Integrating the assessment of pedestrian safety in vehicles with collision detection and mitigation systems

Abstract

This paper presents an integrated model to assess pedestrian protection of vehicles that are equipped with collision detection and mitigation systems. Traditionally, impact injury risk is assessed at a single speed, whereas actual pedestrian collisions occur at many speeds. Therefore, the test result is used to represent risk across all crashes even though no information about the speeds of actual crashes is used explicitly in the assessment. When the impact speed of a vehicle is likely to be affected by technology that reduces impact speeds, the average risk must be less than for equivalent vehicles without such a system. A model is presented in this paper that takes such effects into account by using information on how the test result varies with impact speed, and the relationship between the test result and injury risk, to calculate average injury risk. If the effect of a collision detection system on impact speeds is known, then the model can assess the reduction in average risk for any given impact test result. The model is also used to adjust Euro NCAP and GTR assessment criteria for pedestrian head impact protection when vehicles are equipped with effective pedestrian collision avoidance technologies.