scholarly journals A Modified Hybrid III 6-Year-Old Dummy Head Model for Lateral Impact Assessment

2016 ◽  
Vol 2016 ◽  
pp. 1-8
Author(s):  
I. A. Rafukka ◽  
B. B. Sahari ◽  
A. A. Nuraini ◽  
A. Manohar
Keyword(s):  
Impact Assessment ◽  
Head Model ◽  
Drop Height ◽  
Lateral Impact ◽  
Head Acceleration ◽  
Frontal Impact ◽  
Acceleration Response ◽  
Hybrid Iii ◽  
Technology Corporation ◽  
The Difference

Hybrid III six-year-old (6YO) child dummy head model was developed and validated for frontal impact assessment according to the specifications contained in Code of Federal Regulations, Title 49, Part 572.122, Subpart N by Livermore Software Technology Corporation (LSTC). This work is aimed at improving biofidelity of the head for frontal impact and also extending its application to lateral impact assessment by modifying the head skin viscoelastic properties and validating the head response using the scaled nine-year-old (9YO) child cadaver head response recently published in the literature. The modified head model was validated for two drop heights for frontal, right, and left parietal impact locations. Peak resultant acceleration of the modified head model appeared to have good correlation with scaled 9YO child cadaver head response for frontal impact on dropping from 302 mm height and fair correlation with 12.3% difference for 151 mm drop height. Right parietal peak resultant acceleration values correlate well with scaled 9YO head experimental data for 153 mm drop height, while fair correlation with 16.4% difference was noticed for 302 mm drop height. Left parietal, however, shows low biofidelity for the two drop heights as the difference in head acceleration response was within 30%. The modified head model could therefore be used to estimate injuries in vehicle crash for head parietal impact locations which cannot be measured by the current hybrid III dummy head model.

Development of an Improved Dummy Head for Use in Helmet Certification Tests

2000 ◽  
Author(s):  
Eric H. L. A. van den Bosch ◽  
Martijn W. B. M. Leensen ◽  
Nancy H. M. Klomp ◽  
Fons A. A. H. J. Sauren ◽  
Jac S. H. M. Wismans
Keyword(s):  
Brain Structure ◽  
Evaluation Process ◽  
Drop Test ◽  
Head Acceleration ◽  
First Order ◽  
Certification Tests ◽  
Hybrid Iii

Abstract First order improvements to the rigid headform, used in current helmet certification tests, are made by introducing a skull and brain structure. In developing the new headform certain requirements were taken into consideration. The new headform appears to meet all requirements but one. The 200 mm drop test with Hybrid-III skin padding on the anvil resulted in too low resultant linear head accelerations. Using a stiffer, more realistic padding on the anvil resulted in a resultant linear head acceleration which satisfies the requirements (100 – 150 g). The padding plays an important role in the evaluation process. Because of the deformable skull, a fairly stiff padding has to be used in order to let the resultant linear head acceleration satisfy the requirements. In contrast to the 200 mm drop test experiments, the padding properties of the skin are of no importance when an EPS padding is placed between the skin and the anvil.

Finite element comparison of human and Hybrid III responses in a frontal impact

2015 ◽  
Vol 85 ◽  
pp. 125-156 ◽  
Author(s):  
Kerry A. Danelson ◽  
Adam J. Golman ◽  
Andrew R. Kemper ◽  
F. Scott Gayzik ◽  
H. Clay Gabler ◽  
...  
Keyword(s):  
Finite Element ◽  
Frontal Impact ◽  
Hybrid Iii

Human Response to Dynamic Rollover Conditions

2003 ◽  
Author(s):  
Jack Bish ◽  
Terence Honikman ◽  
Jason Sigel ◽  
Carl Nash ◽  
Donald Friedman
Keyword(s):  
Motor Vehicle ◽  
Rotation Axis ◽  
Test Subject ◽  
Rotational Axis ◽  
Human Response ◽  
Passenger Compartment ◽  
Hybrid Iii ◽  
Drop Tests ◽  
Vehicle Rollover ◽  
The Difference

