Parametric analysis of the effect of CRS seatback angle in dummy measurements in frontal impacts

M. Valdano, J.M. Asensio-Gil, J.R. Jiménez-Octavio, M. Cabello-Reyes, R. Vasserot-Tolmos, F.J. López-Valdés

International Research Council on Biomechanics of Injury - IRCOBI Europe 2022, Porto (Portugal). 14-16 September 2022

Summary:

The  objective  of  this  study  was  to  assess  the  effect  of  modifying  the  seatback  angle  of  a  Child Restraint System (CRS) in the dummy readings and in the associated injury criteria in frontal impacts, performed according  to  the  specifications  of  the  regulation  UN  R129.  A  multibody  model  of a CRS was developed  an validated using the experimental results obtained in a frontal impact of a commercial rear‐facing infant seat (45‐86 cm) using the Q1.5 dummy. Then, the seatback angle of the CRS was virtually modified in the multibody model of the CRS between +10 degrees (more vertical) and ‐10 degrees (more horizontal) at 2.5 degrees intervals. The average CORA rating resulted on a fair score (0.611 average rating) of the dummy readings. The modification of the seatback angle showed that there is a trade‐off between the forces and moments acting on the cervical and the lumbar areas of the spine. Although a more vertical configuration resulted in an improvement of the of criteria specified by the regulations (average 15% reduction using +10 degrees), spine loads resulted on values three times higher than the reference configuration. Further research is needed to assess if the lumbar spine loads may reach injurious levels for these reclined postures.

Spanish layman's summary:

El objetivo de este estudio fue evaluar el efecto de la modificación del ángulo del respaldo (±10°) de un Sistema de Retención Infantil (SRI) orientado hacia atrás en las lecturas de un Q1.5 dummy y en los criterios de lesión asociados en impactos frontales realizados según las especificaciones del reglamento UN R129.

English layman's summary:

The objective of this study was to assess the effect of modifying the seatback angle (±10°) of a rear-facing Child Restraint System (CRS) in the readings of a Q1.5 dummy and in the associated injury criteria in frontal impacts performed according to the specifications of the regulation UN R129.

Keywords: Child restraint system, CRS, multibody model, neck injuries, spine injuries

Published in IRCOBI Conference Proceedings, vol: 22, pp: 519-531, ISSN: 2235-3151

Publication date: 2022-09-16.

Citation:
M. Valdano, J.M. Asensio-Gil, J.R. Jiménez-Octavio, M. Cabello-Reyes, R. Vasserot-Tolmos, F.J. López-Valdés, Parametric analysis of the effect of CRS seatback angle in dummy measurements in frontal impacts, International Research Council on Biomechanics of Injury - IRCOBI Europe 2022, Porto (Portugal). 14-16 September 2022. In: IRCOBI Conference Proceedings, vol. 22, ISSN: 2235-3151