Vehicle control system

1. A vehicle control system that controls a vehicle performing automated driving, the vehicle control system comprising at least one processor configured to:

execute vehicle travel control that controls steering, acceleration, and deceleration of the vehicle such that the vehicle follows a target trajectory;

generate a first target trajectory as the target trajectory for the automated driving of the vehicle;

determine whether or not an activation condition of travel assist control is satisfied, wherein the travel assist control controls at least one of the steering, the acceleration, and the deceleration for at least one of improving safety or comfort of travel of the vehicle, reducing discomfort of an occupant of the vehicle, and stabilizing behavior of the vehicle;

generate a second target trajectory as the target trajectory for the travel assist control when the activation condition is satisfied;

when the second target trajectory is generated during the automated driving, determine whether a priority condition for giving priority to the second target trajectory is satisfied; and

when the second target trajectory is generated during the automated driving and the priority condition is satisfied:

combine the first target trajectory and the second target trajectory to generate a control target trajectory, the combination giving more weight to the second target trajectory than to the first target trajectory, and

execute the vehicle travel control such that the vehicle follows the control target trajectory,

wherein the priority condition includes that a second steering direction required for the vehicle to follow the second target trajectory is opposite to a first steering direction required for the vehicle to follow the first target trajectory.

2. The vehicle control system according to claim 1 , wherein the priority condition further includes that the acceleration is required for the vehicle to follow the first target trajectory and the deceleration is required for the vehicle to follow the second target trajectory.

3. The vehicle control system according to claim 1 , wherein the priority condition further includes that the deceleration is required for the vehicle to follow the first target trajectory and the deceleration is required for the vehicle to follow the second target trajectory.

4. The vehicle control system according to claim 1 , wherein the priority condition further includes that a first deceleration required for the vehicle to follow the first target trajectory is equal to or higher than a deceleration threshold and a second deceleration required for the vehicle to follow the second target trajectory is lower than the first deceleration.

5. The vehicle control system according to claim 1 , wherein the priority condition further includes that a first lateral acceleration required for the vehicle to follow the first target trajectory is equal to or higher than a lateral acceleration threshold and a second lateral acceleration required for the vehicle to follow the second target trajectory is lower than the first lateral acceleration.

6. The vehicle control system according to claim 1 , wherein in the vehicle travel control, the at least one processor calculates a required control amount of at least one of the steering, the acceleration, and the deceleration required for the vehicle to follow the target trajectory, and controls the at least one of the steering, the acceleration, and the deceleration in accordance with the required control amount,

a first required control amount is the required control amount required for the vehicle to follow the first target trajectory,

a second required control amount is the required control amount required for the vehicle to follow the second target trajectory, and

the at least one processor further compares the first required control amount and the second required control amount to determine whether or not the priority condition is satisfied.

7. The vehicle control system according to claim 1 , wherein in the vehicle travel control, the at least one processor calculates a required control amount of at least one of the steering, the acceleration, and the deceleration required for the vehicle to follow the target trajectory, and controls the at least one of the steering, the acceleration, and the deceleration in accordance with the required control amount,

a first required control amount is the required control amount required for the vehicle to follow the first target trajectory,

a second required control amount is the required control amount required for the vehicle to follow the second target trajectory, and

the priority condition further includes that the second required control amount is greater than the first required control amount.

8. The vehicle control system according to claim 1 , wherein in the vehicle travel control, the at least one processor calculates a required control amount of at least one of the steering, the acceleration, and the deceleration required for the vehicle to follow the target trajectory, and controls the at least one of the steering, the acceleration, and the deceleration in accordance with the required control amount,

a first required control amount is the required control amount required for the vehicle to follow the first target trajectory,

a second required control amount is the required control amount required for the vehicle to follow the second target trajectory, and

the priority condition further includes that the second required control amount is less than the first required control amount.

9. The vehicle control system according to claim 1 , wherein the travel assist control includes collision avoidance control that assists avoidance of a collision between the vehicle and a surrounding object,

the at least one processor determines whether or not the activation condition of the collision avoidance control is satisfied based on driving environment information indicating a driving environment for the vehicle,

when the activation condition is satisfied, the at least one processor predicts severity of damage due to the collision based on the driving environment information, and

the priority condition further includes that the severity is equal to or greater than a threshold.

10. The vehicle control system according to claim 1 , wherein when the priority condition is satisfied, the at least one processor executes the vehicle travel control by using the second target trajectory as the target trajectory.

11. The vehicle control system according to claim 1 , further comprising a memory device, wherein

the at least one processor stores log information in the memory device, and

the log information includes at least a position where the at least one processor executes the vehicle travel control by giving more weight to the second target trajectory than to the first target trajectory.

12. A vehicle control system that controls a vehicle performing automated driving, the vehicle control system comprising at least one processor configured to:

execute vehicle travel control that controls steering, acceleration, and deceleration of the vehicle such that the vehicle follows a target trajectory;

generate a first target trajectory as the target trajectory for the automated driving of the vehicle;

determine whether or not an activation condition of travel assist control is satisfied, wherein the travel assist control controls at least one of the steering, the acceleration, and the deceleration for at least one of improving safety or comfort of travel of the vehicle, reducing discomfort of an occupant of the vehicle, and stabilizing behavior of the vehicle;

when the activation condition is satisfied, generate a second target trajectory as the target trajectory for the travel assist control;

acquire first reliability information indicating reliability of the automated driving and second reliability information indicating reliability of the travel assist control;

when the second target trajectory is generated during the automated driving, determine whether a priority condition for giving priority to the second target trajectory is satisfied; and

when the second target trajectory is generated during the automated driving and the priority condition is satisfied:

combine the first target trajectory and the second target trajectory to generate a control target trajectory, the combination giving more weight to the second target trajectory than to the first target trajectory, and

execute the vehicle travel control according to the control target trajectory,

wherein the priority condition includes that the reliability of the travel assist control is higher than the reliability of the automated driving.

13. A vehicle control system that controls a vehicle performing automated driving, the vehicle control system comprising at least one processor configured to:

calculate a required control amount for at least one of steering, acceleration, and deceleration for the vehicle to follow a target trajectory;

execute vehicle travel control that controls the at least one of the steering, the acceleration, and the deceleration in accordance with the required control amount such that the vehicle follows the target trajectory;

generate a first target trajectory as the target trajectory for the automated driving of the vehicle, a first required control amount being the control amount required for the vehicle to follow the first target trajectory;

determine whether or not an activation condition of travel assist control is satisfied, wherein the travel assist control controls at least one of the steering, the acceleration, and the deceleration for at least one of improving safety or comfort of travel of the vehicle, reducing discomfort of an occupant of the vehicle, and stabilizing behavior of the vehicle;

when the activation condition is satisfied, generate a second target trajectory as the target trajectory for the travel assist control, a second required control amount being the control amount required for the vehicle to follow the second target trajectory; and

when the second target trajectory is generated during the automated driving:

calculate the required control amount for the vehicle travel control at least in part by combining the first required control amount according to a first weight and the second required control amount according to a second weight greater than the first weight, and

execute the vehicle travel control according to the required control amount.