WO2024232199A1 - Vehicle control device and vehicle control method - Google Patents

Abstract

According to the present invention, an autonomous driving ECU is used in a host vehicle capable of traveling through autonomous traveling control in which a driver does not have a periphery monitoring obligation, and functions as a vehicle control device. The autonomous driving ECU ascertains that the traveling control state of the host vehicle is switched to a state of traveling by means of the autonomous traveling control. In an autonomous travel period during which the host vehicle travels by means of autonomous traveling control, the autonomous driving ECU performs silencing control for silencing the interior of the vehicle cabin of the host vehicle more than in a monitoring-required period in which the driver has a periphery monitoring obligation.

Description

Vehicle control device and vehicle control method CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on Patent Application No. 2023-078776 filed in Japan on May 11, 2023, and Patent Application No. 2023-156250 filed in Japan on September 21, 2023, and the contents of the original applications are incorporated by reference in their entirety.

The disclosure in this specification relates to vehicle control technology used in a vehicle that can run autonomously without the driver having to monitor the surroundings.

Patent Document 1 describes a vehicle control system that controls the automatic driving of a vehicle. Vehicles equipped with the vehicle control system of Patent Document 1 are expected to have not only a driver, but also passengers who are not involved in driving (hereinafter, passengers) on board.

JP 2023-47867 A

In a vehicle that runs using autonomous driving such as that described in Patent Document 1, passengers are likely to feel uneasy about whether autonomous driving control is being performed correctly. In particular, when the vehicle is running using autonomous driving control that does not require the driver to monitor the surroundings, and the driver is not monitoring the surroundings, if the noise inside the vehicle increases while driving, passengers may become increasingly uneasy about the autonomous driving control.

The purpose of this disclosure is to provide a vehicle control device and vehicle control method that can reduce the anxiety that passengers who are not involved in driving feel about autonomous driving control.

In order to achieve the above object, one disclosed embodiment is a vehicle control device used in a host vehicle capable of running under autonomous driving control with no obligation on the driver to monitor the surroundings, the vehicle control device comprising: a control grasping unit that grasps that the driving control state of the host vehicle has been switched to a state in which the host vehicle runs under autonomous driving control; and a noise reduction control unit that, during an automatic driving period in which the host vehicle runs under autonomous driving control, implements noise reduction control to reduce noise inside the host vehicle compared to a monitoring period in which the driver is obligated to monitor the surroundings.

Another disclosed aspect is a vehicle control method used in a host vehicle capable of running under autonomous driving control with no obligation on the driver to monitor the surroundings, the vehicle control method including, in processing performed by at least one processing unit, a step of grasping that the driving control state of the host vehicle has been switched to a state in which the host vehicle runs under autonomous driving control, and during an automatic driving period in which the host vehicle runs under autonomous driving control, implementing noise reduction control to reduce noise inside the host vehicle compared to a monitoring period in which the driver is obligated to monitor the surroundings.

In these aspects, during the automatic driving period when the vehicle is driven by the autonomous driving control, noise reduction control is implemented, and the interior of the vehicle can be made quieter. Therefore, in driving conditions where the driver is not monitoring the surroundings, it is possible to suppress the anxiety that passengers who are not involved in driving feel about the autonomous driving control due to noise inside the vehicle caused by driving.

Note 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. In addition, claims that are not explicitly stated in the claims may be combined together if no particular problems arise with the combination.

1 is a diagram showing an overall view of an in-vehicle network including an autonomous driving ECU according to a first embodiment of the present disclosure. FIG. 2 is a block diagram showing details of an autonomous driving ECU. 5 is a flowchart showing details of a mode switching process performed by an autonomous driving ECU. 5 is a flowchart showing details of a power control process that the autonomous driving ECU executes in cooperation with the cruise control ECU. 5 is a flowchart showing details of a window control process performed by the autonomous driving ECU in cooperation with the body ECU. 4 is a flowchart showing details of a vehicle interior control process performed by the autonomous driving ECU in cooperation with the HMI control device. FIG. 11 is a block diagram showing details of an autonomous driving ECU according to a second embodiment of the present disclosure. FIG. 11 is a diagram showing an example of output timing of background sound that is output during an autonomous driving period. FIG. 11 is a diagram showing an example of output timing of background sound that is output during an autonomous driving period. 5 is a flowchart showing details of an autonomous driving notification process performed by an autonomous driving ECU. 5 is a flowchart showing details of a behavior change notification process executed by an autonomous driving ECU. 5 is a flowchart showing details of an emergency vehicle notification process performed by an autonomous driving ECU. 5 is a flowchart showing details of a driving change notification process performed by an automatic driving ECU. 4 is a flowchart showing details of a tranquility control process performed by an autonomous driving ECU. 5 is a flowchart showing details of a normal noise notification process executed by an autonomous driving ECU.

Below, several embodiments are described based on the drawings. Note that in each embodiment, corresponding components are given the same reference numerals, and duplicated descriptions may be omitted. When only a portion of the configuration is described in each embodiment, the configuration of the other embodiment described above can be applied to the other portions of the configuration. In addition to the combinations of configurations explicitly stated in the description of each embodiment, configurations of several embodiments can be partially combined together even if not explicitly stated, as long as there is no particular problem with the combination.

First Embodiment
The functions of the vehicle control device according to the first embodiment of the present disclosure are realized by an automatic driving ECU (Electronic Control Unit) 50b shown in Figures 1 and 2. The automatic driving ECU 50b is mounted on a vehicle (hereinafter, the host vehicle Am) together with a driving assistance ECU 50a. The automatic driving ECU 50b and the driving assistance ECU 50a constitute an automatic driving system 50 of the host vehicle Am. By mounting the automatic driving system 50, the host vehicle Am becomes an automatic driving vehicle equipped with an automatic driving function and is capable of traveling by the automatic driving function (autonomous driving control).

The driving assistance ECU 50a is an on-board ECU that realizes driving assistance functions that assist the driver in driving operations in the automated driving system 50. The driving assistance ECU 50a enables advanced driving assistance or partial automated driving at approximately level 2 in the automated driving levels stipulated by the Society of Automotive Engineers. The automated driving performed by the driving assistance ECU 50a is automated driving with a peripheral monitoring obligation that requires the driver to visually monitor the area around the vehicle. For example, driving assistance functions such as ACC (Adaptive Cruise Control), LTC (Lane Trace Control), and LCA (Lane Change Assist) are realized by the driving assistance ECU 50a.

The autonomous driving ECU 50b is an in-vehicle ECU that realizes an autonomous driving function that can take over driving operations from the driver. The autonomous driving ECU 50b is capable of autonomous driving of level 3 or higher, where the system is the main controller. Level 3 autonomous driving performed by the autonomous driving ECU 50b is eyes-off autonomous driving, where the driver is not required to monitor the surroundings and does not need to monitor the area around the vehicle. The autonomous driving ECU 50b may be capable of autonomous driving of level 4 or higher. Level 4 autonomous driving is fully autonomous driving, where all driving tasks are performed by the system, and is brain-off autonomous driving, where the driver is not requested to take over driving.

In the autonomous driving system 50, the control state of the autonomous driving function is switched between multiple states including at least driving assistance control by the driving assistance ECU 50a, which requires monitoring of the surroundings, and autonomous driving control by the autonomous driving ECU 50b, which does not require monitoring of the surroundings. In the following description, autonomous driving control of level 2 or lower by the driving assistance ECU 50a is referred to as "driving assistance control," and autonomous driving control of level 3 or higher by the autonomous driving ECU 50b is referred to as "autonomous driving control."

During the autonomous driving period when the host vehicle Am is driven by the autonomous driving control of the autonomous driving ECU 50b, the driver may be permitted to perform a specific action other than driving that is predefined (hereinafter, the second task). The driver is legally permitted to perform the second task until a request for a change of driving is made by the autonomous driving ECU 50b in cooperation with the HMI (Human Machine Interface) control device 100. For example, actions such as watching entertainment content such as videos, operating devices such as a smartphone, and eating are envisioned as second tasks.

The driving assistance ECU 50a and the autonomous driving ECU 50b are communicatively connected to a communication bus 99 of the in-vehicle network 1 mounted in the host vehicle Am. The in-vehicle monitor device 29, the surroundings monitoring sensor 30, the locator 35, the navigation ECU 38, the in-vehicle communication device 39, the driving control ECU 40, the body ECU 43, and the HMI control device 100 are connected to the communication bus 99. These nodes connected to the communication bus 99 can communicate with each other. Certain nodes among these ECUs etc. may be directly electrically connected to each other and can communicate without going through the communication bus 99.

The in-vehicle monitor device 29 includes multiple in-vehicle cameras that capture images of the interior of the vehicle Am, and a control unit that controls the multiple in-vehicle cameras. The in-vehicle cameras may be visible light cameras, or near-infrared cameras combined with a near-infrared light source. At least one of the multiple in-vehicle cameras is installed so that it can capture an image of the passenger (driver) seated in the driver's seat, and functions as a driver monitor.

The in-vehicle monitor device 29 provides the HMI control device 100 and the automatic driving ECU 50b, etc. with images captured by the vehicle interior camera or the results of image analysis of the captured images as in-vehicle monitor information. The in-vehicle monitor information includes information indicating the number of passengers on board, information on the type of passenger, such as adult, child, elderly, etc., and information indicating the status of each passenger, such as whether they are sleeping or not. Furthermore, the in-vehicle monitor information includes driver status information indicating the position of the driver's eye point and the direction of their line of sight, etc.

The periphery monitoring sensor 30 is an autonomous sensor that monitors the environment surrounding the host vehicle Am. The periphery monitoring sensor 30 includes, for example, one or more of a camera unit, a millimeter wave radar, a lidar, and a sonar. The periphery monitoring sensor 30 is capable of detecting moving objects and stationary objects within a detection range around the host vehicle. The periphery monitoring sensor 30 provides detection information of objects around the host vehicle to the driving assistance ECU 50a and the autonomous driving ECU 50b, etc.

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

The locator 35 further has a map database that stores map data. The map database is mainly 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 shape information of roads and detailed information on each lane. The locator 35 can update the three-dimensional map data and two-dimensional map data to the latest information through external communication using the in-vehicle communication device 39. The locator 35 reads map data around the current position from the map database, and provides it to the driving assistance ECU 50a, the autonomous driving ECU 50b, etc., together with locator information.

The navigation ECU 38 acquires information about the destination specified by the driver or other passengers 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 driving assistance ECU 50a, the automatic driving ECU 50b, 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.

Here, a user terminal such as a smartphone or tablet may be connected to the in-vehicle network 1 or the HMI control device 100. Such a user terminal may provide vehicle position information, direction information, map data, etc. to the driving assistance ECU 50a and the automatic driving ECU 50b, etc., instead of the locator 35. Furthermore, the user terminal may provide route information to the destination to the driving assistance ECU 50a, the automatic driving ECU 50b, the HMI control device 100, etc., instead of the navigation ECU 38. The user terminal may also play video content, etc., instead of the HMI system 10 described below, or together with the HMI system 10.

The in-vehicle communication device 39 is an external communication unit mounted on the vehicle Am and 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, etc. 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 signal information indicating the lighting pattern of a traffic light, as well as detection information of stopped vehicles, parked vehicles, pedestrians, cyclists, etc. from the roadside device. The in-vehicle communication device 39 provides the received congestion information, traffic regulation information, signal information, detection information, etc. to the navigation ECU 38, the autonomous driving ECU 50b, the HMI control device 100, etc.

