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Assessment of a Three-Point Restraint System with a Pre-tensioned Lap Belt and an Inflatable, Force-Limited Shoulder Belt
Published November 07, 2011 by The Stapp Association in United States
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This study investigates the performance of a 3-point restraint system incorporating an inflatable shoulder belt with a nominal 2.5-kN load limiter and a non-inflatable lap belt with a pretensioner (the “Airbelt”). Frontal impacts with PMHS in a rear seat environment are presented and the Airbelt system is contrasted with an earlier 3-point system with inflatable lap and shoulder belts but no load-limiter or pretensioners, which was evaluated with human volunteers in the 1970s but not fully reported in the open literature (the “Inflataband”). Key differences between the systems include downward pelvic motion and torso recline with the Inflataband, while the pelvis moved almost horizontally and the torso pitched forward with the Airbelt. One result of these kinematic differences was an overall more biomechanically favorable restraint loading but greater maximum forward head excursion with the Airbelt. The Airbelt is shown to generate generally lower head, neck, and thoracic injury metrics and PMHS trauma than other, non-inflatable rear-seat restraint concepts (viz., a standard 3-point belt and a pre-tensioned shoulder belt with a progressive load limiter). Further study is needed to evaluate the Airbelt system for different size occupants (e.g., children), non-frontal impact vectors, and for out-of-position occupants and to allow the results with this particular system to be generalized to a broader range of Airbelt designs.
- Richard Kent - University of Virginia Center for Applied Biomechanics
- Francisco J. Lopez-Valdes - University of Virginia Center for Applied Biomechanics
- Nate J. Dennis - University of Virginia Center for Applied Biomechanics
- David Lessley - University of Virginia Center for Applied Biomechanics
- Jason Forman - University of Navarra
- Kazuo Higuchi - Takata Corp.
- Hiromasa Tanji - Takata Corp.
- Tadayuki Ato - Takata Corp.
- Hikaru Kameyoshi - Takata Corp.
- Kristy Arbogast - The Children's Hospital of Philadelphia
CitationKent, R., Lopez-Valdes, F., Dennis, N., Lessley, D. et al., "Assessment of a Three-Point Restraint System with a Pre-tensioned Lap Belt and an Inflatable, Force-Limited Shoulder Belt," SAE Technical Paper 2011-22-0007, 2011, https://doi.org/10.4271/2011-22-0007.
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