Browse Topic: Occupant protection

Items (684)
ABSTRACT The modeling of a buried charge is a very complex engineering task since many Design Variables need to be considered. The variables in question are directly related to the method chosen to perform the analysis and the process modeled. In order to have a Predictive Tool two main objectives have to be carried out, the first is a verification of the numerical approach with experimental data, the second objective is a sensitivity study of the numerical and process parameters. The emphasis of the present study covers the second objective. To perform this task a comprehensive sensitivity study of fourteen Design Variables was completed which required 1000+ computational hours. The modeling approach that was chosen was the Discrete Particle Method (DPM) to model the Soil and HE and the Finite Element Method for the Structure. The basis for the study was a blast event applied to a model of the TARDEC Generic Vehicle Hull. The Response Parameter was chosen to be the Total Blast Impulse
Jensen, Morten RikardSmith, Wilford
ABSTRACT Over the course of typical survivability analyses for underbody blast events, a multitude of individual cases are examined where charge size, charge location relative to the vehicle, and vehicle clearance from the ground are varied, so as to arrive at a comprehensive assessment. While multi-physics computational tools have reduced the expense and difficulty of testing each loading case experimentally, these tools still often require significant execution and wall-clock times to perform the simulations. In efforts to greatly reduce the time required to conduct a holistic survivability analysis, Fast Running Models (FRMs) have been implemented and validated to act as a surrogate for the computationally expensive finite element tools in use today. Built using a small set of simulations, FRMs generate loading data in a matter of seconds, representing a significant improvement in survivability analysis turnaround time
Li, LiangjunStowe, NicholasVlahopoulos, NickolasMohammad, SyedBarker, CraigThyagarajan, Ravi
ABSTRACT This paper reviews the Army Generic Hull [1-5] as a vital developmental tool for underbody blast modeling and simulation applications. Since 2010, it has been used extensively to help calibrate and validate various numerical software codes and methodologies. These are being used extensively today in the development of underbody armor, as well as mine blast subsystems such as seats, to protect both military vehicles and their occupants. In the absence of easily shareable information in this domain due to data classification, this specially formulated product is a valuable part of any toolset for underbody blast development and product design. Citation: K. Kulkarni, S. Kankanalapalli, V. Babu, J. Ramalingam, R. Thyagarajan, “The Army Generic Hull As A Vital Developmental Tool For Underbody Blast Applications,” In Proceedings of the Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), NDIA, Novi, MI, Aug. 16-18, 2022
Kulkarni, KumarKankanalapalli, SanjayBabu, VenkateshRamalingam, JaiThyagarajan, Ravi
ABSTRACT Occupant safety is a top priority of military vehicle designers. Recent trends have shifted safety emphasis from the threats of ballistics and missiles toward those of underbody explosives. For example, the MRAP vehicle is increasingly replacing the HMMWV, but it is much heavier and consumes twice as much fuel as its predecessor. Recent reports have shown that fuel consumption directly impacts personnel safety; a significant percentage of fuel convoys that supply current field operations experience casualties en route. While heavier vehicles tend to fare better for safety in blast situations, they contribute to casualties elsewhere by requiring more fuel convoys. This study develops an optimization framework that uses physics-based simulations of vehicle blast events and empirical fuel consumption data to calculate and minimize combined total expected injuries from blast events and fuel convoys. Results are presented by means of two parametric studies, and the utility of the
Hoffenson, StevenKokkolaras, MichaelPapalambros, PanosArepally, Sudhakar
ABSTRACT Non-combat tactical vehicle incidents such as rollover are one of the major causes of soldier injuries and deaths. Rollover incidents are usually associated with multiple impacts which result in complex interactions between occupants and hard structural components. Detailed information of occupant responses in such rollover incidents are lacking, and to design effective occupant protection system and safety restraints systems, understanding the vehicle to occupant interaction is essential. The performance of ground vehicles during a rollover event is an important safety and occupant protection requirement for military vehicles. Modeling and simulation are a very useful tool in study and investigation of vehicle rollover characteristics and countermeasure concepts. The main goal of this research is to develop an M&S model of a HMMWV full vehicle system and evaluate the effectiveness of the different restraints systems in a lateral 25 mph rollover tests and its effect on
