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Automobile manufacturers, designers, and cockpit system integrators are in constant search of solutions that reduce the number of interruptions across interior surfaces. Engineers require that this solution be efficient in terms of reliability, parts complexity, packaging space, and cost. The purpose of this paper is to describe the design and development of a cost effective, simplified seamless passenger airbag door system with an integrated chute for instrument panels. Through engineering thermoplastic material property advantages and scoring designs, this solution has a construction which may meet both styling and performance criteria while eliminating component parts such as a separate airbag chute, hinges, tethers, brackets, inserts, fabrics, and fasteners.

This paper describes a methodology to prototype and validate thermoplastic energy absorbers in a broad range of vehicle geometries. The objective of this prototype tool designed with quick prototype methodology is to achieve ready PC/PBT energy absorber designs for pedestrian testing. Generic vehicle models were used to finalize the energy absorber design features. The prototype tool was designed from optimized energy absorber designs that meet pedestrian performance in low packaging space, typically 45–60 mm. A set of prototype tools is being built to match different beam heights and packaging spaces. The tool has also the functionality of achieving different thickness and different design features using the latest manufacturing technologies. A full energy absorber can be built from individual lobes over the width of the car. The finalized design combined with ‘quick prototyping’ methodology was used to finalize the mold design, which can cater to a wide range of vehicle geometries.

A model has been developed and implemented at GE Plastics that predicts a material's color shift when weathered. The material's color shift is due to the summation of color shifts from each individual component. By individually measuring the change in each component's optical coefficients upon weathering and using a multiple light scattering model, one can predict the color shift of a material composed of mixtures of these components. The model has been shown to have a standard deviation of 0.4 to 0.9 when predicting color shifts E*, for PC-polyester copolymers, ABS, and ABS/PC blends using an automotive exterior test, SAE J1885, ASTM D 4674, and ASTM D 4459.

Current accelerated weathering protocols such as SAE J1960 or ASTM G26 do not provide reliable, predictive results for engineering thermoplastics. Correlation factors among resin types and even different colors of a single resin have variations that are 60-100% of the mean at the 95% confidence level, making these tests useless for lifetime prediction or even reliable ranking of materials. We have developed improved conditions using CIRA/sodalime-filtered xenon arc, a more rain-like water spray, and occasional sponge-wiping of the samples. The data for gloss loss and color shift agree very well with Florida data giving a correlation factor of 3100±680 kJ/m2 (at 340 nm) per Florida year at the 95% confidence level. The acceleration factor is 7.6x.