JP7739761B2 - Vehicle control device - Google Patents

Description

The present invention relates to a vehicle control device, and more particularly to a vehicle control device for driving assistance.

Vehicles have been proposed in the past that are configured to automatically activate driving assistance control when predetermined activation conditions are met (see, for example, Patent Document 1). In the vehicle described in Patent Document 1, driving assistance control is activated automatically in accordance with the driver's situation (image and voice of the driver), without the driver having to perform a switching operation. Typically, the driver is notified of this automatic intervention of driving assistance control.

JP 2017-188127 A

However, elderly people and those with mild cognitive impairment (MCI) often require driving assistance control due to declines in physical and perceptual functions. For this reason, frequent notifications of automatic intervention by driving assistance control could be irritating and confusing for drivers. On the other hand, for healthy drivers with normal driving ability, automatic intervention by driving assistance control does not occur frequently, so it is preferable to provide notifications that encourage the maintenance or improvement of driving ability.

The present invention was made to solve these problems, and aims to provide a vehicle control device that appropriately notifies the driver of automatic intervention of driving assistance control according to the driver's level of driving ability.

In order to achieve the above-mentioned object, the present invention provides a vehicle control device that estimates driving risks that may occur to a vehicle due to the vehicle's driving environment, performs driving assistance control on the vehicle to avoid the occurrence of the driving risks, and performs a notification process to notify the driver of the vehicle of the execution of the driving assistance control.The vehicle control device performs a driving ability evaluation process to estimate a driving ability value that represents the magnitude of the driver's driving ability, and when executing the driving assistance control, performs the notification process when the driving ability value is in a high ability state greater than a predetermined threshold, but does not perform the notification process when the driving ability value is in a low ability state less than the predetermined threshold.The driving ability value includes a perceptual ability value that represents the magnitude of the perceptual ability to recognize objects including traffic participants outside the vehicle, and a motor ability value that represents the magnitude of the motor ability to perform vehicle operation of the vehicle, and the perceptual ability value is calculated according to the probability that the driver's line of sight will capture a perceptual object outside the vehicle, and the motor ability value is calculated according to the acceleration caused to the vehicle by the driver's vehicle operation .

According to the present invention configured in this way, for drivers with low driving ability, the driving assistance control intervention is relatively frequent, so the notification process is disabled. This makes it possible to prevent the driver from feeling annoyed by the frequent notification process or from becoming confused by the notification process. On the other hand, for drivers with medium or relatively high driving ability, the present invention can encourage the driver to voluntarily maintain and improve their driving ability by notifying them of the intervention of driving assistance control.

Furthermore , in the present invention configured as described above , driving ability is divided into perceptual ability and motor ability, and notification processing can be performed appropriately depending on the combination of the magnitudes of these abilities.

Furthermore , in the present invention configured as described above , the perceptual ability value and motor ability value can be calculated and updated relatively easily.

Furthermore, in the present invention, preferably, the low ability state is when the perceptual ability value is equal to or less than the first perceptual threshold, or when the motor ability value is equal to or less than the first motor threshold, or when the perceptual ability value is equal to or less than a second perceptual threshold set to a value greater than the first perceptual threshold and the motor ability value is equal to or less than a second motor threshold set to a value greater than the first motor threshold, and the high ability state is when the perceptual ability value exceeds the first perceptual threshold and the motor ability value exceeds the second motor threshold, or when the perceptual ability value exceeds the second perceptual threshold and the motor ability value exceeds the first motor threshold. In this configuration of the present invention, by setting thresholds, it is possible to more appropriately execute notification processing according to the combination of the magnitudes of each ability.

Furthermore, in the present invention, preferably, in a low-capacity state, the vehicle control device does not execute notification processing, but executes driving assistance control to automatically drive the vehicle to a predetermined destination. With this configuration, the present invention can enable a driver with reduced driving ability to safely reach their destination through automated driving.

Furthermore, in the present invention, preferably, in the high ability state, the vehicle control device executes notification processing when the perceptual ability value exceeds the first perceptual threshold but is less than the second perceptual threshold and the motor ability value exceeds the second motor threshold, or when the motor ability value exceeds the first motor threshold but is less than a third motor threshold set to a value greater than the second motor threshold, and the perceptual ability value exceeds the second perceptual threshold. In this configuration, the present invention executes notification processing regarding the execution of vehicle assistance control for drivers with average driving ability, allowing the driver to use the intervention of vehicle assistance control as motivation to maintain or improve their driving ability.

Furthermore, in the present invention, preferably, in the high ability state, the vehicle control device executes a notification process when the perceptual ability value is equal to or greater than the second perceptual threshold and the motor ability value is equal to or greater than a third motor threshold set to a value greater than the second motor threshold, and also executes a second notification process to notify the driver of vehicle operation to drive the vehicle along an ideal driving line on the road. In the present invention configured in this manner, for drivers with relatively high driving ability, in addition to the notification process regarding the execution of vehicle assistance control, a second notification process to instruct ideal vehicle operation is executed. When vehicle assistance control intervenes, a driver with relatively high driving ability can receive information from the second notification process and improve their own vehicle operation to ideal vehicle operation. As a result, in the present invention, a driver with relatively high driving ability can further improve their driving ability by using the intervention of vehicle assistance control as an opportunity.

The vehicle control device of the present invention can appropriately notify the driver that driving assistance will be performed depending on the state of the driver's driving functions.

