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Multidisciplinary Design Optimization (MDO) of an automobile body structure is a challenging task as it involves multiple, often conflicting requirements of safety, durability & NVH. Conventionally MDO process requires running large number of design of experiments (DOE) to explore the full design space and to build response surface for optimization. As the safety simulations are highly nonlinear in nature, they typically require significant amount of computational time and resources. Hence the conventional MDO approach is too expensive if too many design variables are simultaneously considered. In this paper, an alternative approach using Equivalent Static Load (ESL) method has been suggested for MDO which is quicker & accurate. The basic idea of the Equivalent Static Load-Method (ESL) is to divide the original nonlinear dynamic optimization problem into an iterative linear optimization and nonlinear analysis process.

Crashworthiness enhancement of vehicle structures is a very challenging task during the early design development process. Major factors influencing occupant injury in frontal impact are vehicle front crush space, crash pulse severity, restraint properties and occupant packaging space. This paper establishes a methodology to define suitable criterion that will guide the designers to select the optimal values of the above mentioned parameters during the early phase of the vehicle development. The usage of lumped mass models, pulse characterization techniques were explored to validate the results. Efficient crash energy management, the concepts of ride down and restraint efficiency parameters were also discussed in the paper.

The development of a mobile deformable barrier (MDB) for use as a passenger car surrogate in car-to-LTV impacts is examined here. Since data from crash tests are subject to variations in vehicle properties as well as variations in test configurations, it is likely that repeated identical tests utilizing nominally identical vehicle pairs will yield different results due to these variations. It is necessary to account for the above variations and the resulting response corridor in developing vehicle surrogates if these surrogates are to be used for evaluating compatibility. Results are presented here for the ‘response corridor’ of a medium size passenger car, obtained from finite element simulation of car-to-LTV impacts with defined variations in the input parameters. An MDB concept is then developed to represent this ‘response corridor’ in impacts with LTVs.