보행자 보호와 차량 저속 충돌 성능을 고려한 차량 전면 구조물의 설계

Abstract

Various regulations are related to the automobile frontal structure. They are for pedestrian protection, the FMVSS part 581 bumper test and the RCAR test. In this research, a new bumper system is designed to meet the performance for pedestrian protection as well as FMVSS part 581 bumper test. The details are that a new bumper system is obtained for lower leg impact protection and 8 ㎞/hr pendulum bumper test. There are conflictions in the design requirements. For lower leg protection, a relatively soft bumper system is required while a relatively stiff system is typically needed to sustain the pendulum impacts. An abstract design of a new bumper system is proposed. For detailed design, the system is analyzed by using the nonlinear finite element method. An optimization problem is formulated to incorporate the analysis results. The response surface approximation optimization (RSAO) algorithm is utilized to solve the formulated problem. In addition to the above regulations, the research committee for automobile repairs (RCAR) is considered to reduce the repair cost. The repair cost in a low speed crash could be reduced by using an energy absorbing component such as a crash box. Also, the crash box is analyzed by using the nonlinear finite element method. An optimization problem is formulated and the discrete design using orthogonal arrays (DOA) method is utilized to solve the formulated problem. DOA is utilized for design in the discrete space and the results of the design are discussed.