Babu, VenkateshKang, JianKankanalapalli, SanjaySheng, JimVunnam, MadanKarwaczynski, Sebastian K.Jessup, ChrisDuncan, Mike
ABSTRACT The diverse range of military vehicles and operational conditions share a number of powertrain objectives including high fuel efficiency and fuel adaptability to lessen the logistical impact of conflict; low heat rejection to minimize the cooling system losses, vulnerability and powertrain package space; tractive power delivery to provide superior mobility for the vehicle; and light weight to allow for more armor to be used and/or payload to be carried. This paper first provides an overview of the operational powertrain requirements of military vehicles. A review the processes used to integrate powertrain components into an optimized system specifically developed for modern combat vehicle applications is then provided, including an example of how the process was employed to develop an advanced powertrain for a tactical vehicle demonstrator based on military optimized off-the-shelf components. The paper concludes with a summary of some further military specific engine and
Hunter, Gary
ABSTRACT The presented work discusses how to make a V/L analysis of a vehicle based on an RHA equivalence. It is shown how the approach works using small examples and an impact of an M1 helmet. Further, different V/L analyses of the GAZ-2975 vehicle are displayed. Considered Response parameters are the VAA damage maps, Expected Protection Capability plot, and damage area fractions. Explicit Finite Element models are used to find the critical RHA equivalent armor thickness at normal impact. It is done with terminal ballistic models for three materials; RHA, Aluminum 5083-H116, and Armox 500T. The values found are used in a V/L analysis. A sensitivity study of eight relevant V/L design parameters is carried out on the driver side section of the GAZ-2975 vehicle with an EPC value as the response parameter. Citation: Morten Rikard Jensen, Steven Grate, “Procedure for Fast Ballistic Vulnerability Simulation of Armored Vehicles Supported by Finite Element Results and an Extensive Numerical
Jensen, Morten RikardGrate, Steven
ABSTRACT Consumer demand and regulatory pressure have forced automakers to develop features designed to increase passenger car safety regardless of road surface or weather condition. In response, the intelligent tire, proposed in the APOLLO report, is introduced and the parameters useful for traction control system development are identified. Traction control system models are introduced and discussed. A simple vehicle model based on the quarter-car is presented, incorporating a traction control system and tire friction model. This model utilizes the LuGre friction model to relate tractive force to slip ratio and road surface friction level. A sliding-mode control strategy is chosen to model traction control behavior. Three case studies are conducted on two simulated road surfaces to show the interaction between estimated friction level in the sliding-mode control strategy and the tire friction model. To simulate the intelligent tire, where the road surface friction level is directly
Binns, RobertTaheri, SaiedFerris, John B.
ABSTRACT It is of considerable interest to developers of military vehicles, in early phases of the concept design process as well as in Analysis of Alternatives (AoA), to quickly predict occupant injury risk due to under body blast loading. The most common occupant injuries in these extremely short duration events arise out of the very high vertical acceleration of vehicle due to its close proximity to hot high pressure gases from the blast. The primary objectives of this paper are to conduct an extensive parametric study in a systematic manner so as (1) to determine if a single blast loading parameter is sufficient to adequately characterize the occupant injury, at least for the duration of typical blast events (0-20ms) and (2) to create look-up tables and/or an automated software tool that decision-makers can use to quickly estimate the different injury responses for both stroking and non-stroking seat systems in terms of such a parameter
Kulkarni, Kumar BRamalingam, JaisankarThyagarajan, Ravi
ABSTRACT Military vehicles in the field are often required to perform severe emergency maneuvers to avoid obstacles and/or escape enemy fire. This paper proposes a combined direct yaw control (DYC) and emergency roll control (ERC) system to mitigate rollover in the studied military vehicle. The DYC uses a differential braking strategy to stabilize the vehicle yaw moment and is intended to reduce the risk of untripped rollovers and also help prevent the vehicle from skidding out, thus allowing the driver to maintain control of the vehicle. The ERC uses actuators located near the vehicle suspension to apply an upward force to the vehicle body to counter the roll angle. An off-road tire model was used with the overall vehicle model in commercially available vehicle simulation software to simulate emergency maneuvers on various driving surfaces. Simulation results show that the proposed control strategy helps prevent both tripped and untripped rollovers on various driving surfaces