FIG. 2 is an explanatory diagram of vehicle control according to an embodiment of the present invention. 1 is a block diagram of a vehicle control device according to an embodiment of the present invention; FIG. 2 is an explanatory diagram showing a processing flow of the vehicle control device according to the embodiment of the present invention. FIG. 1 is an explanatory diagram of a human-machine system according to an embodiment of the present invention. FIG. 1 is an explanatory diagram of a human-machine system according to an embodiment of the present invention. 10 is an explanatory diagram of a notification process according to driving ability and driving risk according to an embodiment of the present invention. FIG. 5A and 5B are explanatory diagrams of a notification process according to driving ability according to an embodiment of the present invention. FIG. 2 is an explanatory diagram of a driver's field of view according to an embodiment of the present invention. FIG. 2 is an explanatory diagram of a driver's gaze point according to an embodiment of the present invention. FIG. 10 is an explanatory diagram of random points according to an embodiment of the present invention. FIG. 10 is an explanatory diagram of saliency AUC according to an embodiment of the present invention. 1 is an explanatory diagram of a driving state of a driver according to an embodiment of the present invention; FIG. 4 is an explanatory diagram of acceleration of a target driving route according to an embodiment of the present invention. FIG. 4 is an explanatory diagram of a resultant acceleration according to an embodiment of the present invention. 3 is a flowchart of a driving assistance control according to an embodiment of the present invention. 3 is a flowchart of a driving assistance control according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicle control device according to an embodiment of the present invention will now be described with reference to the accompanying drawings.
First, an outline of vehicle control provided by a vehicle control device according to an embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is an explanatory diagram of vehicle control.

The vehicle control device 100 of this embodiment (see Figure 2) is configured on the premise that the driver will be the primary driver in operating the vehicle 1. Therefore, the vehicle control device 100 provides an appropriate level of assistance with the operation of the vehicle 1 depending on the driver's condition. That is, in this embodiment, the driving assistance control of the vehicle 1 is provided in principle to fill the gap between the vehicle operation the driver wants to perform and the vehicle operation the driver is capable of performing. For example, the driver's impaired driving function is primarily assisted. Furthermore, the vehicle control device 100 is configured to automatically switch the vehicle 1 to autonomous driving control at predetermined times.

Specifically, if the driver has normal driving ability, the vehicle control device 100 intervenes in vehicle operation and performs driving assistance control (automatic acceleration, automatic braking, automatic steering, etc.) only at specific times. Specific times include, for example, when the driver's driving ability is temporarily impaired (e.g., fatigue, drowsiness) or when the driving environment is relatively difficult (e.g., complex surrounding traffic conditions, complex road geometry, dark surroundings). Furthermore, if the driver (e.g., elderly, MCI) has partially impaired driving ability (e.g., insufficient muscle strength to operate the steering wheel), the vehicle control device 100 compensates for the impaired driving ability. Furthermore, the vehicle control device 100 provides assistance to maintain or restore impaired driving ability, or to further improve driving ability.

On the other hand, if an abnormal sign is detected in which the driver's level of consciousness or driving ability is declining suddenly or over a predetermined period of time (several minutes to several tens of minutes) (for example, when an acute illness develops or the driver is very drowsy), the vehicle control device 100 will perform driving assistance control to maintain safe driving. Furthermore, in the event of an abnormality in which the driver loses consciousness or driving ability, the vehicle control device 100 will execute automatic driving control and perform processing to notify the outside world of an emergency in order to avoid an accident.

Next, the configuration of a vehicle control device according to an embodiment of the present invention will be described with reference to Figure 2. Figure 2 is a block diagram of the vehicle control device. As shown in Figure 2, the vehicle control device 100 mainly includes a controller 10 such as an ECU (Electronic Control Unit), an in-vehicle device 20, a vehicle control system 40, and an information notification device 50.

The in-vehicle device 20 includes an in-vehicle camera 21, an outside-vehicle camera 22, a radar 23, multiple vehicle behavior sensors (vehicle speed sensor 24, acceleration sensor 25, yaw rate sensor 26) that detect the behavior of the vehicle 1, multiple operation detection sensors (steering angle sensor 27, steering torque sensor 28, accelerator opening sensor 29, brake depression amount sensor 30) that detect driver operations, a positioning device 31, a navigation device 32, and an information and communication device 33.

The vehicle control system 40 also includes an engine control system 41, a brake control system 42, and a steering control system 43, which correspond to the vehicle's running, stopping, and turning functions, respectively. The information notification device 50 also includes a display device 51 and an audio output device 52.

The controller 10 is composed of a computer device equipped with a processor 11, a memory 12 that stores various programs and data executed by the processor 11, input/output devices, etc. The controller 10 is configured to output control signals for performing vehicle control (driving assistance control and autonomous driving control) to the vehicle control system 40 and the information notification device 50 based on signals received from the in-vehicle device 20.

The in-vehicle camera 21 captures an image of the driver of the vehicle 1 and outputs image information. The controller 10 determines, based on this image information, in particular, the facial expression and upper body posture of the driver.
The exterior camera 22 captures images of the surroundings of the vehicle 1 (typically, the area in front of the vehicle 1) and outputs image information. Based on this image information, the controller 10 identifies objects outside the vehicle and their positions. The objects include at least traffic participants and boundaries of the roadway. Specifically, the objects include surrounding moving objects (vehicles, pedestrians, etc.) and stationary structures (obstacles, parked vehicles, roadways, lane markings, stop lines, traffic signals, traffic signs, intersections, etc.).

The radar 23 measures the position and speed of objects around the vehicle 1 (typically in front of the vehicle 1). For example, the radar 23 can be a millimeter-wave radar, a laser radar (LIDAR), an ultrasonic sensor, etc.

The vehicle speed sensor 24 detects the speed (vehicle speed) of the vehicle 1. The acceleration sensor 25 detects the acceleration of the vehicle 1. The yaw rate sensor 26 detects the yaw rate generated in the vehicle 1. The steering angle sensor 27 detects the rotation angle (steering angle) of the steering wheel 43b of the vehicle 1. The steering torque sensor 28 detects the rotational torque associated with the rotation of the steering wheel 43b. The accelerator opening sensor 29 detects the amount of depression of the accelerator pedal 41b. The brake depression amount sensor 30 detects the amount of depression of the brake pedal 42b.

