Amphibious Assault Vehicle Research Articles

Analysis of Experience of Using Small UAVs in the Battlefield: Training Enhancement Perspectives

The article analyzes the experience of the State Border Guard Service units in fighting russian occupying forces inflicting the fire damage with the help of small UAVs and describes the ways to use the acquired experience to develop a training course for the border guard UAV operators. The authors state that nowadays, in the conditions of the of full-scale invasion to Ukraine, active using of unmanned aerial vehicles (hereinafter – UAVs) proved their ability to perform combat tasks, making them one of the new and effective types of weapons in modern military conflicts. It is impossible to imagine a contemporary army without UAVs, as today they perform multiple roles: adjusting artillery fire, pointing and tracking targets, transmitting intelligence information to the headquarters, delivering fire strikes, and most importantly – they can help save the lives of soldiers. Analysis of a year and a half term of full-scale invasion of Ukraine showed that the use of UAVs is several times more effective than the use of traditional types of weapons. In the first days of the war, a huge number of the russian battalion tactical groups (hereinafter – BTGs) were concentrated on the borders of Ukraine, and that significantly outweighed the forces and means of military formations of Ukraine. Analysis also proves that the main striking force during the offensive, according to the governing documents, were armored fighting vehicles, infantry fighting vehicles, amphibious assault vehicles, armored personnel carriers. And it was possible to stop enemy columns only with the help of artillery, aviation, and anti-tank missile systems. Therefore, in modern conditions, it is necessary to create fire damage to enemy armored vehicle groups with the help of attack UAVs of the border guard units. The article considers the effectiveness of such a unit, taking into account the tasks, organizational structure, forces and means necessary to respond to modern challenges and threats on the state border. The authors used the acquired experience of the Border Guard units to develop a training course for the UAV operators of the border guard units. The developers of the course took into account the combat experience and the best European practices in UAV operators training. The learning strategy of the course is based on a student-centred learning approach. It is designed to provide learners with theoretical knowledge and practical skills on the operators of the UAV crews deployed in border surveillance and combat operations. The course is divided in three phases: Independent Learning Phase (online), Contact Learning Phase (offline) and Experiential Learning Phase (at the border guard units).

Numerical Analysis on Dynamic Behavior Characteristics of an Amphibious Assault Vehicle during Water Entry

In the present study, the dynamic behavior characteristics of an amphibious assault vehicle during water entry were analyzed using STAR-CCM+, a commercial computational fluid dynamics(CFD) code. All computations were performed using an overset mesh system and a RANS based flow-solver coupled with dynamic fluid-body interaction(DFBI) solver for simulating three degrees of freedom motion. For numerical validation of the solver, a water entry simulation of inclined circular cylinder was conducted and it was compared between an existing experiment data and CFD results. The pitch angle variation and the trajectory of the circular cylinder during water entry shows good agreement with previous experimental and numerical studies. For the water entry simulations of the amphibious assault vehicle, the analysis of dynamic behaviors of the amphibious assault vehicle with different slope angles, submerged depths and initial velocities were conducted. It is confirmed that the steep slope angle increases the submerged volume of the amphibious assault vehicle, so the buoyancy acting on the vehicle is increased and the moved distance for the re-flotation is decreased. It is also revealed that the submerged volume is increased, bow-up phenomenon occur earlier.

행위자 기반 모델링을 이용한 유·무인 복합체계의 전투효과 분석

This study tried to suggest implications for effective team composition in the manned-unmanned teaming system by analyzing the effect of the combination of manned and unmanned platforms on the combat effect in the manned-unmanned teaming system. In this study, by changing the ratio of amphibious operation vehicles (KAAV), unmanned ground vehicles (UGV), and unmanned aerial vehicles (UAV), the combat survival rate was calculated in a standard operation scenario using AnyLogic, an agent-based modeling program. As a result of the analysis, it was confirmed that an appropriate combination is possible to optimize the combat efficiency of the unmanned weapon system, the unmanned aerial vehicle (UGV) and the unmanned aerial vehicle (UAV), compared to the use of the current manned amphibious assault vehicle (KAAV) alone. It is expected that the research results will be a reference for M&S analysis for each stage of weapon system acquisition and establish the operational concept of the manned-unmanned teaming system that will be promoted to foster the advanced science and technology forces pursued by Defense Innovation 4.0.