Hopkins, BradTaheri, SaiedAhmadian, MehdiReid, Alexander
ABSTRACT The inclusion of energy-absorbing (EA) seats in combat vehicles has been shown to greatly reduce the likelihood of upper-body injuries during mine blast events. A drop tower is one of the common low-cost methods of testing an energy-absorbing seat to determine the vehicle acceleration and associated level of blast that it can protect against. However, the lack of a standard drop tower test procedure for mine blast purposes means that different facilities perform tests and analyze and report results in an inconsistent manner. As a consequence, the reported performance of any given seat tested in a drop tower may not accurately reflect the degree to which it would protect a soldier during an actual blast event. This paper describes the nature of the problems associated with current drop tower testing, and proposes a solution to eliminate much of the ambiguity surrounding test results. We will describe proposed test and analysis methods that can lead to a more accurate and
Eridon, JamesCory, Josh
ABSTRACT Southwest Research Institute® (SwRI®), under contract to US Army CCDC-GVSC, went through an extensive design, analysis, manufacturing, and testing project for the development of energy absorbing dampers and lightweight floor systems to provide protection to the warfighter inside vehicles that are exposed to underbelly blasts or similar threats. The dampers have been designed to remain locked during a wide variety of road vibration and shock loads, but to release and absorb energy through elongation, providing protection to occupants when the blast threats are encountered. This range of input criteria was challenging to satisfy in a passive system that is lightweight, relatively inexpensive, easy to install, and effective over a wide range of blast loads and occupant weights (5% through 95%). The SwRI work concentrated on designing two subsystem sizes – the individual dampers themselves in component tests, and ½ scale coupon level tests that include the dampers, floor systems
Mathis, J.Grimm, M.Mullin, S.Burguess, V.
ABSTRACT With US military casualties mounting due to Improvised Explosive Devices (IEDs) and other roadside bombs, improving the protective capabilities of armored vehicles for service personnel is of paramount importance. Accurate numerical simulations of the blast event provide a means to quickly and economically evaluate the blast-protection performance of armored vehicles, and to develop improved blast countermeasures. This effort developed computational simulations of a system intended to mitigate blast accelerations to a level where the acceleration is no longer a lethal threat to the occupants of an armored vehicle. The hypothesis is that through the manipulation of the mass ratio, stiffness and damping properties of a dual-hull system, the capability of current Mine Resistant Ambush Protected (MRAP) vehicles can be greatly improved. The results show that, in comparison to the standard single-hull vehicle, the dual-hull vehicle reduces head injury criteria by 95.7%, neck
Schaffner, GrantMiller, Adam
ABSTRACT To reduce the hazard for service personnel involved in current field operations, it is necessary to improve the safety and structural integrity of transport vehicles subjected to buried explosive material. Numerical simulation of the detonation effects of an Improvised Explosive Device (IED) on a vehicle and its occupants can provide tremendous value in this effort. Such events involve a range of complex phenomena at various dimensional and temporal scales, and it is not practical to capture all physical phenomena with just one single numerical method. A practical solution to this problem is proposed using a combination of Smoothed Particle Hydrodynamics (SPH) and Finite Elements. Various numerical techniques have been proposed for simulating buried explosive over the past 30 years and this work has been previously described by many authors. However, the ability to define blast input parameters together with a soldier-centric simulation approach that includes human body and
Dooge, DanielDwarampudi, RameshSchaffner, GrantMiller, AdamThyagarajan, RaviVunnam, MadanmohanBabu, Venkatesh
ABSTRACT Through Army SBIR funding, NanoSonic has designed a next-generation multipurpose Spall Protective, Energy Absorbing (SPEA™) HybridSil® material that has the potential to provide vehicle occupants with pioneering combinatorial protection from 1) fragmentation behind-armor debris (BAD), 2) high velocity head / neck impact, and 3) fire during underbody blast, crash, and rollover events. This innovative multilayered ensemble consists of highly flame resistant, energy absorbing polyorganosiloxane foams, molded ultrahigh molecular weight polyethylene panels, and carbon fiber reinforced polymer derived ceramic composites. The technical foundation for this effort was provided through independent 1) MIL-STD-662 FSP ballistic testing with The Ballistics and Explosive Group at Southwest Research Institute (SwRI); 2) FMVSS 201U head impact testing with MGA Research Incorporation; and 3) ASTM E1354 fire resistance testing with the Fire Technology group at SwRI. Fragment simulating