The positioning device 31 includes a GPS receiver and/or a gyro sensor and detects the position of the vehicle 1 (current vehicle position information). The navigation device 32 stores map information internally and can provide the map information to the controller 10. The controller 10 can calculate the entire driving route to the destination (including driving lanes, intersections, traffic signals, etc.) based on the map information and current vehicle position information.

The information and communication device 33 communicates with external communication devices. For example, the information and communication device 33 performs vehicle-to-vehicle communication with other vehicles and road-to-vehicle communication with communication devices outside the vehicle, receives various driving information and traffic information (traffic congestion information, speed limit information, etc.), and provides this information to the controller 10.

The engine control system 41 controls the driving force of the engine device (internal combustion engine, electric motor, etc.) of the vehicle 1. The controller 10 drives the engine device and accelerates or decelerates the vehicle 1 by sending a control signal to the engine control device 41a based on input from the accelerator pedal 41b.

The brake control system 42 controls the driving force of the brake device of the vehicle 1. The brake control system 42 includes brake actuators such as a hydraulic pump and a valve unit. The controller 10 drives the brake device and decelerates the vehicle 1 by sending a control signal to the brake control device 42a based on input from the brake pedal 42b.

The steering control system 43 controls the driving force of the steering device of the vehicle 1. The steering control system 43 includes, for example, an electric motor of an electric power steering system. The controller 10 can drive the steering device and change the direction of travel of the vehicle 1 by sending a control signal to the steering control device 43a based on input from the steering wheel 43b.

The display device 51 can visually display support information (visual information) for assisting the driver in vehicle operation in a display area. Specifically, the display device 51 is a HUD. The display area corresponds to the size of the entire windshield or a part of the windshield of the vehicle 1, and the support information is displayed within the field of view of the driver. Alternatively, a liquid crystal display may be used instead of the HUD.
The audio output device 52 is, for example, a speaker, and can provide the driver with assistance information (auditory information) to assist the driver in operating the vehicle.

Next, the processing flow of a vehicle control device according to an embodiment of the present invention will be described with reference to Figure 3. Figure 3 is an explanatory diagram showing the processing flow of a vehicle control device. Specifically, Figure 3 shows that the controller 10 processes input information from the in-vehicle device 20, thereby providing various vehicle controls (driving assistance control, autonomous driving control) and notification controls using the vehicle control system 40 and information notification device 50.

Vehicle control includes ADAS (Advanced Driver Assistance System), automatic acceleration, automatic braking, automatic steering, automatic vehicle stabilization control, automated driving (level 3 or higher), and support processing to improve the driver's driving ability. ADAS includes at least support functions for following the vehicle ahead, preventing collisions with the vehicle ahead, and preventing lane departure. Automatic vehicle stabilization control is a control that stabilizes the vehicle 1's attitude, i.e., vehicle dynamics (pitch, roll, yaw), to prevent skidding, rollover, etc.

The in-vehicle device 20 continuously transmits the acquired information to the controller 10. The controller 10 performs the following calculations or evaluations based on the acquired information.
The controller 10 estimates driving risks in the driving environment around the vehicle 1 based on input information from the outside camera 22, radar 23, vehicle speed sensor 24, acceleration sensor 25, positioning device 31, navigation device 32 (map information), etc. (driving risk assessment process). Specifically, the controller 10 first calculates the positions and speeds of objects around the vehicle 1 (vehicles, pedestrians, boundary lines, guardrails, stop lines, traffic signs, etc.), physical quantities that affect vehicle dynamics (e.g., curve radius of the road, road surface friction coefficient), etc.

Driving risks include collisions with objects and loss or deterioration of vehicle 1's postural stability (for example, spinning or rolling over on a curved road). Risk objects include traffic participants (other vehicles, pedestrians, etc.), guardrails, boundaries, traffic signals (red lights), stop lines, etc. Risk objects also include risk-generating parts of the road (such as clipping points on a curved road). These objects are considered risk objects if there is a possibility that they will cause a risk in the near future (for example, within a specified time period such as 10 seconds) if the current vehicle behavior (vehicle dynamics) continues.

The controller 10 also evaluates the driver's driving ability (driving ability evaluation process). In this embodiment, driving ability includes perceptual ability based on perceptual functions and motor ability based on physical functions. First, the controller 10 evaluates the driver's perceptual ability (perceptual ability evaluation process). Specifically, the controller 10 executes a cognitive ability evaluation process to estimate the driver's ability to recognize perceptual objects outside the vehicle 1 (e.g., traffic participants, obstacles, guardrails, boundaries, traffic signals, stop lines, buildings, and other landmarks) based on image information from the in-vehicle camera 21.

In addition, for the purpose of perceptual ability evaluation, the controller 10 may further execute a judgment ability evaluation process that evaluates the vehicle operation judged by the driver in relation to driving risks, etc., based on information from the accelerator opening sensor 29, brake depression amount sensor 30, steering torque sensor 28, etc. In addition, the driver's level of alertness may be used in the perceptual ability evaluation. For example, the level of alertness can be evaluated based on the degree to which the driver's eyes and/or mouth are open, or the position or posture of the driver's upper body.

The controller 10 also evaluates the driver's physical ability based on information from the accelerator opening sensor 29, brake depression amount sensor 30, steering torque sensor 28, acceleration sensor 25, outside-vehicle camera 22, etc. (physical ability evaluation process). The driver's physical ability is the ability to operate the vehicle 1. Specifically, the controller 10 evaluates the vehicle operations performed by the driver based on the vehicle operations required to travel along an ideal target driving route.

For this reason, the controller 10 calculates a target driving route, which is an ideal driving route. The target driving route includes a target driving trajectory (position information for multiple positions) from the present until a predetermined time later (e.g., 10 seconds later) and vehicle dynamics such as speed at each position on the trajectory. The controller 10 calculates the target driving route so as to achieve predetermined safety and driving efficiency using driving requirements (destination, etc.), driving risk assessment results, etc. The controller 10 can calculate a target driving route, which is an ideal driving line that satisfies predetermined constraints (e.g., lateral acceleration being equal to or less than a predetermined value).