The driving control ECU 40 is an electronic control device that mainly includes a microcontroller. The driving control ECU 40 generates vehicle speed information indicating the current driving speed of the vehicle Am based on the detection signals of wheel speed sensors installed in the hub portion of each wheel, and sequentially outputs the generated vehicle speed information to the communication bus 99. The driving control ECU 40 has at least the functions of a brake control ECU, a drive control ECU, and a steering control ECU. The driving control ECU 40 continuously performs braking force control for each wheel, output control of the power generation device 41, and steering angle control based on one of the operation commands based on the driver's driving operation, the control commands of the driving assistance ECU 50a, and the control commands of the automatic driving ECU 50b.

The power generating device 41 is mounted on the host vehicle Am and generates power for propelling the host vehicle Am. As an example, the power generating device 41 is a hybrid power unit that includes multiple power sources, such as an internal combustion engine that burns fuel such as gasoline or diesel, and a motor generator for driving. The power generating device 41 may include only one of the internal combustion engine and the motor generator, in other words, may be configured mainly based on a single power source.

The cruise control ECU 40 switches the drive mode of the host vehicle Am based on the operation information acquired from the HMI control device 100. The cruise control ECU 40 has normal mode, eco mode, comfort mode, sport mode, etc. preset as drive mode options. The cruise control ECU 40 changes the driving characteristics of the host vehicle Am based on the switching of the drive mode. The eco mode is a drive mode that prioritizes fuel efficiency or electricity consumption over the standard normal mode. The comfort mode is a drive mode that prioritizes ride comfort over the normal mode. The sport mode is a drive mode that prioritizes driving performance over the normal mode. The state of the drive mode set in the cruise control ECU 40 is notified to the driver by switching the display mode by the HMI control device 100. For example, when the drive mode is the sport mode, a tachometer is displayed on the meter display 21.

The body ECU 43 is an electronic control device that mainly includes a microcontroller. The body ECU 43 has the function of controlling various on-board devices installed in the host vehicle Am. A power window (hereinafter, PW) actuator 44 is connected to the body ECU 43 as one of the various on-board devices. The body ECU 43 controls the operation of the PW actuator 44 based on a user operation input to a power window switch provided on the door of the host vehicle Am, and opens and closes (raises and lowers) the side window of the host vehicle Am.

The HMI control device 100 constitutes the HMI system 10 together with multiple display devices, an audio device 24, an ambient light 25, an operation device 26, and an in-vehicle acoustic sensor 27. The HMI system 10 has an input interface function that accepts operations by passengers such as the driver of the vehicle Am, and an output interface function that presents information to the driver.

The display devices present information to the driver's vision through image display, etc. The display devices include a meter display 21, a center information display (hereafter, CID) 22, and a head-up display (hereafter, HUD) 23, etc. The CID 22 has a touch panel function and detects touch operations on the display screen by the driver, etc.

The audio device 24 has multiple speakers installed in the vehicle cabin. The audio device 24 reproduces notification sounds or voice messages, etc., in the vehicle cabin through the speakers. The ambient lights 25 are provided on the instrument panel, steering wheel, etc. The ambient lights 25 present information using the driver's peripheral vision through an ambient display that changes the light color.

The operation device 26 is an input unit that accepts user operations by the driver, etc. User operations related to starting and stopping the automatic driving function, and user operations related to setting a destination for route guidance, for example, are input to the operation device 26. In addition, user operations related to the implementation of noise reduction control, which will be described later, are input to the operation device 26. 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 driver is saying.

The interior acoustic sensor 27 is mainly composed of a microphone element such as a MEMS microphone or a condenser microphone. The interior acoustic sensor 27 detects sounds occurring within the vehicle cabin by converting vibrations in the air within the vehicle cabin into an electrical signal using the microphone element. The interior acoustic sensor 27 mainly detects noise transmitted from outside the vehicle to the interior of the vehicle. Multiple interior acoustic sensors 27 may be provided within the vehicle cabin so that noise from multiple locations within the vehicle cabin can be detected.

The HMI control device 100 is a computer that mainly includes a control circuit equipped with a processing unit 11, RAM 12, storage unit 13, 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 multiple display devices, an audio device 24, ambient light 25, etc. The HMI control device 100 presents information related to autonomous driving in cooperation with the autonomous driving system 50. For example, when the autonomous driving ECU 50b plans to end autonomous driving control, the HMI control device 100 issues a notification requesting the driver to take over driving.

The HMI control device 100 acquires operation information indicating the content of user operations from the CID 22 and the operation device 26, etc. The HMI control device 100 provides operation information of user operations related to the autonomous driving function, and information related to noise inside the vehicle cabin detected by the interior acoustic sensor 27 (hereinafter, interior noise information), etc., to the autonomous driving ECU 50b. The HMI control device 100 also provides operation information of a user operation for setting the destination of the host vehicle Am to the navigation ECU 38.

The HMI control device 100 has a function for playing content such as videos and music, as well as a noise canceling function and a noise masking function. The HMI control device 100 is provided with a noise canceling control unit 81 for implementing the noise canceling function, and an onomatopoeia generating unit 82 for implementing the noise masking function. The noise canceling control unit 81 and the onomatopoeia generating unit 82 may be configured to output sound into the vehicle cabin using the speaker of the audio device 24, or may be configured to output sound into the vehicle cabin using a dedicated speaker.

The noise canceling control unit 81 and the onomatopoeia generation unit 82 acquire the waveform of noise inside the vehicle cabin detected by the interior acoustic sensor 27. The noise canceling control unit 81 outputs sound waves with a waveform that is in opposite phase to the noise from the speaker into the vehicle cabin. The noise canceling control unit 81 reduces the noise inside the vehicle cabin by canceling out at least a portion of the noise with the opposite phase sound waves. The onomatopoeia generation unit 82 also analyzes the waveform of the noise and generates onomatopoeia with a frequency and volume that makes the noise difficult for the passengers to hear. The onomatopoeia generation unit 82 outputs the generated onomatopoeia from the speaker into the vehicle cabin, and by covering up the noise with the onomatopoeia, the noise inside the vehicle cabin as perceived by the passengers is reduced.

Next, we will explain the details of the automatic driving ECU 50b in more detail.

The autonomous driving ECU 50b has a higher computing capacity than the driving assistance ECU 50a and can at least perform driving control equivalent to ACC, LTC, and LCA. The autonomous driving ECU 50b may be able to perform driving assistance control in which the driver is required to monitor the surroundings, in place of the driving assistance ECU 50a, in situations where the autonomous driving control is temporarily interrupted.

The autonomous driving ECU 50b is a computer that mainly includes a control circuit equipped with a processing unit 51, RAM 52, storage unit 53, input/output interface 54, and a bus connecting these. The processing unit 51 accesses the RAM 52 to execute various processes (instructions) for implementing the autonomous driving control method and vehicle control method according to the present disclosure. The storage unit 53 stores various programs (autonomous driving control program, vehicle control program, etc.) executed by the processing unit 51. By executing the programs by the processing unit 51, the autonomous driving ECU 50b is configured with an information linkage unit 61, an environment recognition unit 62, an action determination unit 63, a control execution unit 64, an equipment control unit 65, etc. as functional units for implementing the autonomous driving function and the vehicle control function (see FIG. 2).

The information linking unit 61 provides information to the HMI control device 100 and acquires information from the HMI control device 100 and the in-vehicle monitor device 29. The information linking unit 61 has an HMI information acquisition unit 71, an alert request unit 72, and an in-vehicle monitoring unit 73 as sub-functional units for information linking with the HMI control device 100 and the in-vehicle monitor device 29.

The HMI information acquisition unit 71 grasps the contents of user operations input to the CID 22 and the operation device 26 by the driver or the like based on the operation information acquired from the HMI control device 100. The HMI information acquisition unit 71 grasps, for example, a level 2 transition operation that instructs a transition from manual driving to driving assistance control, and a level 3 transition operation that instructs a transition from driving assistance control to autonomous driving control. The HMI information acquisition unit 71 also grasps an approval operation that approves the implementation of noise reduction control, which will be described later. In addition, the HMI information acquisition unit 71 grasps the status of content playback by the audio device 24.

The notification request unit 72 enables the HMI control device 100 to issue a notification synchronized with the operating state of the autonomous driving function by outputting a request to issue a notification to the HMI control device 100. For example, when the end of autonomous driving control is scheduled, the notification request unit 72 outputs a request to issue a notification requesting a change of driving to the HMI control device 100. The notification request unit 72 also outputs a request to issue a notification related to noise reduction control, which will be described later, to the HMI control device 100.

The interior monitoring unit 73 monitors the situation inside the vehicle cabin using the interior monitor information obtained from the interior monitor device 29 and the interior noise information obtained from the HMI control device 100. Specifically, the interior monitoring unit 73 continuously monitors the driver's driving posture, line of sight, whether or not surrounding monitoring is being performed, whether or not a second task is being performed, and the level of alertness. Furthermore, the interior monitoring unit 73 detects any abnormalities in the driver's physical condition. In addition, based on the interior monitor information, the interior monitoring unit 73 determines whether or not there is a specific type of passenger in the vehicle cabin for whom silencing by the silencing control described below is useful, such as a child or a sleeping passenger. Note that the passengers for whom silencing is useful are not limited to the above-mentioned children and sleeping passengers, and may be changed as appropriate.

The environment recognition unit 62 recognizes the driving environment of the host vehicle Am by combining the locator information and map data obtained from the locator 35 with the detection information obtained from the surrounding monitoring sensor 30 and the in-vehicle communication device 39. The environment recognition unit 62 obtains vehicle speed information indicating the current driving speed from the communication bus 99 as information indicating the state of the host vehicle Am.

The environment recognition unit 62 has a target recognition unit 74 and a road recognition unit 75 as sub-functional units for recognizing the driving environment. The target recognition unit 74 recognizes the relative positions and relative speeds of dynamic targets around the vehicle, such as other vehicles traveling around the vehicle Am. The target recognition unit 74 recognizes the approach of emergency vehicles, such as police vehicles, fire engines, and ambulances, to the vehicle Am. The road recognition unit 75 acquires road information related to the roads on which the vehicle Am is traveling or is scheduled to travel. The environment recognition unit 62 sequentially provides the information recognized by the target recognition unit 74 and the road recognition unit 75, i.e., the recognition results of the driving environment, to the action determination unit 63.

The behavior determination unit 63 cooperates with the driving assistance ECU 50a and the HMI control device 100 to control the autonomous driving system 50 and the driver's handover of driving. When the autonomous driving ECU 50b 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 results of the recognition of the driving environment by the environment recognition unit 62, and outputs the generated planned driving line to the control execution unit 64. The behavior determination unit 63 has a control switching unit 76 and an evacuation control unit 77 as sub-functional units for controlling the operating state of the autonomous driving function.

The control switching unit 76 cooperates with the driving assistance ECU 50a to switch the driving control state of the host vehicle Am among manual driving (control off), level 2 driving assistance control in which the driver is obligated to monitor the surroundings, and level 3 autonomous driving control in which the driver is not obligated to monitor the surroundings. When the control switching unit 76 switches the driving control state of the host vehicle Am using the automatic driving function, it grasps the current driving control state after switching. The control switching unit 76 provides control state information indicating the current driving control state to the information linking unit 61, etc. The control state information is provided to the HMI control device 100, etc. via the information linking unit 61.

The evacuation control unit 77 performs emergency evacuation control based on the occurrence of an abnormality related to the vehicle Am. The emergency evacuation control is vehicle control that stops the vehicle Am at an evacuation location. The evacuation location is set within the lane in which the vehicle is traveling or on the side of the road (shoulder) of the road in which the vehicle is traveling. The evacuation control unit 77 may be able to set the evacuation location in an emergency parking lane, a roadside strip, a parking area, etc. The evacuation control unit 77 decides to implement emergency evacuation control when the in-vehicle monitoring unit 73 detects an abnormality in the driver's physical condition or when the target recognition unit 74 detects the approach of an emergency vehicle.

