Biomechanical Assessment of Standard and Force-limiting, Pretensioned Belt Restraints in the Rear Seat

摘要

This study investigates the potential benefits and trade-offs of seat belt pretensioners and force-limiters in the rear seat in frontal impact sled tests at two speeds (48 km/h and 29 km/h ΔV) Four different dummies were tested: the Hybrid III six year old (in a booster seat, H3 6Y0), the Hybrid III 5th percentile female (H3 AF05), the Hybrid HI 50th percentile male (H3 AM50), and the THOR-NT. The restraint was either a standard three point belt, or a 3-point belt with a retractor pretensioner and a progressive force-limiter (FL+PT). The FL+PT restraints resulted in a significant (p≤0.05) decrease in peak internal chest deflection for each of the Hybrid III dummies at both test speeds and a non-significant (p=0 06) reduction for the THOR Furthermore, the FL+PT system allowed little or no increase in forward head excursion, and improved whole-body kinematics for all dummies by restricting pelvic excursion and slightly increasing torso pitch.