Software Design about Integrated Fault Diagnosis for the Propulsion System of the Tracked Amphibious Assault Vehicle

This paper describes the design of model-based fault diagnosis software to apply to the propulsion system in tracked amphibious assault vehicle which consists of an engine, a transmission, a cooling system, and two waterjets. This software includes specific functions to detect the failures regarding sensor malfunctions, mechanical malfunctions, control errors, and communication errors. This software generates the proper malfunction codes which are classified as the warning and caution. In order to validate the fault diagnosis software, the manual and automatic test are performed using the test program with 32 test cases. Test results show that the designed fault diagnosis software is reliable and effective for applying to the propulsion system.

Development Direction of Reliability-based ROK Amphibious Assault Vehicles

Development Direction of Reliability-based ROK Amphibious Assault Vehicles

Numerical Analysis on the Resistance and Propulsion Performances of High-Speed Amphibious Assault Vehicles

Numerical Analysis on the Resistance and Propulsion Performances of High-Speed Amphibious Assault Vehicles

상륙돌격장갑차의 수상항주 시 트림조절을 위한 수중익에 의한 저항 및 자세변화에 대한 실험적 연구

Amphibious assault vehicles have been used in the Marine Corps. In recent years, their ability to move faster is becoming one of the most important considerations. At high speeds, the vehicle tends to sink at the stern and sometimes the opposite occurs. Such dynamic trim plays a significant role in determining the vehicle's hydrodynamic performance. Furthermore, an excessive trim by stern upsets the viewing angle. We have thus considered a stern hydrofoil to reduce the dynamic trim of the amphibious assault vehicle. Laboratory-scale resistance tests were conducted in a towing tank at the Seoul National University (SNU). This study aims to make a preliminary assessment of the hydrodynamic performance of the vehicle with the stern hydrofoil and to investigate permissible speed range of the vehicle. The experimental results show that the stern hydrofoil can successfully achieve a reduction of both the dynamic trim and the hydrodynamic resistance at running speeds above 20 km/h.

Research on Core-Technology of Semi-Physical Maintenance Training System

For a long time, training work of army equipment maintenance crew mostly goes on real-equipment, which is organized by academies or relevant units later. In some extent, this kind of conventional maintenance ways decrease the efficiency and quality of weapon equipment maintenance. In face of more and more new equipment, it not only increases the difficulty of maintenance training but also brings a new challenge to conventional maintenance ways. Aiming at the lack of maintenance training ways of conventional land-battle equipment, we adopt new technology of virtual reality in recent years to create typical-type amphibious assault vehicle virtual maintenance training system, which provide new means for maintenance crew. This text is tend to analyze interactive desktop virtual maintenance training system, and then for instance, briefly introduce typical-type amphibious assault vehicle.

On the Design of Vehicular Electrically Small Antennas for NVIS Communications

Design of low-profile vehicular on-the-move (OTM) wideband high-frequency (HF) antennas with 24-kHz instantaneous bandwidth for near-vertical communications is discussed. It is shown that multiarming significantly reduces the minimum antenna height, whereas the two-arm configuration is a tradeoff between antenna complexity and performance. A procedure for determining the minimum antenna height when the tuner loss is considered as a design parameter is introduced. The design evolves from a state-of-the-art magnetic dipole to a wire two-arm half-loop antenna (HLA). The profile for the amphibious assault vehicle (AAV) mounted antenna is 0.65 m ( $\lambda/230$ at 2 MHz) for the parabolic shape and 0.50 m ( $\lambda/300$ ) for the rectangular shape two-arm half-loop. The length of antenna base is 4.8 m ( $\lambda/31$ ) and the width is 3.3 m ( $\lambda/45$ ). A simple two-element tuner is considered in the scope of the results validation, along with the impedance and directivity patterns measurements on scaled 1/500 models.

Prediction on Combat Effectiveness of Amphibious Assault Vehicles Based on Supporting-Vector Regression

In this paper, a predictive model has been established for the combat effectiveness of amphibious assault vehicles by the method of supporting-vector regression. It has a good fitting result after trained with the samples. Then this model is used to predict the combat effectiveness of the sample under evaluation. The SVR approach can convert the practical questions into the high-dimensional feature space through non-linear transfer, and construct the linear decision functions in the space to realize the original non-linear decision functions. This approach has its significance for the prediction of combat effectiveness of AAVs.

The Fault Diagnose of Advanced Amphibious Assault Vehicle Fan Pump Based on Principal Component Regression

The fan pump hydraulic system of amphibious assault vehicle is prone to fault , an pump leakage model is established by principal component regression. This new modeling strategy can effectively extract on the components which have a strong explanatory role of the dependent variable, it achieves regression modeling in multiple arguments correlation conditions, and allows the inclusion of all the original variables. This model get rid of drawback that the least squares regression can not effectively identify and eliminate the influence of the multiple relativity among factors.

