Experimental Study of Pedestrian Injury Minimization Through Vehicle Design

The overall objective of this experimental investigation of pedestrian/vehicle impacts was to conduct representative impacts of unembalmed cadavers in order to (1) pioneer the establishment of impact tolerance levels for the pelvis and legs of a standing pedestrian and (2) explore the ability of a few selected geometry and compliance modifications to the impacting vehicle to increase the impact velocities that can be tolerated. A series of 15 experimental impacts were conducted which covered a speed range from 10 to 30 mph. Dynamic data obtained included high-speed films and time histories of (1) bumper and hood edge forces, (2) horizontal and vertical ground reaction forces, and (3) pelvic acceleration. The resulting injuries were determined from examination of pre- and post-impact X-rays and detailed pathological dissections, and were assessed as to probable temporary total and permanent partial disabilities. Three of the key results are that (1) injuries to the lower body of an adult pedestrian are strongly dependent upon vehicle design, (2) the pedestrian leg injury mechanism is a complex dynamic event influenced significantly by both the bumper force and the ground friction force, and (3) a threshold tolerance value of pelvic acceleration appears to exist below which pelvic injuries do not occur.