Academic literature on the topic 'Enhanced Combat Helmet'

This study demonstrates the orientation and the "shape factor" have pronounced effects on the development of the localized pressure fields inside of the helmet. We used anatomically accurate headform to evaluate four modern combat helmets under blast loading conditions in the shock tube. The Advanced Combat Helmet (ACH) is used to capture the effect of the orientation on pressure under the helmet. The three modern combat helmets: Enhanced Combat Helmet (ECH), Ops-Core, and Airframe, were tested in frontal orientation to determine the effect of helmet geometry. Using the unhelmeted headform data as a reference, we characterized pressure distribution inside each helmet and identified pressure focal points. The nature of these localized “hot spots” is different than the elevated pressure in the parietal region of the headform under the helmet widely recognized as the under-wash effect also observed in our tests. It is the first experimental study which indicates that the helmet presence increased the pressure experienced by the eyes and the forehead (glabella). Pressure fingerprinting using an array of sensors combined with the application of principle component analysis (PCA) helped elucidate the subtle differences between helmets.

With the evolution of modern warfare, there is a constant demand for enhanced soldier protection. The research efforts presented in this paper focus on improving the ballistic performance of composite combat helmets through the control of fiber orientations, reduction of seam density, and preservation of long fiber lengths. To accomplish these objectives, near-net-shape preforming is explored as an alternative method to the traditional cut and dart techniques used in the manufacture of combat helmets. An overview of current fabrication procedures is provided in addition to a discussion of the material selection and preform processing technique. Forming trials are conducted on Dyneema® HB80, a cross-ply thermoplastic lamina, using a laboratory deep-draw setup to explore the effects of processing parameters on the quality of the formed part. Undesirable wrinkling that manifests during deep-drawing of the material is found to be most effectively mitigated through the use of sufficient binder pressure. Furthermore, it is demonstrated that a loose ply stack up is more amenable to the production of high-quality preforms than a preconsolidated charge of material.

ABSTRACT Introduction The Advanced Combat Helmet (ACH) military specification (mil-spec) provides blunt impact acceleration criteria that must be met before use by the U.S. warfighter. The specification, which requires a helmeted magnesium Department of Transportation (DOT) headform to be dropped onto a steel hemispherical target, results in a translational headform impact response. Relative to translations, rotations of the head generate higher brain tissue strains. Excessive strain has been implicated as a mechanical stimulus leading to traumatic brain injury (TBI). We hypothesized that the linear constrained drop test method of the ACH specification underreports the potential for TBI. Materials and Methods To establish a baseline of translational acceleration time histories, we conducted linear constrained drop tests based on the ACH specification and then performed simulations of the same to verify agreement between experiment and simulation. We then produced a high-fidelity human head digital twin and verified that biological tissue responses matched experimental results. Next, we altered the ACH experimental configuration to use a helmeted Hybrid III headform, a freefall cradle, and an inclined anvil target. This new, modified configuration allowed both a translational and a rotational headform response. We applied this experimental rotation response to the skull of our human digital twin and compared brain deformation relative to the translational baseline. Results The modified configuration produced brain strains that were 4.3 times the brain strains from the linear constrained configuration. Conclusions We provide a scientific basis to motivate revision of the ACH mil-spec to include a rotational component, which would enhance the test’s relevance to TBI arising from severe head impacts.

The requirement to operate vehicles in low light and/or night environments whilst wearing night vision goggle (NVG) systems has become increasingly common during military operations. There is very limited research investigating injury risks associated with these systems during ground vehicle collisions. This study examined the injury risks associated with wearing the Australian Defence Force - Enhanced Combat Helmet (ECH) and NVG system, in frontal vehicle collisions. This project consisted of two components: (1) crash tests using a sled and (2) numerical simulations of impacts. Four dynamic sled tests were conducted using a 50th percentile, male, Hybrid III dummy positioned on a rigid seat. Frontal impact tests were performed at a 40 km/h change in velocity (*v) and 20 g deceleration. The test configurations were as follows: (a) Base; (no helmet or additional equipment); (b) ECH; and, (c) ECH and NVG. Condition (c) was carried out twice, to determine repeatability. The sled test protocols were reconstructed precisely with the numerical simulation package MADYMO and the simulations were shown to correlate well with the experimental results. Using this validated model, four parametric studies were undertaken to assess the influence of counterweights, seat cushion, seatbelt pre-tensioner, and the vehicle's *v and acceleration on injury risks. The study found that neck loads were within acceptable limits, with the exception of the neck extension moment, which was exceeded for all NVG conditions. Based on the parametric studies, no major improvements were observed in the neck extension moments with the use of counterweights or a seat cushion. In contrast the use of a seatbelt pre-tensioner was observed to decrease greatly this neck injury risk in certain scenarios. The study also identified that a *v of 15 km/h and peak acceleration of up to 14 g were required to keep the neck extension moment below the prescribed injury criteria. However, the high neck extension moment values may have been partially attributable to the stiff Hybrid III neck. This study identified a possible injury mechanism for soldiers using the ECH and NVG system during specific impact scenarios. The method applied in this project was designed to be repeatable.