Motoring ability is evaluated, for example, based on the actual acceleration caused by the driver's vehicle operation, relative to the predicted acceleration caused by ideal vehicle operation. That is, the acceleration on the target driving route is compared with the acceleration on the actual driving route. Furthermore, motoring ability may also be evaluated based on factors other than acceleration, such as the positional difference (distance) between the target driving route and the actual driving route, the speed difference between the speed on the target driving route and the actual driving speed, differences in other vehicle dynamics (speed, acceleration, yaw rate, triaxial rotational moment (pitch, yaw, roll), etc.), or a combination of these.

The controller 10 also executes an assistance selection process that provides driving assistance control and other assistance control in response to driving risks, depending on the driver's driving ability. Specifically, when the activation conditions for each driving assistance control are met (for example, when the time to collision with another vehicle reaches X seconds), the controller 10 outputs a control signal to the vehicle control system 40 corresponding to that driving assistance control. Furthermore, the controller 10 executes an alert process and a second alert process using the information alert device 50 when driving assistance control is being executed, based on the results of the perceptual ability assessment and the motor ability assessment.

Next, we will explain the human-machine system consisting of a driver and a vehicle in an embodiment of the present invention. Figures 4 and 5 are explanatory diagrams of the human-machine system in this embodiment.

Figure 4 (A) shows a case where driving assistance control and automated driving control do not intervene. In this case, the driver (human) is equipped with at least cognitive, judgment, and physical functions for driving a vehicle, and uses these driving functions to demonstrate cognitive performance, judgment performance, and driving performance. The driver uses their cognitive function to identify an object (cognitive performance), their judgment function to select or determine the vehicle operation to be performed for the identified object (judgment performance), and their physical function to execute the selected vehicle operation with the appropriate amount and timing (driving performance). Meanwhile, the vehicle is equipped with at least the functions of running, stopping, and turning. The vehicle runs while demonstrating driving performance, braking performance, and handling stability performance by utilizing these driving functions through vehicle operation by the driver.

In this way, when a driver operates a vehicle by demonstrating their cognitive, judgment, and driving abilities, the vehicle exhibits driving performance, braking performance, and handling stability. This allows the vehicle as a human-machine system to achieve safe driving. Conventionally, vehicles have been provided with an interface that mediates between the driver's functions and the vehicle's functions so that the three vehicle capabilities can be efficiently utilized. This improves overall vehicle performance (e.g., braking ability, fuel economy, etc.).

On the other hand, Figure 4 (B) shows a case where the driver's driving ability is extremely low and autonomous driving control intervenes (driving assistance: autonomous driving). In this case, the vehicle takes over all or most of the driver's cognitive functions, decision-making functions, and physical functions. For example, cognitive functions are taken over by on-board cameras, acceleration sensors, radar, etc. Decision-making functions are taken over by the vehicle's computer. Physical functions are taken over by on-board actuators. In exceptional cases, the driver only needs to have the physical functions to issue minimum commands such as starting the engine, and does not need to have most driving functions or driving abilities (driving performance).

Figure 5 (A) also shows a case where the driver (e.g., an elderly person) has medium driving ability and driving assistance control intervenes (safety assurance assistance). Vehicle 1 has a Z function to assist the driver's driving performance. In this example, the driver's perceptual ability (cognitive ability, judgment ability) and motor skills are low, and vehicle 1 assists the driver's low driving ability. As a result, the driver's driving function for low driving ability is compensated for by vehicle 1. Therefore, by continuing to drive, the driver can maintain their own driving ability and extend their driving life.

Figure 5(B) also shows a case where the driver's driving ability is relatively high, but driving assistance control intervenes (driving ability improvement assistance). Vehicle 1 has function X to further improve the driver's driving ability. In this example, driving assistance related to perceptual performance (e.g., gaze guidance control) intervenes, and vehicle 1 provides the driver with advice on driving actions that the driver should perform to improve their driving ability. For example, the driver is instructed on vehicle operations recommended by experienced drivers with high driving ability. This is equivalent to the driver learning driving skills from an experienced driver. Through this processing, the driver can learn exemplary vehicle operations for their weaker cognitive, judgment, or physical functions, thereby improving their driving ability.

Next, with reference to Figures 6 and 7, the notification process when driving assistance control and autonomous driving control intervene will be explained. Figure 6 is an explanatory diagram of the notification process according to driving ability and driving risk, and Figure 7 is an explanatory diagram of the notification process according to driving ability. In Figure 6, the horizontal axis represents the driver's driving ability, and the vertical axis represents driving risk. In Figure 7, the horizontal axis represents perceptual ability, and the vertical axis represents motor ability.

As shown in Figure 6, in this embodiment, when driving ability is generally low (area A of low ability state), even if driving assistance control is executed, notification processing is not executed to notify the driver of the intervention of driving assistance control (driving assistance). For drivers with low driving ability, intervention of driving assistance control occurs relatively frequently. Therefore, in this embodiment, notification processing is not executed for drivers in whom driving assistance control frequently intervenes, thereby avoiding annoyance and confusion for the driver and suppressing a decline in motivation to drive.

On the other hand, if driving ability is generally not low (areas B and C of high ability state), a notification process is executed to notify the driver that driving assistance control will intervene (safety assurance support, driving ability improvement support). If driving ability is moderate (area B), such notification process gives the driver an opportunity to improve their driving ability. Furthermore, if driving ability is relatively high (area C), in addition to the notification process to notify the driver that driving assistance control will intervene, support to improve driving ability (second notification process) is executed. This allows drivers with relatively high driving ability to further improve their driving ability.

