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Most airbag systems currently in use rely on crash detection systems containing sensors based on electromechanical technologies to trigger deployment. The majority of these systems contain multiple sensors located in different parts of the vehicle which are capable of identifying significant crashes in a timely manner. Systems based on other technologies such as all-mechanical or electronic sensors have also been employed in a small number of upscale vehicle platforms. Industry emphasis on cost reduction and quality improvement has resulted in a strong interest in alternate sensor technologies. Thus sensors based on new candidate technologies are now under evaluation for use in the near future. A meaningful evaluation of these systems must account for possible tradeoffs including cost, reliability and overall performance. Breed Technologies, Inc. has outlined a comparative evaluation of such systems based on these criteria.

Multi-point sensing for airbag deployment, which is widely used today, incurs costs of wiring and installation and exposes the sensor to the severe under-hood environment. Single-point sensing by a sensor packaged with the airbag can be used to avoid these problems, provided that enough of the crash pulse reaches the sensor to enable an accurate and timely decision about airbag deployment. Most present vehicles do not have appropriate structural characteristics for such sensing, especially in pole crashes and angled barrier crashes. An optimum structure would transmit information about the crash to the sensor and then yield. One component needing modification to achieve this is the bumper. Finite element analysis using DYNA3D is used to explore possible modifications to front structures to permit single-point sensing by a passenger compartment sensor. Such redesign might also improve the shape of the occupant's deceleration history.