Abstract: Disclosed is motor driven power steering system of a redundancy structure. The system includes a driving motor that drives a steering wheel, first and second power circuits that supply control power, first and second driving circuits that drive the driving motor, first and second position sensors that detect a rotational position of the driving motor, and first and second processors operatively coupled to the driving motor. The first processor and second processors are operatively coupled to respective redundant elements of the power circuits, the position sensors, and the driving circuits. Each of first processor and the second processor independently receives steering control signals from the upper-level control device to allow the driving circuits to be operated based on the respective position sensors, thereby allowing the driving motor to be operated.

Abstract: An independent steering control apparatus may include: a processor configured to analyze whether wheels are abnormal, on the basis of turning angles of the respective wheels, and revise the turning angles of normal wheels except an abnormal wheel in which a fault occurred, according to the analysis result; and a wheel controller configured to control steering of the wheels according to the turning angles of the wheels, input from the processor.

Abstract: An apparatus including a command front wheel angle acquirer to acquire a command front wheel angle, a four-wheel target angle calculator to calculate a turning radius, which is a distance from a center of rotation when a vehicle is turning to a center of gravity in a Bicycle model, using the model in a state in which a front wheel angle of the model is simulated as the command front wheel angle, to calculate a rotation angle at the center of gravity of the model on the basis of a ratio of rotation angles of front and rear wheels of the vehicle calculated from a state parameter of the vehicle, and to calculate a target angle of each of the four wheels on the basis of the turning radius and the rotation angle, and a controller to independently control steering of the four wheels using the calculated each target angle.

Abstract: An apparatus for controlling rear wheel steering includes a steering angle sensor detecting a steering angle of a steering wheel; a vehicle speed sensor detecting a vehicle speed of a vehicle; a steering torque sensor detecting a steering torque applied to a steering shaft; and a control unit calculating a front wheel angle and a steering angle velocity from the steering angle detected by the steering angle sensor, calculating a rear wheel angle compensation factor for improving rear wheel steering responsiveness based on at least one of the steering torque detected by the steering torque sensor and the calculated steering angle velocity and a same/opposite phase gain depending on the vehicle speed detected by the vehicle speed sensor, and calculating a target rear wheel angle based on the front wheel angle, the rear wheel angle compensation factor and the same/opposite phase gain.

Abstract: A method for controlling rear wheel steering of a vehicle may include: determining, by a control unit, whether an error exists in rear wheel steering control input information received therein to control rear wheel steering of the vehicle; calculating, by the control unit, a rear wheel angle reduction rate for controlling rear wheels to neutral based on a yaw rate of the vehicle when it is determined that an error exists in the rear wheel steering control input information; and controlling, by the control unit, the rear wheels to neutral according to the calculated rear wheel angle reduction rate.

Abstract: An apparatus for controlling rear wheel steering includes a steering angle sensor detecting a steering angle of a steering wheel; a vehicle speed sensor detecting a vehicle speed of a vehicle; a steering torque sensor detecting a steering torque applied to a steering shaft; and a control unit calculating a front wheel angle and a steering angle velocity from the steering angle detected by the steering angle sensor, calculating a rear wheel angle compensation factor for improving rear wheel steering responsiveness based on at least one of the steering torque detected by the steering torque sensor and the calculated steering angle velocity and a same/opposite phase gain depending on the vehicle speed detected by the vehicle speed sensor, and calculating a target rear wheel angle based on the front wheel angle, the rear wheel angle compensation factor and the same/opposite phase gain.

Abstract: A method for controlling rear wheel steering of a vehicle may include: determining, by a control unit, whether an error exists in rear wheel steering control input information received therein to control rear wheel steering of the vehicle; calculating, by the control unit, a rear wheel angle reduction rate for controlling rear wheels to neutral based on a yaw rate of the vehicle when it is determined that an error exists in the rear wheel steering control input information; and controlling, by the control unit, the rear wheels to neutral according to the calculated rear wheel angle reduction rate.