Body Armor Research Articles

COMPARATIVE ANALYSIS OF THE EFFECTIVENESS OF INDIVIDUAL BALLISTIC PROTECTION MEANS USED IN THE RUSSO-UKRAINIAN WAR

The present scientific paper presents a comparative analysis of the different types of individual ballistic protection devices, particularly focusing on body armor used in the high-intensity conflict between Russia and Ukraine. With the advancement of technologies and the introduction of new tactics in modern conflicts, losses of personnel significantly increased. The use of effective individual ballistic protection devices substantially reduces these losses. The report examines the following parameters to compare different types of body armor: class of ballistic protection, weight, protective area, and comfort in use. To conduct the analysis, available literary sources, military reports, and feedback from the personnel of the countries involved in the conflict were studied.

Effect of Material and Structure of Ultra-High-Molecular-Weight Polyethylene Body Armor on Ballistic Limit Velocity: Numerical Simulation.

The material properties and structural characteristics of ballistic composites are crucial to their ballistic performance. A numerical model of a 1.1 g FSP penetrating a UHMWPE target plate was established in this paper. The numerical results show that the failure process of the body armor target plate primarily involves shear failure, interlayer delamination, and tensile failure. Based on this, further research was conducted on the influence of material properties and structural characteristics on the ballistic limit velocity of the UHMWPE armor plate. Furthermore, the study evaluates the effects of elastic modulus, tensile strength, shear strength, number of layers, and interlayer strength on the ballistic limit velocity of UHMWPE body armor. The findings reveal that the ballistic limit velocity is most sensitive to changes in shear strength, with variation rates ranging from -18% to +11%, showing an approximate positive correlation, while the elastic modulus has the smallest impact on ballistic limit velocity, with variation rates ranging from -2% to +4%. Additionally, appropriate interlayer strength can improve the ballistic limit velocity of the body armor to a certain extent. This study provides theoretical methods and recommendations for optimizing anti-penetration performance of UHMWPE body armor.

Armour in Medieval India. Medieval Indian Armour, Hoysaḷa Representation, Wider Documentation and Later Reality

Armour is very rarely shown in the non-Islamic art of medieval India after appearing, albeit infrequently, in the Indian art of earlier centuries. Subsequently, the representation of armour would become significantly more common. Nevertheless, there are exceptions, notably on temple carvings and carved vīragal hero or memorial stones from what had been the Hoysaḷa kingdom in the southern Deccan region. This article seeks to interpret these carvings, to identify the reality of the armour shown and to explain its socio-political context. Potential links are drawn between such carved representations and the terminology of armour as used in medieval India. The article concludes by looking at the possible survival of medieval armour technology and styles in the continued use of textile-based armours in southern India into and beyond the early modern era.

Composites in Ballistic Applications Focused on Ballistic Vests—A Review

The development of ballistic materials has improved very rapidly in the last few years. Body armor plays an important role in protecting individuals during military threats. Body armor can be divided into hard and soft variants depending on the trade-offs between protection levels and wearer agility. Current research aims to optimize strength-to-weight ratios by using different combinations of synthetic or natural fibers or their combinations to achieve increasingly demanding requirements for ballistic materials. Moreover, it examines the various types of fibers utilized in the construction of body armor, ranging from traditional materials like metal and ceramic to synthetic and natural fibers. This paper discusses ongoing research efforts aimed at further enhancing the performance of these materials, such as the incorporation of modified natural fibers into advanced composite systems. The review provides a comprehensive analysis of the current state of the materials utilized in ballistic protection.

Shock wave damage from the ventral side in primary blast injury: An experimental study in pigs

