Design of Energy Absorbing Upper Torso Restraint Systems

Based on current DOT requirements for a car occupant restraint in car crashes, the load-extension characteristics for an upper torso belt system capable of safety restraining an average motorist in crashes up to 50 mph when worn snugly are analytically determined. The belt characteristics are shown to depend, among other factors, on the total inherent slack in and the permissible displacement of the belt system. Energy absorption is incorporated into the system by means of a mechanical device activated at a specific magnitude of bell load defined by the initial elastic belt elongation.