The automotive industry today faces the challenge of developing a single side impact occupant restraint system to meet performance requirements for multiple crashworthiness test modes. The side air bag, door liner, and vehicle side body structure are key systems that affect the injury criteria of the occupant. This paper discusses how DOE/optimization methods are used to quickly develop a specification for the side air bag and door liner that meets occupant injury criteria for three different side impact test modes. The work detailed in this paper focuses on occupant protection assessment based on three different CAE side impact sled models using ES2-re, DOT-SID and SID-2s, dummy models to evaluate the new FMVSS 214, SINCAP and SICE test modes.

Ten design variables were selected from air bag and door liner parameters which include mass flow rates, vent areas, two variables that define the location of the bag, and material/thickness of the door liner. Occupant injury parameters such as rib deflections/accelerations, pelvis accelerations/forces, and abdomen forces were selected as the responses. As the first step, a latin hypercube DOE method was used to evaluate sensitivity of the design variables to occupant injury parameters. Based on the DOE dominant design variables, optimization criteria and methods were established for the next step. Key injury criteria for each test mode were selected as the constraints. A self adaptive evolution (SAE) global optimization method was used to carry out automated simultaneous simulations. Based on the optimization results eleven feasible design specifications were found. Out of these candidates the optimum design was selected for further evaluation.