Application of Support Vector Machine Regression in Failure Analysis of Fan Pump in Amphibious Assault Vehicles

Hydraulic motor is one of the elements with a high occurrence rate of failure in hydraulic system of amphibious assault vehicles. When the fan pump leakage reaches the limit value allowed, the fan pump should be renewed or overhauled. Through an analysis of the influencing factors that affect fan pump leakage of amphibious assault vehicles, this article establishes a support vector machine (SVM) regression model for fan pump leakage and gets a maximum relative error of 4% between the fitted value and the measured value of fan pump, which offers more reliable evidence for scientific determination of renewal period or overhaul period of fan pump.

Failure Diagnosis of Hydraulic Motor in Amphibious Assault Vehicles Based on Support Vector Machine (SVM)

Hydraulic motor is one of the elements with a high occurrence rate of failure in hydraulic system of amphibious assault vehicles. When the motor leakage reaches the limit value allowed, the motor should be renewed or overhauled. Through an analysis of the influencing factors that affect hydraulic motor leakage of amphibious assault vehicles, this article establishes a support vector regression model for motor leakage and gets a maximum relative error of 4.29% between the fitted value and the measured value of motor leakage, which offers more reliable evidence for scientific determination of renewal period or overhaul period of hydraulic motor

Application of Projection Pursuit Regression in the Fault Diagnose of Advanced Amphibious Assault Vehicle Hydraulic Motor Based on Applied Mechanics

The hydraulic motor of amphibious assault vehicle is one of the important output executive components of the hydraulic system whose performance has an important influence for the whole system. According to the high failure rate, fault detection and location problems of hydraulic system, this paper explore the relationship between the leakage of amphibious assault vehicle and each influential factor, establish the leakage predication model by projection pursuit regression method and get a better predicated effect. It has great significance for the fault diagnosis of hydraulic motor of amphibious assault vehicle.

Chronic traumatic encephalopathy in an Iraqi war veteran with posttraumatic stress disorder who committed suicide

Following his discovery of chronic traumatic encephalopathy (CTE) in football players in 2002, Dr. Bennet Omalu hypothesized that posttraumatic stress disorder (PTSD) in military veterans may belong to the CTE spectrum of diseases. The CTE surveillance at the Brain Injury Research Institute was therefore expanded to include deceased military veterans diagnosed with PTSD. The authors report the case of a 27-year-old United States Marine Corps (USMC) Iraqi war veteran, an amphibious assault vehicle crewman, who committed suicide by hanging after two deployments to Fallujah and Ramadi. He experienced combat and was exposed to mortar blasts and improvised explosive device blasts less than 50 m away. Following his second deployment he developed a progressive history of cognitive impairment, impaired memory, behavioral and mood disorders, and alcohol abuse. Neuropsychiatric assessment revealed a diagnosis of PTSD with hyperarousal (irritability and insomnia) and numbing. He committed suicide approximately 8 months after his honorable discharge from the USMC. His brain at autopsy appeared grossly unremarkable except for congestive brain swelling. There was no atrophy or remote focal traumatic brain injury such as contusional necrosis or hemorrhage. Histochemical and immunohistochemical brain tissue analysis revealed CTE changes comprising multifocal, neocortical, and subcortical neurofibrillary tangles and neuritic threads (ranging from none, to sparse, to frequent) with the skip phenomenon, accentuated in the depths of sulci and in the frontal cortex. The subcortical white matter showed mild rarefaction, sparse perivascular and neuropil infiltration by histiocytes, and mild fibrillary astrogliosis. Apolipoprotein E genotype was 3/4. The authors report this case as a sentinel case of CTE in an Iraqi war veteran diagnosed with PTSD to possibly stimulate new lines of thought and research in the possible pathoetiology and pathogenesis of PTSD in military veterans as part of the CTE spectrum of diseases, and as chronic sequelae and outcomes of repetitive traumatic brain injuries.

Design of a Model-Scale Air-Core Compulsator

A preliminary design scheme of a model-scale compulsator, which is the heart of the railgun pulse-power system, is provided in this paper. The model-scale air-core compulsator, which can provide considerable energy, power density, and energy density, is the best choice for pulse-power supply of a railgun system equipped to an amphibious assault vehicle. To allow rapid sizing of compulsator systems, it is necessary to present the main first-stage design process which can be used to design systems for advanced applications. Three main aspects during the design of a model-scale compulsator are necessarily presented in this paper: the simulation and calculations of air-core electromagnetic field; the evaluation of extremely high forces imposed during the discharge; and the choice of cooling method of the windings due to the large level of armature current and excitation current. The topology of the model-scale compulsator is chosen. The compulsator has no concrete compensation component, and the excitation winding does the excitation and compensation simultaneously. The design of the model-scale is based on research of a small-scale air-core principle prototype. The feasibility of the technique and machining is also demonstrated. In addition, the main auxiliary components, such as the high-temperature superconducting magnetic bearing and the high-speed brush slip-ring mechanism, are discussed according to the operating conditions.

