Citation

Majstorovic J, Bing J, Dahle E, Bolte JH, Kang YS. Traffic Injury Prev. 2018; 19(Suppl 1): S146-S152.

Affiliation

The Ohio State University, Injury Biomechanics Research Center , Columbus , Ohio.

Copyright

(Copyright © 2018, Informa - Taylor and Francis Group)

DOI

10.1080/15389588.2017.1397643

PMID

29584504

Abstract

OBJECTIVE: Few studies have looked at the effectiveness of the top tether during side impacts. In these studies, limited anthropomorphic test device (ATD) data were collected and/or few side impact scenarios were observed. The goal of this study was to further understand the effects of the top tether on ATD responses and child restraint system (CRS) kinematics during various side impact conditions.

METHODS: A series of high-speed near-side and far-side sled tests were performed using the FMVSS213 side impact sled buck and Q3s ATD. Tests were performed at both 10° and 30° impacts with respect to the pure lateral direction. Two child restraints, CRS A and CRS B, were attached to the bench using flexible lower anchors. Each test scenario was performed with the presence and absence of a top tether. Instrumentation recorded Q3s responses and CRS kinematics, and the identical test scenarios with and without a top tether attachment were compared.

RESULTS: For the far-side lateral (10°) and oblique (30°) impacts, top tether attachment increased resultant head accelerations by 8-38% and head injury criterion (HIC₁₅) values by 20-140%. However, the top tether was effective in reducing lateral head excursion by 5-25%. For near-side impacts, the top tether resulted in less than 10% increases in both resultant head acceleration and HIC₁₅in the lateral impact direction. For near-side oblique impacts, the top tether increased HIC₁₅by 17.3% for CRS A and decreased it by 19.5% for CRS B. However, the injury values determined from both impact conditions were below current injury assessment reference values (IARVs). Additionally, the top tether proved beneficial in preventing forward and lateral CRS rotations.

CONCLUSIONS: The results show that the effects of the top tether on Q3s responses were dependent on impact type, impact angle, and CRS. Tether attachments that increased head accelerations and HIC₁₅values were generally counterbalanced by a reduction in head excursion and CRS rotation compared to nontethered scenarios.

Peer-reviewed paper from the 61st Annual Scientific Conference of the Association for the Advancement of Automotive Medicine (AAAM), October 2017

Language: en

Keywords

LATCH; child restraint system; child safety; side impact; top tether