In the notification process, the information notification device 50 notifies the driver of the intervention of driving assistance control by visual information (illumination of a lamp, text message, etc.) and/or auditory information (voice). In addition, in the second notification process, the information notification device 50 provides the driver with visual and/or auditory information about vehicle operations for driving the vehicle 1 along an ideal driving line on the road, compared with the driver's actual vehicle operations. For example, the vehicle operations for driving the ideal driving line (target driving route) calculated before the vehicle 1 deviated from the target driving route are displayed.

Furthermore, as shown in FIG. 7 , in this embodiment, notification processing is disabled depending on the level of perceptual ability and motor ability. In this embodiment, a first perceptual threshold TA1 and a second perceptual threshold TA2 are set for perceptual ability, and a first motor threshold TB1, a second motor threshold TB2, and a third motor threshold TB3 are set for motor ability. The first perceptual threshold TA1 is set so that, when the driver is below this threshold, for example, their eyesight is extremely impaired due to a brain disease or their perceptual functions are inactive due to extreme drowsiness. The second perceptual threshold TA2 is set so that, when the driver is below this threshold, for example, their eyesight is impaired and they are prone to becoming distracted. The second perceptual threshold TA2 is set so that the driver's perceptual ability is slightly impaired below the normal level.

Furthermore, the first motor threshold TB1 is set so that, when the first motor threshold TB1 is below this threshold, the driver's arm strength is extremely reduced, for example, due to a brain disease. The second motor threshold TB2 is set so that, when the second motor threshold TB2 is below this threshold, the driver's arm strength is relatively reduced. The third motor threshold TB3 is set so that, when the third motor threshold TB3 is below this threshold, the driver's arm strength is beginning to decrease. The third motor threshold TB3 is set so that the driver's motor ability is slightly reduced from a normal level.

In area A in Figure 7 (corresponding to area A in Figure 6), notification processing is not performed. Area A is when the perceptual ability value TA is equal to or less than the first perceptual threshold TA1 and the motor ability value TB is equal to or less than the first motor threshold TB1, or when the perceptual ability value TA is equal to or less than the second perceptual threshold TA2 and the motor ability value TB is equal to or less than the second motor threshold TB2.

In area B of Figure 7 (corresponding to area B of Figure 6), notification processing is executed. Area B is when the perceptual ability value TA exceeds the second perceptual threshold TA2 and the motor ability value TB exceeds the first motor threshold TB1 but is less than the third motor threshold TB3, or when the motor ability value TB exceeds the second motor threshold TB2 and the perceptual ability value TA exceeds the first perceptual threshold TA1 but is less than the second perceptual threshold TA2.

In area C of Figure 7 (corresponding to area C of Figure 6), the notification process and second notification process are executed. In area C, the perceptual ability value TA is equal to or greater than the second perceptual threshold TA2 and the motor ability value TB is equal to or greater than the third motor threshold TB3.

Next, the perceptual ability assessment of this embodiment will be described with reference to Figures 8 to 11. Figure 8 is an explanatory diagram of the driver's field of view, Figure 9 is an explanatory diagram of the driver's gaze point, Figure 10 is an explanatory diagram of random points, and Figure 11 is an explanatory diagram of saliency AUC.

In this embodiment, saliency is used to evaluate the driver's perceptual ability. "Saliency" is a value that indicates the degree of perceptual stimulus that attracts bottom-up attention, and is a value that changes depending on characteristics such as color, brightness, direction, and movement. For example, as the differences in characteristics such as color, brightness, direction, and movement between any given area in an image and the areas surrounding it become more pronounced, the perceptual stimulus that attracts bottom-up attention becomes stronger, and the saliency in that given area increases. The higher the saliency at any given point (or area) in an image, the more easily people are attracted to that point (or area).

As shown in Figure 8(A), the controller 10 generates a forward image D1 corresponding to the driver's forward field of view image using image information from the exterior camera 22. The forward image D1 includes various visual objects in the forward area outside the vehicle 1 (other vehicles, buildings, trees, forests, walls, clouds, sky, white lines, etc.). Next, the controller 10 performs a saliency map generation process on the forward image D1 to generate a saliency map D2 as shown in Figure 8(B). The saliency map generation process can use well-known techniques such as saliency detection. For example, the controller 10 generates a saliency map for each feature such as color, brightness, direction, and movement, and then adds together the saliency maps for each feature to generate the final saliency map D2.

As shown in Figure 8(B), saliency map D2 shows the distribution of saliency outside vehicle 1. In Figure 8(B), the density of the hatching indicates the magnitude of the saliency (the darker the hatching, the higher the saliency and the more conspicuous it is).

The controller 10 estimates the driver's line of sight from image information from the in-vehicle camera 21 and identifies the gaze point P in the line of sight direction within the saliency map D2. The saliency map D2 and gaze point P are repeatedly calculated every predetermined time (e.g., 0.1 seconds). As shown in Figure 9(A), the gaze point P moves within multiple saliency maps D2 over time.

As shown in Figure 9(B), the controller 10 calculates the time progression of the magnitude of saliency at the gaze point P in each saliency map D2 over a predetermined period TS (e.g., 10 seconds to 10 minutes). Figure 9(B) shows the extent to which the driver directs their gaze toward an attractive perceived object. Meanwhile, the controller 10 sets one random point in each saliency map D2 during the predetermined period TS (see Figure 10(A)) and calculates the magnitude of saliency at each random point (see Figure 10(B)). The magnitude of the saliency at the random point provides a reference for the saliency.

Next, the controller 10 generates an ROC (Receiver Operating Characteristic) curve as shown in FIG. 11. The ROC curve shows the relationship between the "probability that the saliency of the gaze point exceeds the threshold" and the "probability that the saliency of a random point exceeds the threshold." Specifically, the threshold for saliency is gradually changed from the minimum value to the maximum value, and the number of gaze points within a predetermined period TS whose saliency exceeds the threshold is divided by the total number of gaze points within the predetermined period TS to calculate the probability that the saliency of the gaze point exceeds the threshold. The controller 10 also calculates a similar probability for random points. The controller 10 then derives an ROC curve for each threshold based on the combination of the "probability that the saliency of the gaze point exceeds the threshold" and the "probability that the saliency of a random point exceeds the threshold."

