Patent attributes
The present disclosure relates to a rear-wheel steering system and a controlling method thereof. The rear-wheel steering system includes: a rack configured to transmit a driving force generated from a rear-wheel steering motor to rear wheels; a first correction module configured to, when an engine is started, detect a position of the rack using a displacement sensor and calculate a first correction value that is a difference between the detected position and a neutral position; a second correction module configured to, when the engine is started, detect a position of the rack using a motor position sensor that detects a rotation angle of the rear-wheel steering motor and calculate a second correction value that is a difference between the detected position and the neutral position; a comparison determiner configured to compare the first correction value and the second correction value to determine whether the displacement sensor has malfunctioned; and a steering controller configured to control an operation of the rear-wheel steering motor. Accordingly, it is possible to determine whether an error occurs in the displacement sensor and to return the rack to the neutral position even when the error has occurred in the displacement sensor.
