Download or read book Development of Response Surface Data on the Head Injury Criteria Associated with Various Aircraft and Automotive Head Impact Scenarios written by Prasanna Vadanan Nallan Chakravarthy and published by . This book was released on 2016 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: Safety of passengers in both automotive and aircraft is always looked upon for more advancement in providing better safety and minimizing the injuries/fatalities during crashes. Among the injuries which are incurred onto the occupants in aviation and automotive accidents, the head injuries are the most fatal and severe type of injury. In aircraft accidents, mostly in the event of air turbulence or emergency landing, the passengers seated behind bulkheads or interior walls have a higher chance of head impact onto these structures. Similarly, the vehicle safety is considered to be quiet important for automobile manufacturers as well as customers. Among all automobile crashes, frontal impact collisions are the most common types of crash scenario. The most observed injuries in these crashes are caused by the impact of the head to the steering wheel, windshield, etc. This thesis presents an investigation and development of response surface data on the Head Injury Criteria (HIC) during frontal crashes in both automotive and aircraft accidents. Consideration is made relative to the Federal Aviation Regulations (FARs) for the aircraft industry and the US-NCAP (New Car Assessment Program) protocol for frontal impact crashes in automotive industry. For this purpose, a hybrid III 50th percentile dummy is utilized in the occupant modeling code MADYMO to investigate the variations of the HIC with different parameters such as impact speed, impact angle, seat belt properties, seat pitch distances, and stiffness or material properties of the impact surface. Finally, a Design-of-Experiments (DOE)/Kriging model is utilized to generate response surface data on the HIC, using the sample results obtained from the MADYMO computer models. The collective results of the many simulations as surface plots from this study could be of significant use to the designers of automotive seats and aircraft interiors and in coming up with the most promising designs for occupant head impact protection in various frontal crash scenarios.
Download or read book Sensitivity Analysis of Factors Influencing the Head Injury Criteria Evaluation Using Computational Simulations with a Free motion Headform Model written by Sai Srinivas Akhil Hawaldar and published by . This book was released on 2019 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: In aviation and automotive crash scenarios, head injuries are the most severe and fatal type among all the injuries incurred to the occupants. Head injuries typically occur when the head of the occupant comes in to contact with any aircraft cabin interiors, bulkheads, car steering wheel, windshield, etc. The compliance with the Head Injury Criteria (HIC) regulatory requirement is a significant concern for aircraft and automotive industries due to the importance of occupant head injury protection as well as the cost associated with the certification. The objective of this research is to examine various factors that might influence the resulting HIC value in both automotive and aircraft crash scenarios. A Hybrid-III free-motion headform (FMH) model is utilized for this purpose to investigate the variations of the HIC with different combinations of the target conditions (material, thickness, boundary conditions, and friction, etc.), as well as the impact conditions (impact velocity and impact angle). All the computational impact simulations are conducted in the LS-DYNA Finite Element (FE) software. A parametric study is then carried out using the Taguchi methodology and design of experiments (DOE), with combinations of different target and impact conditions. The analysis of variance (ANOVA) approach is utilized to study the relative percentage contribution of these conditions on the resulting HIC evaluation. The sensitivity analysis is carried out to investigate the influence of impact conditions over target conditions, and vice versa. Finally, optimal parameters for the target conditions, for the given impact conditions, are arrived at as a design tool. The significance of various factors among both target and impact conditions are thus identified.
