This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Modeling the Effects of Seat Belt Pretensioners on Occupant Kinematics During Rollover
Technical Paper
2006-01-0246
ISSN: 0148-7191, e-ISSN: 2688-3627
Annotation ability available
Sector:
Language:
English
Abstract
The results of a number of previous studies have demonstrated that seat-belted occupants can undergo significant upward and outward excursion during the airborne phase of vehicular rollover, which may place the occupant at risk for injury during subsequent ground contacts. Furthermore, testing using human volunteers, ATDs, and cadavers has shown that increasing tension in the restraint system prior to a rollover event may be of value for reducing occupant displacement. On this basis, it may be argued that pretensioning the restraint system, utilizing technology developed and installed primarily for improving injury outcome in frontal impacts, may modify restrained occupant injury potential during rollover accidents. However, the capacity of current pretensioner designs to positively impact the motion of a restrained occupant during rollover remains unclear. Moreover, the pretensioner characteristics necessary to limit occupant motion and head excursion without exacerbating injury potential associated with restraint contact have not been established. In the present study, we utilized pretensioner testing and computational analysis to evaluate the capacity of pretensioners for altering and reducing occupant head excursion during the early phase of a steer-induced rollover. This study builds upon existing MADYMO models that have been validated for the prediction of occupant head, neck and torso kinematics during the airborne phase of vehicle rollover (Newberry et al., 2005; Lai et al., 2005), as well as experiments which evaluated the occupant motion during the trip phase of steer-induced rollover (Yamaguchi et al., 2005). Although there are many approaches to pretensioner design, most employ pyrotechnic energy that is released when a crash is sensed to reduce the effective length of the restraint system. The capacity of such a pretensioner to retract webbing is likely a function of the seatbelt loads at the time of deployment. In the current study, we conducted bench tests of a typical pyrotechnic retractor-based pretensioner to evaluate its capacity to retract webbing at various loads. It was found that applying a transient force function, as quantified in bench testing, could simulate the pretensioner's performance. Additional bench tests were conducted to characterize the transient force pulses of several retractor pretensioners. To evaluate the efficacy of these pretensioners in limiting head excursion in the early phase of rollover, we simulated a steer-induced rollover event using MADYMO. This simulation focused on the time period from steer initiation until first roof contact, and was validated by comparison of simulated motions of the ATD to those measured during the rollover tip-up tests conducted by Yamaguchi et al. (2005). Vertical and lateral excursion of the head and torso were quantified to evaluate pretensioner performance. Pretensioners with characteristics similar to those found in the existing fleet were found to only modestly affect occupant kinematics and head excursion during the early phase of vehicle rollover.
Recommended Content
Authors
- William Newberry - Exponent Failure Analysis Associates, Inc.
- William Lai - Exponent Failure Analysis Associates, Inc.
- Michael Carhart - Exponent Failure Analysis Associates, Inc.
- Darrin Richards - Exponent Failure Analysis Associates, Inc.
- Jeffrey Brown - Exponent Failure Analysis Associates, Inc.
- Christine Raasch - Exponent Failure Analysis Associates, Inc.
Topic
Citation
Newberry, W., Lai, W., Carhart, M., Richards, D. et al., "Modeling the Effects of Seat Belt Pretensioners on Occupant Kinematics During Rollover," SAE Technical Paper 2006-01-0246, 2006, https://doi.org/10.4271/2006-01-0246.Also In
SAE 2006 Transactions Journal of Passenger Cars: Mechanical Systems
Number: V115-6; Published: 2007-03-30
Number: V115-6; Published: 2007-03-30
References
- Arndt, M. Mowry G. Dickerson C. Arndt S. 1995 Evaluation of Experimental Restraints in Rollover Conditions SAE 952712 39th Stapp Car Crash Conference, Society of Automotive Engineers Warrendale, PA
- Arndt, M. 1998 Testing for Occupant Rollover Protection SAE 980213 International Body Engineering Conference and Exposition, Society of Automotive Engineers Warrendale, PA
- Bahling, G. S. Bundorf R. T. Kaspzyk G. S. Moffatt E. A. Orlowski K. F. Stocke J. E. 1990 Rollover and drop tests -- the influence of roof strength on injury mechanics using belted dummies SAE 902314 34th Stapp Car Crash Conference, Society of Automotive Engineers Warrendale, PA
- Bahling, G. S. Bundorf R. T. 1995 “The influence of increased roof strength on belted and unbelted dummies in rollover and drop tests.” J Trauma 38 4 557 63
- Bardini, R. Hiller M. 1999 The Contribution of Occupant and Vehicle Dynamics Simulation to Testing Occupant Safety in Passenger Cars During Rollover SAE 1999-01-0431 , SAE International Congress & Exposition Detroit, MI March 1999 Society of Automotive Engineers Warrendale, Pennsylvania, USA
- Bohman, K. Boström, O Håland, Y. Kullgren, A. 2000 A study of AIS1 neck injury parameters in 168 frontal collisions using a restrained hybrid III dummy SAE 2000-01-SC08 Proceedings of the 44th Stapp Car Crash Conference Atlanta, Georgia The Stapp Association Ann Arbor, Michigan
