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McDonnell Douglas has radically changed its approach to new product development under an internal project called Design, Manufacturing and Producibility Simulation (DMAPS). The new process has four steps: concept baseline, concept layout, assembly layout and build-to-package; each of which relies on three dimensional master solid models and a variety of advanced simulation and modeling tools. The result is a disciplined process that eliminates non-value added activity and provides all Integrated Product and Process Team (IP2T) members with the tools needed to effectively perform assigned tasks. McDonnell Douglas applied the new approach to a redesign of the T-45A Horizontal Stabilator. This project demonstrated that three dimensional master modeling can eliminate two dimensional drawings and enable physical mockups to be replaced by computergenerated virtual prototypes.

Long glass fiber reinforced (LGFR) composites have been widely used in automotive industry to reduce vehicle weight and maintain relatively high mechanical performances. Due to the injection molding process, the distribution of fiber orientations varies at different locations and through the panel thickness, resulting in anisotropic and non-uniform mechanical properties. The current practice of computer modeling of these materials is generally using isotropic properties adjusted by a certain scale factor. The effect of fiber orientation is not carefully considered due to the complexity of fiber orientation distribution in the LGFR parts. The purpose of this paper is to identify key factors affecting vehicle attribute performances where LGFR composites are used; and provide an efficient way for accurate CAE modeling of LGFR composites. In this study, tensile coupons cut from a simple geometric injection molded plaque are tested.

A CAE simulation methodology was developed to predict the warpage and shape deviation from nominal in finished plastic sub-assemblies that are joined using Infra-Red (IR), hot-plate or vibration welding processes. An automotive glove box bin and door sub-assembly was used to develop the methodology. It was seen that part warpage from injection molding and welding causes warpage in final assembled product which results in gaps and the consequent loss in quality of appearance. The CAE simulation methodology included prediction of the part warpage with residual stress from the injection molding process, use the post-molded shape as an initial part condition for the welding process, and simulation of the welding process itself.