Baranauskas, VinceKlima, Julie
ABSTRACT The study describes the development of a plug-in module of the realistic 3D Digital Human Modeling (DHM) tool RAMSIS that is used to optimize product development of military vehicle systems. The use of DHM in product development has been established for years. DHM for the development of military vehicles requires not only the representation of the vehicle occupants, but also the representation of equipment and simulation of the impact of such equipment on the Warfighter. To simulate occupants in military vehicles, whether land or air based, realistically, equipment must become an integral part of the extended human model. Simply attaching CAD-geometry to one manikin’s element is not sufficient. Equipment size needs to be scalable with respect to anthropometry, impact on joint mobility needs to be considered with respect to anatomy. Those aspects must be integrated in posture prediction algorithms to generate objective, reliable and reproducible results to help design engineers
Kuebler, ThorstenWirsching, HansBarnes, David
ABSTRACT The primary focus of this effort is to evaluate the roof liner technology’s ability to reduce the head injury criteria (HIC) and head acceleration to mitigate vertical impact related injures to mounted crew injures which may occur during top and bottom threat events. In an effort to reduce the likelihood of head injury during top and bottom threat attacks, an adequate roof liner is needed to reduce the force exerted on the solider. The roof liners were able to pass all system level tests. The successful system level testing confirmed the blast mat technology’s TRL-6 recommendation. Citation: J. Klima, “Developing Performance and Operating Requirements for Energy Attenuating (EA) Roof Liner for all U.S. Army Military Vehicles”, In Proceedings of the Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), NDIA, Novi, MI, Aug. 10-12, 2021
Klima, Julie
ABSTRACT The CAMEL program focused on force protection and demonstrated the possibility to protect occupants through higher underbelly blast levels than normally or previously observed. This required a holistic vehicle systems engineering approach to mitigate blast injuries that both optimized existing systems as well as developed new technologies. The result was zero injury to all occupants as assessed by 5th, 50th, and 95th percentile encumbered ATDs during survivability blast testing. Twelve full scale objective-level blast tests were performed on over seventy fully-instrumented ATDs without a single lower-extremity injury. The lower limb protection was provided by an isolated floor system. This system was developed from the ground-up and occupant-out during the CAMEL program. This paper chronicles the CAMEL floor system’s creation, design, testing, and development process
Kwiatkowski, KevinWatson, ChristopherKorson, Chantelle
ABSTRACT The objective of this study was to optimize the occupant restraint systems (including both seatbelt and airbag) in a light tactical vehicle under frontal crash conditions through a combination of sled testing and computational modeling. Two iterations of computational modeling and sled testing were performed to find the optimal restraint design solutions for protecting occupants represented by three size of ATDs (namely Hybrid-III 5th percentile female ATD, 50th percentile male ATD, and 95th male ATD) and two military gear configurations, namely improved outer tactical vest (IOTV) and SAW Gunner configuration using a tactical assault panel (TAP). The sled tests with the optimized seatbelt and airbag designs provided significant improvement on the head, neck, chest, and femur injury risks compared to the baseline tests. This study demonstrated the benefit of adding a properly designed airbag and advanced seatbelt to improve the occupant protection in frontal crashes for a light
Hu, JingwenOrton, NicholeChen, CongRupp, Jonathan D.Reed, Matthew P.Gruber, RebekahScherer, Risa
ABSTRACT Ground combat vehicles can operate in regions characterized by various types and severities of injuries – resulting from improvised explosive devices (IEDs), gunfire or heat illness – as well as extreme climates such as desert environments. Because of the wounded warrior’s compromised physical condition, their thermal surroundings within the vehicle are especially important. This paper presents insights gleaned from the Army medical community, as well as a simple study of the effect of heat on soldiers in a ground combat vehicle using CFD / thermal modeling and simulation tools and methodologies. In particular, an Army-patented method for controlling body temperature via skin temperature feedback together with a cooling vest and pants ensemble is employed
Tison, NathanSmith, Rob E.