Stress-Corrosion Cracking Susceptibility of Various Product Forms of Aluminum Alloy 2519

Aluminum alloy 2519 is the main structural alloy for the Advanced Amphibious Assault Vehicle (AAAV). A potential drawback to the use of 2519, particularly for an amphibious vehicle, is its susceptibility to corrosion. General corrosion, which is largely in the form of pitting, may reduce the effective life of the system, while stress-corrosion cracking (SCC) of any high strength aluminum alloy can lead to catastrophic failure. Therefore, an evaluation of the SCC susceptibility of various 2519 product forms was performed. Plate, extrusions, ring roll forgings, and weldments all exhibited excellent SCC resistance as measured by a series of standard ASTM tests. Multi-axis hand forgings were the only product forms that exhibited SCC susceptibility, and this susceptibility was remedied via the use of a specifically designed heat treatment. While all product forms passed the prescribed SCC tests, each exhibited a significant reduction in strength after simultaneous exposure to both stress and the saline corrosion environment. Such behavior was not apparent when the exposure was limited to the corrosion media alone. That is, while resistant to SCC, the load-bearing capacities of all products tested are somewhat degraded during concurrent exposure to stress and corrosive media by a mechanism that includes pitting. This article will discuss the effort that was conducted by the National Center for Excellence in Metalworking Technology (NCEMT) to evaluate the SCC susceptibility of 2519 in various product forms and tempers.

Continued testing of the cannon caliber electromagnetic gun system (CCEMG)

The cannon caliber electromagnetic gun system is based upon a compulsator driven 30 mm rapid fire railgun system. The objective of the program was to develop a compact, lightweight test bed capable of launching three, five round salvoes of 185 g integrated launch packages to 1.85 km/s at a firing rate of 5 Hz. Per contractual requirements, the pulse power system is also size compatible with the amphibious assault vehicle. The pulse power system was developed around a fourth generation air-core, 4-pole rotating armature, self-excited, compulsator design. Although the contract for this effort has expired, the system continues to be used in part to demonstrate compulsator driven railgun technology. This system has performed seven single shots using identical control settings for each shot, which is the first such experience using a compulsator driven railgun system. This paper describes the experimental set-up for the demonstrations and compares the generator, converter, gun switch, and launcher performances for each shot.

Laboratory testing of the pulse power system for the cannon caliber electromagnetic gun system (CCEMG)

The team of (prime contractor) United Defense LP (UDLP) and The University of Texas at Austin Center for Electromechanics (UT-CEM) has completed a significant portion of the testing phase of a trailer mounted compulsator driven 35 mm (round bore equivalent) rapid fire railgun system. The objective of the program is to develop a compact, lightweight pulse power test bed capable of launching 3, 5 round salvos of 185-g integrated launch packages to 1.85 km/s at a firing rate of 5 Hz. Per contractual requirements, the pulse power system is also size compatible with the Amphibious Assault Vehicle (AAV). The pulse power system is developed around a second generation air-core, 4-pole rotating armature, self-excited, compulsator design. The 40 MJ at 12,000 rpm composite rotor stores all 15 shots inertially and is capable of 2.5 GW performance into the 2.21 m long series augmented railgun. This paper describes the CCEMG pulse power supply configuration and highlights important features of the commissioning test plan. The paper then presents test results from mechanical runs, stand alone compulsator (CPA) rectifier tests, short circuit tests, and single shot live fire tests. Finally, CPA performance is compared with predictions for the single shot tests presented.

Use of the amphibious warfare model to evaluate the cost effectiveness of alternative marine corps amphibious assault vehicles

The Marine Corps' current amphibious vehicle will reach the end of its service life around the turn of the century. Therefore, the Marines are planning the design and development of a replacement, designated the Advanced Amphibious Assault (AAA) system. This article describes the methodology and results of a cost and effectiveness analysis performed to support a milestone decision in this program. The analysis first examined the performance of the alternative systems, and then evaluated the overall effectiveness of forces equipped with the alternative systems. The force effectiveness was accomplished using a dynamic, two-sided, air-land-naval warfare model known as the amphibious warfare model. © 1995 John Wiley & Sons, Inc.1 This article is a US Government work and, as such, is in the public domain in the United States of America.