To date, human responses in motor vehicle rollover accidents have been studied through the use of Hybrid III dummies in dolly vehicle rollover tests, quasi-static spit tests where the vehicle and occupant are rotated slowly about the rotation axis of the spit fixture, computer simulations and vehicle drop tests. To demonstrate human responses to dynamic rollover conditions more accurately we designed and built a fixture to accommodate a passenger compartment in a hoop structure that rotates as it translates. The rotational axis of the hoop structure is offset from the rotational axis of the passenger compartment to replicate vehicle center of gravity motion seen in dolly rollover tests. Testing showed the difference in restraint behavior depending upon whether the occupant was seated on the near (initially leading) or far side. It demonstrated that human and Hybrid III dummy neck response is very different. The human test subject received no injuries from diving into the roof of the passenger compartment even though this is the predicted injury mechanism reported in several technical papers.

The Influence of Hard Hat Design Features on Head Acceleration Attenuation

2020 ◽  
pp. 1-7
Author(s):  
Arthur Alves Dos Santos ◽  
James Sorce ◽  
Alexandra Schonning ◽  
Grant Bevill
Keyword(s):  
Lead Shot ◽  
Construction Site ◽  
Head Acceleration ◽  
Protective Capacity ◽  
Design Features ◽  
Shell Design ◽  
Hybrid Iii ◽  
Hard Hat ◽  
Head Neck

This study evaluated the performance of 6 commercially available hard hat designs—differentiated by shell design, number of suspension points, and suspension tightening system—in regard to their ability to attenuate accelerations during vertical impacts to the head. Tests were conducted with impactor materials of steel, wood, and lead shot (resembling commonly seen materials in a construction site), weighing 1.8 and 3.6 kg and dropped from 1.83 m onto a Hybrid III head/neck assembly. All hard hats appreciably reduced head acceleration to the unprotected condition. However, neither the addition of extra suspension points nor variations in suspension tightening mechanism appreciably influenced performance. Therefore, these results indicate that additional features available in current hard hat designs do not improve protective capacity as related to head acceleration metrics.

Study on the Difference of Frontal Impact Response among People of Different Sizes

2010 ◽  
Vol 34-35 ◽  
pp. 111-116 ◽  
Author(s):  
Li Bo Cao ◽  
Chong Zhen Cui ◽  
Ning Yu Zhu ◽  
Huan Chen
Keyword(s):  
Human Body ◽  
Injury Risk ◽  
Simulation Models ◽  
Restraint System ◽  
Frontal Impact ◽  
Occupant Restraint System ◽  
Impact Simulation ◽  
The Difference ◽  
Human Body Models ◽  
Multi Body

In this article, seven frontal impact simulation models with same restraint system and different human body models were established through the use of multi-body kinematics software MADYMO. The injuries in head, chest and femurs of different human models and the differences of these injuries were analyzed in detail. The weighted injury criterion was adopted to evaluate the overall injuries of different human body models. The results shows that the injury risk of smaller human body is much higher than the taller human body, and existing occupant restraint system that protects the 50th percentile American occupant well protects other size occupant poorly.

scholarly journals The Effects of Curtain Airbag on Occupant Kinematics and Injury Index in Rollover Crash

2018 ◽  
Vol 2018 ◽  
pp. 1-12
Author(s):  
Hongyun Li ◽  
Chengyue Jiang ◽  
Dong Cui ◽  
Shuang Lu
Keyword(s):  
Restraint System ◽  
Head Acceleration ◽  
Physical Test ◽  
Injury Index ◽  
Hybrid Iii ◽  
Protection Area ◽  
Occupant Injuries ◽  
Occupant Kinematics ◽  
Head And Neck Injury ◽  
Rollover Crash

