Numerical Investigation on Thorax Rib Deflections of 50th Male in Vehicle Side Oblique Pole Impact Using Human Body Model

Key findings from this study

This research indicates that:

• Arm-thorax interaction contributes minimally to excessive upper thoracic rib deflection observed in side oblique pole impacts with the WorldSID-50M dummy.
• Excessive rib deflection during oblique pole testing does not occur in standard side moving deformable barrier tests, indicating distinct loading mechanisms.
• Factors beyond arm-thorax mechanical coupling primarily drive the excessive deflection patterns observed in oblique pole crash scenarios.

Overview

The WorldSID-50M dummy demonstrates superior biofidelity in standardized side crash testing but exhibits excessive upper thoracic rib deflection during side oblique pole impact tests with shoulder-covering airbags. This deflection does not occur in standard side moving deformable barrier tests. The study documents this phenomenon systematically and investigates whether arm-thorax mechanical interaction explains the excessive deflection using a 50th percentile male Human Body Model.

Methods and approach

Numerical simulation using a Human Body Model representative of a 50th percentile male occupant. The analysis compared rib deflection patterns between side oblique pole crash scenarios and standard side moving deformable barrier tests. Simulations isolated and quantified the contribution of arm-thorax interaction to upper thoracic rib deflection.

Results

Numerical simulation revealed that arm-thorax interaction contributes to overall rib deflection in side oblique pole impacts. However, this mechanical interaction accounts for a negligible portion of the excessive upper thoracic rib deflection observed in the WorldSID-50M dummy during oblique pole testing. The deflection pattern differs substantially from that produced in standard side moving deformable barrier tests, suggesting that oblique pole geometry and impact dynamics generate distinct loading conditions on the thoracic structure. The excessive deflection is therefore attributed to factors beyond arm-thorax coupling.

Implications

The findings indicate that regulatory testing procedures employing side oblique pole impacts with shoulder-covering airbags may subject the WorldSID-50M dummy to loading conditions not represented in standard moving deformable barrier protocols. Identifying the mechanisms driving excessive rib deflection has consequences for dummy validation and interpretation of biomechanical response in this expanded testing modality. The negligible contribution of arm-thorax interaction narrows the focus for further investigation toward other geometric or dynamic factors inherent to oblique pole impact geometry.

Scope and limitations

This summary is based on the study abstract and available metadata. It does not include a full analysis of the complete paper, supplementary materials, or underlying datasets unless explicitly stated. Findings should be interpreted in the context of the original publication.