Aim/PurposeThis study aimed to apply a shock wave from the ventral side of a pig and examine its effect to use the results for new body armor production for humans. MethodsSeven male hybrid pigs were used. Each pig was placed under general anesthesia on the experimental table in a blast tube to expose the left lateral position from the front chest area, and shock waves generated by compressed air at 3.0 MPa were applied. We examined changes in vital signs and arterial blood gas in the hyper-acute phase and computed tomography (CT) images, and autopsies were performed for organ damage after 3 h of observation. Pathological examination was performed for lung damage, which is considered a characteristic of shock wave injury. ResultsAll seven pigs survived. Respiratory arrest occurred in two pigs; however, spontaneous breathing resumed promptly afterward. Hypotension occurred at a frequency of 4. No bradycardia or cardiac arrest was observed in any pig. In the arterial blood gas analysis before and immediately after shock wave exposure and 1 hour later, PaO2 decreased immediately but tended to improve thereafter. CT revealed pulmonary contusions and multiple bulla-like lesions on the surface of the lungs. An autopsy showed lung injury in all pigs, particularly in five cases with bulla-like lesions of various sizes on the lung surface across all lobes. Pathological findings showed visceral pleural detachment with elastic fibers from the lung parenchyma, and the cavity lesion on the lung surface comprised bullae. The degree of intra-abdominal hemorrhage varied; however, all but one case showed splenic injury. ConclusionNone of the pigs exposed to shock waves from the ventral side died; however, most showed multiple bullae on the lung surface with lung contusion and splenic injury, which may have been greater than those exposed from the dorsal side. This may be due to the direct impact of the shock wave proceeding from the epigastrium and subcostal region, which are not protected by the skeletal structure of the thorax. These characteristics should be considered when producing new body armor for humans to protect the body from shock waves.

Nasal injuries in amateur male boxers before and after the 2013 rule change by the International Boxing Association removing the protective headgear

Boxing is a popular combat sport in which participants frequently experience head trauma. The neurological impact of boxing has been widely discussed, but the impact on the bone and soft tissue of the head has been less investigated. For this study, a national emergency department database was used to investigate the impact of a 2013 rule change — removing the requirement for amateurs to wear head protection — on the frequency and type of facial injuries sustained by amateur boxers. Over the study period (2006–2021) there were 11 760 injuries, with 6261 occurring before the change and 5499 occurring after (p < 0.001). The number of contusions, fractures, hematomas, and hemorrhages all significantly decreased after the rule change, while the number of lacerations did not. Additionally, the number of septal deviations increased from 16 to 97 (p < 0.001). According to age-group-specific analysis, injuries decreased in both the 0–17 and 24–29 cohorts, but increased in the 18–23 group. The results suggest that the rule change may have had a protective effect on the risk of craniofacial trauma in amateur boxers, potentially due to increased risk-averse behavior by the boxers, who may feel less protected during sparring because of the lack of head protection.

Research on high-velocity ballistic impact of para-aramid sateen fabric with ZnO nanorods oriented to the development of soft body armor

This study introduces an innovative approach of utilizing ZnO nanorod growing technology to the sateen fabric in order to improve its ballistic performance. Through SEM, FTIR, XRD and XPS analyses, ZnO nanorods with majority length of 1000–1500 nm and fineness of 200–600 nm have been deposited on the surface of sateen fabric surface Compared the fabric with ZnO nanorods (S-11-Nrs) with its neat counterpart, the mechanical properties of S-11-Nrs are increased, especially the inter-filament friction and fabric tensile breaking strength. However, in the impact process, the number of filaments involved in the impact is reduced and the filaments are mainly failure by the shear action of the bullets. Due to these positive and negative effects, the energy absorption of S-11-Nrs displays inferior ballistic energy absorption. Nevertheless, at lower areal density, in the non-perforation test, S-11-Nrs presents less BFS and shows better resistance to the consecutive shotting process compared with the neat fabric. The reason is that the increase of inter-filament friction limits the movement of filaments and thus results in less BFS. In addition, the flexibility, air permeability and moisture permeability are still kept. This research offers valuable insights for the design and development of comfortable soft body armor.

Emergency Operable Traumatic Pulmonary Injury at a Level 1 Trauma Center: A Retrospective Descriptive Study