In Figure 11, curve C1 is an ROC curve when the driver's gaze tends to be drawn to high saliency areas, and is a convex curve located above the reference line C0 with a slope of 1. On the other hand, curve C2 is an ROC curve when the driver's gaze tends not to be directed toward high saliency areas, and is a concave curve located below the reference line C0. The controller 10 calculates the AUC (Area Under the Curve) value, which is the area under the derived ROC curve. In Figure 11, the AUC value of curve C1 corresponds to the area of the hatched region.

When the ROC curve is C1, the driver is driving in a state of inattention and lack of concentration, and is easily distracted by highly eye-catching perceived objects. The AUC value at this time is larger than the reference value. On the other hand, when the ROC curve is C2, the driver is driving without paying attention to external perceived objects, and is in a state of low alertness, including dozing or fainting. The AUC value at this time is smaller than the reference value. In contrast, when the ROC curve is C0, the magnitude of the saliency at the fixation point and the magnitude of the saliency at the random points match, and the driver is properly viewing the entire external visual field. The AUC value of the reference line C0 is the reference value.

In this embodiment, the perceptual ability value TA is estimated based on the probability that the driver's line of sight will capture a perceptual object outside the vehicle 1. Specifically, the driver's perceptual ability value TA is calculated based on the deviation (area difference ratio) of the driver's AUC value from the reference value (AUC value of the reference line C0: reference AUC value). For example, the perceptual ability value TA is calculated by subtracting the ratio (%) of the absolute value of (AUC value - reference AUC value) to the reference AUC value from 100 (TA = 100 - ABS | AUC value - reference AUC value | / reference AUC value x 100). If the driver's AUC value does not deviate from the reference value, the perceptual ability value TA is "100" (TA = 100). In this embodiment, the first perceptual threshold TA1 is set to "30" and the second perceptual threshold TA2 is set to "50", for example.

Next, the motor skill evaluation of this embodiment will be described with reference to Figures 12 to 14. Figure 12 is an explanatory diagram of the driver's driving state, Figure 13 is an explanatory diagram of the acceleration of the target driving route, and Figure 14 is an explanatory diagram of the resultant acceleration.

Figure 12 shows a vector representation of the actual acceleration at each position when the vehicle 1 is traveling on a curved road 3. In this way, the acceleration vector changes over time. Acceleration information is detected by the acceleration sensor 25. Meanwhile, the controller 10 calculates the target driving route when traveling on the curved road 3, and the target vehicle dynamics (target acceleration, etc.) when traveling on the target driving route. Figure 13 shows the ideal change in acceleration over time on the target driving route (line E0). On the target driving route, the speed and steering angle are calculated so that the maximum value of the lateral acceleration (E2) is twice the maximum value of the longitudinal acceleration (line E1).

Figure 14 shows the resultant acceleration vector Gk (k = 1 to n) at each position on the actual driving route, superimposed on the original. The resultant acceleration vector has a magnitude and direction, and is calculated by combining longitudinal acceleration and lateral acceleration. Figure 14 also shows the range of the ideal target acceleration vector on the target driving route (dashed line GT: the range where the vector tips are connected).

In this embodiment, the athletic ability value TB is estimated based on the acceleration generated in the vehicle 1 due to the driver's vehicle operation. Specifically, the magnitude of the driver's athletic ability is calculated based on the deviation of the actual acceleration from the target acceleration of the target driving route during driving for a predetermined time TM. Specifically, the controller 10 calculates the athletic ability value TB by integrating the acceleration difference (absolute value) between the actual acceleration generated by the driver's speed operation (accelerator pedal and brake pedal) and steering operation (steering wheel) and the target acceleration (ideal acceleration) over the predetermined time TM. For example, the athletic ability value TB is calculated by subtracting the average value of the ratio (%) of the acceleration difference to the magnitude of the target acceleration from 100 (TB = 100 - AVE [acceleration difference (absolute value) / target acceleration] x 100). If there is no acceleration difference, the athletic ability value is "100." In this embodiment, for example, the first movement threshold TB1 is set to "30", the second movement threshold TB2 is set to "50", and the third movement threshold TB3 is set to "70".

Next, the processing flow of the driving assistance control of the vehicle control device according to an embodiment of the present invention will be described. Figures 15 and 16 are flowcharts of the driving assistance control. The controller 10 repeatedly performs the processing flow of Figure 15 from the start of engine operation of the vehicle 1 until the end of driving (for example, every 0.1 seconds).

First, as shown in FIG. 15, the controller 10 acquires current information from the in-vehicle device 20 at predetermined time intervals (e.g., every 0.1 seconds) (S1), and estimates driving ability using information collected over the predetermined time period up to the present (S2). In this process, the controller 10 performs processes such as driving risk assessment, perceptual ability assessment, and motor ability assessment based on the acquired information, and calculates driving ability values (perceptual ability value TA and motor ability value TB).

The controller 10 executes a process of comparing the driver's perceptual ability value TA and motor ability value TB with thresholds (S3 to S6). If the perceptual ability value TA is equal to or less than the first perceptual threshold TA1 (S3: Yes), if the motor ability value TB is equal to or less than the first motor threshold TB1 (S4: Yes), or if the perceptual ability value TA is equal to or less than the second perceptual threshold TA2 and the motor ability value TB is equal to or less than the second motor threshold TB2 (S5: Yes), the controller 10 sets the support flag F to "1" (S7). That is, in area A of FIG. 7, the support flag F is set to "1."