When the autonomous driving ECU 50b has control of driving operations, the control execution unit 64 cooperates with the cruise control ECU 40 to execute acceleration/deceleration control and steering control of the host vehicle Am according to 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.

The device control unit 65 controls the operation of various in-vehicle devices mounted on the vehicle Am in association with the operation of the autonomous driving function by outputting control commands to the body ECU 43. The device control unit 65 cooperates with the body ECU 43 and controls the PW actuator 44 to adjust the open/closed state of each window of the vehicle Am during the autonomous driving period.

[Noise reduction control during Level 3 autonomous driving]
In the autonomous vehicle described above, the driver does not perform driving operations or monitor the surroundings during the autonomous driving period. At this time, the autonomous driving system 50 may perform control to increase the rotation speed of the internal combustion engine or motor generator of the power generating device 41, for example, when accelerating to a set vehicle speed for autonomous driving control. In such a situation, passengers who are not participating in driving may feel uneasy about whether the autonomous driving is being controlled correctly due to noise in the vehicle cabin caused by the operation of the internal combustion engine or motor generator.

Therefore, the action determination unit 63 of the autonomous driving ECU 50b is further provided with a noise reduction control unit 78 as a sub-functional unit based on the vehicle control program. During the autonomous driving period when the host vehicle Am is driving by autonomous driving control, the noise reduction control unit 78 performs noise reduction control to reduce noise in the cabin of the host vehicle Am, rather than during the monitoring period when the driver is obligated to monitor the surroundings. The monitoring period includes the period when the host vehicle Am is driving by driving assistance control including hands-on control or hands-off control, and the period when the host vehicle Am is driving by manual driving. The noise reduction control unit 78 performs power control and cabin control as noise reduction control. Details of the power control and cabin control, and details of notifications related to the noise reduction control are explained below.

<Power control for noise reduction>
The power control is vehicle control that suppresses vibrations of the power generation device 41 that cause noise in the vehicle cabin. The noise reduction control unit 78 cooperates with the control execution unit 64 and the driving control ECU 40 to implement power selection control and power reduction control as power control for noise reduction.

Power selection control is vehicle control that, when the power generating device 41 mounted on the vehicle Am includes multiple power sources such as an internal combustion engine and a motor generator, gives priority to operating a quiet power source (i.e., a motor generator) that produces less noise among the multiple power sources. As power selection control, the quiet control unit 78 stops the internal combustion engine and runs the vehicle Am in so-called EV mode using the power generated by the motor generator. When the power generating device 41 includes multiple (two) motor generators for driving, the quiet control unit 78 may, as power selection control, operate only the motor generator that produces less vibration and noise among the multiple motor generators.

Power suppression control is vehicle control that suppresses the rotational speed (rpm) of the internal combustion engine or motor generator included as a power source in the power generation device 41. The silent control unit 78 realizes power suppression control by applying shift control that shifts up at a low rotational speed, or acceleration control that suppresses acceleration to a low level, etc.

When the evacuation control unit 77 performs emergency evacuation control due to the approach of an emergency vehicle, the silent control unit 78 suspends the power selection control and the power suppression control. Furthermore, when the evacuation control unit 77 performs emergency evacuation control due to the occurrence of a driver abnormality, the silent control unit 78 judges whether the power selection control and the power suppression control hinder the emergency evacuation control. When the silent control unit 78 judges that the power selection control and the power suppression control do not hinder the emergency evacuation control, the silent control unit 78 performs (continues) the power selection control and the power suppression control even during the evacuation travel period in which the host vehicle Am travels due to the emergency evacuation control. On the other hand, when it is judged that the emergency evacuation control is hindered, the silent control unit 78 suspends the power selection control and the power suppression control during the evacuation travel period. For example, when emergency evacuation control that requires acceleration or maintaining a high speed, such as when a lane change is required to move to an evacuation location, is planned, the power selection control and the power suppression control are suspended.

The silent control unit 78 can relax the power suppression control. Specifically, when content is being played by the audio device 24 inside the vehicle, the silent control unit 78 relaxes the power suppression control. The louder the content playback volume becomes, the more the silent control unit 78 relaxes the power suppression control, allowing the internal combustion engine or motor generator to operate at a high rotational speed.

In addition, if implementing power suppression control would cause the driving speed of the host vehicle Am to fall short of a high set vehicle speed (e.g., 200 km/h) set by the driver, the silence control unit 78 relaxes the power suppression control until the set vehicle speed is reached. After reaching the set vehicle speed, the silence control unit 78 determines whether the set vehicle speed can be maintained even if relaxation of the power suppression control is ended. If the set vehicle speed can be maintained, the silence control unit 78 ends relaxation of the power suppression control. On the other hand, if the set vehicle speed cannot be maintained, the silence control unit 78 continues easing of the power suppression control, allowing cruising at the set vehicle speed.

<In-vehicle control for noise reduction>
The vehicle interior control is a vehicle control for reducing noise occurring in the vehicle interior or for making the noise difficult to hear. The silent control unit 78 cooperates with the information linkage unit 61 and the HMI control device 100, or with the device control unit 65 and the body ECU 43, and performs volume adjustment control, noise canceling control, noise masking control, and opening and closing control as vehicle interior control for silent operation.

Volume adjustment control is control to increase the volume of content being played by the audio device 24 in the vehicle cabin. When content is being played by the audio device 24, the silence control unit 78 cooperates with the notification request unit 72 to request the HMI control device 100 to gradually increase the volume of the content being played. As volume adjustment control, the HMI control device 100 raises the volume of the audio device 24 by a predetermined level. Based on the end of the volume adjustment control, the HMI control device 100 lowers the volume of the audio device 24 to the level before the control started.

As described above, noise canceling control is a control that reproduces within the vehicle cabin a sound with a waveform that is in the opposite phase to the noise. The noise canceling control unit 81 adjusts the degree of noise canceling effect for each passenger in the vehicle cabin. Specifically, the noise canceling control unit 81 makes the noise canceling effect for the driver sitting in the driver's seat lower than the noise canceling effect for passengers sitting in other seats. In other words, noise in the passenger seat is reduced more than noise in the driver's seat.

As described above, noise masking control is a control that reproduces onomatopoeia in the vehicle cabin to cover up noise. In response to a request from the notification request unit 72, the onomatopoeia generating unit 82 outputs onomatopoeia that makes noise in the vehicle cabin less audible to the occupants, thereby reducing the noise felt by the occupants, including the driver.

Opening and closing control is a control that adjusts the open/closed state of the windows provided on the vehicle Am in order to make the interior of the vehicle quieter. For example, when a particular window is wide open, or when only one window is open, noise associated with driving is likely to occur. In response to a request from the equipment control unit 65, the body ECU 43 adjusts the open/closed state of each window while maintaining a balance between the left and right so that the interior of the vehicle is not noisy. In principle, the body ECU 43 controls to close each window. As an opening and closing control, the body ECU 43 may also adjust all windows to be fully closed.

<Notification related to noise reduction control>
The notification request unit 72 cooperates with the HMI control device 100 to issue a notification (hereinafter, inquiry notification) to inquire of the driver whether or not to implement noise reduction control. The inquiry notification as to whether or not noise reduction control is required is issued before the driver starts the second task based on switching from driving assistance control or the like to autonomous driving control. Specifically, the HMI control device 100 issues an inquiry notification using the CID 22 on which video content or the like related to the second task is displayed, before playback of the video content or the like is started. If the driver approves the implementation of noise reduction control in response to the inquiry notification, the noise reduction control unit 78 implements noise reduction control.

[Processes related to noise reduction control]
Next, in order to realize the noise reduction control described above, the details of the mode switching process, power control process, window control process, and vehicle interior control process performed by the autonomous driving system 50 will be further explained based on Figures 3 to 6 and with reference to Figures 1 and 2.

<Mode switching process>
3 is a process for switching between a silent mode in which silent control is performed and a normal mode in which silent control is not performed. The mode switching process is started by the autonomous driving ECU 50b when the control switching unit 76 switches the control state (autonomous driving level) of the autonomous driving function.

In S11 of the mode switching process, the control execution unit 64 determines the current drive mode set in the driving control ECU 40. In S12, the silence control unit 78 determines whether the current drive mode is set to a sports mode that prioritizes driving performance. If the drive mode is set to the sports mode (S12: YES), the silence control unit 78 sets the drive mode to a normal mode in which silence control is not performed in S19. As a result, when a tachometer is displayed on the meter display 21, silence control is not performed.

On the other hand, if the drive mode is set to a mode other than the sport mode (S12: NO), the control switching unit 76 determines in S13 the driving control state of the host vehicle Am, i.e., the current autonomous driving level. As an example, when a control transition to real-world driving control has been performed, the control switching unit 76 determines in S13 that the driving control state of the host vehicle Am has been switched to a state in which the vehicle is driven by autonomous driving control.

In S14, the control switching unit 76 determines whether the driving control state of the host vehicle Am is at autonomous driving level 3 or higher. If the driving control state of the host vehicle Am is below level 3 (S14: NO), the silencing control unit 78 sets the driving control state of the host vehicle Am to a normal mode in which silencing control is not performed in S19. On the other hand, if the driving control state of the host vehicle Am is at level 3 or higher (S14: YES), the interior monitoring unit 73 grasps the situation inside the vehicle based on the interior monitor information and interior noise information in S15. The interior monitoring unit 73 grasps at least the type of occupant in the vehicle cabin in S15.

In S16, the interior monitoring unit 73 determines whether or not a specific type of passenger for whom noise reduction is useful is present in the vehicle cabin. If a specific type of passenger, such as a child or a sleeping passenger, is present in the vehicle cabin (S16: YES), the noise reduction control unit 78 sets the vehicle to a noise reduction mode in which noise reduction control is performed in S20. On the other hand, if a specific type of passenger is not present in the vehicle cabin (S16: NO), the notification request unit 72 issues an inquiry notification based on switching to autonomous driving control in S17.

In S18, the HMI information acquisition unit 71 determines whether operation information of a user operation approving the implementation of noise reduction control has been acquired from the HMI control device 100. If the HMI information acquisition unit 71 has acquired operation information (S18: YES), i.e., if the implementation of noise reduction control has been approved by the driver, the noise reduction control unit 78 sets the noise reduction mode in which noise reduction control is implemented in S20. On the other hand, if operation information is not acquired within a predetermined time (S18: NO), i.e., if the implementation of noise reduction control has not been approved by the driver, the noise reduction control unit 78 sets the normal mode in which noise reduction control is not implemented in S19.

<Power control processing>
The power control process shown in Fig. 4 is a process for switching between execution and stop of the power selection control and the power suppression control. The power control process is repeatedly performed by the automatic driving ECU 50b during the automatic driving period.

In S31 of the power control process, the silence control unit 78 determines the control mode that was set in the mode switching process (see FIG. 3). In S32, the silence control unit 78 determines whether the control mode is set to the silence mode. If the control mode is set to the normal mode (S32: NO), in S37, the silence control unit 78 turns off the silence control (power control) including the power selection control and the power suppression control.

On the other hand, if the control mode is set to the silent mode (S32: YES), in S33 the target recognition unit 74 recognizes the approach of an emergency vehicle to the host vehicle Am. If the approach of an emergency vehicle is recognized (S33: YES), the silent control unit 78 turns off the silent control in S37. This causes the power suppression control and the like to be stopped. On the other hand, if an emergency vehicle is not approaching the host vehicle Am (S33: NO), the silent control unit 78 determines in S34 whether or not emergency evacuation control is being performed.

If emergency evacuation control is being performed (S34: YES), the silence control unit 78 (behavior determination unit 63) determines in S35 whether or not power control for noise reduction interferes with emergency evacuation control. If it is determined that power control may interfere with emergency evacuation control (S35: YES), the silence control unit 78 turns off noise reduction control including power selection control and power suppression control in S37. On the other hand, if emergency evacuation control is not being performed (S34: NO), or if it is determined that power control is not likely to interfere with emergency evacuation control (S35: NO), the silence control unit 78 turns on noise reduction control in S36. This allows the implementation of power selection control, which preferentially operates the motor generator that produces less noise, and power suppression control, which suppresses the rotation speed of the power generation device 41.

