Patent ID: 8433478

Claim:
A rear wheel steering control device comprising an actuator configured to change a steering angle of a rear wheel installed in a vehicle and a control unit configured to control driving the actuator, capable of changing a steering angle of the rear wheel, wherein: the control unit comprises: an actuator control unit configured to control the actuator; a steering angle command value calculating unit configured to calculate a steering angle command value of the rear wheel on the basis of at least a turning state quantity of a front wheel; a target value setting updating unit configured to perform a target value updating control by setting a steering angle target value of the rear wheel inputted into the actuator control unit in response to the value of the steering command value of the rear wheel inputted from the steering angle command calculating unit; and a command value increase and decrease direction determining unit configured to determine an increase and decrease direction of the calculated steering angle command of the rear wheel, wherein the target value setting updating unit calculates a difference between the steering angle command value of the rear wheel and the steering angle target value of the rear wheel last set as well as limits the calculated target value change quantity to be equal to or lower than a predetermined maximum value and is added to the steering angle target value of the rear wheel last set as a new steering angle target value of the rear wheels; and when the command value increase and decrease direction determining unit detects that the increase and decrease direction of the steering angle command value of the rear wheel changes, the command value increase and decrease direction determining unit sets the target value change quantity in a direction opposite to the action of the actuator and to a predetermined maximum value to have a maximum speed, which is added to the steering angle target value of the rear wheel last set to conduct a target value updating control.