Driver monitoring device and method using criterion based on surrounding vehicles

1 . A driver monitoring device comprising a processor configured to:

acquire surrounding vehicle information which is information showing stopped or decelerating surrounding vehicles in a surrounding region of a host vehicle, surrounding road environment information which is information showing a road environment in the surrounding region, and driver line-of-sight direction information which is information showing a direction of a line-of-sight of a driver of the host vehicle;

perform autonomous driving or driving assistance of the host vehicle based on the surrounding vehicle information and the surrounding road environment information;

determine whether the driver's visual recognition in a direction of travel of the host vehicle is sufficient;

alert the driver when the driver's visual recognition in the direction of travel of the host vehicle is not sufficient;

change recognition determination criterion used for determining that the driver's visual recognition in the direction of travel of the host vehicle is not sufficient; and

change the recognition determination criterion based on the number of the stopped or decelerating surrounding vehicles in the surrounding region by performing at least one of: shortening a recognition determination time, narrowing a line-of-sight region, or broadening an object region,

wherein the processor is configured to detect multiple stopped surrounding vehicles as on-road parked vehicles arranged in parallel along the direction of travel of the host vehicle, and, in response, change the recognition determination time based on a cumulative count of the on-road parked vehicles.

2 . The driver monitoring device according to claim 1 , wherein

as the recognition determination criterion, the recognition determination time, which is a time when the driver must gaze at the direction of travel of the host vehicle, is used; and

wherein the processor is configured to shorten the recognition determination time based on the number of the stopped or decelerating surrounding vehicles in the surrounding region.

3 . The driver monitoring device according to claim 1 , wherein

as the recognition determination criterion, the line-of-sight region, which is a region in the direction of travel of the host vehicle which the driver must gaze at, is used;

wherein the processor is configured to narrow the line-of-sight region greaterbased on the number of the stopped or decelerating surrounding vehicles in the surrounding region; and

the processor is configured to determine that the driver's visual recognition in the direction of travel of the host vehicle is not sufficient if the region which the driver is gazing at during the recognition determination time, which is a time when the driver must gaze at the direction of travel of the host vehicle, does not include the line-of-sight region.

4 . The driver monitoring device according to claim 3 ,

wherein the line-of-sight region includes a region adjoining a stopped surrounding vehicle in the surrounding region where a moving body is positioned on an opposite side of the host vehicle across the stopped surrounding vehicle in the surrounding region.

5 . The driver monitoring device according to claim 3 ,

wherein the line-of-sight region includes a region positioned between a decelerating surrounding vehicle in the surrounding region and an on-road parked surrounding vehicle in the surrounding region where a moving body is positioned between the decelerating surrounding vehicle in the surrounding region and the on-road parked surrounding vehicle in the surrounding region.

6 . The driver monitoring device according to claim 1 , wherein

as the recognition determination criterion, the object region, which is a region in the direction of travel of the host vehicle which the driver must gaze at, is used;

wherein the processor is configured to broaden the object region based on the number of the stopped or decelerating surrounding vehicles in the surrounding region; and

the processor is configured to determine that the driver's visual recognition in the direction of travel of the host vehicle is not sufficient if the region which the driver is gazing at during the recognition determination time, which is time when the driver must gaze at the direction of travel of the host vehicle, is narrower than the object region.

7 . The driver monitoring device according to claim 6 , wherein

the object region broadened by the processor is a region combining a stopped vehicle region, which is a region of a stopped surrounding vehicle in the surrounding region, and an adjoining region, which is a region adjoining the stopped vehicle region, and

the adjoining region is a region where a moving body is positioned.

8 . The driver monitoring device according to claim 6 , wherein

the object region broadened by the processor is a region combining a decelerating vehicle region, which is a region of a decelerating surrounding vehicle in the surrounding region, and an intermediate region, which is a region positioned between the decelerating vehicle region in the surrounding region and an on-road parked surrounding vehicle in the surrounding region, and

the intermediate region is a region where a moving body is positioned.

9 . A driver monitoring method comprising:

acquiring surrounding vehicle information which is information showing stopped or decelerating vehicles in a surrounding region of a host vehicle, surrounding road environment information which is information showing a road environment in the surrounding region, and driver line-of-sight direction information which is information showing a direction of a line-of-sight of a driver of the host vehicle; and

performing autonomous driving or driving assistance of the host vehicle based on the surrounding vehicle information and the surrounding road environment information, wherein

performing autonomous driving or driving assistance of the host vehicle includes determining whether the driver's visual recognition in a direction of travel of the host vehicle is sufficient;

alerting the driver when the driver's visual recognition in the direction of travel of the host vehicle is not sufficient; and

changing recognition determination criterion used for determining that the driver's visual recognition in the direction of travel of the host vehicle is not sufficient,

wherein the recognition determination criterion is changed based on the number of the stopped or decelerating surrounding vehicles in the surrounding region by performing at least one of: shortening a recognition determination time, narrowing a line-of-sight region, or broadening an object region,

wherein the method includes detecting multiple stopped surrounding vehicles as on- road parked vehicles arranged in parallel along the direction of travel of the host vehicle, and, in response, changing the recognition determination time based on a cumulative count of the on-road parked vehicles.

10 . A non-transitory recording medium having recorded thereon a computer program for causing a processor to execute a process comprising:

acquiring surrounding vehicle information which is information showing stopped or decelerating vehicles in a surrounding region of a host vehicle, surrounding road environment information which is information showing a road environment in the surrounding region, and driver line-of-sight direction information which is information showing a direction of a line-of-sight of a driver of the host vehicle; and

performing autonomous driving or driving assistance of the host vehicle based on the surrounding vehicle information and the surrounding road environment information,

wherein

performing autonomous driving or driving assistance of the host vehicle includes

determining whether the driver's visual recognition in a direction of travel of the host vehicle is sufficient;

alerting the driver when the driver's visual recognition in the direction of travel of the host vehicle is not sufficient; and

changing recognition determination criterion used for determining that the driver's visual recognition in the direction of travel of the host vehicle is not sufficient,

wherein the recognition determination criterion is changed based on the number of the stopped or decelerating surrounding vehicles in the surrounding region by performing at least one of: shortening a recognition determination time, narrowing a line-of-sight region, or broadening an object region,

wherein the process includes detecting multiple stopped surrounding vehicles as on-road parked vehicles arranged in parallel along the direction of travel of the host vehicle, and, in response, changing the recognition determination time based on a cumulative count of the on-road parked vehicles.