In S38, the behavior determination unit 63 determines whether the traveling speed of the host vehicle Am reaches the set speed while the power suppression control is being implemented. If implementing the power suppression control would cause the traveling speed of the host vehicle Am to not reach the set vehicle speed (S38: YES), the silence control unit 78 relaxes the power suppression control in S40. In this case, the power selection control may also be interrupted. The silence control unit 78 continues to relax at least the power suppression control until the traveling speed of the host vehicle Am reaches the set vehicle speed.

If the driving speed of the vehicle Am reaches the set vehicle speed even when power suppression control is implemented (S38: NO), in S39, the HMI information acquisition unit 71 grasps the state of content playback by the audio device 24 in the vehicle cabin. If content playback is occurring in the vehicle cabin (S39: YES), the silence control unit 78 relaxes the power suppression control in S40. In this case, the power suppression control may be turned off. On the other hand, if content playback is not occurring in the vehicle cabin (S39: NO), the silence control unit 78 stops relaxing the power suppression control in S41.

<Window control processing>
5 is a process for adjusting the open/closed state of the window in order to reduce noise inside the vehicle cabin by performing an open/close control. The window control process is repeatedly performed by the autonomous driving ECU 50b during the autonomous driving period.

In S51 of the window control process, the silence control unit 78 determines the control mode set in the mode switching process (see FIG. 3). In S52, the silence control unit 78 determines whether the control mode has been switched to the silence mode. If the control mode has not been switched to the silence mode (S52: NO), the window control process ends. In contrast, if the control mode has been switched to the silence mode (S52: YES), in S53, the silence control unit 78 determines the open/closed state of the windows provided on the vehicle Am through the device control unit 65 and the body ECU 43. Furthermore, in S54, the silence control unit 78 cooperates with the device control unit 65 and the body ECU 43 to control the opening and closing of the windows to reduce noise inside the vehicle.

<In-vehicle control processing>
6 is a process for controlling the execution of vehicle interior control in cooperation with the HMI control device 100. The vehicle interior control process is repeatedly performed by the autonomous driving ECU 50b during the autonomous driving period.

In S61 of the vehicle interior control process, the silent control unit 78 determines the control mode that was set in the mode switching process (see FIG. 3). In S62, the silent control unit 78 determines whether the control mode has been switched to the silent mode. If the control mode has not been switched to the silent mode (S62: NO), the vehicle interior control process ends.

In contrast, if there has been a switch to the silent mode (S62: YES), in S63, the behavior determination unit 63 determines whether the traveling speed of the host vehicle Am will reach the set speed with the power suppression control being implemented. If the traveling speed of the host vehicle Am will not reach the set vehicle speed if the power suppression control is implemented (S63: YES), in S64, the notification request unit 72 cooperates with the HMI control device 100 to issue a notification indicating that the set vehicle speed will not be reached as a warning of insufficient vehicle speed. The warning of insufficient vehicle speed in S64 may be issued even when the power suppression control is relaxed (see S40 in FIG. 4).

Furthermore, the silent control unit 78 cooperates with the notification request unit 72 and the HMI control device 100 to perform volume adjustment control (S65), noise canceling control (S66), and noise masking control (S67). The order in which each control is performed may be changed as appropriate. In addition, some controls may not be performed.

(Summary of the first embodiment)
In the first embodiment described above, during the automatic driving period in which the host vehicle Am is driven by the autonomous driving control, the noise reduction control is performed to reduce noise in the vehicle cabin of the host vehicle Am. Therefore, in a driving state in which the driver is not monitoring the surroundings, it is possible to suppress the anxiety that a passenger who is not involved in driving feels about the autonomous driving control due to noise in the vehicle cabin caused by driving.

In addition, in the first embodiment, power suppression control that suppresses the rotation speed of the power generating device 41 mounted on the vehicle Am is implemented as noise reduction control. Such power suppression control can effectively reduce noise inside the vehicle cabin that occurs during driving. As a result, the anxiety of passengers can be further suppressed.

In addition, in the first embodiment, the state of content playback by the audio device 24 in the vehicle cabin is grasped, and if content playback is occurring in the vehicle cabin, the power suppression control is relaxed. If media content is being played in the vehicle cabin, passengers are less likely to feel uneasy even if the interior of the vehicle is a little noisy. Therefore, the power suppression control may be relaxed to allow the interior of the vehicle to become noisy.

Furthermore, in the first embodiment, the approach of an emergency vehicle to the host vehicle Am is detected. Then, when the approach of an emergency vehicle is detected, the power suppression control is stopped. Therefore, driving control to avoid the emergency vehicle can be quickly implemented without being hindered by the power suppression control.

Furthermore, in the first embodiment, when emergency evacuation control is implemented based on the occurrence of an abnormality related to the host vehicle Am, the silent control unit 78 judges whether or not the power suppression control will interfere with the emergency evacuation control. Then, when it is determined that the power suppression control will not interfere with the emergency evacuation control, the power suppression control is implemented during the evacuation driving period in which the host vehicle Am is driven by the emergency evacuation control. As a result, the interior of the vehicle is silent during the evacuation driving period because the power generating device 41 is prevented from rotating at high speed. As a result, it is possible to provide a sense of security to passengers even during the evacuation driving period.

In addition, in the first embodiment, if the driving speed of the vehicle Am would not reach the set vehicle speed set by the driver if power suppression control were to be implemented, a notification is given indicating that the set vehicle speed will not be reached. This notification allows the passenger to correctly understand the control state of the vehicle Am. As a result, the passenger's anxiety about the autonomous driving control can be reduced.

In addition, in the first embodiment, if the driving speed of the vehicle Am would not reach the set vehicle speed set by the driver if power suppression control were implemented, the power suppression control is relaxed until the set vehicle speed is reached. Therefore, in a scene where high-speed cruising is required, a situation in which passengers are likely to feel uneasy about the autonomous driving control due to a lack of vehicle speed caused by power suppression control can be avoided.

In addition, in the first embodiment, the volume adjustment control that increases the volume of the content being played by the audio device 24 in the vehicle cabin is implemented as noise reduction control. As a result, the passengers' attention is directed to the sound of the content, so that the passengers are less likely to notice the noise in the vehicle cabin.

In the first embodiment, noise canceling control using a noise canceling control unit 81 that suppresses noise inside the vehicle cabin is implemented as silencing control. In this noise canceling control, noise from the passenger seat where passengers other than the driver are seated is reduced more than noise from the driver's seat where the driver is seated. This allows the driver to understand the operating state of the power generating device 41 from the sound information. Meanwhile, passengers can spend time in a quiet environment where noise has been cancelled. Note that noise canceling control corresponds to "noise reduction control."

Furthermore, in the first embodiment, it is determined whether or not a particular type of passenger for whom noise reduction is useful, specifically a child or a sleeping passenger, is present in the vehicle cabin. Then, if such a passenger is present in the vehicle cabin, noise reduction control is implemented. Therefore, it is possible to avoid a situation in which noise in the vehicle cabin makes children or sleeping passengers uncomfortable.

In addition, in the first embodiment, a sound dummy device that outputs dummy sounds that make noises inside the vehicle cabin less audible to passengers is used for noise reduction control. In this way, the noise felt by passengers can be reduced by generating dummy sounds that erase abnormal sounds and masking the noise. As a result, it is possible to reduce the anxiety of passengers.

In the first embodiment, the noise reduction control is an opening/closing control that adjusts the open/closed state of the windows provided on the vehicle Am to reduce noise inside the vehicle cabin. This opening/closing control makes it possible to suppress noise that is generated by opening the windows too far or by opening only one window.

Furthermore, in the first embodiment, based on the switch to autonomous driving control, a notification is issued to inquire of the driver whether or not to implement noise reduction control. Then, if the implementation of noise reduction control is approved by the driver, noise reduction control is implemented. Therefore, during the autonomous driving period, in scenes where noise reduction is not required, it is possible to avoid the implementation of noise reduction control based on the intention of the driver or other passengers.

In addition, in the first embodiment, when the power generating device 41 mounted on the vehicle Am includes multiple power sources, the power selection control is implemented as noise reduction control. In this power selection control, the quiet power source that generates the least noise among the multiple power sources, i.e., the motor generator, is operated preferentially. This control can also effectively reduce noise inside the vehicle cabin caused by the operation of the power generating device 41.

In addition, in the first embodiment, when the drive mode of the vehicle Am is set to a sports mode that prioritizes driving performance, the implementation of noise reduction control during the automatic driving period is stopped. As a result, when the driver wishes to drive aggressively, it is possible to avoid a situation in which noise reduction is implemented against the driver's will.

In the first embodiment, the autonomous driving ECU 50b corresponds to the "vehicle control device", the HMI information acquisition unit 71 corresponds to the "playback recognition unit", the notification request unit 72 corresponds to the "notification implementation unit", and the in-vehicle monitoring unit 73 corresponds to the "in-vehicle recognition unit". In addition, the object recognition unit 74 corresponds to the "exterior recognition unit", the control switching unit 76 corresponds to the "control recognition unit", the noise canceling control unit 81 corresponds to the "noise suppression device", and the onomatopoeia generating unit 82 corresponds to the "onomatopoeia device".

Second Embodiment
The second embodiment of the present disclosure is a modified example of the first embodiment. In the second embodiment, the content of the acoustic control in the vehicle cabin performed by the cooperation of the HMI control device 100 and the automatic driving ECU 50b is different from that in the first embodiment. Hereinafter, the details of the HMI control device 100 and the automatic driving ECU 50b of the second embodiment will be described with reference to FIG.

The HMI control device 100 has a function for playing content such as videos and music, as well as a background sound output function and a sound field control function. The HMI control device 100 is provided with a BGM (background music) output unit 86 for implementing the background sound output function, and a sound field control unit 87 for implementing the sound field control function. The BGM output unit 86 and the sound field control unit 87 may be configured to output sound into the vehicle cabin using the speakers of the audio device 24, or may be configured to output sound into the vehicle cabin using dedicated speakers.

The BGM output unit 86 generates audio signals for outputting the automatic driving BGM, driving assistance BGM, and driving changeover BGM into the cabin of the vehicle Am. The BGM output unit 86 outputs the generated audio signals to the audio device 24. The audio device 24 plays each BGM using a speaker according to the input audio signal.

Autonomous driving BGM is background sound that indicates that autonomous driving control is being performed. Driving assistance BGM is background sound that indicates that driving assistance control is being performed. Autonomous driving BGM and driving assistance BGM are set for each autonomous driving level. That is, when the autonomous driving ECU 50b is capable of performing autonomous driving levels 4 and 3, the BGM output unit 86 is provided with autonomous driving BGM corresponding to autonomous driving level 4 and autonomous driving BGM corresponding to autonomous driving level 3. Furthermore, driving assistance BGM corresponding to autonomous driving level 2 and driving assistance BGM corresponding to autonomous driving level 1 are provided in the BGM output unit 86.

The autonomous driving BGM and driving assistance BGM use melodies that represent the individual company brands, such as the vehicle manufacturer that produces the vehicle Am, or the company that provides mobility services using the vehicle Am. The autonomous driving BGM and driving assistance BGM linked to each autonomous driving level are similar but different from each other. Specifically, each BGM has a different pitch or tempo. As an example, the higher the autonomous driving level, the lower the pitch of the BGM is set. Also, the higher the autonomous driving level, the faster the tempo of the BGM is set.

