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Hyperelastic material simulations are commonly performed in commercial FE codes due to availability of sophisticated algorithms facilitating virtual characterization of such materials in FEA easily. However, the solution time required is longer in FEA. Especially when excitation frequencies do not interfere with structural modes, flexible multibody simulation offers a lucrative and computationally inexpensive alternative. However, it is difficult to directly characterize hyperelastic materials in commercial MBS simulation codes, so the reduced solution time comes at the cost of decreased simulation accuracy, especially if the designer is provided with crude stress - strain test data. Hence, the need is to overcome the drawbacks in FEA and multibody codes, as well as to leverage best of both these codes simultaneously.

Designers and analysts need to compare and conduct synthesis for selection of materials based on their properties involving simulation, optimization and correlation with test data. An example is that of acoustic material properties such as random and normal incidence sound absorption coefficient and sound transmission loss. The international test standards necessitate having standard operating procedures for characterization of these materials. This procedure is quite involved and addresses steps including test data acquisition, post processing, calculations, classification, report generation and most importantly, storage of such innumerable material properties in a structured manner to facilitate ease of retrieval and updating of properties. It is also highly desirable to have a synergy of the databank directly with simulation tools. Further, all of these steps need to be accurate, non-speculative and quick.

Multidisciplinary analysis that involves simulation of automotive models by carrying out multibody dynamics analysis for load extraction and then followed by inertial relief static analysis for prediction of structural results is commonly followed. Commercial Finite Element (FE) codes require that body loads coming from the multibody analysis be ignored when running the inertia relief analysis, which generates its own internal D'Alembert body loads. In such case, there is, however, a potential pitfall that although the equilibrium is established in the ensuing inertial relief static analysis, the internal body loads do not represent those from the multibody dynamics. This has the potential to produce incorrect results, especially when rotational body loads are very high. The author hereby proposes a methodology to overcome this pitfall to model the exact physics and get accurate results thereof.