Physical testing, especially with the modified test configuration, provided good data for correlating the observed markings on the plastic D-rings to accident belt loads and delta-V's. It was demonstrated that delta-V's around 15 mph would result in visible marks on the D-ring for collisions involving 5th percentile females, and delta V's less than 10 mph with 50th percentile male occupants would leave markings. This research also disputed the claim that distinct, visible markings could be left on the D-ring by 'normal' usage of the belt restraint system. The belt loads necessary to leave marks and the corresponding delta-V's were higher than loading that would result from 'normal' usage. This paper documents experimental research determining the belt forces required to create visible and distinct markings on plastic automobile D-rings. The 'D-Ring' is the loop through which the shoulder belt feeds before reaching the retractor. In the experimental configuration, ballast is attached to the belt webbing and dropped from a predetermined elevation. By varying the drop height the belt loading characteristics were also changed. Photographs document the resulting loading marks. A Mathematical Dynamic Modeler was used to calculate the Rigid Body Dynamic models to determine occupant belt loads from 5th and 50th percentile Hybrid III anthropomorphic test devices under various crash pulse conditions. These values were correlated to the experimental research. Conclusions are made relating D-ring markings to the delta-V of an automotive accident.
An experimental examination of seatbelt webbing loading marks on automobile plastic D-rings
Eine experimentelle Untersuchung der Sitzgurt-Web-Zuführmarkierungen auf die Plastik-D-Ringe beim Einsatz im Fahrzeug
2004
5 Seiten, 14 Bilder, 5 Tabellen, 2 Quellen
Conference paper
English