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The role of CAB is protecting the passenger's head during rollover and side crash accidents. However, the performance of HIC and ejection mitigation has trade-off relation, so analytical method to satisfy the HIC and ejection mitigation performance are required. In this study, 3 types of CAB were used for ejection mitigation analysis, drop tower analysis and SINCAP MDB analysis. Impactor which has 18kg mass is impacting the CAB as 20KPH velocity at six impact positions for ejection mitigation analysis. In drop tower analysis, impactor which has 9kg mass is impacting the CAB as 17.7KPH velocity. Acceleration value was derived by drop tower analysis and the tendency of HIC was estimated. Motion data of a vehicle structure was inserted to substructure model and the SID-IIS 5%ile female dummy was used for SINCAP MDB analysis. As a result, HIC and acceleration values were derived by MDB analysis.

In current inflatable curtain airbag development process, the curtain airbag performance is developed sequentially for the airbag coverage, FMVSS 226, FMVSS 214 and NCAP. Because the FMVSS 226 for the ejection mitigation and the NCAP side impact test require the opposite characteristics in terms of the dynamic stiffness of the inflatable curtain airbag, the sequential development process cannot avoid the iteration for dynamic stiffness optimization. Airbag internal pressure characteristics are can be used to evaluate the airbag performance in early stage of the development process, but they cannot predict dynamic energy absorption capability. In order to meet the opposite requirements for both FMVSS 226 and NCAP side impact test, a test and CAE simulation method for the inflatable curtain airbag was developed.

In recent years, products that make use of integrated safety that use the environmental data to optimize occupant restraints have been on the market. Pre-safe system in the integrated safety category is an adaptive and smart protection system that utilizes the occupant information and the monitoring information on the accident prediction. These pre-safe systems need the proper algorithm corresponding to the crash scenario for the crash unavoidable state. Due to the crash scenario categories for the real world accidents is quite various, the development of the algorithm and the occupant protection system to reduce the injury is quite complex and costly. For this reason, a development process for pre-safe related integrated safety systems demands new tools based on the biomechanics to help design and assessment. The virtual development and assessment process with a viewpoint on the efficiency of the restraint development has been developed.

In this study, an integrated process was constructed to perform DOE analysis and find out effects of factors related to the driver airbag shape in NCAP frontal crash. A finite element driver airbag was modeled using BAGGEN, one of the MADYMO ver.5.4.1 utilities. The airbag modeling process was integrated with a driver NCAP frontal occupant crash model. An additional translation process was also integrated to the processes for the XML-based crash model that was modeled using MADYMO ver.6.1. iSIGHT was employed to the whole integration process parsing and the entire processes from driver airbag modeling to Design of Experiment (DOE) were performed automatically exchanging files between MADYMO server and iSIGHT server. From DOE analyses, improved results were achieved compared to the base design specification and factors that dominantly affect passive safety performance were found out.

The integrated correlation methodology is applied to the correlation of the airbag body block test and the component tests of sub systems consisting of the steering control system. By using the optimization technique for the occupant simulation model involving two-dimensional curves as the input, the optimal scale factors of the input F-D curves are found in order to minimize the sum of deviations between simulation and test results. In addition, the optimal one-dimensional unknown inputs that can't be obtained by component tests are found. It is found that the optimization technique used in this study is very suitable for the correlation of the occupant simulation model that has 2-dimensional test input data, and it is able to shorten the entire correlation time and ensure the reliability of the correlation result. This correlation methodology can be applied to the sled test and the barrier test for validating the occupant analysis model.