Download or read book Mitigation written by Jeffrey A Pike and published by SAE International. This book was released on 2011-09-08 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nearly 50,000 Americans die from brain injuries annually, with approximately half of all Traumatic Brain Injuries (TBI) being transportation-related. TBI is a critical and ever-evolving safety topic, with equally important components of injury prevention, consequences, and treatment. This book is part of a 3-volume set which presents a comprehensive look at recent head injury research and applies protective strategies to various injury scenarios, such as passenger vehicles, sports, and blast injuries, or to a particular demographic group, such as children or seniors. This volume features 14 technical papers. Editor Jeffrey A. Pike has selected the most relevant technical papers spanning the early 1990s through the beginning of 2011, including several older papers which provide an essential historical perspective. Each volume in the series also includes a table of references arranged by topic and a new chapter tying together anatomy, injury, and injury mechanism topics. Buy the Set and Save! Head Injury Biomechanics The three-volume set consists of these individual volumes: Head Injury Biomechanics, Volume 1--The Skull Head Injury Biomechanics, Volume 2--The Brain Head Injury Biomechanics, Volume 3--Mitigation
Download or read book Assessment of Head and Neck Injury Potential During Aircraft Longitudinal Impacts written by Richard L. DeWeese and published by . This book was released on 2017 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The risk of head-neck injuries was evaluated for certain aircraft seat and interior configurations in aircraft longitudinal impacts. Two loading scenarios for the head-neck system were investigated: inertial (noncontact) loading in posterior-anterior and lateral direction using a forward facing seat and side facing couch, respectively, and contact loading through impacts of the head with typical aircraft interior components. The sled tests simulate an impact along the longitudinal axis of the aircraft; however, the seat orientation causes either forward or lateral occupant loading. The FAA Hybrid III was used in the occupant-forward impacts, and the ES-2 Anthropomorphic Test Device (ATD) was used in the occupant-lateral impacts. The ATDs utilized a unique 9-accelerometer array (NAP) bracket. Techniques were applied to derive rotational acceleration and velocity from the NAP. Head rotational velocities were cross-validated using photometric techniques. Both ATDs were also equipped with upper and lower neck 6-axis load cells. The restraint configurations investigated for inertial loading were a forward facing pilot seat with a 4-point restraint, a forward facing passenger seat with a lap belt restraint, and a side facing passenger seat with a 3-point restraint. The contact load configurations utilized a forward facing passenger seat with a lap belt restraint with either a passenger seat back or simulated class divider as impact surfaces. The neck injury potential was evaluated by the Federal Motor Vehicle Safety Standards Nij criterion, using the neck loads at the occipital condyle level. The NAP data were used to evaluate head injury potential with multiple versions of the Head Injury Criteria (HIC), Skull Fracture Correlate, and the Brain Injury Criteria (BrIC). Neck injury was not a significant risk in most of the forward facing configurations tested; the only test with a Nij value above the limit also exceeded the HIC limit. For the side facing test configurations, neck injury was a significant risk, particularly for seating systems that did not provide effective upper body support. For head injury risk, significant differences were seen between the aviation and automotive versions of HIC. In several tests, aviation HIC was not calculated because there was no contact, but the automotive versions of HIC and BrIC suggest a risk of head injury. Overall, these results indicate that using both HIC and BrIC to evaluate seating systems could provide a safety benefit by directly evaluating the risk of skull fracture and traumatic brain injury."--Abstract.
Download or read book Head Injury Simulation in Road Traffic Accidents written by Fábio A. O. Fernandes and published by Springer. This book was released on 2018-04-27 with total page 107 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this work the development of a new geometrically detailed finite element head model is presented. Special attention is given to sulci and gyri modelling, making this model more geometrically accurate than others currently available. The model was validated against experimental data from impact tests on cadavers, specifically intracranial pressure and brain motion. Its potential is shown in an accident reconstruction case with injury evaluation by effectively combining multibody kinematics and finite element methodology.