ABSTRACT Introduction Despite the use of body armor, emergency operable pulmonary trauma (EOPT) remains a major cause of battlefield morbidity and mortality. While EOPT during military conflicts has some features that distinguish it from EOPT in civilian settings, the 2 occurrences demonstrate overall parallel findings related to presentation, management, and outcome. The goals of the present study were to provide a descriptive analysis of the nature of EOPT and its management at a level 1 trauma center and to determine the associations between EOPT patient demographics and/or patient management and outcome in order to better understand battlefield EOPT. Materials and Methods This is a retrospective, descriptive analysis of EOPT at a level 1 trauma center during a recent 9-year period (2012–2020). The Oregon Health &amp; Science University Trauma Registry was searched, and 106 patients met inclusion criteria for the study. Patients with primary cardiac trauma were excluded. Individual electronic medical records were reviewed to obtain descriptive data, and associations were evaluated for statistical significance. Results In-hospital mortality in this cohort was 17.0%. The most common pulmonary injury associated with EOPT was unilateral diaphragmatic laceration (62.3%), and the most common single operation performed for EOPT was a laparotomy (71.7%) often involving diaphragmatic repair. In the remaining instances of EOPT, a thoracotomy (11.3%), a thoracotomy and a laparotomy (10.4%), or another surgery (6.6%) occurred. The primary indication for EOPT surgery was uncontrolled hemorrhage, and one-third of patients received massive transfusion. One-lung ventilation (OLV) was infrequently employed (8.5%). When OLV was used, it was equally likely to involve a single-lumen endotracheal tube (SLETT) with mainstem bronchus insertion, a SLETT with a bronchial blocker, or a double-lumen endotracheal tube. Time from EOPT to operating room arrival was inversely related to in-hospital mortality. Also, both initial in-hospital endotracheal intubation and low injury severity score were strongly associated with survival in the population studied. Conclusions The most common indication for EOPT surgery was uncontrolled hemorrhage. The most frequent operation performed for this EOPT cohort was a laparotomy for diaphragmatic repair. A total of 91.5% of EOPT surgery was performed without OLV, an unexpected finding. When OLV occurred, it was equally likely to involve an SLETT with mainstem bronchus insertion, an SLETT with bronchial blocker, or a double-lumen endotracheal tube. The most common indication for OLV was surgical exposure. More extensive injury (expressed as an injury severity score), preadmission endotracheal intubation, and a shorter time from EOPT to operating room arrival were associated with increased odds ratios for mortality. A better understanding of the nature of EOPT at a civilian level 1 trauma center can serve to identify conditions that are associated with more favorable outcomes for EOPT under battlefield conditions and thereby assist in both management decisions and to help prognosticate and triage severely injured patients in that setting.

Bio-inspired helicoidal hemp/basalt/polyurethane rubber bio-composites: Experimental, numerical and analytical ballistic impact study with residual velocity prediction using artificial neural network

Recent body armour trends emphasize mobility, flexibility, and cost reduction while maintaining ballistic effectiveness through the use of natural fiber composite. This study evaluates the ballistic impact performance of soft and hard armor using experimental, analytical, numerical, and machine learning methods. We developed a soft armor bio-composite using monolithic, hybrid, and helicoidal structured Hemp (H)/Basalt (B)/Polyurethane (PU) rubber and tested its V50 ballistic limit according to Millitary-Standred-662 F. For hard armour, a multi-layer armor system (MAS) consisting of Al2O3/SiC ceramic, intermediate soft armour bio-composites, and an Aluminum (Al)-5052 plate backing was tested with armour-piercing bullets as per National Institute of Justice (NIJ)-0101.06 standards (Level IV). Soft armor performance was evaluated using macro-homogeneous finite element (FE), the Ipson-Retch analytical, and an Artificial Neural Network (ANN) regression model. Results showed minimal discrepancies from experimental data, with differences of 13.33 %, 12.08 %, and 8.08 % in V50 ballistic limit. The mechanical and thermal behaviors of bio-composites were assessed using un-notched Charpy, FTIR, and TGA methods. Helicoidal laminates improved Charpy toughness by 9.44 %, 19.30 %, and 40.28 % compared to hybrid and monolithic ([H]15 and [H]10) laminates, and exhibited lower weight reduction at high degradation temperature of 395.76 ℃. Helicoidal laminates increased V50 ballistic performance by 155.80 %, 76.22 %, and 16.61 % compared to [H]10, [H]15, and hybrid laminates, respectively. Due to spiral load distribution reduces stress concentration and enhanced the damage resistance of the laminate. Stand-alone soft armor demonstrates crater formation and radial cracks (petaling) due to fiber wedging and the shearing effect of a bullet. In conclusion, MAS revels a maximum back face deformation (BFD) of 18.06 mm. Al2O3/Helicoidal/Al-plate MAS reduced weight and cost by 69.21 %, and 233.72 % compared to Kevlar™-based MAS, promoting sustainable, lightweight, economical designs. Due to its higher fracture toughness and lower density, SiC ceramic in MAS provides lower trauma and further reduced weight compared to Al2O3 ceramic.