ABSTRACT The Blast Event Simulations sysTem (BEST) is a synthesis tool that provides a seamless and easy-to-use coupling between existing and commercially available LS-DYNA solvers and Anthropomorphic Test Device (ATD) models for a complete sequence of explosive simulations. BEST driven simulations capture the soil/explosive/vehicle/occupant interaction. In this paper a blast simulation analysis conducted by BEST for a generic but representative vehicle is presented. The vehicle is subjected to the blast load created by an explosive buried underneath the vehicle. An ATD model is placed inside the vehicle in order to capture the loads created on the lower legs of an occupant due to the explosion. Technical details with respect to the various models engaged in the simulation are presented first. The results and the physical insight which can be gained by the analysis are discussed. A series of design modifications which add minimal weight are introduced in the vehicle structure, such as
Vlahopoulos, NickolasZhang, Geng
ABSTRACT Computational models are widely used in the prediction of occupant injury responses and vehicle structural performance of ground vehicles subjected to underbody blasts. Although these physics based computational models incorporate all the material and environment data, the classic models are typically deterministic and do not capture the potential variations in the design, testing and operating parameters. This paper investigates the effect of one such variation in physical tests, namely, variations in the position of occupant setup on the occupant injury responses. To study the effects of occupant position, a series of vertical drop tower tests were performed in a controlled setup. A vertical drop tower test involves an Anthropomorphic Test Device (ATD) dummy positioned on a seat and the setup is dropped on an energy attenuating surface, thus producing a desired shock pulse on the seat structure. The experimental data was analyzed for sensitivity of occupant position and ATD
Ramalingam, JaisankarPrall, Nancy
ABSTRACT In this study, the water content and dry density data from field measurement of the ATC Engineered Roadway Soil (E-RW) were analyzed first, and their means and standard deviations were derived. Based on corresponding ERDC lab test data, each soil parameter in both material model and EOS equation was then expressed as a function of soil water content and dry density by 3D or 4D surface fitting. Thus mapping equations from soil water content and dry density to soil parameters were established. With an assumption of normal distribution for both soil water content and dry density, a stochastic soil model was developed for the ATC Engineered Roadway Soil. Modeling and simulation examples were provided to demonstrate how to apply the developed stochastic soil model to carry out underbody blast Monte Carlo simulation for generating vehicle and occupant responses clouds, and how to estimate the low and up bounds of occupant and structure response with certain confidence level
Kang, JianSheng, JianpingAkers, StephenWilliams, Neil
ABSTRACT The work presented here comprises preliminary results for calibrating the IMPETUS Afea Hybrid III 50th percentile Male ATD for a blast scenario. The calibration of the ATD model based upon the requirements defined for frontal crash impact are presented followed by a discussion of the blast survivability tests that were performed at General Dynamics Edgefield Test Center in South Carolina. The model setup for the calibration based upon the blast tests are presented which includes a discussion of the seating and blast models. Preliminary numerical results for Lumbar and Lower Tibia forces are compared with the experimental results. The correlation was good and calibration of the remaining critical parameters continues
Jensen, Morten RikardHonaker, MikeBoglaev, Alex
ABSTRACT This paper presents a vehicle design parameter screening, the first portion of our MDO efforts on occupant-centric vehicle design. The study uses a full simplified vehicle by considering occupant centric survivability performance under underbody mine blast loading. The top 10 design variables have been identified by TARDEC SMEs and analyzed systematically. 32 finite element models were built to represent fractional factorial combinations of these design parameters and used to determine the main contributors to vehicle structure response and occupant injury potentials. Four preferred design parameter selections have been found in this effort to achieve improved occupant survivability performance and structural response under underbody blast loadings. They are: optimized seat energy absorption system, higher standoff distance and vehicle mass, double-V underbody shape without structural reinforcement, and smaller vehicle width. The study found and confirmed that an optimized