Background. Occupant injuries in rollover crashes are associated with vehicle structural performance, as well as the restraint system design. For a better understanding of the occupant kinematics and injury index in certain rollover crash, it is essential to carry out dynamic vehicle rollover simulation with dummy included. Objective. This study focused on effects of curtain airbag (CAB) parameters on occupant kinematics and injury indexes in a rollover crash. Besides, optimized parameters of the CAB were proposed for the purpose of decreasing the occupant injuries in such rollover scenario. Method and Material. The vehicle motion from the physical test was introduced as the input for the numerical simulation, and the 50% Hybrid III dummy model from the MADYMO database was imported into a simulation model. The restraint system, including a validated CAB module, was introduced for occupant kinematics simulation and injury evaluation. TTF setting, maximum inflator pressure, and protection area of the CAB were analysed. Results. After introducing the curtain airbag, the maximum head acceleration was reduced from 91.60 g to 49.52 g, and the neck Mx and neck Fz were reduced significantly. Among these CAB parameters, the TTF setting had the largest effect on the head acceleration which could reduce 8.6 g furthermore after optimization. The neck Fz was decreased from 3766.48 N to 2571.77 N after optimization of CAB protection area. Conclusions. Avoiding hard contact is critical for the occupant protection in the rollover crashes. The simulation results indicated that occupant kinematics and certain injury indexes were improved with the help of CAB in such rollover scenario. Appropriate TTF setting and inflator selection could benefit occupant kinematics and injury indexes. Besides, it was advised to optimize the curtain airbag thickness around the head contact area to improve head and neck injury indexes.

Development of Validation Metrics for Vehicle Frontal Impact Simulation

2007 ◽  
Author(s):  
R. J. Yang ◽  
G. Li ◽  
Y. Fu
Keyword(s):  
Step Function ◽  
Evaluation Procedure ◽  
Frontal Impact ◽  
Physical Test ◽  
Frontal Crash ◽  
Validation Metrics ◽  
Impact Simulation ◽  
Commercial Code ◽  
The Difference ◽  
And Mathematics

This research addresses the development of validation metrics for vehicle frontal impact simulation. The model validation metrics provide a quantified measurement of the difference between CAE simulation and physical test. They are useful to develop an objective model evaluation procedure for eventually achieving the goal of zero or near zero prototyping. In this research, full frontal crash pulses are chosen as the key items to be compared in the vehicle frontal impact simulation. Both physics- and mathematics-based metrics are investigated. The physics-based metric include a method of using a simplified step function representation and the mathematics-based metrics include methods of wavelet decomposition, corridor violation plus area, and metrics used in a commercial code ADVISER, respectively. They are all correlated to subject matter experts’ rating through optimal weightings. A new metric, considering variabilities from both experts and metrics for frontal crash pulse, is proposed. One example is used to demonstrate its application.

Effects of Underground Structure on Acceleration Response of Site

2011 ◽  
Vol 368-373 ◽  
pp. 2791-2794 ◽  
Author(s):  
Chao Sun ◽  
Qing Wang
Keyword(s):  
Numerical Simulation ◽  
Response Spectrum ◽  
Underground Structure ◽  
Ground Surface ◽  
Acceleration Response ◽  
The Difference ◽  
Peak Value

Through numerical simulation，the article analyzes the difference of ground surface acceleration response under the condition of free site and underground structure. The result shows: compared with free site, the underground structure has a greater influence on the peak value of ground surface acceleration and response spectrum. The paper also presents the influencing regularities.

Validation of a Wireless Head Acceleration Measurement System for Use in Soccer Play

2010 ◽  
Vol 26 (4) ◽  
pp. 424-431 ◽  
Author(s):  
Erin Hanlon ◽  
Cynthia Bir
Keyword(s):  
Measurement System ◽  
Cross Correlation ◽  
Angular Acceleration ◽  
Strong Relationship ◽  
Head Acceleration ◽  
Acceleration Measurement ◽  
Hybrid Iii ◽  
Cross Correlations ◽  
Rms Error ◽  
Soccer Heading

Soccer heading has been studied previously with conflicting results. One major issue is the lack of knowledge regarding what actually occurs biomechanically during soccer heading impacts. The purpose of the current study is to validate a wireless head acceleration measurement system, head impact telemetry system (HITS) that can be used to collect head accelerations during soccer play. The HIT system was fitted to a Hybrid III (HIII) head form that was instrumented with a 3-2-2-2 accelerometer setup. Fifteen impact conditions were tested to simulate impacts commonly experienced during soccer play. Linear and angular acceleration were calculated for both systems and compared. Root mean square (RMS) error and cross correlations were also calculated and compared for both systems. Cross correlation values were very strong withr= .95 ± 0.02 for ball to head forehead impacts andr= .96 ± 0.02 for head to head forehead impacts. The systems showed a strong relationship when comparing RMS error, linear head acceleration, angular head acceleration, and the cross correlation values.

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