Here, if the autonomous driving ECU 50b is capable of remote autonomous driving, the BGM output unit 86 may be prepared with autonomous driving BGM corresponding to remote autonomous driving. The BGM output unit 86 may also be prepared with separate driving assistance BGM corresponding to hands-off level 2 and driving assistance BGM corresponding to hands-on level 2. Furthermore, the higher the autonomous driving level, the higher the pitch of the BGM may be set. Similarly, the higher the autonomous driving level, the slower the tempo of the BGM may be set.

The driving change BGM is a change notification background sound that notifies the driver of a change in driving control state (autonomous driving level) from autonomous driving control to driving assistance control. The driving change BGM is output as a notice before the driving control state is changed. The driving change BGM may also be output as a change completion notification after the driving control state is changed. The driving change BGM may be BGM separate from the autonomous driving BGM and driving assistance BGM, or it may be the autonomous driving BGM or driving assistance BGM linked to the changed driving control state.

The sound field control unit 87 uses multiple speakers connected to the audio device 24 to create a sound field in the vehicle cabin where sound appears to be coming from a location where no sound source actually exists. Based on commands obtained from the autonomous driving ECU 50b, the sound field control unit 87 determines in three dimensions the virtual position of the source of sound to be output into the vehicle cabin. Based on modeling data such as the sound propagation characteristics from each speaker and the reflection pattern in the vehicle cabin, the sound field control unit 87 performs signal processing corresponding to the virtual sound source position on the audio signal to be output. The sound field control unit 87 outputs the audio signal to which the signal processing has been applied to the audio device 24 and reproduces it through each speaker. The sound field control unit 87 can perform signal processing on audio signals of content such as video and music, audio signals of each BGM generated by the BGM output unit 86, and audio signals of onomatopoeia generated by the onomatopoeia generation unit 82. The sound field control unit 87 determines the number and positions of passengers in the vehicle cabin and adjusts the virtual sound source position according to the number and positions of passengers.

The autonomous driving ECU 50b uses the functions of the HMI control device 100 to output background sounds related to autonomous driving, control the interior of the vehicle to reduce noise, and issue normal notifications after noise is generated. The details of these functions are explained below in order.

<Output of background sounds related to autonomous driving>
The notification request unit 72 cooperates with the BGM output unit 86 to play the autonomous driving BGM and driving assistance BGM in the vehicle cabin. As described above, the control switching unit 76 grasps the autonomous driving level linked to the driving control state currently being executed. The notification request unit 72 switches the autonomous driving BGM and driving assistance BGM to be output according to the autonomous driving level currently being executed grasped by the control switching unit 76, and changes the mode of the BGM to be played in the vehicle cabin.

Specifically, when autonomous driving ECU 50b starts autonomous driving control equivalent to autonomous driving level 3, the notification request unit 72 outputs autonomous driving BGM indicating that autonomous driving control is being performed after the start of autonomous driving control (see FIG. 8). The notification request unit 72 may start outputting autonomous driving BGM after an autonomous driving start notification that notifies the start of autonomous driving, or may start outputting autonomous driving BGM substantially simultaneously with the autonomous driving start notification. In these cases, the autonomous driving start notification is a text message displayed on the meter display 21 or HUD 23, etc. Furthermore, the display of such a text message may be omitted, and the autonomous driving BGM that starts together with the start of autonomous driving control may also serve as the autonomous driving start notification.

The notification request unit 72 ends the output of the autonomous driving BGM after continuing it for a predetermined time (several seconds to about 10 seconds). The notification request unit 72 may continue output of the autonomous driving BGM during the period in which autonomous driving control continues. As an example, if the host vehicle Am is a personally owned vehicle (Personally Owned Vehicle, hereinafter referred to as POV), the autonomous driving BGM ends after a predetermined time. On the other hand, if the host vehicle Am is a service vehicle that provides a mobility service, the autonomous driving BGM continues to be played continuously.

The notification request unit 72 notifies the passenger of the change in the behavior of the vehicle Am due to the autonomous driving control using the automatic driving BGM (see FIG. 8). The notification request unit 72 notifies the passenger of the timing of the acceleration exceeding a predetermined acceleration and the timing of the lane change or right/left turn by the automatic driving BGM. When the automatic driving BGM is stopped, the notification request unit 72 starts (resumes) the output of the automatic driving BGM at the timing when the behavior of the vehicle Am changes. In addition, when the automatic driving BGM is continuously played, the notification request unit 72 increases the volume of the automatic driving BGM at the timing when the behavior of the vehicle Am changes. The playback or increase in volume of the automatic driving BGM is started before the behavior change occurs and continues until the behavior of the vehicle Am stabilizes. As a result, the noise of the powertrain and tire noise associated with the increase in rotation speed are masked by the automatic driving BGM and are less noticeable to the passenger.

In a scene where an emergency vehicle approaches the host vehicle Am while autonomous driving control is being performed, the notification request unit 72 adjusts the directionality of the autonomous driving background music in cooperation with the sound field control unit 87 to show the relative direction of the emergency vehicle to the occupants of the host vehicle Am (see Figure 8). As described above, the target recognition unit 74 recognizes the approach of an emergency vehicle to the host vehicle Am. The target recognition unit 74 can use the exterior acoustic sensor 31 to detect the emergency vehicle. The exterior acoustic sensor 31 is configured to mainly include a microphone element such as a MEMS microphone or a condenser microphone. The notification request unit 72 outputs a command to the sound field control unit 87 specifying a virtual sound source position so as to indicate the relative position of the emergency vehicle recognized by the target recognition unit 74. As an example, the notification request unit 72 starts playing autonomous driving BGM in a manner that does not clarify the sound source position, and then lastly outputs sound from the speaker in the direction from which the emergency vehicle is approaching, and makes a virtual sound source appear in the direction of the emergency vehicle to the passenger. The passenger can grasp the relative position of the emergency vehicle from the direction from which the autonomous driving BGM is playing.

The notification request unit 72 suppresses the output of the automatic driving BGM and the driving assistance BGM when a change in the driving control state of the vehicle Am is scheduled. When a change in the driving control state that will end the autonomous driving control is scheduled, the notification request unit 72 outputs the driving change BGM and notifies the passengers of the change in the driving control state.

As an example, when the end of autonomous driving control corresponding to autonomous driving level 3 is scheduled, the notification request unit 72 executes a driver change request to the driver in the vehicle cabin (see FIG. 9). When a transition from autonomous driving control to driving assistance control is made, the notification request unit 72 restricts the output of the driver change BGM until a predefined time (several seconds to about 10 seconds, hereinafter, BGM limit time) has elapsed after the driver ends the second task in response to the driver change request. During the BGM limit time, the notification request unit 72 may suspend the output of the driver change BGM and put the playback of the driver change BGM for the vehicle cabin in a standby state, or may start the playback of the driver change BGM at a very low volume. At the BGM limit time, the driver resumes recognizing the environment outside the vehicle and grips the steering wheel. The notification request unit 72 may continue the output restriction until the driver resumes gripping the steering wheel by the vehicle interior monitoring unit 73.

The notification request unit 72 starts outputting the driver change BGM after the BGM time limit has elapsed. If the driver change BGM is being played at a low volume during the BGM time limit, the notification request unit 72 changes the playback volume of the driver change BGM to normal volume after the BGM time limit has elapsed. After autonomous driving control ends, the notification request unit 72 starts outputting driving assistance BGM in place of the driver change BGM. Note that if background sound linked to the changed driving control state is used as the driver change BGM, the notification request unit 72 continues outputting the driving assistance BGM during the switching period when switching from autonomous driving control to driving assistance control is performed.

The notification request unit 72 changes the output time of the driver change BGM depending on the changed autonomous driving level. When the driving control state transitions to driving assistance control corresponding to autonomous driving level 2 (see FIG. 9), after the transition to driving assistance control, the notification request unit 72 continues to output the driver change BGM for a predetermined time (several seconds to about 10 seconds). On the other hand, when the driving control state transitions to driving assistance control or manual driving corresponding to autonomous driving level 1, after the autonomous driving control is turned off, the notification request unit 72 does not output the driver change BGM, or outputs the driver change BGM for a shorter time than when transitioning to autonomous driving level 2. When the driver change BGM repeats a predetermined melody, the notification request unit 72 may sound the driver change BGM only once after the autonomous driving control is turned off.

<In-vehicle control for noise reduction>
The silent control unit 78 cooperates with the information linking unit 61 and the HMI control device 100 to implement volume adjustment control, sound field control, and the like for noise reduction in the silent mode.

The quietness control unit 78 changes the level of quietness in the vehicle cabin during the autonomous driving period according to the content of the second task ascertained by the in-vehicle monitoring unit 73. The in-vehicle monitoring unit 73 ascertains the content of the second task being performed by the driver based on in-vehicle monitor information obtained from the in-vehicle monitor device 29. The in-vehicle monitoring unit 73 determines the task state of the driver, for example, during a web conference (call), while watching content such as a movie, while operating a device, while eating, etc.

The silence control unit 78 increases or decreases the volume of the sound reproduced in the vehicle cabin depending on the content of the second task. As an example, when the driver is in a web conference, the silence control unit 78 lowers the volume of notification sounds and background sounds that are not related to the web conference, making the vehicle cabin quiet. Also, when the driver is watching content, the silence control unit 78 adjusts the volume of sounds related to the content so that they are louder than the volume set for notification sounds and background sounds.

The silent control unit 78 cooperates with the notification request unit 72 and the sound field control unit 87 to implement sound field control as in-vehicle control to make noise less audible. The in-vehicle monitoring unit 73 grasps the positional relationship between the noise source and the occupants of the vehicle Am. The silent control unit 78 adjusts the directionality of the in-vehicle sound output by the audio device 24 in the vehicle cabin based on the positional relationship grasped by the in-vehicle monitoring unit 73. The silent control unit 78 changes the virtual sound source position of the automatic driving background music and content audio, etc. by sound field control by the sound field control unit 87, and sets the virtual sound source at a position in the direction of the noise source with respect to the occupants. As a result, the position (direction) of the indoor sound becomes the same as the position (direction) of the noise source as seen by the occupants. As a result, the noise generated by the internal combustion engine and the motor generator is masked by the indoor sound and becomes less noticeable to the occupants.

<Normal notification due to normal noise generation>
During the automatic driving period, when the power generation control is performed by the control execution unit 64 and the driving control ECU 40 and this power generation control is normal, the notification request unit 72 performs a normal notification after the completion of the power generation control. The power generation control is a control that increases the noise of the power generation device 41 mounted on the host vehicle Am. Specifically, the power generation control is an acceleration control in which the rotation speed of the internal combustion engine or the motor generator included in the power generation device 41 exceeds the noise threshold. The power generation control is performed, for example, in a merging section and an uphill section.

The normal notification is a notification that indicates that the power generation control was normal. The normal notification is made after the power generation control that was caused by the noise has been completed, in other words, when the noise emitted by the power generation device 41 has become quieter. The normal notification is started, for example, after the merging is completed or after the uphill section has ended. The normal notification is made using displays on the meter display 21 and CID 22, as well as voice messages, etc. For example, a message such as "Control has been performed that increases noise" is presented to both the driver and passengers as a normal notification.

The notification request unit 72 does not issue a normal notification every time, but omits the normal notification as appropriate depending on the state of the occupant. The notification request unit 72 issues a normal notification only when the in-vehicle monitoring unit 73 detects that the occupant is anxious about the power generation control. The in-vehicle monitoring unit 73 uses various measurement information to determine whether the occupant of the vehicle Am is in an anxious state, in which the occupant feels anxious. The in-vehicle monitoring unit 73 determines whether the occupant is in an anxious state, for example, based on the content of the occupant's speech or the degree of trembling of the voice collected by the in-vehicle acoustic sensor 27. The in-vehicle monitoring unit 73 acquires the occupant's heart rate from a vital sensor installed in the driver's seat and passenger seat, or a wearable terminal worn by the occupant. The in-vehicle monitoring unit 73 determines whether the occupant is in an anxious state based on an increase in the occupant's heart rate. The notification request unit 72 issues a normal notification when the occupant is in an anxious state about the power generation control. On the other hand, if the passenger does not become anxious about the power generation control, the notification request unit 72 suppresses (cancels) the normal notification.