Download or read book Investigations of Modern day Head Injuries written by David Bradford Stark and published by . This book was released on 2019 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: While concussions are a mild brain injury with a large prevalence, drone, or UAS head impacts pose a risk for more traumatic head injuries but currently have a low prevalence. However, the rate of drone impacts is likely to increase as the industry is expanding at a rapid rate and benefits associated with drone use are driving new federal regulations which would allow for more widespread UAS flights over people. Before UAS flight over people is made legal, the risk of human injury due to UAS impacts must be quantified and understood. For this work, UAS head impacts were carried out on post-mortem human surrogates (PMHS) (i.e. cadavers) and the Hybrid III ATD. PMHS impacts were used to assess the likelihood of injury resulting from UAS impacts, while ATD tests were compared to matched PMHS data to assess how well the ATD replicates human response in this new impact scenario. The study’s main conclusions were that serious head injuries are possible as a result of UAS impacts and additional investigation is required to determine appropriate injury criteria for use in predicting the severity of head injuries in UAS impact cases. Additionally, the ATD response did not replicate that of the PMHS, specifically in angled or vertical impacts; thus, caution should be exercised when using the Hybrid III ATD to assess the risk of injury in UAS impact scenarios.
Download or read book Impact Head Injury written by North Atlantic Treaty Organization. Advisory Group for Aerospace Research and Development. Aerospace Medical Panel. Specialists' Meeting and published by . This book was released on 1997 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Brain Injury a Research Initiative to Develop Improved Head Injury Tolerance Criteria Summary Final Report written by Lawrence E. Thibault and published by . This book was released on 1989 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Survey of Current Head Injury Research written by National Advisory Neurological Diseases and Stroke Council. Subcommittee on Head Injury and published by . This book was released on 1969 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: 92 annotated references to current projects and 412 references to journal articles appearing in Index medicus January through June, 1969. General topical arrangements in both sections. Separate indexes of senior investigators engaged in current projects devoted exclusively to head injuries and those devoted partly to head injuries, general index of all investigators.
Download or read book Human Impact Response written by W. King and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 401 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Head Impact Injury Mitigation to Vehicle Occupants written by Ermias Koricho and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Traumatic Brain Injuries (TBI) occur approximately 1.7 million times each year in the U.S., with motor vehicle crashes as the second leading cause of TBI-related hospitalizations, and the first leading cause of TBI-related deaths among specific age groups. Several studies have been conducted to better understand the impact on the brain in vehicle crash scenarios. However, the complexity of the head is challenging to replicate numerically the head response during vehicle crash and the resulting traumatic Brain Injury. Hence, this study aims to investigate the effect of vehicle structural padding and head form modeling representation on the head response and the resulting causation and Traumatic Brain Injury (TBI). In this study, a simplified and complex head forms with various geometries and materials including the skull, cerebrospinal fluid (CSF), neck, and muscle were considered to better understand and predict the behavior of each part and their effect on the response of the brain during an impact scenario. The effect of padding thickness was also considered to further analyze the interaction of vehicle structure and the head response. The numeral results revealed that the responses of the head skull and the brain under impact load were highly influenced by the padding thickness, head skull material modeling and assumptions, and neck compliance. Generally, the current work could be considered an alternative insight to understand the correlation between vehicle structural padding, head forms, and materials modeling techniques, and TBI resulted from a vehicle crash.
Download or read book Sports Related Concussions in Youth written by National Research Council and published by National Academies Press. This book was released on 2014-02-04 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past decade, few subjects at the intersection of medicine and sports have generated as much public interest as sports-related concussions - especially among youth. Despite growing awareness of sports-related concussions and campaigns to educate athletes, coaches, physicians, and parents of young athletes about concussion recognition and management, confusion and controversy persist in many areas. Currently, diagnosis is based primarily on the symptoms reported by the individual rather than on objective diagnostic markers, and there is little empirical evidence for the optimal degree and duration of physical rest needed to promote recovery or the best timing and approach for returning to full physical activity. Sports-Related Concussions in Youth: Improving the Science, Changing the Culture reviews the science of sports-related concussions in youth from elementary school through young adulthood, as well as in military personnel and their dependents. This report recommends actions that can be taken by a range of audiences - including research funding agencies, legislatures, state and school superintendents and athletic directors, military organizations, and equipment manufacturers, as well as youth who participate in sports and their parents - to improve what is known about concussions and to reduce their occurrence. Sports-Related Concussions in Youth finds that while some studies provide useful information, much remains unknown about the extent of concussions in youth; how to diagnose, manage, and prevent concussions; and the short- and long-term consequences of concussions as well as repetitive head impacts that do not result in concussion symptoms. The culture of sports negatively influences athletes' self-reporting of concussion symptoms and their adherence to return-to-play guidance. Athletes, their teammates, and, in some cases, coaches and parents may not fully appreciate the health threats posed by concussions. Similarly, military recruits are immersed in a culture that includes devotion to duty and service before self, and the critical nature of concussions may often go unheeded. According to Sports-Related Concussions in Youth, if the youth sports community can adopt the belief that concussions are serious injuries and emphasize care for players with concussions until they are fully recovered, then the culture in which these athletes perform and compete will become much safer. Improving understanding of the extent, causes, effects, and prevention of sports-related concussions is vitally important for the health and well-being of youth athletes. The findings and recommendations in this report set a direction for research to reach this goal.