Sheng, JianpingMechergui, DaveVunnam, MadanArepally, SudhakarBednarz, DaveHsieh, Ching
ABSTRACT There have been several hundred rollovers in military vehicles in the last decade of deployment, of which approximately fifty percent are fall-based that occur during off-road operations. Off-road fall-based rollovers occur at lower speeds during road breakaway when the soft road gives way underneath the vehicle on one side as the soil is unable to support the vehicle load (Figure 1). A simulation-based study was conducted to explore potential off-road rollover mitigation benefits for the heavy vehicles with higher center of gravity such as MRAPs, MATV, and JLTV through the use of high performance active suspension systems. The study developed a system architecture based on the ElectroMechanical Suspension (EMS) technology and developed a medium fidelity MATLAB-Simulink-DADS model. Simulation results indicated substantial rollover mitigation benefits for MRAP/JLTV class vehicles, especially in road breakaway scenarios. Potential DoD beneficiaries include the Army and Marines
Beno, JosephBryant, AdamSingh, AmandeepKovnat, AlexanderHayes, RichardWeeks, Damon
ABSTRACT Structural optimization efforts for blast mitigation seek to counteract the damaging effects of an impulsive threat on critical components of vehicles and to protect the lives of the crew and occupants. The objective of this investigation is to develop a novel optimization tool that simultaneously accounts for both energy dissipating properties of a shaped hull and the assembly constraints of such a component to the vehicle system. The resulting hull design is shown to reduce the blast loading imparted on the vehicle structure. Component attachment locations are shown to influence the major deformation modes of the target and the final hull design
Tan, HuadeGoetz, JohnTovar, AndrésRenaud, John E.
ABSTRACT Survivability of a welded vehicle hull is directly tied to the performance of the grade of steel armor used. Selecting the highest performing grade of armor that can be welded into a specific location on a vehicle will improve survivability. While rolled homogeneous armor is the simplest to weld, challenges in welding high hard, and especially ultra high hard, are well known. Preventative measures to avoid weld cracking in vehicle structures can lead to increased costs during fabrication. Cracking of welds, both seen and unseen, in deployed vehicles directly impacts the survivability of the vehicle. Weld cracking during deployment further magnifies repair costs and leads to non-mission capable status. This analysis examines the weldability, ballistic/blast performance, and underlying metallurgy of Flash® Processed steels that have been tested by Army, Academia, and Industry. Citation: G. Cola, “Flash® 600 Ultra High Hard: Room-Temp ER120S-1 Weldability Tekken, H-Plate
Cola, Gary M
ABSTRACT The performance of ground vehicles during a rollover event is an important safety and occupant protection requirement for military vehicles. Modeling and simulation is a very useful tool in study and investigation of vehicle rollover characteristics and countermeasure concepts. This study presents two methods of simulating the rollover events. The first one uses Full System Method (FSM), where all the components are modelled as is and are evaluated. The second method is a reduced order modelling method (ROMM) using integration of the resulted kinematics data from FSM into the vehicle model with occupant & restraints. The FSM & ROMM methods were applied to simulate two HMMMV rollover events, and the results from both methods show that simulation and test data agreed fairly well. Computational time reduced by the ROMM was about 53% of that of the FSM. ROMM approach not only saves significant computational time but also increases robustness of the simulation. Citation: V. Babu, J
Babu, V.Kang, J.Kankanalapalli, S.Sheng, J.Vunnam, M.Karwaczynski, S. K.Jessup, C.Duncan, M.Paulson, K.
