The Influence of a Booster Seat on the Motion of the Reclined Small Female Anthropomorphic Test Device in Low-Acceleration Far-Side Lateral Oblique Impacts

Abstract

Belt-positioning booster (BPB) seats may prevent submarining in reclined child occupants in frontal impacts[1, 2]. BPB-seated child volunteers showed reduced lateral displacement in reclined seating in low-acceleration lateral-oblique impacts [1]. As submarining was particularly evident in reclined small adult female occupants [3], we examined if a booster seat could provide similar effects on the kinematics of the small female occupant to the ones found on the reclined child volunteers in low-acceleration lateral oblique impacts. The THOR-AV- was seated on a vehicle seat on a sled simulating a lateral-oblique impact (80° from frontal, maximum acceleration ~2 g, duration ~170 ms). Lateral and forward head and trunk displacements, trunk rotation, knee-head distance, seatbelt loads, head acceleration were recorded. Three seatback angles (25°, 45°, 60°) and two booster conditions were examined. Lateral peak head and trunk displacements decreased in more severe reclined seatback angles (25-36 mm decrease compared to nominal). Forward peak head, trunk displacements, and knee-head distance were greater with the seatback reclined and no BPB. Knee-head distance increased in the severe reclined angle also with the booster seat (>40 mm compared to nominal) . Seat belt peak loads increased with increased recline angle with the booster, but not without the booster seat. Booster-like solutions may be beneficial for reclined small female adult occupants to reduce head and trunk displacements in lateral-oblique impacts, knee-head distance, and motion variability in the severe reclined seatback angle.