Download or read book Investigation of Primary Blast Injury and Protection Using Sagittal and Transverse Finite Element Head Models written by Dilaver Singh and published by . This book was released on 2015 with total page 191 pages. Available in PDF, EPUB and Kindle. Book excerpt: The prevalence of blast related mild traumatic brain injury (mTBI) in recent military conflicts, attributed in part to an increased exposure to improvised explosive devices (IEDs), requires further understanding to develop methods to mitigate the effects of primary blast exposure. Although general blast injury has been studied extensively since the 1950's, many aspects of mTBI remain unclear, including specific injury mechanisms and injury criteria. The purpose of this work was to develop finite element models to investigate primary blast injury to the head in the loading regimes relevant to mTBI, to use the models to determine the response of the brain tissue, and ultimately to investigate the effectiveness of helmets on response mitigation. Since blast is inherently a wave dominated phenomena, finite element models require relatively small elements to resolve complex pressure wave transmission and reflections in order to accurately predict tissue response. Furthermore, mesh continuity between the tissue structures is necessary to ensure accurate wave transmission. The computational limitations present in analyzing a full three dimensional blast head model led to the development of sagittal and transverse planar models, which provide a fully coupled analysis with the required mesh resolution while remaining computationally feasible. The models consist of a single layer of solid hexahedral elements, and include all of the relevant tissues in the head including the skin, muscle, skull, cerebrospinal fluid, and brain. The sagittal and transverse models were validated using head kinematics against experimental data on Hybrid III head-forms exposed to free-field blast. The peak head accelerations of the models was in close agreement to the experimental data, and the HIC15 predictions were in reasonable agreement. In addition, the models were validated for intracranial pressure using experimental data from cadaveric heads exposed to shock tube loading. The intracranial pressures predicted by the sagittal and transverse models was in good agreement at the frontal, temporal, and parietal locations, and in fair agreement at the occipital location. A simplified three dimensional ellipsoid study was undertaken to verify that sagittal and transverse planar models are capable of representing a three dimensional shape. This investigation confirmed that the pressures predicted by the planar models are accurate at the frontal, temporal, and parietal locations, although underpredicted at the occipital location due to three dimensional wave superposition that becomes significant at the occipital region. The sagittal and transverse models were run at three representative blast load cases, corresponding to 5 kg of C4 at 3, 3.5, and 4 m standoff distances, and the resulting intracranial strains and pressures were investigated. The sagittal and transverse models report peak principal strains of 0.035 - 0.062 and 0.053 - 0.087 respectively. In comparison to the available threshold values of principal strain in the literature, the strains predicted by the models are generally low. While the strains reported by the models in primary blast are small, the strain rates are significantly greater (ranging from 226 - 571 s-1) than those seen in typical automotive or blunt impact scenarios. Furthermore, the models report that significant levels of intracranial pressure, on the order of several atmospheres, can be generated in the brain tissue during primary blast exposure. The peak pressures in the brain tissue for both models typically exceeded the existing injury thresholds for intracranial that are available in the literature. However, these existing criteria were generally developed for automotive crash scenarios, so may not be suitable for the short durations inherent to blast. The magnitudes of intracranial pressure increased significantly with increasing blast load severity, while changes in principal strain were relatively small, and peak strains were low in all three load cases, suggesting that pressure may be a more appropriate injury response metric for blast injury. The sagittal and transverse models were outfitted with various military helmet configurations and materials to investigate the influence of helmet visors, foam lining presence and density, and Kevlar material stiffness on the protective properties of the helmet. The peak head accelerations and intracranial pressures were compared for low and high intensity blast loads. In general, the presence of a helmet resulted in reduced peak head accelerations, and a greater reduction was reported with the addition of a half-visor and full-visor. The presence of a visor significantly reduced positive intracranial pressures in all cases, although increased the maximum negative pressures in some cases. The effects of the foam lining material was not as significant to the model response as the helmet visor configurations, but in general, a lower density foam provided better load mitigation. In cases where there was no foam lining, pressure wave reflections in the air gap between the helmet and head were found to cause greater intracranial pressures in adjacent brain tissue, although the magnitudes of these increased pressures were generally lower than the incident compressive pressures caused by the initial wave impact.
