Krishnakanth E. Aekbote

A NEW COMPONENT TEST METHODOLOGY CONCEPT FOR SIDE IMPACT SIMULATION

A new component test methodology concept for simulating National Highway Traffic Safety Administration (NHTSA) side impact is described in this paper. The methodology would be used to evaluate the performance of door sub-systems, trim panels and possible safety countermeasures (foam padding, side airbags, etc.). MADYMO software was used to develop the concept and the model was validated with a DOT-SID dummy. The method can also be used for simulating the European procedure, with some modifications. The method uses a combination of HYGE and VIA decelerator to achieve the desired door velocity profile from onset of crash event until door-dummy separation, and also takes into account the various other factors such as the door/B pillar-dummy contact velocity, door compliance, shape of intruding side structure, seat-to-door interaction and initial door-dummy distance.

THE BIOMECHANICAL ASPECTS OF PEDESTRIAN PROTECTION

In this paper, a biomechanical basis for pedestrian protection is presented based on reviews of epidemiological and biomechanical studies conducted over the last three decades. Epidemiological studies reveal the nature and cause of pedestrian crashes and injuries sustained in the field. The various factors that influence pedestrian crashes and fatalities such as pedestrian demographics, time and location of crash, type of vehicles involved and their design characteristics, impact speeds, and nature and severity of injuries sustained are covered in the epidemiology section. The biomechanical studies identify the injury mechanisms and the biomechanical tolerances. Several biomechanical studies that attempt to identify the injury mechanisms and quantify the tolerances are critically reviewed in this paper, and the existing gaps in literature are identified. Further, the three primary injury mechanisms for pedestrian lower extremity injuries are highlighted, and an injury mechanism for depressed tibial fracture is hypothesised. The effect of exterior vehicle parameters such as bumper height, bumper stiffness, hood length, hood stiffness, bumper lead angle on the nature and severity of injuries sustained are also discussed. The biomechanical injury criteria and tolerance values in a proposed draft ECE pedestrian regulation are also presented. Finally, conclusions are drawn based on the epidemiological and biomechanical studies, which lead to a proposal for future work.