Numerical Simulation in the Design Process of Foam Seats for the Automotive Industry

In the development of foam seats, there are many design variables and design requirements to be taken into account. In this context, numerical simulation can be a valuable tool to facilitate this process and shorten its duration by minimizing the number of test specimens built and the number of real tests made. In general, the aim is to predict the response of a seat under certain conditions and optimize its design with respect to static and dynamic comfort, both from the geometric and material points of view. The work presented in this paper is the result of a preliminary feasibility study carried out within the context of a more ambitious program. This program is aimed to virtually evaluate seat cushion comfort by integrating geometric design, material databases and mechanical simulations under the same working environment. This study is focused on the assessment of the application of numerical simulations done with ABAQUS in the development of car seat cushions made of polyurethane foam. First, mechanical simulations of simple tests were carried out using a hyperelastic constitutive model of ABAQUS in order to adjust its parameters with real test data. Then, a static indentation test, which reproduces the mechanical response of a seat under the load of a dummy occupant, was simulated. The indentation curve was validated with real test results in a first approach. Validation of the contact pressure field is still to be done.