digital circuits including multiple logic circuits or analog circuits. Furthermore, the software for realizing such functions may include, at least in part, code automatically generated by, for example, a neural network or language model trained using real-world camera images.

[0112] Each processing unit in the above embodiments is hardware for arithmetic processing coupled to a RAM. The processing unit includes at least one arithmetic core, such as a central processing unit (CPU) and a graphics processing unit (GPU). The processing unit may further include a field-programmable gate array (FPGA), a neural network processing unit (NPU), a digital signal processor (DSP), and an IP core with other dedicated functions. The processing unit is not limited to being individually mounted on a printed circuit board. The processing unit may be mounted on an application-specific integrated circuit (ASIC), a system on chip (SoC), a chiplet integration, an FPGA, or the like.

[0113] In the above embodiments, the form of the storage medium (non-transitory tangible storage medium) that stores various programs and the like may be changed as appropriate. Furthermore, the storage medium is not limited to a configuration provided on a circuit board, but may be provided in the form of a memory card or the like, inserted into a slot, and electrically connected to a control circuit such as an autonomous driving ECU. Furthermore, the storage medium may be an optical disk, hard disk drive, solid state drive, or the like that serves as a source from which programs are copied or distributed to the autonomous driving ECU or the like.

[0114] The vehicle equipped with the above-described autonomous driving ECU 50 is not limited to a typical private passenger car (Personally Owned Vehicle, POV). The vehicle equipped with the autonomous driving ECU 50 may also be a rental car vehicle, a manned taxi vehicle, a ride-sharing vehicle, a freight vehicle, a bus, or the like. The vehicle equipped with the autonomous driving ECU 50 may be a right-hand drive vehicle or a left-hand drive vehicle. Furthermore, the traffic environment in which the vehicle travels may be one based on left-hand traffic or one based on right-hand traffic. That is, in a traffic environment in which vehicles drive on the right, the "waiting to turn right" situation in each of the above-described scenes corresponds to the "waiting to turn left" situation. The autonomous driving control according to the present disclosure may be optimized as appropriate according to the road traffic laws of each country and region, as well as the steering wheel position of the vehicle.

[0115] The controller and methods described herein may be implemented by a special-purpose computer comprising a processor programmed to perform one or more functions embodied in a computer program. Alternatively, the apparatus and methods described herein may be implemented by special-purpose hardware logic circuitry. Alternatively, the apparatus and methods described herein may be implemented by one or more special-purpose computers comprising a processor executing a computer program in combination with one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by a computer on a computer-readable non-transitory storage medium.

[0116] (Disclosure of Technical Ideas) This specification discloses multiple technical ideas described in the following multiple clauses. Some clauses may be described in a multiple dependent form, with the subsequent clause alternatively referring to the preceding clause. Furthermore, some clauses may be described in a multiple dependent form, with the subsequent clause referring to another multiple dependent clause. These multiple dependent clauses define multiple technical ideas.