Furthermore, if the perceptual ability value TA is equal to or greater than the second perceptual threshold TA2 and the motor ability value TB is equal to or greater than the third motor threshold TB3 (S6: Yes), the controller 10 sets the support flag F to "3" (S9). That is, in area C of FIG. 7, the support flag F is set to "3".

Furthermore, if the perceptual ability value TA is equal to or greater than the second perceptual threshold TA2 and the motor ability value TB is not equal to or greater than the third motor threshold TB3 (S6: No), the controller 10 sets the support flag F to "2" (S8). That is, in area B of FIG. 7, the support flag F is set to "2".

Next, the controller 10 records the assistance flag F in the assistance flag database in the memory 12 (S10). Furthermore, when driving ends (when the engine is off or the vehicle speed is zero), the controller 10 selects the assistance flag F with the greatest number ("1," "2," or "3") from among the assistance flags F recorded in the assistance flag database and sets this as the recommended assistance flag FR.

Next, the controller 10 repeatedly executes the processing flow of FIG. 16 over time (e.g., every 0.1 seconds) while the vehicle 1 is traveling. First, the controller 10 determines whether the activation conditions for each driving assistance control are met (S11). If none of the activation conditions for driving assistance control are met (S11: No), the processing ends. On the other hand, if the activation conditions for any of the driving assistance controls are met (S11: Yes), the controller 10 determines whether the recommended assistance flag FR is "1," "2," or "3" (S12, S13).

If the recommended assistance flag FR is "1" (S12: Yes), the controller 10 executes the driving assistance process (S14) and ends the process. In the driving assistance process, the controller 10 executes driving assistance control for which the activation conditions are met (S14a). Therefore, the controller 10 sends the necessary control signals to the vehicle control system 40. Meanwhile, the controller 10 does not execute notification processing to notify the driver that driving assistance control has been executed. Although the driver does not receive visual and/or auditory information about the driving assistance control from the notification device 50, they can recognize that driving assistance control has been executed from the behavior of the vehicle 1.

Alternatively, this driving assistance process may be automated driving control to the destination in addition to vehicle assistance control when the activation conditions are met. The destination may be, for example, a destination input by the driver into the vehicle control device 100. The destination may also be the side of a road on a driving path for making an emergency stop. In this case, the vehicle 1 will travel safely to the destination using automated driving control, regardless of the driver's condition.

Also, if the recommended support flag FR is "2" (S13: Yes), the controller 10 executes the safety assurance support process (S15) and ends the process. In the safety assurance support process, the controller 10 executes driving support control (S15a) for which the activation conditions are met, and also executes notification process (S15b) regarding the intervention of driving support control. The notification process allows the driver to know that driving support control has intervened.

Also, if the recommended assistance flag FR is "3" (S13: No), the controller 10 executes the driving ability improvement assistance process (S16) and ends the process. In the driving ability improvement assistance process, the controller 10 executes driving assistance control (S16a) when the activation conditions are met, and also executes a notification process (S16b) regarding the intervention of driving assistance control. Furthermore, the controller 10 executes a second notification process (S16c) that notifies the driver of vehicle operations to ensure that the vehicle 1 travels along an ideal driving line on the driving road. The ideal driving line on the driving road is the target driving route. In the second notification process, the controller 10 provides the driver with information indicating, for example, the ideal amount of operation of the operating parts (accelerator pedal 41b, brake pedal 42b, steering wheel 43b, etc.) and the amount of operation by the driver, using the information notification device 50.

In the processing flow of FIG. 15, the recommended support flag FR may be repeatedly updated with the value of the support flag F while the vehicle is traveling. In this case, the recommended support flag FR changes while the vehicle is traveling. Then, the controller 10 may execute the processing flow of FIG. 16 while the vehicle is traveling using the recommended support flag FR, which changes over time.

The operation of the vehicle control device 100 according to the embodiment of the present invention will be described below.
This embodiment is a vehicle control device 100 that estimates driving risks that may occur to vehicle 1 due to the driving environment of vehicle 1, executes driving assistance control (14a, 15a, 16a) on vehicle 1 to avoid the occurrence of the driving risks, and executes notification processing (15b, 16b) to notify the driver of vehicle 1 of the execution of driving assistance control, and is characterized in that the vehicle control device 100 executes a driving ability evaluation processing (S2) that estimates driving ability values (TA, TB) that indicate the magnitude of the driver's driving ability, and executes the notification processing (15b, 16b) when the driving ability values (TA, TB) are in a high ability state (areas B, C) greater than a predetermined threshold value when the driving ability values (TA, TB) are in a low ability state (area A) less than the predetermined threshold value when the vehicle control device 100 executes driving assistance control.

In this embodiment, which is configured as described above, the notification process is disabled for drivers with low driving ability, as the intervention of driving assistance control occurs relatively frequently. This prevents the driver from feeling annoyed by the frequent notification process or from becoming confused by the notification process. On the other hand, in this embodiment, for drivers with medium or relatively high driving ability, the notification of the intervention of driving assistance control can encourage the driver to voluntarily maintain and improve their driving ability.

Furthermore, in this embodiment, the driving ability value preferably includes a perceptual ability value TA representing the level of perceptual ability to recognize perceptual objects, including traffic participants outside vehicle 1, and a motor ability value TB representing the level of motor ability to operate vehicle 1. In this embodiment configured in this manner, driving ability is distinguished into perceptual ability and motor ability, and notification processing can be performed appropriately depending on the combination of the levels of these abilities.

In addition, in this embodiment, the perceptual ability value TA is preferably calculated based on the probability that the driver's line of sight will capture a perceptual object outside the vehicle 1, and the motor ability value TB is estimated based on the acceleration caused to the vehicle 1 by the driver's vehicle operation. In this embodiment configured in this manner, the perceptual ability value and motor ability value can be calculated and updated relatively easily.