Gender equality and information and communication technology are important in the achievement of the Millennium Development Goals (MDGs) in policy, planning, and practice. The 2000 Millennium Declaration of the United Nations (UN) formed an international agreement among member states to work toward the reduction of poverty and its effects by 2015 through eight Millennium Development Goals: 1. Eradicate extreme poverty and hunger 2. Achieve universal primary education 3. Promote gender equality and the empowerment of women 4. Reduce child and maternal mortality 5. Improve maternal health care 6. Combat HIV and AIDS, malaria, and other major diseases 7. Ensure environmental sustainability 8. Develop global partnership for development Progress toward gender equality and the empowerment of women is one goal that is important to achieving the others. Poverty, hunger, illiteracy, environmental threats, HIV and AIDS, and other health threats disproportionately affect the lives of women and their dependent children. Gender-sensitive ICT applications to education, health care, and local economies have helped communities progress toward the MDGs. ICT applications facilitate rural health-care workers’ access to medical expertise through phones and the Internet. Teachers expand learning resources through the Internet and satellite services, providing a greater knowledge base for learners. Small entrepreneurs with ICT access and training move their local business into world markets. ICT diffusion into world communication systems has been pervasive. Even some of the poorest economies in Africa show the fastest cell-phone growth, though Internet access and landline numbers are still low (International Telecommunications Union [ITU], 2003b). ICT access or a lack of it impacts participation, voice, and decision making in local, regional, and international communities. ICTs impact the systems that move or inhibit MDG progress. UN secretary general Kofi Annan explained the role of the MDGs in global affairs: Millennium Development Goals are too important to fail. For the international political system, they are the fulcrum on which development policy is based. For the billion-plus people living in extreme poverty, they represent the means to a productive life. For everyone on Earth, they are a linchpin to the quest for a more secure and peaceful world. (UN, 2005, p. 28) Annan also stressed the critical need for partnerships to facilitate technology training to enable information exchange and analysis (UN, 2005). ICT facilitates sharing lessons of success and failure, and progress evaluation of work in all the MDG target areas. Targets and indicators measuring progress were selected for all the MDGs. Gender equality and women’s empowerment are critical to the achievement of each other goal. Inadequate access to the basic human needs of clean water, food, education, health services, and environmental sustainability and the support of global partnership impacts great numbers of women. Therefore, the targets and indicators for Goal 3 address females in education, employment, and political participation. Progress toward the Goal 3 target to eliminate gender disparity in primary and secondary education, preferably by 2005, and in all levels of education no later than 2015, will be measured by the following indicators. • Ratio of girls to boys in primary, secondary, and tertiary education • Ratio of literate females to males who are 15- to 24-year-olds • Share of women in wage employment in the nonagricultural sector • Proportion of seats held by women in national parliaments (World Bank, 2003) Education is positively related to improved maternal and infant health, economic empowerment, and political participation (United Nations Development Program [UNDP], 2004; World Bank, 2003). Education systems in developing countries are beginning to offer or seek ways to provide ICT training as a basic skill and knowledge base. Proactive policy for gender equality in ICT access has not always accompanied the unprecedented ICT growth trend. Many civil-society representatives to the World Summit on the Information Society (WSIS) argue for ICT access to be considered a basic human right (Girard & Ó Soichrú, 2004; UN, 1948). ICT capability is considered a basic skill for education curriculum at tertiary, secondary, and even primary levels in developed regions. In developing regions, ICT access and capability are more limited but are still tightly woven into economic communication systems. ICTs minimize time and geography barriers. Two thirds of the world’s poor and illiterate are women (World Bank, 2003). Infant and maternal health are in chronic crisis for poor women. Where poverty is highest, HIV and AIDS are the largest and fastest growing health threat. Ninety-five percent of people living with HIV and AIDS are in developing countries, partly because of poor dissemination of information and medical treatment. Women are more vulnerable to infection than men. Culturally reinforced sexual practices have led to higher rates of HIV infection for women. Gender equality and the empowerment of women, starting with education, can help fight the spread of HIV, AIDS, and other major diseases. ICT can enhance health education through schools (World Bank). Some ICT developers, practitioners, and distributors have identified ways to incorporate gender inclusiveness into their policies and practice for problem-solving ICT applications toward each MDG target area. Yet ICT research, development, education, training, applications, and businesses remain male-dominated fields, with only the lesser skilled and salaried ICT labor force approaching gender equality. Successful integration of gender equality and ICT development policy has contributed to MDG progress through several projects in the developing regions. Notable examples are the South-African-based SchoolNet Africa and Bangladesh-based Grameen Bank Village Pay Phone. Both projects benefit from international public-private partnerships. These and similar models suggest the value and importance of linking gender equality and empowerment with global partnership for development, particularly in ICT. This article reports on developing efforts to coordinate the achievement of the MDGs with policy, plans, and practice for gender equality beyond the universal educational target, and with the expansion of ICT access and participation for women and men. The article examines the background and trends of MDG 3, to promote gender equality and the empowerment of women, with particular consideration of MDG 8, to develop global partnership for development, in ICT access and participation.

