Vehicle control device and vehicle control method

A vehicle control device comprising:

• a processor;
• and
• a memory that stores a program that, when executed by the processor, facilitate performance of the program comprising:
• recognizing a surrounding situation of a vehicle;
• controlling steering and acceleration/deceleration of the vehicle independently of an operation of a driver of the vehicle;
• and
• deciding on any one of a plurality of driving modes, including a first driving mode and a second driving mode, as a driving mode of the vehicle, resulting in a decided driving mode, and
• changing the driving mode of the vehicle from the decided driving mode to a driving mode in which a number of tasks imposed on the driver is more than the number of tasks imposed on the driver in the decided driving mode when a task associated with the decided driving mode is not executed by the driver, the second driving mode being a driving mode in which the number of tasks imposed on the driver is less than the number of tasks imposed on the driver in the first driving mode, some of the plurality of driving modes including at least the second driving mode being controlled by a driving controller,
• when a sign existing within a reference range of a route along which the vehicle travels is recognized, the performance of the program further comprises:
• based on the driving mode of the vehicle being the second driving mode and based on a first determination that a number of signs recognized by the recognizer exceeds a first reference value, changing the driving mode of the vehicle from the second driving mode to the first driving mode, and
• wherein the first reference value is updated when map information including at least information of a position of a sign installed in a lane on a map has been updated.

A vehicle control method comprising:

• recognizing, by a computer mounted in a vehicle, a surrounding situation of the vehicle;
• controlling, by the computer, steering and acceleration/deceleration of the vehicle independently of an operation of a driver of the vehicle;
• deciding, by the computer, on any one of a plurality of driving modes, including a first driving mode and a second driving mode, as a driving mode of the vehicle, resulting in a decided driving mode, the second driving mode being a driving mode in which a number of tasks imposed on the driver is less than the number of tasks imposed on the driver in the first driving mode, some of the plurality of driving modes including at least the second driving mode being performed by controlling the steering and the acceleration/deceleration of the vehicle independently of the operation of the driver of the vehicle;
• changing, by the computer, the driving mode of the vehicle from the decided driving mode to a driving mode in which the number of tasks imposed on the driver is more than the number of tasks imposed on the driver in the decided driving mode when a task associated with the decided driving mode is not executed by the driver;
• recognizing, by the computer, a sign existing within a reference range of a route along which the vehicle travels at the time of recognition;
• based on the driving mode of the vehicle being the second driving mode and based on a first determination that a number of recognized signs exceeds a first reference value, changing, by the computer, the driving mode of the vehicle from the second driving mode to the first driving mode, and
• based on the driving mode of the vehicle being the second driving mode and based on a second determination that a difference degree between the number of recognized signs and a number of signs installed in a lane on a map of the reference range indicated in map information including sign information does not satisfy a condition, changing, by the computer, the driving mode from the second driving mode to the first driving mode.