Door velocity and occupant distance affect lateral thoracic injury mitigation with side airbag

Abstract

The relationship between thoracic injury risk and parameters of door velocity and occupant distance was delineated in blunt lateral impact with side airbag deployment. A sled impact model was exercised with the validated MADYMO fiftieth percentile facet occupant model and a generalized finite element torso side airbag. Impact velocity was incremented from 4.0 to 9.0 m/s; occupant-airbag distance (at time of airbag activation) was incremented from 2.0 to 24.0 cm; simulations without airbag were also examined. Using compression, deflection rate, and the Viscous Criterion, airbag performance was characterized with respect to occupant injury risk at three points of interest: occupant distance of most protection, distance of greatest injury risk, and the newly defined critical distance. The occupant distance which demonstrated the most airbag protection, i.e., lowest injury risk, increased with increasing impact velocity. Greatest injury risk resulted when the occupant was nearest the airbag regardless of impact velocity. The critical distance was defined as the farthest distance at which airbag deployment exacerbated injury risk. This critical distance only varied considering chest compression, between 3 and 10 cm from the airbag, but did not vary when the Viscous Criterion were evaluated. At impact velocities less than or equal to 6 m/s, the most protective occupant location was within 2 cm of the critical distance at which the airbag became harmful. Therefore, injury mitigation with torso airbag may be more difficult to achieve at lower ΔV.

Finite Element Model Prediction of Pulmonary Contusion in Vehicle-to-Vehicle Simulations of Real-World Crashes

“…In contrast to a CIREN data comparison, the dynamic crush is important to PC injury prediction. In future studies, the dynamic crush and door intrusion rate should be validated for the vehicle model and considered in the prediction in PC (Hallman et al 2011).…”

“…The lung elements were modeled with * MAT ELASTIC FLUID and tetrahedral elements. The element section definition was solid with an element formulation of 13, a one-point nodal pressure tetrahedron (Hallman et al 2011). In the THUMS manual, a pressure threshold for pulmonary contusion was suggested.…”

Lateral Collision with Side Airbag: A Literature Review

“…Computer Aided Engineering (CAE) software are used widely by the designer and researchers as a tool to analyze the product performance at components and systems level, instead of physical prototype testing conventionally. By using CAE software, Madymo, Hallman and his team [23] are able to study relationship between occupant thorax injury risk against impact velocity and occupant distance in side impact with thorax airbag deployment. Hallman et al [23] studies shows that occupant injury risk raised if impact velocity increased.…”

“…By using CAE software, Madymo, Hallman and his team [23] are able to study relationship between occupant thorax injury risk against impact velocity and occupant distance in side impact with thorax airbag deployment. Hallman et al [23] studies shows that occupant injury risk raised if impact velocity increased. Furthermore, highest injury recorded at closest distance between occupant and side airbag regardless of impact velocity.…”