Facile armour production from cocoon waste by a cold-pressing process

Utilising cocoon waste as reinforcement in composites offers a cost-effective alternative for soft body armour production. Cocoon waste, including damaged or uncoiled cocoons and those with pupae, is recognised as an eco-friendly choice. This study aims to develop and assess the incorporation of varying amounts of cocoon waste as reinforcement in epoxy resin matrix composites through the cold-pressing process. The cocoon waste content in the composite specimens ranged from 0 to 40 wt%. Tensile testing and ballistic impact testing were conducted to evaluate specimen performance. The cocoon waste composite plate exhibited a maximum tensile strength of 62.21 MPa at 30 wt%, slightly surpassing that of woven hemp. These findings indicate the advantageous reinforcement attributes of cocoon waste. However, a limitation was identified: bullets fully penetrated the composite plate. To address this, ultra-high-molecular-weight polyethylene was incorporated into cocoon waste composites, resulting in enhanced tensile strength (107.36 MPa) and complete bullet penetration prevention. These outcomes position the study as a promising avenue for developing body armour plates meeting the stringent level II certification standards set by the National Institute of Justice.

Risk Factors Affecting The Incident of Malaria in The Working Area of The Malaimsimsa Public Health Center Sorong City

Background: Malaria is an infectious disease caused by Plasmodium sp, a single-celled living creature that belongs to the group of the genus Protozoa which is parasitic. The purpose of this study was to determine the influence of environmental factors and behavioral factors on the incidence of malaria in the working area of the Malaimsimsa Community Health Center, Sorong City.Methods: This research is an observational study using a case-control study . The case group in this study included people with malaria as indicated by positive malaria blood test results. Examination of malaria is carried out by means of microscopic examination by making thick and thin blood preparations, stained using Giemsa stain, then identified using a microscope. The control group includes people who are not sick with negative blood test results.Result: The results of this study indicate that all malaria infections that occur are caused by infection with the type of Plasmodium vivax. The risk factors that influence the incidence of malaria are behavioral factors, namely the use of body armor and the use of insect repellent. While the risk factors that do not affect the incidence of malaria are the presence of puddles, temperature and use of mosquito nets.Conclusion : From the results of this study it can be concluded that the factors of stagnant water, temperature and use of mosquito nets are not related to the incidence of malaria, on the contrary the use of body armor and the use of insect repellent have a relationship with the incidence of malaria.

Artificial Spider Silk Materials: From Molecular Design, Mesoscopic Assembly, to Macroscopic Performances

AbstractSpider silk is one of the strongest and toughest fibrous materials available in nature. Its superior properties make it a good candidate for applications in various fields ranging from protective body armor to scaffolds for medical implants. However, harvesting a substantial amount of natural spider silk remains challenging because spiders cannot be easily bred. With the development of synthetic biology and its integration with materials science, considerable research has been directed toward engineering and production of synthetic spider silk materials. Here the study overviews general strategies on molecular design, mesoscopic assembly, and macroscopic regulation of artificial spider silk materials. The insights into the correlation between silk protein sequences, mesoscopic assemblies, and macroscopic material properties are provided for guiding de novo design and engineering of next‐generation spider silk materials. This review also emphasizes the challenges and future perspectives for advancing the translational research on these designer functional materials for diverse applications.

Behind Armor Blunt Trauma: Liver Injuries Using a Live Animal Model.

