Method of Selecting Test Scenarios for Pedestrian Forward Looking Pre-Collision System Evaluation 2014-01-0163

While the number of traffic fatalities as a whole continues to decline steadily over time, the number of pedestrian fatalities continues to rise (up 8% since 2009) and comprises a larger fraction of these fatalities. In 2011 there were 4,432 pedestrians killed and an estimated 69,000 pedestrian injuries [1]. A new generation of Pedestrian Pre-Collision Systems (PCS) is being introduced by car manufactures to mitigate pedestrian injuries and fatalities. In order to evaluate the performance of pedestrian PCS, The Transportation Active Safety Institute (TASI) at Indiana University-Purdue University Indianapolis is developing a set of test scenarios and procedures for evaluating the performance of pedestrian PCS with the support of the Collaborative Safety Research Center of Toyota. Pedestrian crashes are complex in that there are many aspects about location, driver behavior, and pedestrian behaviors that may have implications for the performance of the PCS. This complexity will generate far more scenarios than can be reasonably tested. This paper describes a test scenario selection process that uses not only the percentage importance of crash scenarios in terms of combinations of variables, but also ensures that individual variables are adequately represented in the chosen tests. The total number of test scenarios can be specified based on the percentage representation coverage according to the crash data or by the testing agency. The advantage of this method is that both important scenarios and important scenario variable values are guaranteed to be included in the set of test scenarios. The proposed method is demonstrated using GES and FARS pedestrian crash data for 2010 and 2011. The crash scenarios are described with variables that can be used for setting up vehicle tests, such as the pedestrian sizes, light conditions, pedestrian motion directions, pedestrian motion behavior/speeds, vehicle motion directions, and vehicle motion speeds. This method can also be used for creating a parsimonious set of test scenarios for other vehicle active safety features.