Driving assistance apparatus

1. A driving assistance apparatus configured to start deceleration assistance for a driver's vehicle based on a distance between the driver's vehicle and a deceleration-triggering object ahead of the driver's vehicle, the driving assistance apparatus comprising:

a start condition determination unit configured to determine whether a preset deceleration assistance start condition is satisfied based on a distance between the driver's vehicle and a first deceleration-triggering object ahead of the driver's vehicle;

a driving assistance unit configured to start the deceleration assistance for the driver's vehicle against the first deceleration-triggering object when the start condition determination unit determines that the deceleration assistance start condition is satisfied;

a termination condition determination unit configured to determine whether a preset deceleration assistance termination condition is satisfied based on the distance between the driver's vehicle and the first deceleration-triggering object, or based on a speed of the driver's vehicle during the deceleration assistance for the driver's vehicle against the first deceleration-triggering object;

a notification unit configured to issue a deceleration assistance termination notification to a driver of the driver's vehicle when the termination condition determination unit determines that the deceleration assistance termination condition is satisfied;

a second deceleration-triggering object detection unit configured to determine whether a second deceleration-triggering object is detected ahead of the driver's vehicle during the deceleration assistance for the driver's vehicle against the first deceleration-triggering object; and

a quick resumption condition determination unit configured to determine, when the termination condition determination unit determines that the deceleration assistance termination condition for the first deceleration-triggering object is satisfied and the second deceleration-triggering object detection unit determines that the second deceleration-triggering object is detected, whether a preset quick resumption condition is satisfied based on a distance between the driver's vehicle and the second deceleration-triggering object, and based on a relative speed between the driver's vehicle and the second deceleration-triggering object, wherein

the notification unit is configured not to issue the deceleration assistance termination notification when the quick resumption condition determination unit determines that the quick resumption condition is satisfied, even in a case where the termination condition determination unit determines that the deceleration assistance termination condition for the first deceleration-triggering object is satisfied.

2. The driving assistance apparatus according to claim 1 , wherein the quick resumption condition determination unit is configured to:

estimate a remaining time until the deceleration assistance start condition for the second deceleration-triggering object is satisfied based on the distance between the driver's vehicle and the second deceleration-triggering object, and based on the relative speed between the driver's vehicle and the second deceleration-triggering object; and

determine that the quick resumption condition is satisfied when the remaining time is shorter than a preset time determination threshold.

3. The driving assistance apparatus according to claim 1 , wherein the quick resumption condition determination unit is configured to:

estimate a remaining traveling distance until the deceleration assistance start condition for the second deceleration-triggering object is satisfied based on the distance between the driver's vehicle and the second deceleration-triggering object, and based on the relative speed between the driver's vehicle and the second deceleration-triggering object; and

determine that the quick resumption condition is satisfied when the remaining traveling distance is shorter than a preset distance determination threshold.

4. The driving assistance apparatus according to claim 1 , wherein:

the second deceleration-triggering object detection unit is configured to recognize a type of the detected second deceleration-triggering object; and

the quick resumption condition determination unit is configured to use, as the quick resumption condition, a different condition dependent on the type of the second deceleration-triggering object.

5. The driving assistance apparatus according to claim 1 , wherein:

the second deceleration-triggering object detection unit is configured to recognize a type of the detected second deceleration-triggering object;

the quick resumption condition determination unit is configured to

estimate a remaining time until the deceleration assistance start condition for the second deceleration-triggering object is satisfied based on the distance between the driver's vehicle and the second deceleration-triggering object, and based on the relative speed between the driver's vehicle and the second deceleration-triggering object,

determine that the quick resumption condition is satisfied when the type of the second deceleration-triggering object is a preceding vehicle and the remaining time is shorter than a preset vehicle time determination threshold, and

determine that the quick resumption condition is satisfied when the type of the second deceleration-triggering object is a stationary object and the remaining time is shorter than a preset stationary-object time determination threshold; and

the vehicle time determination threshold is smaller than a time determination threshold for the stationary object.