While the 44-mm clay penetration criterion was developed in the 1970s for soft body armor applications, and the researchers acknowledged the need to conduct additional tests, the same behind the armor blunt trauma displacement limit is used for both soft and hard body armor evaluations and design considerations. Because the human thoraco-abdominal contents are heterogeneous, have different skeletal coverage, and have different functional requirements, the same level of penetration limit does not imply the same level of protection. It is important to determine the regional responses of different thoraco-abdominal organs to better describe human tolerance and improve the current behind armor blunt trauma standard. The purpose of this study was to report on the methods, procedures, and data collected from swine. Live swine tests were conducted after obtaining approvals from the local institution and the Army Care and Use Review Office of the U.S. Department of Defense. Trachea tubes and an intravenous line were introduced before administering anesthesia. Pressure transducers were inserted into the lungs and aorta. An indenter simulating the backface deformation profiles produced by body armor from military-relevant ballistics to human cadavers was used to deliver impact loading to the liver region. A triaxial accelerometer was included in the indenter design. The animals were monitored for 6 hours, necropsies were performed, and injuries were identified. Biomechanical data of the energy, velocity, deflection, viscous criterion, force, and impulse variables were obtained for each test. Peak accelerations, velocities, deflections, forces, impulse, and energies ranged from 897 to 5,808 g, 21 to 59 m/s, 1.96 to 8.87 cm, 2.3 to 13.1 kN, 1.1 to 7.1 Ns, and 58 to 387 J, respectively. The peak viscous criterion ranged from 0.8 to 5.8 m/s. All animals survived the 6-hour survival period. Three animals responded with liver lacerations while the remaining 4 did not have any injuries. The experimental design based on parallel tests with whole body human cadavers and cadaver swine was found to be successful in delivering controlled impacts to the liver region of live swine and reproducing liver injuries. Previously used biomechanical measures as potential candidates for injury criteria development were obtained. Using this proven model, tests with additional samples are needed to develop injury risk curves for liver impacts and obtain regional (liver) injury criteria.

Heat Flow Estimation in Polymer Films during Orientational Drawing at the Local Heater.

The optimization of the process of polymer film orientational drawing using the local heater was investigated. One of the problems with this technology is that the strength of the resulting fibers differs significantly from the theoretical estimates. It is assumed that one of the reasons is related to the peculiarity of this technology, when at the point of drawing the film is heated only on one side, which creates a temperature difference between the sides of the film in contact with the heater and the non-contact sides of the film in the air. Estimates show that even a small temperature difference of just 1 °C between these surfaces leads to a significant difference in the rate of plastic deformation of the corresponding near-surface layers. As a consequence, during hardening, in the stretching region, tensile stress is concentrated on the "cold" side of the film, and this effect can presumably lead to the generation of more defects overthere. It has been suggested that defects arising during first stage of hardening, namely, neck formation, can serve as a trigger for the formation of defects such as kink bands on the "cold" side with further orientational strengthening due to plastic deformation of the resulting fibrillar structure, at the boundaries of which microcracks are formed, leading to rupture of the oriented sample. The numerical calculation of heat propagation due to heat conduction in the film from the local surface of the heater is carried out and the temperature distribution along the thickness and width of the film during drawing is found. The temperature difference in the heated layer of the film between the contact and non-contact sides with the heater was calculated depending on the thickness of the film and the speed of its movement along the heater. It was found that the most homogeneous temperature distribution over the film thickness, which is required, by default, for the synchronous transformation of the unoriented initial folded lamellar structure into a fibrillar structure, is observed only for films with a thickness of less than 50 μm. The calculation allows us to scientifically justify the choice of orientation drawing speed and optimal thickness of the oriented polymer film, which is extremely important, for example, for obtaining super-strong and high-modulus UHMWPE filaments used in products for various purposes: from body armor to sports equipment and bioimplants.

Women are not small men: the UK’s new, comprehensive Tri-Service Anthropometry survey

Human Factors Engineers need accurate anthropometric data to design military equipment that is safe, comfortable and enables performance under extreme operational conditions and in the most severe environments. The Ministry of Defence (MOD) acknowledges that its current anthropometry dataset is becoming increasingly unrepresentative of today’s Armed Forces personnel, particularly women and minority ethnic groups. To address this issue, MOD has launched a new, comprehensive anthropometry survey. Whilst this survey has the potential to benefit the design of all new military equipment and clothing, the principal driver for the study is the development of new body armour for the UK’s Armed Forces personnel. This paper describes the requirements underpinning this survey, with a focus on body armour; the planned solution; and the results of Pilot Studies that have tested the robustness, reliability and accuracy of the measurement technologies and procedures. The work reported in this paper has been funded by the MOD’s Defence Innovation Unit. Practitioner statement: The UK Ministry of Defence has launched a new, comprehensive anthropometry survey, in acknowledgement of the fact that its current anthropometry dataset is becoming increasingly unrepresentative of today’s Armed Forces personnel. This paper describes the requirements underpinning the survey, the planned solution and the result of Pilot Studies.

