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Passenger protection to reduce fatality and injury rates is of critical importance worldwide. Side and head impact occupant protection requirements have been legislated both in North America and Europe. Even though the applicable legislation for each impact condition is different, the impact event poses similar functional requirements. Therefore, concept designs and methodologies for engineering optimization can be used interchangeably to develop countermeasures whether dealing with side or head impact crashworthy systems. The present paper outlines the use of a systematic approach that combines structural CAE simulations and Design of Experiments (DOE) for the optimization of the structural performance of crushable thermoplastic energy absorbers that are being used in door panels and upper interior trim. The use of DOE allows the evaluation of critical design and material parameters which affect the performance of the system.

The drive for lower weight instrument panels (IP) can be addressed with different design approaches. The first and more traditional approach is to substitute existing substrate materials with materials having a higher stiffness-to-density ratio. The second approach looks at the sub-system level where weight reduction is achieved through part integration. To exemplify this type of designs, examples of innovative knee bolster solutions are shown. The third and most radical approach is weight reduction at the system level. Alternatives to instrument panels that use traditional cross car beam structures will be presented. With these alternatives, hybrid and structural instrument panels can be developed in which weight reduction is achieved by part integration and by allowing plastic materials to fulfill a more significant structural role than in traditional IPs.

Modular front-end carriers to pre-assemble front-end components such as cooling systems, lights, and bumper beam have been in production in different vehicles for several years. Compression molded or overmolded steel/plastic carriers have traditionally been used. The present paper explains the design, material options, and engineering optimization of a composite front-end carrier, which utilizes long glass fiber injection moldable resins and adhesively bonded steel reinforcements. Experimental evaluation of prototypes shows the system met the functional performance requirements at minimum weight.

Fully-integrated structural instrument panels (IP) have been in commercial use in passenger cars, light trucks, and sport utility vehicles for some years now. They offer a cost-effective alternative to the more traditional IP construction that utilizes full-size cross car beams to achieve the structural stiffness and energy management required to meet Federal Motor Vehicle Safety Standard (FMVSS) 208 and corporate performance requirements. The natural evolution of interior designs demands an increasing level of integration of the different components in the interior of the vehicle. Therefore, the natural extension of current structural IP technology is to integrate the steering column subassembly, i.e., steering column and column support, and the heat, ventilation, and air conditioning (HVAC) unit into a modular pre-assembled system.

Structural instrument panels are an excellent alternative to traditional constructions since they can provide substantial part consolidation, weight reduction, tool and cost savings, and manufacturing and assembly simplification. In structural panels, the main energy absorbing element for decelerating an unrestrained occupant is the plastic integrated retainer-structural duct. The role of the components in the instrument panel needs to be clearly understood for adequately engineering the system and properly selecting the polymeric material for optimum system performance in the different operating environments. The present paper discusses the performance of the structural instrument panel, the engineering and design requirements, and provides guidelines for selection of materials.

The increase in instrument panel design and functional performance requirements has resulted in a variety of structural architectures that have been utilized in different passenger vehicles, vans, and light trucks. Each architecture can be designed and engineered to meet corporate and federal requirements using different levels of integration, functionality consolidation, and assembly simplification. The present paper reviews three basic IP design architectures, i.e., traditional, hybrid, and structural, and discusses the performance requirement-functionality matrix in each case. Emphasis is given at explaining the role components play in the different architectures, defining their contribution to static, dynamic and crash performance and their relation to the overall assembly process and sequence. Performance and functionality requirements are linked to basic material characteristics that guide material selection for achieving design targets.

Automotive manufacturers are driving for improvement, creativity and innovation in vehicle systems in order to differentiate products in the global market. Progress in fuel efficiency, occupant safety, comfort, recyclable friendly pre-assembled modular systems, and novel manufacturing methods is difficult to achieve if no major departure from the traditional design, engineering, material mix, and assembly approaches is considered. More importantly, these benefits will not materialize unless the relationship between automotive manufacturers and suppliers changes, allowing suppliers to take a more active role in the vehicle development process. The present paper explores achievements made towards the development of new, innovative technologies to address simplification and overall performance improvements using non-traditional materials.

Since their introduction in automobiles, polymeric materials have enabled designers and engineers to differentiate products based on performance attributes, mechanical response, aesthetics, and manufacturing techniques. A large segment of these applications utilizes polypropylene (PP) resins. One of the attractive features of PP polymers is the ability to tailor their mechanical, thermal and processing performance envelope via modification of their composition and the addition of fillers. Key to the successful application of PP resins in structural systems is the ability of designers and engineers to understand the material response and to properly model the behavior of PP structures upon different mechanical and thermal loading conditions.

Automotive body structures are developed to meet vehicle performance requirements primarily based on ride and handling, crashworthiness, and noise level targets. The body is made of a multitude of sheet metal stampings welded together. Other closures such as fenders, hood, doors and trunk lid are developed to match body interfaces, to contribute and participate in the overall vehicle response, and to meet the sub-system and system structural requirements. In order to improve performance and achieve weight reduction of the overall vehicle steel structure, new polymeric materials and treatment strategies are available to body structural engineers to optimize the response of the vehicle and to tune vehicle performance to meet specified functional requirements. If early integrated to the design cycle, these materials help not only improve the structural body response, but also decrease the weight of the integrated body structure.