Responses of Rear Seat ATDs in Frontal Impact Sled Tests: Evaluation of Two Seat Belt Configurations 2017-01-1474

Sled tests simulating full-frontal rigid barrier impact were conducted using the Hybrid III 5^th female and the 50^th male anthropomorphic test devices (ATDs). The ATDs were positioned in the outboard rear seat of a generic small car environment. Two belt configurations were used: 1) a standard belt with no load limiter or pre-tensioner and 2) a seatbelt with a 4.5 kN load-limiting retractor with a stop function and a retractor pre-tensioner (LL-PT). In the current study, the LL-PT belt system reduced the peak responses of both ATDs. Probabilities of serious-to-fatal injuries (AIS3+), based on the ATDs peak responses, were calculated using the risk curves in NHTSA’s December 2015 Request for Comments (RFC) proposing changes to the United States New Car Assessment Program (US-NCAP). Those probabilities were compared to the injury rates (IRs) observed in the field on point estimate basis. The injuries predicted by the risk curves over-predicted the injury rates in the field irrespective of the occupant size, speed, and restraint type evaluated.