Control device, control method, and storage medium

A control method, wherein a control device executes:

• recognizing a situation of surroundings of a host vehicle;
• automatically controlling at least steering of the host vehicle to perform branch control on the basis of the recognized surroundings situation, the branch control including lane keeping control for causing the host vehicle to travel so that the host vehicle does not deviate from a first lane on a main road on which the host vehicle is travelling, and lane change control for causing the host vehicle to change lanes to a second lane on a branching road branching off from the main road, a first number of lanes on the branch road being less than a second number of lanes on the main road, and
• stopping the lane keeping control and the lane change control when an event occurs in which the branch control is not executable after starting the lane change of the host vehicle from the first lane on the main road to the second lane on the branch road on the basis of the lane change control, in a case in which the host vehicle plans on traveling from the first lane to the second lane through execution of the lane keeping control and the lane change control,
• wherein the control device executes:
• decelerating the host vehicle in order to change the lane from the first lane on the main road to the second lane on the branch road when the host vehicle reaches a predetermined distance before a start position at which the host vehicle starts changing lanes, and
• controlling a speed of the host vehicle so that the speed of the host vehicle at the time of occurrence of the event is maintained and controlling the host vehicle so that the host vehicle does not deviate from the first lane when the event occurs after the deceleration and before start of the lane change control.

A non-transitory computer storage medium having a program stored therein, the program causing a control device to execute:

• recognizing a situation of surroundings of a host vehicle;
• automatically controlling at least steering of the host vehicle to perform branch control on the basis of the recognized surroundings situation, the branch control including lane keeping control for causing the host vehicle to travel so that the host vehicle does not deviate from a first lane on a main road on which the host vehicle is traveling, and lane change control for causing the host vehicle to change lanes to a second lane on a branch road branching off from the main road, a first number of lanes on the branch road being less than a second number of lanes on the main road, and
• stopping the lane keeping control and the lane change control when an event occurs in which the branch control is not executable after starting the lane change of the host vehicle from the first lane on the main road to the second lane on the branch road on the basis of the lane change control, in a case in which the host vehicle plans on traveling from the first lane to the second lane through execution of the lane keeping control and the lane change control,
• wherein the program causing a control device to execute:
• decelerating the host vehicle in order to change the lane from the first lane on the main road to the second lane on the branch road when the host vehicle reaches a predetermined distance before a start position at which the host vehicle starts changing lanes, and
• controlling a speed of the host vehicle so that the speed of the host vehicle at the time of occurrence of the event is maintained and controlling the host vehicle so that the host vehicle does not deviate from the first lane when the event occurs after the deceleration and before start of the lane change control.