Pittsburgh, Pennsylvania - Bayer MaterialScience llc and O-Flex Group Inc. have tackled new pedestrian safety legislations by developing bumper systems using polyurethane foam as the absorber. The tubular components collapse on impact - again and again - without permanent damage.The bumpers, which are currently being used commercially on the Cadillac STS, use Bayer's Bayfill EA foam, and are a lightweight, solution for energy displacement/absorption and pedestrian protection, according to Doug Stratton, project leader, Future Business Automotive Industry Innovation at BMS. "These bumper assemblies are ahead of the curve and meet NHSTA (National Highway Traffic Safety Administration) and IIHS (Insurance Institute for Highway Safety) crash test ratings per vehicle type," he said, in a BMS 5 Sept statement.The quadrangular cross-section tubes, which are made of spin-formed metal, and composite-bonded, have tight, corrugated walls. BMS said in the statement that they can withstand a series of multiple impacts with virtually no degradation in force level or energy absorption efficiency.According to Dr Paul Glance, application engineer for O-Flex, the bumpers show "extremely small permanent set after each impact. ... The metal construction produces a consistent square-wave force level at high and low temperatures. Furthermore, it is unaffected by humidity and aging, which sometimes degrades plastic energy absorbers," he said."We found that the special ultra-low-density Bayfill foam enhances the multiple impact capability of the new bumper prototype," said Glance. "We never really considered any other material," he added."