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The functional performance of the instrument panel has been changing dramatically since the late 80s, with FMVSS 208 legislation and its related impact on the addition of air bags and knee bolsters. In addition to addressing occupant safety legislation through more safety components, as well as navigation, security, comfort, informational and other systems are being added to the instrument panel as the consumers' desire for enhanced features continues. At the same time, consumers still want a product that is uncomplicated, affordable, aesthetically pleasing and - at the same time - doesn't limit valuable interior compartment space. The early efficient integration of these components (electrical, architecture, HVAC, steering) in the design, engineering and assembly process will be the areas of requirement that will have a primary effect on IP system cost in the future.

The blow molded knee bolsters on the 1996 Chevrolet Astro and GMC Safari vans are the first blow molded parts used on an interior structural application. These knee bolsters also meet FMVSS 208 requirements. The one-piece bolsters, used on both the driver's and passenger's sides of the vehicle reduced cost by $4.00 and weight by 40% per vehicle compared with two-piece, steel-reinforced plastic knee bolsters. Additional savings were realized in tooling cost reductions of $300,000 and a development time that was shortened by 64 weeks. Part testing was also reduced to the tunability of the process. Aesthetic concerns of matching adjacent injection molded and vinyl parts were also met. This paper discusses the combination of material, processing and tooling technologies that made this program a success.

The first fully integrated structural instrument panel significantly reduces the cost, weight and part count of a conventional instrument panel. The structural design consists of a cross-car beam/duct, retainer, and knee bolsters. Part integration and consolidation, use of ductile engineering thermoplastics, and the total system design are all contributors to the success of reducing cost and weight. A cost savings of $1.3 million in tooling and $500,000 in manufacturing were achieved with a weight savings of 6.0 pounds per vehicle. The new instrument panel design effectively meets the requirements of Federal Legislation for occupant protection (FMVSS 208). All parts are molded from the same ductile engineering thermoplastic, which enhances the potential for economical disassembly and recycling. The fully integrated structural instrument panel system was developed for the 1994 Buick Roadmaster Platform, as shown in Figure 1.

The development of impact and heat distortion data for plastic instrument panel supports will be discussed using panels molded of glass fiber reinforced styrene and styrene-acrylonitrile materials. Two typical design configurations will be analyzed with special emphasis being given to glass fiber content and part thickness. Such information is valuable in the design and material selection of plastic instrument panel supports, primarily those parts with large unsupported areas. The glass fiber reinforced styrene-acrylonitrile materials exhibit higher impact performance and improved heat distortion performance over styrene materials.