[Processing related to in-vehicle acoustic control]
In order to realize the in-vehicle sounds described above, the autonomous driving ECU 50b performs autonomous driving notification processing, behavior change notification processing, emergency vehicle notification processing, driving change notification processing, quietness control processing, and normal noise notification processing. Details of each processing performed mainly by the autonomous driving ECU 50b will be further described below based on Figures 10 to 15 and with reference to Figures 7 to 9.

<Autonomous driving notification processing>
10 is a process for notifying a passenger of the start of autonomous driving control of autonomous driving level 3 or higher. The autonomous driving notification process is continuously performed by the autonomous driving ECU 50b when the autonomous driving control is in a standby state.

In S211 of the autonomous driving notification process, the control switching unit 76 grasps the control schedule for switching the autonomous driving level. Based on the grasped control schedule, the control switching unit 76 determines in S212 whether or not switching to autonomous driving level 3 or higher is planned. If manual driving or driving assistance control is to continue (S212: NO), the transition to autonomous driving control is awaited by repeating S211 and S212.

On the other hand, if a switch to autonomous driving control is scheduled (S212: YES), the notification request unit 72 issues an autonomous driving start notification (see FIG. 8) in conjunction with the switch to autonomous driving control in S213. Furthermore, in S214, which is after the autonomous driving control starts, the notification request unit 72 starts outputting autonomous driving BGM (see FIG. 8) indicating that autonomous driving control is being performed. The notification request unit 72 refers to the autonomous driving level grasped by the control switching unit 76, and changes the mode of the autonomous driving BGM output in S214 depending on the current autonomous driving level.

<Behavior change notification process>
The behavior change notification process shown in Fig. 11 is a process for notifying a passenger of an event that causes a behavior change in the host vehicle Am by using automatic driving BGM. The behavior change notification process is started when the automatic driving period starts, and is continuously performed until the end of the automatic driving period.

In S221 of the behavior change notification process, the behavior determination unit 63 grasps the schedule for vehicle control in the autonomous driving control. In S222, the behavior determination unit 63 determines whether a change in vehicle behavior is scheduled. If no change in vehicle behavior is scheduled (S222: NO), S221 and S222 are repeated to wait for the occurrence of a behavior change. In contrast, if a change in vehicle behavior is scheduled (S222: YES), the notification request unit 72 outputs autonomous driving BGM to notify of the behavior change in S223 (see FIG. 8). According to S223, output of autonomous driving BGM is started at the timing when a change in the behavior of the host vehicle Am occurs due to autonomous driving control. In S223, notification control to increase the volume of the autonomous driving BGM may be implemented.

<Emergency vehicle notification processing>
The emergency vehicle notification process shown in Fig. 12 is a process for notifying passengers of the approach of an emergency vehicle by using automatic driving BGM. The emergency vehicle notification process, like the behavior change notification process (see Fig. 11), is started when the automatic driving period starts and is continuously performed until the automatic driving period ends.

In S231 of the emergency vehicle notification process, the target recognition unit 74 recognizes the approach of an emergency vehicle to the vehicle Am. If no emergency vehicle is approaching (S231: NO), S231 is repeated to wait for the approach of the emergency vehicle. On the other hand, if the approach of an emergency vehicle is recognized (S231: YES), the target recognition unit 74 recognizes the relative direction of the emergency vehicle in S232. Next, in S233, the interior monitoring unit 73 recognizes the positions of the occupants in the vehicle cabin. The order of execution of S232 and S233 may be changed.

In S234, the notification request unit 72 cooperates with the sound field control unit 87 to control the sound field of the autonomous driving BGM. If the output of the autonomous driving BGM is interrupted, the notification request unit 72 resumes the output of the autonomous driving BGM in S234. The notification request unit 72 adjusts the directionality of the autonomous driving BGM being played based on the positional relationship between the emergency vehicle and the passenger grasped in S232 and S233. The notification request unit 72 shows the passenger the relative direction of the emergency vehicle by setting a virtual sound source position in the direction in which the emergency vehicle is approaching the passenger (see FIG. 8). When the emergency vehicle approaches within a predetermined distance, the notification request unit 72 ends the autonomous driving BGM so as not to prevent the passenger from grasping the siren sound of the emergency vehicle.

<Operator change notification process>
13 is a process for notifying the passenger of the end of the autonomous driving control. The driving change notification process is continuously performed by the automatic driving ECU 50b when the autonomous driving control is in an execution state.

In S241 of the driving change notification process, the control switching unit 76 grasps the control schedule for switching the autonomous driving level. Based on the grasped control schedule, the control switching unit 76 determines in S242 whether autonomous driving control of autonomous driving level 3 or higher is planned to be continued. If autonomous driving control is planned to be continued (S242: YES), S241 and S242 are repeated to wait for the autonomous driving control to end. On the other hand, if autonomous driving control is planned to end (S242: NO), the notification request unit 72 makes a driving change request to the driver in S243 (see FIG. 9). If autonomous driving BGM is being played, the output of the autonomous driving BGM is suppressed in S243.

In S244, the in-vehicle monitoring unit 73 grasps the driver's state. In S245, the in-vehicle monitoring unit 73 judges whether the driver has finished the second task. If the second task is continuing (S245: NO), S244 and S245 are repeated to wait for the second task to end. On the other hand, if the end of the second task is grasped (S245: YES), the notification request unit 72 judges in S246 whether a predetermined BGM time limit has elapsed since the end of the second task. Based on the judgment in S246, the notification request unit 72 limits the output of the driving change BGM until the BGM time limit has elapsed.

When the BGM time limit has elapsed (S246: YES), the control switching unit 76 determines the new autonomous driving level in S247 based on the control schedule obtained in S241. If a transition to autonomous driving level 2 is scheduled (S247: YES), the notification request unit 72 outputs the driver change BGM normally in S248 (see FIG. 9). In this case, the output of the driver change BGM continues until a predetermined time has elapsed after the driver change. On the other hand, if a transition to autonomous driving level 1 or manual driving is scheduled (S247: NO), the notification request unit 72 outputs the driver change BGM in a more restricted manner than usual in S249. In this case, the notification request unit 72 may stop outputting the driver change BGM, or may end the playback of the driver change BGM in a shorter time than usual.

<Quietness control processing>
14 is a process for adjusting the volume and sound field of the interior sound reproduced in the vehicle cabin during the autonomous driving period. The emergency vehicle notification process is started when the autonomous driving period starts, and is repeatedly performed until the autonomous driving period ends.

In S261 of the driver change notification process, the silence control unit 78 determines the mode of the vehicle interior control set in the mode switching process (see FIG. 3). In S262, the silence control unit 78 determines whether the control mode is set to the silence mode (see FIG. 3, S20). If the control mode is set to the normal mode (see FIG. 3, S19) (S262: NO), the silence control process is temporarily terminated.

In contrast, if the control mode is set to silent mode, the notification request unit 72 performs volume adjustment control according to the content of the second task in S263. Furthermore, in S264, the interior monitoring unit 73 grasps the positional relationship between the noise source and the occupant. The notification request unit 72 then performs sound field control using the sound field control unit 87 to adjust the directionality of the interior sound, and sets a virtual sound source of the interior sound at a position in the direction of the noise source relative to the occupant. The order of performing the above S263 and S264 may be changed as appropriate.

<Normal noise notification processing>
15 is a process for making a normal noise notification after an increase in noise occurs in the power generation device 41. The normal noise notification process is started when the automatic operation period starts, and is repeatedly performed until the automatic operation period ends.

In S271 of the normal noise notification process, the behavior determination unit 63 determines whether or not the noise of the power generation device 41 has increased due to the implementation of power generation control. If power generation control accompanied by an increase in noise is not implemented (S271: NO), the behavior determination unit 63 waits for the implementation of power generation control accompanied by an increase in noise. Then, if power generation control is implemented (S271: YES), the behavior determination unit 63 determines in S272 whether or not the power generation control has ended. If power generation control is continuing (S272: NO), the behavior determination unit 63 waits for the end of power generation control.

When the behavior determination unit 63 determines that the power generation control has ended (S272: YES), the in-vehicle monitoring unit 73 determines in S273 whether the passenger's state of anxiety was detected during the period in which the power generation control was being performed. If the passenger's state of anxiety was not detected (S273: NO), the normal noise notification process is temporarily terminated. On the other hand, if the passenger's state of anxiety was detected (S273: YES), the notification request unit 72 performs a normal notification in S274. As described above, a normal notification is only performed when the passenger's state of anxiety is detected.

(Summary of the second embodiment)
In the second embodiment described above, the noise reduction control is performed during the autonomous driving period, and the interior of the vehicle Am can be made quieter. As a result, the same effect as in the first embodiment is achieved, and it is possible to suppress the anxiety that passengers who are not involved in driving feel about the autonomous driving control.

In addition, in the second embodiment, if power generation control that increases the noise of the power generation device 41 mounted on the vehicle Am is performed during an automatic driving period, after the power generation control is completed, a normal notification is issued to indicate that the power generation control was normal. Therefore, even if the noise of the power generation device 41 inevitably increases due to merging, climbing, etc., the anxiety felt by the passengers can be quickly alleviated.

In addition, in the second embodiment, it is determined whether or not the occupant of the vehicle Am is in an anxious state that makes him feel uneasy. Then, if the occupant is not in an anxious state in response to the power generation control, the normal notification is suppressed. As a result of the above, it is possible to avoid a situation in which the occupant feels annoyed by repeated normal notifications.

Furthermore, in the second embodiment, after the autonomous driving control starts, autonomous driving background music is output, indicating that the autonomous driving control is being performed. As a result, the occupants can recognize that the autonomous driving control has started normally due to the autonomous driving background music played inside the vehicle cabin. As a result, anxiety about the autonomous driving control can be suppressed. Note that the autonomous driving background music corresponds to "autonomous driving background sound."

In addition, in the second embodiment, when a change in the driving control state is scheduled, the output of the automatic driving background music is suppressed. As a result, the passenger can understand the scheduled change in the driving control state from the change in the automatic driving background music with ample time to spare. Therefore, the passenger's anxiety caused by the change in the driving control state can be suppressed.

In the second embodiment, when a change in the driving control state is scheduled, driver change BGM that notifies the driver of the change in driving control state is output. By outputting such driver change BGM, the passenger can more clearly understand the scheduled change in the driving control state. As a result, the passenger's anxiety caused by the change in the driving control state can be suppressed. The driver change BGM corresponds to the "change notification background sound."

Furthermore, in the second embodiment, the autonomous driving level linked to the planned changed driving control state is grasped. Then, the output time of the driver-switching BGM is changed according to the changed autonomous driving level. As a result, the passenger can recognize the changed autonomous driving level from the output time of the driver-switching BGM. As a result, the passenger's anxiety after the change in driving control state can be reduced.

In addition, in the second embodiment, it is determined whether the driver in the vehicle cabin is performing a second task that has been permitted in advance during the autonomous driving period. Then, when a transition is made from autonomous driving control to driving assistance control, the output of the driving changeover BGM is restricted until a predetermined time has elapsed after the second task ends. As a result, the driving changeover BGM is unlikely to interfere with the driver's recognition of the outside vehicle environment that begins after the second task ends. As a result, the driving changeover BGM can reliably support a smooth handover of driving to the driver.

