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The worldwide involvement in global technical regulation (GTR) discussion shows the increasing importance of pedestrian safety as a global concern. In the US, bumper systems are designed for the Part 581 bumper standard and IIHS (Insurance Institute of Highway Safety) bumper structural test protocols. There has also been discussion in the North American automotive industry about the merits of incorporating some measure of pedestrian protection into their systems as well. Compliance with the potential pedestrian leg requirements creates a design conflict with current bumper damageability standards and possibly CAFÉ laws. The difficulties of designing a bumper system that is rigid enough to protect the vehicle in low speed crashes and, at the same time, compliant enough to protect a pedestrian raise questions as to whether these ideas are compatible.

Global warming and climate change are among the top subjects of growing global concern. According to International Energy Agency (IEA), about 19% of the greenhouse gas emissions from fuel combustion are generated by the transportation sector, and its share is likely to grow. A forecast by US Census Bureau predicts that there will be 3.5 billion cars by 2050 for a population of 9 billion. In this context, numbers in the industrialized world are expected to double from around half a billion to over one billion. An increase in fleet volume will have a direct and major impact on increase of CO₂ emissions. Therefore, reducing vehicle fuel consumption is one of the most critical steps for reducing greenhouse gas emissions, and reduction of vehicle weight is one of the best solutions for improving fuel efficiency.

Previous papers by the present authors described use of computational fluid dynamics (CFD) to quantify the effect of glazing thermal conductivity on steady-state heating, ventilation and air-conditioning (HVAC) load under wide-ranging climate and state of motion scenarios, and to estimate the significance of this effect for electric battery performance. The CFD simulations yielded the total heat transfer between the ambient and the cabin of a model car, including radiative and convective heat transfer. The five-fold lower inherent thermal conductivity of polycarbonate relative to glass was found to reduce steady-state HVAC load by several percent in all scenarios, leading to reduced greenhouse gas emission or increased electric range, according to the type of vehicle.

A headlamp reflector has many performance requirements. Principal among these is the need to deliver a compliant beam pattern while withstanding a severe heat environment. In serving this requirement, the reflector must reliably secure the light source (bulb filament) relative to the optical prescription (facets) of the reflector. Traditionally, achieving this performance requirement has been challenging since the reflector elements which are designed to deliver stable and reliable optical performance, are the same elements which must also withstand thermal stresses and adjustment-related static stresses within the reflector. The integrity of these optical elements may also be limited by surface sink, especially in the bulb fastening and attachment locations. The current work describes the design of a reflector bracket through which these forces can be minimized and accommodated while delivering robust optical performance.