Download or read book REVIEW OF LITERATURE AND REGULATION RELATION TO HEAD IMPACT TOLERANCE AND INJURY CRITERIA written by Robert L. Hess, Kathleen Weber, John W. Melvin and published by . This book was released on 1980 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Literature Survey of Airborne Vehicles Impacting with Water and Soil written by Gil Wittlin and published by . This book was released on 1992 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Using Finite Element Modeling to Analyze Injury Thresholds of Traumatic Brain Injury from written by Anna Marie Dulaney and published by . This book was released on 2018 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: A finite element model was developed for a range of human head-sUAS impacts to provide multiple case scenarios of impact severity at two response regions of interest: global and local. The hypothesis was that for certain impact scenarios, local response injuries of the brain (frontal, parietal, occipital, temporal lobes, and cerebellum) have a higher severity level compared to global response injury, the response at the Center of Gravity (CG) of the head. This study is the first one to predict and quantify the influence of impact parameters such as impact velocity, location, offset, and angle of impact to severity of injury. The findings show that an sUAS has the potential of causing minimal harm under certain impact scenarios, while other scenarios cause fatal injuries. Additionally, results indicate that the human head’s global response as a less viable response region of interest when measuring injury severity for clinical diagnosis. It is hoped that the results from this research can be useful to assist decision making for treatments and may offer different perspectives in sUAS designs or operation environments.
Download or read book Detection of Malingering during Head Injury Litigation written by Arthur MacNeill Horton, Jr. and published by Springer Nature. This book was released on 2021-07-22 with total page 366 pages. Available in PDF, EPUB and Kindle. Book excerpt: Expanding both the conceptual and clinical knowledge base on the subject, the Third Edition of Detection of Malingering during Head Injury Litigation offers the latest detection tools and techniques for veteran and novice alike. Increased public awareness of traumatic brain injuries has fueled a number of significant developments: on the one hand, more funding and more research related to these injuries and their resulting deficits; on the other, the possibility of higher stakes in personal injury suits—and more reasons for individuals to feign injury. As in its earlier editions, this practical revision demonstrates how to combine clinical expertise, carefully-gathered data, and the use of actuarial models as well as common sense in making sound evaluations and reducing ambiguous results. The book navigates the reader through the many caveats that come with the job, beginning with the scenario that an individual may be malingering despite having an actual brain injury. Among the updated features: Specific chapters on malingering on the Word Memory Test (WMT), Test of Malingered Memory (TOMM) MMPI-2, MMPI-RF and MMPI-3; Detailed information regarding performance on performance validity tests in the domain of executive functioning and memory, Guidelines for explaining performance and symptom validity testing to the trier of fact; Chapters on mild TBI in children in head injury litigation, cultural concerns and ethical issues in the context of head injury litigation.