6. The driving assistance apparatus according to claim 1 , wherein:

the second deceleration-triggering object detection unit is configured to recognize a type of the detected second deceleration-triggering object;

the quick resumption condition determination unit is configured to

estimate a remaining traveling distance until the deceleration assistance start condition for the second deceleration-triggering object is satisfied based on the distance between the driver's vehicle and the second deceleration-triggering object, and based on the relative speed between the driver's vehicle and the second deceleration-triggering object,

determine that the quick resumption condition is satisfied when the type of the second deceleration-triggering object is a preceding vehicle and the remaining traveling distance is shorter than a preset vehicle distance determination threshold, and

determine that the quick resumption condition is satisfied when the type of the second deceleration-triggering object is a stationary object and the remaining traveling distance is shorter than a preset stationary-object distance determination threshold; and

the vehicle distance determination threshold is smaller than the stationary-object distance determination threshold.

7. A driving assistance apparatus configured to start deceleration assistance for a driver's vehicle based on a distance between the driver's vehicle and a deceleration-triggering object ahead of the driver's vehicle, the driving assistance apparatus comprising:

a start condition determination unit configured to determine whether a preset deceleration assistance start condition is satisfied based on a distance between the driver's vehicle and a first deceleration-triggering object, the first deceleration-triggering object being a traffic signal or a stop line ahead of the driver's vehicle;

a driving assistance unit configured to start the deceleration assistance for the driver's vehicle against the first deceleration-triggering object when the start condition determination unit determines that the deceleration assistance start condition is satisfied;

a termination condition determination unit configured to determine whether a preset deceleration assistance termination condition is satisfied based on a vehicle speed of the driver's vehicle during the deceleration assistance for the driver's vehicle against the first deceleration-triggering object;

a notification unit configured to issue a deceleration assistance termination notification to a driver of the driver's vehicle when the termination condition determination unit determines that the deceleration assistance termination condition is satisfied;

a second deceleration-triggering object detection unit configured to determine whether a second deceleration-triggering object is detected during the deceleration assistance for the driver's vehicle against the first deceleration-triggering object, the second deceleration-triggering object being a preceding vehicle traveling ahead of the driver's vehicle; and

a quick resumption condition determination unit configured to determine whether a preset quick resumption condition is satisfied when the termination condition determination unit determines that the deceleration assistance termination condition for the first deceleration-triggering object is satisfied and the second deceleration-triggering object detection unit determines that the second deceleration-triggering object is detected, wherein

the quick resumption condition determination unit is configured to determine that the quick resumption condition is satisfied when the second deceleration-triggering object is located behind the stop line being the first deceleration-triggering object or behind a stop line associated with the traffic signal being the first deceleration-triggering object, and

the notification unit is configured not to issue the deceleration assistance termination notification when the quick resumption condition determination unit determines that the quick resumption condition is satisfied, even in a case where the termination condition determination unit determines that the deceleration assistance termination condition for the first deceleration-triggering object is satisfied.

8. A driving assistance apparatus configured to start deceleration assistance for a driver's vehicle based on a distance between the driver's vehicle and a deceleration-triggering object ahead of the driver's vehicle, the driving assistance apparatus comprising a controller configured to:

determine whether a preset deceleration assistance start condition is satisfied based on a distance between the driver's vehicle, and based on a first deceleration-triggering object ahead of the driver's vehicle;

start the deceleration assistance for the driver's vehicle against the first deceleration-triggering object when determining that the deceleration assistance start condition is satisfied;

determine whether a preset deceleration assistance termination condition is satisfied based on the distance between the driver's vehicle and the first deceleration-triggering object, or based on a speed of the driver's vehicle during the deceleration assistance for the driver's vehicle against the first deceleration-triggering object;

issue a deceleration assistance termination notification to a driver of the driver's vehicle when determining that the deceleration assistance termination condition is satisfied;

determine whether a second deceleration-triggering object is detected ahead of the driver's vehicle during the deceleration assistance for the driver's vehicle against the first deceleration-triggering object; and

determine, when determining that the deceleration assistance termination condition for the first deceleration-triggering object is satisfied and determining that the second deceleration-triggering object is detected, whether a preset quick resumption condition is satisfied based on a distance between the driver's vehicle and the second deceleration-triggering object, and based on a relative speed between the driver's vehicle and the second deceleration-triggering object, wherein

the controller is configured not to issue the deceleration assistance termination notification when the controller determines that the quick resumption condition is satisfied, even in a case where the controller determines that the deceleration assistance termination condition for the first deceleration-triggering object is satisfied.