Urologic Trauma Management for Military Providers.

Genitourinary (GU) trauma resulting from combat and the treatment of these injuries is an inadequately explored subject. While historically accounting for 2 to 5% of combat-related injuries, GU-related injuries escalated considerably during U.S. involvements in Iraq and Afghanistan due to improvised explosive devices (IEDs). Advanced body armor increased survivability while altering injury patterns, with a shift toward bladder and external genitalia injuries. Forward-deployed surgeons and military medics manage treatment, with Role 2 facilities addressing damage control resuscitation and surgery, including GU-specific procedures. The review aims to provide an overview of GU trauma and enhance medical readiness for battlefield scenarios. This review examined urologic trauma management in combat, searching PubMed, Cochrane Central, Scopus, and Web of Science databases with search terms "wounds" OR "injuries" OR "hemorrhage" AND "trauma" AND "penile" OR "genital" AND "combat." Records were then screened for inclusion of combat-related urologic trauma in conflicts after 2001 and which were English-based publications. No limits based on year of publication, study design, or additional patient-specific demographics were implemented in this review. Ultimately, 33 articles that met the inclusion criteria were included. Included texts were narrowed to focus on the management of renal injuries, ureteral trauma, bladder injuries, penile amputations, urethral injuries, testicular trauma, Central nervous system (CNS) injuries, and female GU injuries. In modern conflicts, treatment of GU trauma at the point of injury should be secondary to Advanced Trauma Life Support (ATLS) care in addition to competing non-medical priorities. This review highlights the increasing severity of GU trauma due to explosive use, especially dismounted IEDs. Concealed morbidity and fertility issues underscore the importance of protection measures. Military medics play a crucial role in evaluating and managing GU injuries. Adherence to tactical guidelines and trained personnel is vital for effective management, and GU trauma's integration into broader polytrauma care is essential. Adequate preparation should address challenges for deploying health care providers, prioritizing lifesaving and quality-of-life care for casualties affected by GU injuries.

Fabrication and structural characterisation of ZrC-W cermet by spark plasma sintering: Application in ballistical projection

This paper describes the effect of addition of tungesten (W) when was introduced into ZrC composite forming ceramic metal-composite (MMC) and (FGMS) to improve the fracture toughness (KIC) and hardeness (Hv) of the composite ceramic-metal. ZrC and ZrC with addition of 20 % of tungesten (ZrC-W) were prepared by vacuum sintering FAST-SPS-FCT technology at the temperatures in the range of 1700–1800 °C for 400 s under pressure of 50 Mpa. Microtructural properties were investigated by X-ray diffraction and energy-dispersive spectrometry in addition scanning electron miroscopy. The investigations shows that the phase separation of the as-sintered ZrC and ZrC-20 wt%W into two phases: ZrC (dark) and (C)W (bright) indicating that the as-sintered (ZrC)W was thoroughly decomposed in tree phases ZrC, W2C and WC. The effect of the W is already illustrated. X-ray diffraction and energy-dispersive spectrometry results indicate that bright grains are W, (W)C and dark ZrC solid solution. The relative density increases with the reinforcement by W into ZrC. Fully dense ZrC and ZrC-20 vol% W ceramic metal-composite with a relative density of more than 98.8 % were obtained. The Vickers hardennes (HV), fracture toughness (KIC) and Raman spectroscopy will be performed in the near future. In addition, ballistic performance (dynamic properties by projectil persing resistance) . A finite element simulation will used to optimise the vol% W addition to obtain better mechanical properties and ballistical performance. The Analyzer of the termo-mechanical evolution within the volume of ZrC and ZrC-W specimens subjected to FAST-SPS-FCT platform (thermo-mechanical modeling under ABAQUS). Also, the ballistic performance will be evaluated using the Rosenberg model and compared with the experimental results in order to better understand the dynamic shock behavior of ceramic metal-composite (ZrC and ZrC-W) by the projectile that to be applied for body armor.