- Carter, J.W. Habberstad J.L. Croteau J.J. 2002 Comparison of the Controlled Rollover Impact System (CRIS) With the J2114 Rollover Dolly SAE 2002-01-0694 SAE 2002 World Congress & Exhibition Society of Automotive Engineers Warrendale, PA
- Cooper, E.R. Moffatt E.A. Curzon A.M. Smyth B.J. Orlowski K.F. 2001 Repeatable Dynamic Rollover Test Procedure With Controlled Roof Impact SAE 2001-01-0476 SAE 2001 World Congress, Society of Automotive Engineers Warrendale, PA
- Cooperrider, N.K. Thomas T.M. Hammoud S. A. 1990 Testing and Analysis of Vehicle Rollover Behavior SAE 900366 Society of Automotive Engineers Warrendale, PA
- Cooperrider, N.K. Hammoud S. Colwell J. 1998 Characteristics of Soil-Tripped Rollovers SAE 980022 International Congress & Exposition Society of Automotive Engineers Warrendale, PA
- Digges, K. Malliaris A. C. 1998 Crashworthiness safety features in rollover crashes SAE 982296 International Body Engineering Conference and Exposition Society of Automotive Engineers Warrendale, PA
- Eigen, A.M. Examination of rollover crash mechanisms and occupant outcomes Traffic Safety Facts Research Note December 2003 National Center for Statistics and Analysis (NCSA)
- Eppinger, R. 2002 Occupant Restraint Systems Accidental Injury: Biomechanics and Prevention Nahum A. Melvin J. Springer New York
- Hare, B.M. Lewis L.K. Hughes R.J. Ishikawa Y. Iwasaki K. Tsukaguchi K. Doi N. 2002 Analysis of Rollover Restraint Performance With and Without Seat Belt Pretensioner SAE 2002-01-0941 SAE 2002 World Congress & Exhibition Society of Automotive Engineers Warrendale, PA
- Herbst Forrest B. S. Want P. Cheng D. Friedman D. Friedman K. 1996 The ability of three-point safety belts to restrain occupants in rollover crashes 16th International Conference on the Enhanced Safety of Vehicles Melbourne, AUS
- James, M.B. Allsop D.L. Nordhagen R.P. Decker R.L. 1997 Injury mechanisms and field accident data analysis in rollover accidents SAE 970396 SAE Congress Society of Automotive Engineers Warrendale, Pennsylvania, USA
- Lai W Ewers B Richards D Carhart M Newberry W Corrigan CF 2005 Evaluation of Human Surrogates for Rollover SAE 2005-01-0941 SAE 2005 World Congress April 2005 Society of Automotive Engineers Warrendale, PA
- McCoy, R.W. Balavich K.M. 2005 Analysis of a Prototype Electric Retractor Seat Belt Pre-Tensioning Device and Dummy Lateral Motion Prior to Vehicle Rollover SAE 2005-01-0945 SAE 2005 World Congress Society of Automotive Engineers Warrendale, PA
- Miller, J. 1996 Occupant Performance with Constant Force Restraint Systems SAE 960502 SAE International Congress & Exposition Detroit, MI February 1996 Society of Automotive Engineers Warrendale, Pennsylvania, USA Society of Automotive Engineers Warrendale, PA
- Moffatt, E. A. Cooper E. R. et al 1997 Head excursion of seat-belted cadaver, volunteers and Hybrid III ATD in a dynamic/static rollover fixture SAE 973347 41st Annual Stapp Car Crash Conference Society of Automotive Engineers Warrendale, PA, USA
- Moffatt, E.A. Cooper E.R. Orlowski K.F. Marth D.R. Croteau J.J. Carter J.W. 2003 Matched-Pair Rollover Impacts of Rollcaged and Production Roof Cars Using the Controlled Rollover Impact System (CRIS) SAE 2003-01-0172 SAE 2003 World Congress & Exhibition Society of Automotive Engineers Warrendale, PA
- Moffatt, E. Hare B. Hughes R. Lewis L. Iiyama H. Curzon A. Cooper E. 2003 Head excursion of restrained human volunteers and hybrid III dummies in steady state rollover tests Annu Proc Assoc Adv Automot Med 47 445 65
- Moffatt, E. A. Padmanaban J. 2005 “The relationship between vehicle roof strength and occupant injury in rollover crash data.” Association for the Advancement of Automotive Medicine
- Müller, H. E. Linn B. 1998 Seat Belt Pretensioners SAE 980557 SAE International Congress and Exposition Detroit, MI February 1998 Society of Automotive Engineers Warrendale, Pennsylvania, USA
- Newberry, W. Carhart M.R. Lai W. Corrigan C.F. Croteau J. Cooper E. 2005 A computational analysis of the airborne phase of vehicle rollover: occupant head excursion and head-neck posture SAE 2005-01-0943 SAE 2005 World Congress April 2005 Society of Automotive Engineers Warrendale, PA
- Orlowski, K.F. Bundorf R.T. Moffatt E.A. 1985 Rollover Crash Tests--The Influence of Roof Strength on Injury Mechanics SAE 851734 Society of Automotive Engineers Warrendale, PA, USA
- Prasad, P. Chou C. 2002 A Review of Mathematical Occupant Simulation Models Accidental Injury: Biomechanics and Prevention Naham A. Melvin J. Springer New York
- Pywell, J.F. Rouhana, S.W McCleary, J.D. Desaele, K.H. 1997 Characterization of Belt Restraint Systems in Quasistatic Vehicle Rollover Tests 41st Stapp Car Crash Conference Society of Automotive Engineers Warrendale, PA
- Pywell, J.F. Bahling G.S. Werner S.M. 2001 An Examination of Dummy Head Kinematics Prior to Vehicle Rollover SAE 2001-01-0720 SAE 2001 World Congress Society of Automotive Engineers Warrendale, PA, USA
- US DOT National Highway Traffic Safety Administration Federal Motor Vehicle Safety Standards; Roof Crush Resistance NPRM
- Yamaguchi G Carhart M Larson R Richards D Pierce J Raasch C Scher I Corrigan CF 2005 Electromyographic Activity and Posturing of the Human Neck During Rollover Tests SAE 2005-01-0302 SAE 2005 World Congress April 2005 Society of Automotive Engineers Warrendale, PA