In this embodiment, the low capacity state (area A) is preferably
When the perception ability value TA is equal to or less than the first perception threshold TA1, or
When the motor ability value TB is equal to or lower than the first motor threshold TB1, or
The high ability state (areas B and C) is when the perceptual ability value TA is equal to or less than the second perceptual threshold TA2, which is set to a value greater than the first perceptual threshold TA1, and the motor ability value TB is equal to or less than the second motor threshold TB2, which is set to a value greater than the first motor threshold TB1.
When the perceptual ability value TA exceeds the first perceptual threshold TA1 and the motor ability value TB exceeds the second motor threshold TB2, or
- This is the case where the perceptual ability value TA exceeds the second perceptual threshold TA2 and the motor ability value TB exceeds the first motor threshold TB1.
In this embodiment configured as described above, by setting a threshold value, it is possible to more appropriately execute the notification process (15b, 16b) according to the combination of the magnitudes of the respective abilities.

Furthermore, in this embodiment, preferably, in the low-capability state (S12: Yes), the vehicle control device 100 does not execute notification processing, but executes driving assistance control (S14a) to automatically drive the vehicle 1 to a predetermined destination. In this embodiment configured in this manner, a driver with reduced driving ability can be safely driven to their destination by automatic driving.

In the present embodiment, preferably, in the high capacity state (S13: Yes), the vehicle control device 100
When the perceptual ability value TA exceeds the first perceptual threshold TA1 but is less than the second perceptual threshold TA2, and the motor ability value TB exceeds the second motor threshold TB2, or
When the motor ability value TB exceeds the first motor threshold TB1 but is less than the third motor threshold TB3, which is set to a value greater than the second motor threshold TB2, and when the perceptual ability value TA exceeds the second perceptual threshold TA2, a notification process (S15b) is executed. In this embodiment configured as described above, the notification process (S15b) regarding the execution of vehicle assistance control is executed for a driver with average driving ability, so that the driver can use the intervention of vehicle assistance control as motivation to maintain or improve their driving ability.

In addition, preferably in this embodiment, in the high ability state (S13: No), when the perceptual ability value TA is equal to or greater than the second perceptual threshold TA2 and the motor ability value TB is equal to or greater than the third motor threshold TB3, which is set to a value greater than the second motor threshold TB2, the vehicle control device 100 executes a notification process (S16b) and a second notification process (S16c) that notifies the driver of vehicle operation to drive the vehicle 1 along an ideal driving line on the road. In this embodiment configured as above, for drivers with relatively high driving ability, in addition to the notification process (S16b) regarding the execution of vehicle assistance control, a second notification process (S16c) that instructs ideal vehicle operation is executed. When vehicle assistance control intervenes, a driver with relatively high driving ability can receive information from the second notification process and improve their own vehicle operation to ideal vehicle operation. As a result, in this embodiment, a driver with relatively high driving ability can further improve their driving ability by using the intervention of vehicle assistance control as an opportunity.

REFERENCE SIGNS LIST 1 Vehicle 10 Controller 20 In-vehicle device 40 Vehicle control system 50 Information notification device 100 Vehicle control device TA Perceptual ability value TA1 First perceptual threshold TA2 Second perceptual threshold TB Motor ability value TB1 First motor threshold TB2 Second motor threshold TB3 Third motor threshold

Claims (5)

A vehicle control device that estimates a driving risk that may occur to a vehicle due to a driving environment of the vehicle, executes driving assistance control for the vehicle so as to avoid the occurrence of the driving risk, and executes a notification process to notify a driver of the vehicle of the execution of the driving assistance control,
the vehicle control device executes a driving ability evaluation process to estimate a driving ability value that indicates the magnitude of the driver's driving ability, and when the driving assistance control is being executed, executes the notification process when the driving ability value is in a high ability state that is greater than a predetermined threshold, but does not execute the notification process when the driving ability value is in a low ability state that is equal to or less than the predetermined threshold,
the driving ability value includes a perceptual ability value representing a magnitude of perceptual ability to recognize perceptual objects including traffic participants outside the vehicle, and a motor ability value representing a magnitude of motor ability to perform vehicle operation of the vehicle;
the perception ability value is calculated according to a probability that the driver's line of sight captures a perception object outside the vehicle;
A vehicle control device in which the athletic ability value is calculated according to the acceleration caused in the vehicle by the driver's vehicle operation . The low capacity state is
If the perception ability value is equal to or less than a first perception threshold, or
When the motor ability value is equal to or less than a first motor threshold, or
the perceptual ability value is equal to or less than a second perceptual threshold set to a value greater than the first perceptual threshold, and the motor ability value is equal to or less than a second motor threshold set to a value greater than the first motor threshold,
The high capacity state is
When the perceptual ability value exceeds the first perceptual threshold and the motor ability value exceeds the second motor threshold, or
The vehicle control device according to claim 1 , wherein the perceptual ability value exceeds the second perceptual threshold and the motor ability value exceeds the first motor threshold. The vehicle control device according to claim 1 or 2 , wherein, in the low capacity state, the vehicle control device does not execute the notification process, and executes the driving assistance control so as to automatically drive the vehicle to a predetermined destination. In the high capacity state, the vehicle control device
The perceptual ability value exceeds the first perceptual threshold but is less than the second perceptual threshold, and the motor ability value exceeds the second motor threshold; or
When the motor ability value exceeds the first motor threshold but is less than a third motor threshold set to a value greater than the second motor threshold, and the perceptual ability value exceeds the second perceptual threshold,
The vehicle control device according to claim 2 , which executes the notification process. In the high capacity state, the vehicle control device
3. The vehicle control device of claim 2, wherein when the perceptual ability value is equal to or greater than the second perceptual threshold and the motor ability value is equal to or greater than a third motor threshold set to a value greater than the second motor threshold, the notification process is executed and a second notification process is executed to notify the driver of vehicle operations to cause the vehicle to travel along an ideal driving line on the road.