Optimizing Seat Belt and Airbag Designs for Rear Seat Occupant Protection in Frontal Crashes

Authors: Jingwen Hu and Matthew P. Reed—University of Michigan Transportation Research Institute; Jonathan D. Rupp—Emory University School of Medicine; Kurt Fischer, Paul Lange, and Angelo Adler—ZF TRW Automotive Holdings Corp

Abstract

Recent field data have shown that the occupant protection in vehicle rear seats failed to keep pace with advances in the front seats likely due to the lack of advanced safety technologies. The objective of this study was to optimize advanced restraint systems for protecting rear seat occupants with a range of body sizes under different frontal crash pulses. Three series of sled tests (baseline tests, advanced restraint trial tests, and final tests), MADYMO model validations against a subset of the sled tests, and design optimizations using the validated models were conducted to investigate rear seat occupant protection with 4 Anthropomorphic Test Devices (ATDs) and 2 crash pulses. The sled tests and computer simulations were conducted with a variety of restraint systems including the baseline rear-seat 3-point belt, 3-point belts with a pre-tensioner, load limiter, dynamic locking tongue, 4-point belts, inflatable belts, Bag in Roof (BiR) concept, and Self Conforming Rear seat Air Bag (SCaRAB) concept. The results of the first two sled series demonstrated that the baseline 3-point belt system are associated with many injury measures exceeding injury assessment reference values (IARVs); showed the significance of crash pulse and occupant size in predicting injury risks; and verified the potential need of advanced restraint features for better protecting the rear-seat occupants. Good correlations between the tests and simulations were achieved through a combination of optimization and manual fine-tuning, as determined by a correlation method. Parametric simulations showed that optimized belt-only designs (3-point belt with pre-tensioner and load limiter) met all of the IARVs under the soft crash pulse but not the severe crash pulse, while the optimized belt and SCaRAB design met all the IARVs under both the soft and severe crash pulses. Two physical prototype restraint systems, namely an “advanced-belt only” design and an “advanced-belt and SCaRAB” design, were then tested in the final sled series. With the soft crash pulse, both advanced restraint systems were able to reduce all the injury measures below the IARVs for all four ATDs. Both advanced restraint systems also effectively reduced almost all the injury measures for all ATDs under the severe crash pulse, except for the THOR. The design with the advanced-belt and SCaRAB generally provided lower injury measures than those using the advanced belt-only design. This study highlighted the potential benefit of using advanced seatbelt and airbag systems for rear-seat occupant protection in frontal crashes.

Type: Full Paper

Keywords: Rear seat, occupant protection, frontal crash test, crash simulation, restraint optimization, seat belt, airbag

© Stapp Association, 2017

Access Additional Papers from This Volume

View additional Full Papers from the Stapp Car Crash Journal, Volume 61.

• Analysis of Repeatability and Reproducibility Standards of ATD Response for the Correlation Method
  Authors: Lan Xu and Guy Nusholtz—FCA US LLC, USA Abstract Statistical methods, using the entire time-history, can be used to…
• Application of Extreme Value Theory to Crash Data Analysis
  Authors: Lan Xu and Guy Nusholtz—FCA US LLC, USA Abstract A parametric model obtained by fitting a set of data…
• Association of Impact Velocity with Serious-Injury and Fatality Risks to Cyclists in Commercial Truck-Cyclist Accidents
  Authors: Yasuhiro Matsui—National Traffic Safety and Environment Laboratory, Japan; Shoko Oikawa—Tokyo Metropolitan University; Kazuhiro Sorimachi, Akira Imanishi, and Takeshi Fujimura—Isuzu…
• Biofidelity Evaluation of the THOR and Hybrid III 50th Percentile Male Frontal Impact Anthropomorphic Test Devices
  Authors: Daniel Parent, Matthew Craig, Kevin Moorhouse—National Highway Traffic Safety Administration Abstract The objective of this study is to present…
• Biomechanics of Lumbar Motion-Segments in Dynamic Compression
  Authors: Mike W. J. Arun, Prasannaah Hadagali, Klaus Driesslein, William Curry, Narayan Yoganandan, and Frank A. Pintar—Department of Neurosurgery, Medical…
• Development of the CAVEMAN Human Body Model: Validation of Lower Extremity Sub-Injurious Response to Vertical Accelerative Loading 
  Authors: Kent Butz, Chad Spurlock, Rajarshi Roy, Cameron Bell, Paul Barrett, Aaron Ward, Xudong Xiao, Allen Shirley, Colin Welch, Kevin…
• Human Foot-Ankle Injuries and Associated Risk Curves from Under Body Blast Loading Conditions
  Authors: Sajal Chirvi, Narayan Yoganandan, Mike Schlick, William Curry—Department of Neurosurgery, Medical College of Wisconsin/VA Medical Center; Frank Pintar—Department of…
• Human Shoulder Response to High Velocity Lateral Impact
  Authors: Matthieu Lebarbé—CEESAR, Nanterre, France; Philippe Vezin—Univ Lyon, Université Claude Bernard Lyon 1, IFSTTAR, LBMC UMR_T9406, F69622, Lyon, France; Frédéric…
• Neck Injury Response in High Vertical Accelerations and its Algorithmical Formalization to Mitigate Neck Injuries
  Authors: Julie Klima, Jian Kang, AnnMarie Meldrum, Steven Pankiewicz—Tank Automotive Research, Development, and Engineering Center Abstract Tank Automotive Research, Development…
• New Reference PMHS Tests to Assess Whole-Body Pedestrian Impact Using a Simplified Generic Vehicle Front-End
  Authors: Eric Song, Philippe Petit, and Xavier Trosseille—LAB PSA Renault; Jérôme Uriot, Pascal Potier, and Denis Dubois—CEESAR; Richard Douard—Université Paris…
• Occupant Kinematics in Simulated Autonomous Driving Vehicle Collisions: Influence of Seating Position, Direction and Angle
  Authors: Yuichi Kitagawa, Shigeki Hayashi, Katsunori Yamada, Mitsuaki Gotoh—Toyota Motor Corporation Abstract This two-part study analyzed occupant kinematics in simulated…
• Optimal Specifications for the Advanced Pedestrian Legform Impactor
  Authors: Takahiro Isshiki, Jacobo Antona-Makoshi, and Atsuhiro Konosu—Japan Automobile Research Institute; Yukou Takahashi—Japan Automobile Manufacturers Association Abstract This study addresses…
• Optimizing Seat Belt and Airbag Designs for Rear Seat Occupant Protection in Frontal Crashes
  Authors: Jingwen Hu and Matthew P. Reed—University of Michigan Transportation Research Institute; Jonathan D. Rupp—Emory University School of Medicine; Kurt…
• Strain-rate Dependency of Axonal Tolerance for Uniaxial Stretching
  Authors: Hiromichi Nakadate, Evrim Kurtoglu, Hidenori Furukawa, Shoko Oikawa, and Shigeru Aomura—Graduate School of System Design, Tokyo Metropolitan University; Akira…

Looking for Something Else?