Abstract
This paper describes effects of variable gear-ratio characteristics of the cable type EPS on vehicle yaw rate gain characteristics. At first, static gear-ratio characteristics according to torsional rigidity of cable are analyzed. Next, influences of the characteristics on a vehicle yaw rate response are examined in order to clarified an appropriate value of the cable rigidity. Finally, yaw rate gain of a vehicle installed on the cable type EPS which has the appropriate rigidity are calculated. As a result, it is theoretically confirmed that the variable gear-ratio characteristics of the cable type EPS according to vehicle velocity and steering wheel angle improve vehicle yaw rate gain characteristics based on vehicle velocity and lateral acceleration.
