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Assessing Biofidelity of the Test Device for Human Occupant Restraint (THOR) Against Historic Human Volunteer Data
Published November 11, 2013 by The Stapp Association in United States
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The National Aeronautics and Space Administration (NASA) is interested in characterizing the responses of THOR (test device for human occupant restraint) anthropometric test device (ATD) to representative loading acceleration pulse s. Test conditions were selected both for their applicability to anticipated NASA landing scenarios, and for comparison to human volunteer data previously collected by the United States Air Force (USAF).
THOR impact testing was conducted in the fore-to-aft frontal (-x) and in the upward spinal (-z) directions with peak sled accelerations ranging from 8 to 12 G and rise times of 40, 70, and 100ms. Each test condition was paired with historical huma n data sets under similar test conditions that were also conducted on the Horizontal Impulse Accelerator (HIA). A correlation score was calculated for each THOR to human comparison using CORA (CORrelation and Analysis) software. A two -parameter beta distribution model fit was obtained for each dependent variable using maximum likelihood estimation.
For frontal impacts, the THOR head x-acceleration peak response correlated with the human response at 8 and 10G 100ms, but not 10G 70ms. The phase lagged the human response. Head z-acceleration was not correlated. Chest x-acceleration was in phase, had a higher peak response, and was well correlated with lighter subjects (Cora = 0.8 for 46 kg vs. Cora = 0.4 for 126kg). He ad x-displacement had a leading phase. Several subjects responded with the same peak displacement, but the mean of the group was lower. The shoulder x-displacement was in phase but had higher peaks than the human response.
For spinal impacts, the THOR head x-acceleration was not well correlated. Head and chest z-acceleration was in phase, but had a higher peak response. Chest z-acceleration was highly correlated with heavier subjects at lower G pulses (Cora = 0.86 for 125kg at 8G). The human response was variable in shoulder z-displacement, but the THOR was in phase and was comparable to the mean peak response. Head x- and z-displacement was in phase, but had higher peaks. Seat pan forces are well correlated, are in phase, but have a larger peak response than most subjects.
- Chris Perry - Wright Patterson Air Force Base
- Justin Littell - NASA Langley Research Center
- Michael Gernhardt - NASA Johnson Space Center
- Nate Newby - Wyle Science, Technology & Engineering Group
- Jeffrey T. Somers - Wyle Science, Technology & Engineering Group
- Erin E. Caldwell - Wyle Science, Technology & Engineering Group
CitationNewby, N., Somers, J., Caldwell, E., Perry, C. et al., "Assessing Biofidelity of the Test Device for Human Occupant Restraint (THOR) Against Historic Human Volunteer Data," SAE Technical Paper 2013-22-0018, 2013, https://doi.org/10.4271/2013-22-0018.
- Air Force Research Laboratory Biodynamics Data Bank https://biodyn.istdayton.com
- Air Force Safety Center - Aircraft Statistics. Air Force Safety Center 2012 2012 http://www.afsec.af.mil/organizations/aviation/aircraftstatistics/
- Buhrman et al. 2000 A comparison of male and female acceleration responses during laboratory frontal -Gx axis impact tests, (AFRL-HE-WP-TR-2001-0022), United States Air Force Research Laboratory Report http://oai.dtic.mil
- Doczy et al. 2004 The effects of variable helmet weight and subject bracing on neck loading during frontal -gx impact Proc. 43rd Space and Flight Equipment Association (SAFE) Symposium 186 Salt Lake City, UT
- Ferrari , S.L.P. and Cribari-Neto , F. 2004 Beta regression for modeling rates and proportions Journal of Applied Statistics 31 7 799 815
- Gehre et al. 2009 Objective rating of signals using test and simulation responses Proc. 21st Enhanced Safety Vehicles (ESV) Conference 09 0407
- General Dynamics Advanced Information Systems, Variable Weighted Helmet Gx Study 2004 Report of General Dynamics Company https://biodyn.istdayton.com
- Irwin A.L. , Mertz H.J. , Ali M. , Elhagediab A.M. , and Moss S. 2002 Guidelines for assessing the biofidelity of side impact dummies of various sizes and ages Stapp Car Crash (46) paper No. 2002-22-0016 297 319
- Meijer R. , Wisgerhof R. , Wismans J. , and Been B. 2009 Scaling head-neck response data and derivation of 5th percentile female side-impact dummy head-neck response requirements in NBDL test conditions International Journal of Crashworthiness 14 3 233 243
- Mertz H.J. 1984 A procedure for normalizing impact response data SAE Transactions 93 4 paper No. 840884 4.351 4.358
- Miller M. Z. , and Mosher , S. E. 1989 Test Configuration and Data Acquisition System for the Investigation of Human Response to Varied +Gz Impact Duration and Amplitude Test Program (F33615-86-C-0531) DynCorp Scientific Support Division, Wright Patterson Air Force Base https://biodyn.istdayton.com
- National Highway Traffic Safety Administration Traffic Safety Facts 2011 U.S. Department of Transportation 2011 Contract No.: DOT HS 811 754 http://www.nhtsa.gov/Data
- Pellettiere et al. 2011 Anthropomorphic test dummy lumbar load variability Proc. 22nd International Enhanced Saftey of Vehicles Conference 11 0157 Washington, D.C.
- Ridella , S. , and Parent , D. 2011 Modifications to improve durability, usability and biofidelity of the THOR-NTDummy Proceedings 22nd International Enhanced Saftey of Vehicles Conference 11 0312 Washington, D.C.
- Paolino , P. 2001 Maximum likelihood estimation of models with beta-distributed dependent variables Political Analysis 9 4 325 346
- Rangarajan , N. , Shams , T. , Artis , M. , Huang , T. , Haffner , M. , Eppinger , R. , & Maltese , M. 2000 Oblique and Side Impact Performance on the THOR Dummy IRCOBI Montpellier, France 31 40
- Society of Automotive Engineers 2007 Instrumentation for Impact Test - Part 1 - Electronic Instrumentation Warrendale, PA SAE International
- Smithson , M. and Verkuilen , J. 2006 A better lemon squeezer? Maximum likelihood regression with beta-distributed dependent variables Psychological Methods 11 1 54 71
- Strzelecki , J. P. 2005 Characterization of Horizontal Impulse Accelerator Pin Profiles, (AFRL-HE-WP-SR-2006-0057) United States Air Force Research Laboratory Report http://www.stormingmedia.us
- Thunert , C. 2012 CORA Release 3.6 User's Manual http://www.pdb-org.com
- Whitnah , A. M. , and Hawes , D. B. 1971 Statistics Concerning the Apollo Command Module Water Landing, Including the Probability of Occurrence of Various Impact Conditions, Successful Impact, and Body X-Axis Loads NASA Johnson Space Center Houston, TX NASA TM X-2430