Investigation and Analysis of Real-Life Pedestrian Collisions

Pedestrian collisions are primarily a disease of urban streets and intersections, where both pedestrian and automobile traffic are in high volume. City engineers and planners are plagued with the problem of mitigating the number of pedestrian/vehicle collisions while maintaining traffic flow. In an attempt to study the problem in depth, city engineers in Helsinki, Finland placed a camera in a bus station clock tower overlooking a busy downtown intersection in February of 1991. The camera was placed at the intersection to study pedestrian and vehicle behavior at the intersection and to quantify the speeds of the respective parties. Since its installation, the camera has witnessed fifteen pedestrian/vehicle accidents.

Detailed measurements of the intersection were taken for analysis of the accidents. The intersection was also calibrated with the camera in place for use of the digitizing system. The videotape footage was analyzed using digitizing motion analysis software to quantify the pre-impact and post-impact trajectories of both the vehicle and the pedestrian for each accident. The data were then compared with existing crash test information regarding the trajectory of cadavers and dummies. A comparison to many of the existing pedestrian throw equations was also performed as part of this study.