[0117] (Technical Idea 1) An autonomous driving control device that controls the traveling of a host vehicle (Am) using an autonomous driving function, comprising: an exterior recognition unit (62) that recognizes an emergency vehicle (Ae) approaching the host vehicle, and a behavior control unit (63) that, when the approach of the emergency vehicle is recognized while the host vehicle is located in an intersection area (IA), controls the behavior of the host vehicle to yield to the emergency vehicle in the intersection area. (Technical Idea 2) The autonomous driving control device according to Technical Idea 1, wherein the exterior recognition unit detects the emergency vehicle using sound data collected by an exterior sound detection unit (32) mounted on the host vehicle, and further detects an appeal sound (SoA) emitted by the emergency vehicle in relation to the intersection area based on the sound data, and the behavior control unit transfers at least a portion of control of the host vehicle from the autonomous driving function to a driver based on the detection of the appeal sound. (Technical Idea 3) The autonomous driving control device according to Technical Idea 2, wherein the vehicle exterior recognition unit detects, as the appeal sound, at least one of an emphasized siren sound emitted by the emergency vehicle as it enters the intersection area and an announcement sound emitted by the emergency vehicle. (Technical Idea 4) The autonomous driving control device according to Technical Idea 2 or 3, wherein, when the emergency vehicle emitting the appeal sound is approaching the host vehicle from behind, the behavior control unit moves the host vehicle to a position that does not block the path of the emergency vehicle instead of transferring control. (Technical Idea 5) The autonomous driving control device according to Technical Idea 2 or 3, further comprising: a notification implementation unit (61) that, when the emergency vehicle emitting the appeal sound is approaching the host vehicle from behind, presents approach notification information related to the approach of the emergency vehicle to the driver, and when the emergency vehicle emitting the appeal sound is approaching the host vehicle from behind.(Technical Idea 6) The autonomous driving control device according to any one of Technical Ideas 1 to 5, wherein, after recognizing the approach of the emergency vehicle in the intersection area, if a traffic light (TL) followed by the host vehicle enters a state instructing the host vehicle to stop before the host vehicle exits the intersection area, the behavior control unit performs one of the following: slow exit control, which causes the host vehicle to exit the intersection area by moving slowly in a direction where the emergency vehicle is not present; emergency exit control, which causes the host vehicle to head to a planned exit destination; and transfer control, which transfers at least a portion of control of the host vehicle from the autonomous driving function to a driver. (Technical Idea 7) The autonomous driving control device according to any one of Technical Ideas 1 to 6, wherein, when the host vehicle stops within a region of the intersection area, the vehicle exterior recognition unit determines whether a passing line (PLe) for allowing the emergency vehicle to pass is secured within the region, and the behavior control unit allows implementation of stop control, which stops the host vehicle within the region, if the passing line is secured within the region. (Technical Idea 8) The autonomous driving control device according to any one of Technical Ideas 1 to 7, wherein the vehicle exterior recognition unit grasps the distance to the approaching emergency vehicle, and the behavior control unit determines, according to the distance to the emergency vehicle, whether to implement stop control, which stops the host vehicle within the intersection area, or exit control, which causes the host vehicle to exit the intersection area. (Technical Idea 9) The autonomous driving control device according to any one of Technical Ideas 1 to 8, wherein, when the approach of the emergency vehicle is recognized before the host vehicle enters the intersection area, the behavior control unit stops the host vehicle even if a traffic light (TL) followed by the host vehicle is in a state allowing the host vehicle to proceed. (Technical Idea 10) The automatic driving control device according to any one of Technical Ideas 1 to 9, wherein, when the emergency vehicle passes through the intersection area before the host vehicle enters the intersection area, even if the state of a traffic signal (TL) followed by the host vehicle is in a proceeding permission state that allows the host vehicle to proceed, the behavior control unit does not cause the host vehicle to proceed into the intersection area during the current period of the proceeding permission state, but causes the host vehicle to proceed into the intersection area during the next period of the proceeding permission state.(Technical Idea 11) The autonomous driving control device according to any one of Technical Ideas 1 to 10, wherein the vehicle exterior recognition unit further recognizes a relative direction of the emergency vehicle approaching the host vehicle, and the action control unit, when the approach of the emergency vehicle is recognized before the host vehicle enters the intersection area but the relative direction of the emergency vehicle is not recognized, decelerates the host vehicle to a speed that allows the host vehicle to be stopped before the intersection area. (Technical Idea 12) The autonomous driving control device according to Technical Idea 11, when the relative direction of the emergency vehicle is not recognized, stops the host vehicle before the intersection area. (Technical Idea 13) The autonomous driving control device according to any one of Technical Ideas 1 to 12, wherein the vehicle exterior recognition unit determines whether the intersection area located in the traveling direction of the host vehicle is a priority control area (IAp) where priority control of traffic signals (TL) is performed to give priority to the passage of the emergency vehicle, and the behavior control unit, when the approach of the emergency vehicle is recognized before the host vehicle enters the priority control area, stops the host vehicle earlier than when the approach of the emergency vehicle is recognized before the host vehicle enters the intersection area that is not the priority control area. (Technical Idea 14) An autonomous driving control program that controls traveling of the host vehicle (Am) by an autonomous driving function, the autonomous driving control program causing at least one processing unit (51) to execute processes including: recognizing an emergency vehicle (Ae) approaching the host vehicle (Ae) (S31); and, when the approach of the emergency vehicle is recognized while the host vehicle is located in an intersection area (IA), controlling the behavior of the host vehicle to give way to the emergency vehicle in the intersection area (S39 to S43).

Claims

1. An automatic driving control device that controls the driving of a host vehicle (Am) using an automatic driving function, comprising: an outside-vehicle recognition unit (62) that recognizes an emergency vehicle (Ae) approaching the host vehicle; and a behavior control unit (63) that, when the approach of the emergency vehicle is recognized while the host vehicle is located in an intersection area (IA), controls the behavior of the host vehicle to give way to the emergency vehicle in the intersection area.