In addition, in the second embodiment, a process of starting output of the autonomous driving BGM or a process of increasing the volume of the autonomous driving BGM being output is performed at the timing when a change occurs in the behavior of the vehicle Am. Therefore, noise caused by the behavior change is less noticeable to the passengers due to the autonomous driving BGM. As a result, the passengers' anxiety in scenes where noise occurs can be suppressed.

Furthermore, in the second embodiment, the approach of an emergency vehicle to the vehicle Am is detected. Then, by adjusting the directionality of the autonomous driving background music, the relative direction of the emergency vehicle is shown to the occupants of the vehicle Am. This type of sound field control makes it possible to promptly indicate to the occupants the location of the emergency vehicle. As a result, a situation in which the occupants feel uneasy due to the sudden approach of an emergency vehicle can be avoided.

In addition, in the second embodiment, the autonomous driving level linked to the driving control state currently being executed is grasped. Then, the mode of the autonomous driving BGM is changed according to the autonomous driving level. As a result, the passenger can grasp the current driving control state from the mode of the autonomous driving BGM. In this way, it becomes easier for the passenger to grasp the driving control state, which can reduce the passenger's anxiety about the autonomous driving control.

In the second embodiment, the positional relationship between the noise source and the occupants of the vehicle Am is grasped. Then, the directivity of the interior sound output by the audio device 24 in the vehicle cabin is adjusted, and a virtual sound source of the interior sound is set at a position in the direction of the source relative to the occupants. This type of noise reduction control makes it difficult for the occupants to recognize the noise due to the interior sound. As a result, the occupants' anxiety caused by the noise can be suppressed.

Other Embodiments
Although several 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 not departing from the gist of the present disclosure.

The host vehicle Am equipped with the autonomous driving ECU 50b according to the first modification of the above embodiment is operated as a driverless vehicle that provides mobility services without a specific driver on board. The operation of the driverless vehicle is remotely monitored by a remote management center located remotely from the host vehicle. Even in the first modification, the autonomous driving ECU 50b functions as a vehicle control device and performs noise reduction control.

In addition, in variant 1, the interior monitoring unit 73 uses interior noise information detected by the interior acoustic sensor 27 to determine whether the interior of the vehicle is quiet or not. If the noise accompanying the running of the vehicle Am is greater than a predetermined judgment criterion and the interior of the vehicle is not quiet, the notification request unit 72 issues a notification regarding the quietness (hereinafter, a noise notification) to the remote management center. Based on the noise notification, the manager at the remote management center can check whether any abnormalities have occurred in the driverless vehicle.

In Variation 2 of the above embodiment, an exterior acoustic sensor that detects sounds outside the vehicle is provided on the vehicle Am. The exterior acoustic sensor has substantially the same configuration as the interior acoustic sensor 27, converts sounds outside the vehicle into an electrical signal, and provides the output signal to the autonomous driving ECU 50b. The autonomous driving ECU 50b acquires the output signal of the exterior acoustic sensor as one piece of detection information. In Variation 2, the target recognition unit 74 can recognize the approach of an emergency vehicle by detecting the siren of the emergency vehicle using the output signal of the exterior acoustic sensor.

In the third variation of the above embodiment, only one of the power control and the in-vehicle control for noise reduction is implemented. In the fourth variation of the above embodiment, only one of the power selection control and the power suppression control is implemented as the power control. Furthermore, in the fifth variation of the above embodiment, at least one of the in-vehicle controls, namely, the volume adjustment control, the noise canceling control, the noise masking control, the opening/closing control, and the sound field control, is omitted. As in the fifth variation, the content of the in-vehicle control for noise reduction may be changed as appropriate. In addition, the content of the in-vehicle control to be implemented may be preset based on the operation by the user, such as the driver.

In variant 6 of the above embodiment, the process of requesting the driver to approve the implementation of noise reduction control is omitted. In variant 6, the noise reduction control unit 78 decides to implement noise reduction control based on switching to autonomous driving level 3. Furthermore, the process of determining the type of passenger may be omitted.

The music (melody) used for the automatic driving BGM, driving assistance BGM, and driving change BGM used in the second embodiment above may be changed as appropriate. For example, at least two of the automatic driving BGM, driving assistance BGM, and driving change BGM may be the same. Furthermore, these background sounds may be changeable based on the user operation of the vehicle Am.

At least some of the functions of the vehicle control device according to the present disclosure may be implemented in an on-board ECU different from the autonomous driving ECU 50b. In variant 7 of the above embodiment, at least some of the functions of the vehicle control device are implemented in the cruise control ECU 40, which performs mode switching processing and power control processing. In variant 7, the cruise control ECU 40, or a system including the cruise control ECU 40 and the autonomous driving ECU 50b, corresponds to the "vehicle control device."

In variant 8 of the above embodiment, at least some of the functions of the vehicle control device are implemented in the HMI control device 100, which performs mode switching processing and in-vehicle control processing. In variant 8, the HMI control device 100, or a system including the HMI control device 100 and the autonomous driving ECU 50b, corresponds to the "vehicle control device."

The configuration of the system that realizes the autonomous driving function may be modified as appropriate. As an example, in variant 9 of the above embodiment, the functions of the driving assistance ECU 50a and the autonomous driving ECU 50b are provided by a single autonomous driving ECU. That is, the autonomous driving ECU 50b of variant 9 is equipped with the functions of the driving assistance ECU 50a. In variant 10 of the above embodiment, the functions of the driving assistance ECU 50a, the autonomous driving ECU 50b, and the HMI control device 100 are provided by a single integrated ECU. In variant 10, the integrated ECU corresponds to the "vehicle control device."

In the above embodiment, each function provided by the autonomous driving ECU can be provided by software and hardware that executes it, by software alone, by hardware alone, or by 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 a large number of logic circuits, or by analog circuits. Furthermore, the software for realizing such functions may include at least a portion of code that is automatically generated by, for example, a neural network or language model trained using camera footage of the real world.

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 CPU (Central Processing Unit) and a GPU (Graphics Processing Unit). The processing unit may further include an FPGA (Field-Programmable Gate Array), an NPU (Neural network Processing Unit), and IP cores with other dedicated functions. Such processing units may be individually implemented on a printed circuit board, or may be implemented in an ASIC (Application Specific Integrated Circuit) and an FPGA, etc.

The form of the storage medium (non-transitory tangible storage medium) that stores various programs and the like in the above embodiments may be changed as appropriate. Furthermore, the storage medium is not limited to a configuration in which it is provided on a circuit board, and may be provided in the form of a memory card or the like, inserted into a slot portion, 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, etc., from which a program is copied or distributed to the autonomous driving ECU, etc.

Vehicles equipped with the above-mentioned autonomous driving system and HMI system are not limited to general private passenger cars, but may be rental cars, manned taxi cars, ride-sharing cars, freight cars, buses, etc. Furthermore, vehicles equipped with the autonomous driving system and HMI system may be right-hand drive vehicles or left-hand drive vehicles. Furthermore, the traffic environment in which the vehicle travels may be a traffic environment based on left-hand traffic or a traffic environment based on right-hand traffic. Vehicle 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 position of the vehicle's steering wheel, etc.

The control unit and the method described in the present disclosure may be realized by a dedicated computer comprising a processor programmed to execute one or more functions embodied in a computer program. Alternatively, the device and the method described in the present disclosure may be realized by a dedicated hardware logic circuit. Alternatively, the device and the method described in the present disclosure may be realized by one or more dedicated computers configured by a combination of a processor that executes a computer program and one or more hardware logic circuits. Furthermore, the computer program may be stored on a computer-readable non-transient tangible recording medium as instructions executed by the computer.

(Disclosure of technical ideas)
This specification discloses multiple technical ideas described in the following multiple dependent claims. Some of the claims may be described in a multiple dependent form, in which the subsequent claim alternatively refers to the preceding claim. Furthermore, some of the claims may be described in a multiple dependent form, in which the subsequent claim alternatively refers to the preceding claim. The claims described in these multiple dependent forms define multiple technical ideas.

