Recently, Steer-by-wire(SBW), a next-generation steering system in which there is no mechanical link between the vehicle's steering wheel and the front-wheel steering actuator, has been paid more attention by researchers. SBW can control front wheel angle independently of steering wheel angle. Generally, driver is driving with steering angle at low speed region and torque at high speed region. However, this fact has not been proven with theory of vehicle dynamics. Clarification of the steering input on the basis of vehicle dynamics leads to a precise control of SBW. Direct Drive (DD) motor is used to generate artificial steering reaction torque depending on vehicle speed and dynamics on driving simulator. Experimental investigation on driver-vehicle system performance against crosswind disturbance is conducted at high speed with variable steering reaction torque.