Abstract Computational modeling provides significant benefits in assessing the helmet performance and identifying promising helmet designs. We develop multi-fidelity computational tools, representative virtual human head and helmet system models to help the design of next generation combat helmet with improved protection against blunt impact. By integrating the fast-running articulated human with personal protective equipment (PPE) biodynamics model with the high-fidelity human head with combat helmet finite element (FE) model, the multi-fidelity approach can be used to efficiently investigate impact-related traumatic brain injury (TBI) in the real-world scenario. The FE model is used to capture the dynamics of the composite helmet shell, foam pad suspension, retention strap and head while the biodynamics model provides the proper kinematics and boundary conditions for the FE model. An orthotropic elasto-plastic material with damage model is employed for the helmet shell. Enhanced tetrahedral elements are used to model the nearly-incompressible tissues. The head with helmet and without helmet under a severe impact due to a fall caused by blast loading are simulated and compared. The resulting biomechanical responses of head acceleration, shear stresses and strains in brain and mechanical injury criterion as well as helmet energy absorption are used to characterize the performance of helmet system.

As a result of enhanced performance and mission requirements for Navy ships, ship design has dramatically increased the use of higher strength, lightweight steels and various local reinforcements, e.g., deck inserts, ring stiffeners, etc., in foundation designs to satisfy the design requirements for supporting machinery, consoles, and weapon systems among others. In additional to operational loading requirements, most of these foundations must also be designed to satisfy shock, vibration and other combat system requirements. While the same piece of equipment may be used in other ship contracts, the foundations are uniquely designed and require a separate analysis and drawing package. Computer modeling and Finite Element Analysis (FEA) have helped reduce the labor required to analyze foundations, but the high number of “unique” foundations as well as changes which necessitate a new analysis still create a large workload for engineers. This is further compounded by increased costs in production due to greater numbers of unique parts and materials that must be marked, stored, and retrieved later for fabrication. This goal of this project was to determine the cost-savings potential of leveraging past foundations work in designing, analyzing, and drawing foundations in the future. By the project’s conclusion Ingalls will have created a database for rapid access to previously-generated foundation information, the framework of which will be publicly available for all shipyards to populate with their own foundation information.

As a result of enhanced performance and mission requirements for Navy ships, ship design has dramatically increased the use of higher strength, lightweight steels and various local reinforcements, e.g., deck inserts, ring stiffeners, etc., in foundation designs to satisfy the design requirements for supporting machinery, consoles, and weapon systems among others. In additional to operational loading requirements, most of these foundations must also be designed to satisfy shock, vibration and other combat system requirements. While the same piece of equipment may be used in other ship contracts, the foundations are uniquely designed and require a separate analysis and drawing package. Computer modeling and Finite Element Analysis (FEA) have helped reduce the labor required to analyze foundations, but the high number of “unique” foundations as well as changes which necessitate a new analysis still create a large workload for engineers. This is further compounded by increased costs in production due to greater numbers of unique parts and materials that must be marked, stored, and retrieved later for fabrication. In this paper, we have developed a cost-savings potential of leveraging past foundations work in designing, analyzing, and drawing foundations in the future. The research team was able to estimate that, through a new design process that fully integrates previous foundations work, there is a potential for up to 40% savings on engineering foundations labor and up to 10% savings on production costs of foundations. The team also developed a blank “template” database that can be downloaded and customized to meet each shipyard’s needs for storing and accessing foundation design information.