(Technical Concept 1)
A vehicle control device used in a vehicle (Am) capable of traveling by autonomous driving control in which a driver is not required to monitor the surroundings,
A control grasping unit (76) that grasps that the driving control state of the host vehicle has been switched to a state in which the host vehicle is driven by the autonomous driving control;
A noise reduction control unit (78) that performs noise reduction control for reducing noise in a vehicle cabin of the vehicle during an automatic driving period in which the vehicle is driven by the autonomous driving control, more than during a monitoring period in which the driver has an obligation to monitor the surroundings;
A vehicle control device comprising:
(Technical Concept 2)
The vehicle control device according to Technical Idea 1, wherein the noise reduction control unit implements a power suppression control for suppressing a rotation speed of a power generating device (41) mounted on the host vehicle as the noise reduction control.
(Technical Concept 3)
a playback status determining unit (71) for determining a state of content playback by the audio device (24) in the vehicle interior,
The vehicle control device according to Technical Concept 2, wherein the silent control unit relaxes the power suppression control when the content is being played back in the vehicle compartment.
(Technical Concept 4)
A vehicle exterior grasping unit (74) for grasping an approach of an emergency vehicle to the vehicle,
The vehicle control device according to Technical Idea 2 or 3, wherein the silent control unit stops the power suppression control when the approach of the emergency vehicle is detected.
(Technical Concept 5)
An evacuation control unit (77) that performs emergency evacuation control based on the occurrence of an abnormality related to the vehicle,
A vehicle control device described in any one of technical ideas 2 to 4, in which the silent control unit determines whether the power suppression control interferes with the emergency evacuation control, and if it determines that the power suppression control does not interfere with the emergency evacuation control, performs the power suppression control during an evacuation driving period in which the vehicle travels by the emergency evacuation control.
(Technical Concept 6)
A vehicle control device as described in any one of technical ideas 2 to 5, further comprising an alarm implementation unit (72) that issues an alarm indicating that the set vehicle speed will not be reached if the driving speed of the vehicle will not reach the set vehicle speed set by the driver when the power suppression control is implemented.
(Technical Concept 7)
A vehicle control device according to any one of technical ideas 2 to 6, wherein the silent control unit relaxes the power suppression control until the set vehicle speed is reached if the driving speed of the vehicle would not reach the set vehicle speed set by the driver if the power suppression control is implemented.
(Technical Concept 8)
A vehicle control device as described in any one of technical ideas 1 to 7, further comprising an alarm implementation unit (72) that, when power generation control that increases the noise of a power generation device (41) mounted on the vehicle is performed during the automatic driving period, issues a normal alarm indicating that the power generation control was normal control after the power generation control is completed.
(Technical Concept 9)
A vehicle interior grasping unit (73) for grasping whether or not a passenger of the vehicle is in an anxious state,
The vehicle control device according to technical idea 8, wherein the notification implementation unit suppresses the normal notification if the occupant does not enter the anxious state in response to the power generation control.
(Technical Concept 10)
A vehicle control device according to any one of technical ideas 1 to 9, further comprising an alert implementation unit (72) that outputs an autonomous driving background sound indicating that the autonomous driving control is being performed after the autonomous driving control is started.
(Technical Concept 11)
The vehicle control device according to technical idea 10, wherein the notification implementation unit suppresses output of the autonomous driving background sound when a change in the driving control state is scheduled.
(Technical Concept 12)
The vehicle control device according to Technical Idea 10 or 11, wherein the notification execution unit outputs a change notification background sound that notifies the driver of the change in the driving control state when a change in the driving control state is scheduled.
(Technical Concept 13)
The control grasping unit grasps an autonomous driving level associated with the driving control state after the planned change,
The vehicle control device according to technical idea 12, wherein the notification implementation unit changes the output time of the change notification background sound according to the changed autonomous driving level.
(Technical Concept 14)
a vehicle interior grasping unit (73) configured to grasp whether the driver is performing a specific action other than driving that is permitted in advance during the automatic driving period,
The vehicle control device according to technical idea 12 or 13, wherein the notification implementation unit limits the output of the change notification background sound until a predetermined time has elapsed after the driver's specific action is completed, when a transition is made from the autonomous driving control to the driving control state in which the driver is obligated to monitor the surroundings.
(Technical Concept 15)
The vehicle control device described in any one of technical ideas 10 to 14, wherein the notification implementation unit starts outputting the autonomous driving background sound at a timing when a change occurs in the behavior of the vehicle due to the autonomous driving control, or increases the volume of the autonomous driving background sound that is being output.
(Technical Concept 16)
A vehicle exterior grasping unit (74) for grasping an approach of an emergency vehicle to the vehicle,
The vehicle control device described in any one of technical ideas 10 to 15, wherein the notification implementation unit adjusts the directivity of the autonomous driving background sound and indicates the relative direction of the emergency vehicle to the occupants of the vehicle.
(Technical Concept 17)
The control grasping unit grasps an autonomous driving level associated with the driving control state being executed,
The vehicle control device according to any one of technical ideas 10 to 16, wherein the notification implementation unit changes the manner of the autonomous driving background sound depending on the autonomous driving level.
(Technical Concept 18)
A vehicle interior recognition unit (73) that recognizes a positional relationship between a noise source and an occupant of the vehicle,
The vehicle control device according to any one of technical ideas 1 to 17, wherein the noise reduction control unit implements sound field control that adjusts the directivity of the in-vehicle sound output by an audio device (24) in the vehicle cabin and sets a virtual sound source of the in-vehicle sound at a position in the direction of the source relative to the occupants, as the noise reduction control.
(Technical Concept 19)
The vehicle control device according to any one of technical ideas 1 to 18, wherein the noise reduction control unit implements volume adjustment control for increasing the volume of content playback by an audio device (24) in the vehicle cabin as the noise reduction control.
(Technical Concept 20)
The vehicle control device according to any one of technical ideas 1 to 19, wherein the noise reduction control unit implements noise canceling control as the noise reduction control, using a noise reduction device (81) that suppresses noise inside the vehicle cabin to reduce noise in a passenger seat where passengers other than the driver are seated to a greater extent than noise in the driver's seat where the driver is seated.
(Technical Concept 21)
A vehicle interior recognition unit (73) for determining whether a specific type of passenger for whom noise reduction is useful is present in the vehicle interior,
The vehicle control device according to any one of Technical Ideas 1 to 20, wherein the noise reduction control unit performs the noise reduction control when the specific type of occupant is present in the vehicle cabin.
(Technical Concept 22)
The vehicle control device according to any one of technical ideas 1 to 21, wherein the noise reduction control unit uses a sound dummy device (82) that outputs a sound dummy that makes noise in the vehicle cabin less audible to the occupants for the noise reduction control.
(Technical Concept 23)
The vehicle control device according to any one of technical ideas 1 to 22, wherein the noise reduction control unit implements an opening/closing control that adjusts the open/closed state of a window provided in the vehicle in order to reduce noise inside the vehicle cabin.
(Technical Concept 24)
A vehicle control device as described in any one of technical ideas 1 to 23, further comprising an alert implementation unit (72) that issues an alert regarding quietness to a remote management center located remotely from the vehicle when noise accompanying the driving of the vehicle is greater than a predetermined judgment criterion.
(Technical Concept 25)
a notification execution unit (72) that executes a notification to inquire of the driver whether or not to execute the noise reduction control based on the switching to the autonomous driving control,
The vehicle control device according to any one of Technical Ideas 1 to 24, wherein the noise reduction control unit performs the noise reduction control when the implementation of the noise reduction control is approved by the driver.
(Technical Concept 26)
The vehicle control device according to any one of technical ideas 1 to 25, wherein when a power generating device (41) mounted on the vehicle includes multiple power sources, the noise reduction control unit implements a power selection control that preferentially operates a quiet power source that generates less noise among the multiple power sources as the noise reduction control.
(Technical Concept 27)
A vehicle control device described in any one of technical ideas 1 to 26, in which the noise reduction control unit stops implementing the noise reduction control during the automatic driving period when the drive mode of the vehicle is set to a sports mode that prioritizes driving performance.
(Technical Concept 28)
A vehicle control program used in a vehicle (Am) capable of traveling by autonomous driving control without a driver having to monitor the surroundings,
It is determined that the driving control state of the host vehicle has been switched to a state in which the host vehicle is driven by the autonomous driving control (S13).
During an automatic driving period during which the vehicle is driven by the autonomous driving control, a noise reduction control is performed to reduce noise in the vehicle cabin compared to a monitoring period during which the driver has an obligation to monitor the surroundings (S20).
A vehicle control program that causes at least one processing unit (51) to execute a process including the steps of:

Claims (28)

A vehicle control device used in a vehicle (Am) capable of traveling by autonomous driving control in which a driver is not required to monitor the surroundings,
A control grasping unit (76) that grasps that the driving control state of the host vehicle has been switched to a state in which the host vehicle is driven by the autonomous driving control;
a noise reduction control unit (78) that performs noise reduction control for reducing noise in a vehicle cabin of the vehicle during an automatic driving period in which the vehicle is driven by the autonomous driving control, more than during a monitoring period in which the driver has an obligation to monitor the surroundings;
A vehicle control device comprising: The vehicle control device according to claim 1, wherein the silencing control unit implements power suppression control, which suppresses the rotation speed of a power generating device (41) mounted on the vehicle, as the silencing control. a playback status determining unit (71) for determining a state of content playback by the audio device (24) in the vehicle interior,
The vehicle control device according to claim 2 , wherein the silent control unit relaxes the power suppression control when the content is being reproduced in the vehicle compartment. A vehicle exterior grasping unit (74) for grasping an approach of an emergency vehicle to the vehicle,
The vehicle control device according to claim 2 , wherein the silent control unit halts the power suppression control when the approach of the emergency vehicle is detected. An evacuation control unit (77) that performs emergency evacuation control based on the occurrence of an abnormality related to the vehicle,
3. The vehicle control device according to claim 2, wherein the silent control unit determines whether the power suppression control interferes with the emergency evacuation control, and if it determines that the power suppression control does not interfere with the emergency evacuation control, performs the power suppression control during an evacuation running period in which the vehicle runs under the emergency evacuation control. The vehicle control device according to claim 2, further comprising a notification unit (72) that issues a notification indicating that the set vehicle speed will not be reached if the driving speed of the vehicle will not reach the set vehicle speed set by the driver if the power suppression control is implemented. The vehicle control device according to claim 2, wherein, if the driving speed of the vehicle does not reach the set vehicle speed set by the driver when the power suppression control is implemented, the silent control unit relaxes the power suppression control until the driving speed reaches the set vehicle speed. The vehicle control device according to claim 1, further comprising: a notification unit (72) that, when power generation control that increases the noise of the power generation device (41) mounted on the vehicle is performed during the automatic driving period, issues a normal notification after the power generation control is completed, indicating that the power generation control was normal. A vehicle interior grasping unit (73) for grasping whether or not a passenger of the vehicle is in an anxious state,
The vehicle control device according to claim 8 , wherein the notification execution unit suppresses the normal notification when the occupant does not enter the anxious state in response to the power generation control. The vehicle control device according to claim 1, further comprising a notification unit (72) that outputs an automatic driving background sound indicating that the autonomous driving control is being performed after the autonomous driving control is started. The vehicle control device according to claim 10, wherein the notification unit suppresses output of the autonomous driving background sound when a change in the driving control state is scheduled. The vehicle control device according to claim 10, wherein the notification unit outputs a change notification background sound that notifies the driver of a change in the driving control state when a change in the driving control state is scheduled. The control grasping unit grasps an autonomous driving level associated with the driving control state after the planned change,
The vehicle control device according to claim 12 , wherein the notification execution unit changes an output time of the change notification background sound in accordance with the changed autonomous driving level. a vehicle interior grasping unit (73) configured to grasp whether the driver is performing a specific action other than driving that is permitted in advance during the automatic driving period,
13. The vehicle control device according to claim 12, wherein the notification implementation unit, when a transition is made from the autonomous driving control to the driving control state in which the driver is obligated to monitor the surroundings, limits the output of the change notification background sound until a predetermined time has elapsed after the driver completes the specific action. The vehicle control device according to claim 10, wherein the notification unit starts outputting the autonomous driving background sound when the autonomous driving control causes a change in the behavior of the vehicle, or increases the volume of the autonomous driving background sound being output. A vehicle exterior grasping unit (74) for grasping an approach of an emergency vehicle to the vehicle,
The vehicle control device according to claim 10 , wherein the notification implementation unit adjusts directivity of the autonomous driving background sound to indicate the relative direction of the emergency vehicle to a passenger of the host vehicle. The control grasping unit grasps an autonomous driving level associated with the driving control state being executed,
The vehicle control device according to claim 10 , wherein the notification implementation unit changes a manner of the autonomous driving background sound depending on the autonomous driving level. A vehicle interior recognition unit (73) that recognizes a positional relationship between a noise source and an occupant of the vehicle,
2. The vehicle control device according to claim 1, wherein the noise reduction control is implemented by a sound field control that adjusts the directivity of the interior sound output by an audio device (24) in the vehicle cabin and sets a virtual sound source of the interior sound at a position in the direction of the source of the sound relative to the passengers. The vehicle control device according to claim 1, wherein the silencing control unit performs volume adjustment control to increase the volume of content played by the audio device (24) in the vehicle cabin as the silencing control. The vehicle control device according to claim 1, wherein the silencing control unit uses a noise suppression device (81) that suppresses noise in the vehicle cabin to implement noise reduction control that reduces the noise in the passenger seat where passengers other than the driver are seated to a greater extent than the noise in the driver's seat where the driver is seated, as the silencing control. A vehicle interior recognition unit (73) for determining whether a specific type of passenger for whom noise reduction is useful is present in the vehicle interior,
The vehicle control device according to claim 1 , wherein the noise reduction control unit performs the noise reduction control when the specific type of occupant is present in the vehicle compartment. The vehicle control device according to claim 1, wherein the silencing control unit uses a sound dummy device (82) for silencing control, the sound dummy device outputting a sound that makes noise in the vehicle cabin less audible to the passengers. The vehicle control device according to claim 1, wherein the noise reduction control unit performs an opening/closing control that adjusts the open/closed state of a window provided in the vehicle to reduce noise in the vehicle interior. The vehicle control device according to claim 1, further comprising a notification unit (72) that issues a notification regarding quietness to a remote management center located remotely from the vehicle when the noise accompanying the running of the vehicle is greater than a predetermined judgment criterion. a notification execution unit (72) that executes a notification to inquire of the driver whether or not to execute the noise reduction control based on the switching to the autonomous driving control,
The vehicle control device according to claim 1 , wherein the noise reduction control unit performs the noise reduction control when the driver approves the performance of the noise reduction control. The vehicle control device according to claim 1, wherein the noise reduction control unit performs power selection control as the noise reduction control, in which, when the power generating device (41) mounted on the vehicle includes multiple power sources, a quiet power source that generates less noise is preferentially operated among the multiple power sources. The vehicle control device according to claim 1, wherein the noise reduction control unit stops implementing the noise reduction control during the automatic driving period when the drive mode of the host vehicle is set to a sports mode that prioritizes driving performance. A vehicle control method used in a vehicle (Am) capable of traveling by autonomous driving control in which a driver is not required to monitor the surroundings,
It is determined that the driving control state of the host vehicle has been switched to a state in which the host vehicle is driven by the autonomous driving control (S13).
During an automatic driving period during which the vehicle is driven by the autonomous driving control, a noise reduction control is performed to reduce noise in the vehicle cabin compared to a monitoring period during which the driver is required to monitor the surroundings (S20).
The vehicle control method includes the steps of:

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