Electric power steering system(EPS) is a new power steering technology for vehicle and important device for improving vehicle’s dynamics and static performances. EPS can be divided into the following three forms: the Column assist type EPS(C-EPS), the Pinion assist type EPS(P-EPS), and the Rack assist type EPS(R -EPS). System stiffness of Different types of EPS which effects on steering performance, are known by simulation result and measuring products. P types of EPS are more stiffer than C types of EPS and contribute to steering performance at on centre range of vehicles. By analyzing of performance with types of EPS, this paper proposed improving method for C-EPS stiffness.

Abstract
 1. 서론
 2. 시스템 모델링
  2.1 C-EPS 모델
  2.2 P-EPS 모델
 3. 결과 및 고찰
 4. 결론
 참고문헌

• 유충준(경기대학교 기계시스템공학과) | C. J. You