ABSTRACT Seatbelt-mounted airbag is a new type of occupant restraint system, in which the airbag is integrated into the seatbelt and hence can be easily and quickly implemented into the current tactical vehicles without significant vehicle structure or interior changes. The objective of this study was to develop, optimize, and demonstrate seatbelt-mounted airbag designs for reducing occupant injury risks in a light tactical vehicle under frontal crashes. A total of 19 sled tests and over 30 FE simulations were performed to find the optimal seatbelt-mounted airbag designs for protecting occupants represented by three sizes of ATDs and two military gear configurations. Various lap-belt-mounted airbag and shoulder-belt-mounted airbag designs were evaluated for driver, front-seat passenger, and rear-seat passenger locations in a tactical vehicle. The test and simulation results showed that the optimized designs substantially reduced the occupant injury risks to the head, neck, and chest
Hu, JingwenOrton, NicholeBoyle, KyleAshok, NikhilKlima, JulieStaniak, CeliaScherer, RisaReed, Matthew
ABSTRACT The successful fielding of occupant protection technologies require understanding their behavior and performance under field-like conditions. To achieve this, the Occupant Protection Laboratory (OPL) at Selfridge Air National Guard Base (SANGB) uses a drop tower, called the Sub-System Drop Tower (SSDT), and a vertical accelerator, called the Crew Compartment Under-Body Blast Simulator (CCUBS). These two systems have the capability to deliver specified acceleration profiles to items, such as blast-mitigating seats under test. To gain confidence that the two systems are producing similar testing conditions for a given system, a series of experiments was designed to determine the existence of a correlation between the two systems. A representative seat and an Anthropomorphic Test Device (ATD) were tested under similar acceleration profiles on both systems. Tests were initially conducted without a payload to determine the testing parameters for each system and to determine the
Foster, Craig DRudek, Matthias
ABSTRACT TARDEC researched head impact protective, energy attenuating materials for use in U.S. Army Ground System Vehicle (GSV) applications. The purpose of the project is to reduce potential head impact related mounted crew injuries and deaths which may occur during underbody blast, crash and rollover events. Commercial-off-the-shelf materials were evaluated for their energy attenuating performance. Exposed surface materials in combination with core material were also researched and evaluated. Baseline vehicle testing was conducted to understand the current head impact criterion. The results of this effort identified solutions which may potentially meet the needs of the Army to reduce head impact related injuries which may occur during crash, rollover and blast events. TARDEC used the knowledge gained from this project to create performance specification requirements for interior head impact protective components and materials for use in U.S. Army vehicles
Klima, JulieMarquardt, Rebecca
ABSTRACT In order to reduce the frequency and severity of warfighter head, neck, and spine injuries associated with military vehicle underbody IED and AVL blasts, crash, and rollover, Hy-Tek Manufacturing Co. Inc. (HMC) has designed, fabricated, tested, and optimized its Vehicle Roof Inflatable Impact Bladder (VRIIB). Comprised of two (2) thin and impermeable airbags separated by semi-rigid force distribution plates; the VRIIB is designed to be mounted on the interior roof panel of military combat vehicles in a deflated state. During IED or AVL detonation, the VRIIB inflates by means of a COTS airbag inflator to provide a significant reduction in the rate at which a warfighter’s head or neck decelerates against the rigid vehicle roof panel. The VRIIB is designed to remain inflated and functional for a protracted period of time after its initial actuation in order to protect vehicle mounted warfighters from follow-on blast related roof impacts, subsequent vehicle rollover and/or vehicle
Middlebrook, DonaldJude, JohnPeck, Jason
ABSTRACT This paper addresses the balance of performance parameters of occupant survivability and vehicle mobility during trade study analysis and simulation for the TARDEC Demonstrator for Novel Design (DFND) vehicle concepts. Occupant survivability and vehicle mobility are often competing attributes in the design of current armor protected tactical and combat ground vehicles. Increased armor weight and high stand-off height parameters are favorable for occupant survivability during underbelly blast events but are detrimental to vehicle dynamics mobility performance. TARDEC and Pratt & Miller Engineering are implementing a motorsports based design process and simulation approach using a holistic systems engineering trade study to develop potential concepts that maximize force protection, vehicle mobility, and vehicle survivability. A number of specialized simulation tools including hypervelocity explicit finite element analysis and multi-body simulation are used interactively to
Kaplin, Casey A.Houghton, Kristian B.
ABSTRACT Fiber reinforced thermoset composites are well known for delivering 50% or more weight savings when compared with steel components while also providing strength, stiffness, and toughness. Nanoparticle additives have been shown to significantly increase the mechanical properties of thermoplastic and thermoset polymer matrices over the base matrix values. Extensive testing and characterization of composites containing graphene nanoplatelets (GnP) has been conducted and reported by XG Sciences’ (XGS) collaborators at the Michigan State University (MSU) Composite Materials and Structures Center. In a recent program with U.S. Army Tank Automotive Research, Development and Engineering Center (TARDEC), MSU investigated lightweight composites for blast and impact protection. High strain rate test facilities as well as high speed photography and non-destructive interferometry-based evaluation techniques were used to evaluate blast performance. The experimental results are presented
Privette, R.Fukushima, H.Drzal, L.T.Robinson, M.