2. The autonomous driving control device of claim 1, wherein the exterior recognition unit detects the emergency vehicle using sound data collected by an exterior sound detection unit (32) mounted on the vehicle, and further detects an appeal sound (SoA) emitted by the emergency vehicle in relation to the intersection area based on the sound data, and the behavior control unit transfers at least a portion of the control of the vehicle from the autonomous driving function to the driver based on the detection of the appeal sound.

3. The automatic driving control device described in claim 2, wherein the vehicle exterior recognition unit detects at least one of an accentuated siren sound emitted by the emergency vehicle as it enters the intersection area and an announcement sound emitted by the emergency vehicle as the appeal sound.

4. The automatic driving control device of claim 2, wherein, when the emergency vehicle emitting the appeal sound approaches the host vehicle from behind, the behavior control unit moves the host vehicle to a position that does not block the path of the emergency vehicle instead of transferring control.

5. An automatic driving control device as described in claim 2, further comprising an alert implementation unit (61) that, when the emergency vehicle emitting the appeal sound approaches from behind the vehicle, presents approach notification information related to the approach of the emergency vehicle to the driver, and when the emergency vehicle emitting the appeal sound approaches from behind the vehicle, the behavior control unit presents the approach notification information to the driver and transfers control rights.

6. The automatic driving control device according to claim 1, wherein, after the approach of the emergency vehicle is recognized in the intersection area, if the traffic light (TL) followed by the vehicle indicates a stop before the vehicle exits the intersection area, the behavior control unit performs one of the following: slow exit control, which causes the vehicle to exit the intersection area by moving slowly in a direction where the emergency vehicle is not present; emergency exit control, which causes the vehicle to head to the planned exit destination; and transfer control, which transfers at least a portion of the control of the vehicle from the automatic driving function to the driver.

7. The automatic driving control device described in claim 1, wherein the exterior recognition unit determines whether a passing line (PLe) for allowing the emergency vehicle to pass is secured within the intersection area when the vehicle stops within the area, and the behavior control unit allows the implementation of stop control to stop the vehicle within the area if the passing line is secured within the area.

8. The automatic driving control device described in claim 1, wherein the exterior recognition unit grasps the distance to the approaching emergency vehicle, and the behavior control unit determines, depending on the distance to the emergency vehicle, whether to implement stop control, which stops the vehicle within the intersection area, or exit control, which causes the vehicle to exit the intersection area.

9. The automatic driving control device described in claim 1, wherein the behavior control unit stops the vehicle when the approach of the emergency vehicle is recognized before the vehicle enters the intersection area, even if the traffic light (TL) that the vehicle is following allows the vehicle to proceed.

10. The automatic driving control device of claim 1, wherein, if the emergency vehicle passes through the intersection area before the host vehicle enters the intersection area, the behavior control unit does not allow the host vehicle to proceed into the intersection area during the current period of the proceeding permission state, even if the state of the traffic light (TL) followed by the host vehicle is in a proceeding permission state that allows the vehicle to proceed, but allows the host vehicle to proceed into the intersection area during the next period of the proceeding permission state.

11. The automatic driving control device of claim 1, wherein the exterior recognition unit further recognizes the relative direction of the emergency vehicle approaching the host vehicle, and the behavior control unit, when the approach of the emergency vehicle is recognized before the host vehicle enters the intersection area but the relative direction of the emergency vehicle is not recognized, decelerates the host vehicle to a speed that allows it to stop just before the intersection area.

12. The automatic driving control device according to claim 11, wherein the behavior control unit stops the vehicle in front of the intersection area if the relative direction of the emergency vehicle is not recognized.

13. The automatic driving control device described in claim 1, wherein the outside-vehicle recognition unit determines whether the intersection area located in the direction of travel of the vehicle is a priority control area (IAp) where priority control of traffic lights (TL) is performed to give priority to the passage of the emergency vehicle, and the behavior control unit stops the vehicle earlier when the approach of the emergency vehicle is recognized before the vehicle enters the priority control area than when the approach of the emergency vehicle is recognized before the vehicle enters the intersection area that is not the priority control area.

14. An autonomous driving control method for controlling the driving of a host vehicle (Am) using an autonomous driving function, the autonomous driving control method including the steps of: recognizing an emergency vehicle (Ae) approaching the host vehicle (S31); and, if the host vehicle is located in an intersection area (IA) and the approach of the emergency vehicle is recognized, controlling the behavior of the host vehicle to give way to the emergency vehicle in the intersection area (S39 to S43).

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