Virtual fit assessment of U.S. army body armor using NASA spacesuit techniques

Fit and accommodation are critical design goals for a body armor system to maximize Soldiers’ protection, comfort, mobility, and performance. The aim of this study is to assess fit and accommodation of body armor plates for the US Army. A virtual fit assessment technique, developed, validated, and deployed by NASA for spacesuit design, was adopted for this work. Specifically, 3D manikins of the Soldier population were overlaid virtually with geometrically similar surrogates of the armor plates. Trained subject matter experts with the US Army and NASA manually assessed the fit of the armor plates to manikins using a computer visualization tool and selected the appropriate plate size and position. A prediction model was built from the assessment data to predict the plate size from an arbitrary body shape and the resultant patterns of body-to-plate contact were quantified. The outcome indicated a unique trend of the plate sizes covarying with anthropometry. More pronouncedly, when the overlap between the body tissue and armor plate was quantified, female Soldiers are likely to experience a 25 times larger body-to-plate contact volume and 6.5 times larger contact depth than males on average, due to sex-based anthropometric differences. Overall, the prediction model and contact patterns provided key metrics for virtual body armor fit assessments, of which the locations, patterns, and magnitudes can help to improve sizing and fit of body armor systems, as previously demonstrated for NASA spacesuit design.

A new ankylosaurian osteoderm from the Middle Jurassic Oxford Clay Formation, United Kingdom

Ankylosaurs are a characteristic group of dinosaurs recognized by their extensive coverings of dermal bony armour, known as osteoderms, across their bodies. The Oxford Clay Formation (Callovian–Oxfordian, Middle Jurassic) in the UK is important for understanding early ankylosaur evolution as it contains some of the earliest known ankylosaur material, including a cranial osteoderm from the basal-most ankylosaur Sarcolestes (and probable postcranial osteoderms). Here, we describe an isolated osteoderm from the Oxford Clay of Peterborough that exhibits a different morphology to other osteoderms from this formation. The specimen, although incomplete along its transverse axis, measures 52.7 mm by 41 mm. The osteoderm is subrectangular with a concave ventral surface and a low, rounded keel on its dorsal surface that protrudes beyond the posterior margin of the specimen base. This morphology is superficially more similar to the thoracic osteoderms of more derived Cretaceous ankylosaurs from North America (e.g. Borealopelta ), than to Sarcolestes and other Jurassic ankylosaurs (e.g. Dracopelta , Mymoorapelta , Tianchisaurus ), but could represent a currently unknown Sarcolestes morphology. Although its isolated nature prevents reliable identification of the taxon and the body part to which it belonged, the osteoderm nevertheless indicates a larger morphological diversity in the body armour of the earliest ankylosaurs than currently appreciated.

Analysis of Ballistic Capability in Making Bulletproof Multilayers Using Woven Ramie Fiber, Hardfacing Metal with Epoxy Matrix for Bulletproof Vests

Bulletproof material in level III bulletproof vests must be created using hard and soft materials to prevent bullet penetration. Kevlar and SiC + PE are imported materials used as armor in bulletproof vests. The use of Kevlar and SiC is very dependent on foreign sources with high prices. An innovation was carried out by making bulletproof material using cheaper multilayer methods involving metal from hardfacing welding as a hard layer and ramie fiber as a soft layer with an epoxy matrix. To see the level of penetration and surface morphology structure in the specimens, 9 variations were made: 3 layers of hardfacing welding and 3 epoxy volume fractions (40%, 45%, 50%). Ballistic test using NIJ 0101.06 level III standards with AK-47 of 7.62 mm x 39 mm bullets and the morphology of bulletproof multilayer material after impact was observed using SEM. The results showed all specimens failed to withstand bullet penetration at a distance of 15 meters. Meanwhile, at 50 meters, the S2-C specimen with a 60% epoxy volume fraction was able to withstand bullet penetration with a BFS value of 25.85 mm. This value is &lt; 44 mm; thus, it complies with the NIJ 0101.06 body armor standard. According to SEM, most of the failures occurred because the resulting adhesion force was weak. It was necessary to add reinforcing material so that the adhesion force between the metal, ramie fiber, and adhesive increases; the materials must also have very light density to prevent the effectiveness reduction of the multilayer.