The primary task of the bumper is to withstand minor impact (e.g. with walls, poles, other vehicles) during parking or car-to-car collisions so as to prevent damage to the car or reduce the cost of repairs. In order to fulfill these requirements, the front bumper needs to be positioned relatively high, its protrusion from the body and its contact area should be large, and, most of all, it must absorb relatively high impact energy. In contrast to this, in order to reduce the severity of injuries to the lower legs of pedestrians and, in particular, to prevent injuries to the knee or ankle, the bumper design should be completely the opposite: i.e., the initial contact point as well as the bumper stiffness should be rather low. The problems resulting from these conflicting requirements are discussed in detail. It appears very difficult to fulfill both requirements - possibly with a system consisting of the conventional bumper and, in addition, a pedestrian friendly bumper positioned approximately 150 mm below and slightly protruding. However, the authors are not convinced that such a complicated and costly double bumper system will be the most efficient solution. Instead of this, measures to prevent any car-to-pedestrian collisions probably would be more suitable. (A) For the covering abstract of the conference, see IRRD 837684.
Abstract