ABSTRACT A comprehensive analysis of data collected during an evaluation of blast energy–attenuation (EA) seats was conducted to review the performance of commercially available and prototype seat assets. This evaluation included twelve models of seats tested at two separate drop severities with three sizes of anthropomorphic test devices (ATDs) to develop test methodologies and assess the appropriateness of using injury assessment reference values (IARVs) for all occupant sizes
Bosch, KellyHarris, KatrinaClark, DavidScherer, RisaMelotik, Joseph
Full-vehicle, End-to-End Underbody Blast (UB) simulations with LS-DYNA ALE (Arbitrary Lagrange-Eulerian) method have been common practice at the Tank Automotive Research, Development and Engineering Center (TARDEC) for the last several years to support Program Managers in the Army Acquisition and Science & Technology (S&T) Community of military ground vehicles. Although the method has been applied extensively and successfully, the demand for reducing the simulation time has been very high. Very recently a new method, Structured ALE (S-ALE), was developed in LS-DYNA by taking advantage of structured mesh to speed up the calculation time. In this paper several case studies for underbody mine blast simulations were analyzed by both ALE and S-ALE methods. The comparative results show the new method is very promising in improving the simulation time as well as the Massively Parallel Processing (MPP) scalability
Hsieh, ChingVunnam, MadanBhalsod, DilipChen, Hao
ABSTRACT Modeling and Simulation (M&S) of underbody blast to vehicles can take a significant amount of time, often days to months, to run. This significant run time is due to the need for coupled Eulerian-Lagrangian computational algorithms to be used in order to accurately represent the effect of an underbody blast to a vehicle and its occupants. Several techniques exist which can significantly reduce the time it takes to complete such a simulation without affecting its accuracy, two of which will be emphasized here. These techniques are 2-D to 3-D mapping of the Eulerian domains and Early-Deletion of the Eulerian elements. For detailed vehicle simulations, simulation rates have been demonstrated to be 4-6 times faster along with a theoretical increase in accuracy and a decrease in troubleshooting time
O’Bruba, Joseph
Abstract Present day Army ground vehicles are equipped with numerous communications (COMMS) and counter improvised explosive device (C-IED) antenna systems. These platforms often have numerous highly visible antennas to support the large bandwidth and high power requirements of military radios and jammers. Currently, the demand for additional spectrum functionality for a ground vehicle ultimately leads to another antenna crowding the surface of the vehicle and reducing the survivability by increasing its visual signature. The visual signatures of large legacy whip antennas not only reduce battlefield survivability but also hinder the mobility of the vehicle in tight urban theater scenarios. With so many antenna systems onboard, mutual and joint force interoperability is of grave concern as the cosite interference between antenna systems significantly reduces its communications range and could hamper jamming effectiveness. The goal of the Army initiated Embedded Platform Antenna System
Johnson, ShikikMizan, WaliulKabir, Nahid
ABSTRACT Motorized ground forces spend considerable resources in equipping for situational awareness capabilities. Given requirements spanning command, control, surveillance, and reconnaissance of a battlefield, there has been no single mast technology that can support each of these with elevated sensors and weapons. A tough, extremely low weight modular mast system has been designed to be quickly attached or removed from a ground vehicle to provide different operational capabilities depending on the payload. The design allows for easy modification to fit functional needs on different vehicles and platforms. At the heart of the technology is a proprietary super-fiber pressurized tube which elevates the payload on a column of moderate gas pressure eliminating cumbersome hydraulic/mechanical systems. An internal, simple alignment system and gyroscope-maintained verticality allow a stable, elevated platform without introducing instability to the vehicle. The system is capable of
Townsend, Phillip L.Bhatnagar, VivekMartinez, RudyWarnakulasuriya, Frank
ABSTRACT The Optical Warhead Lethality Sensor Suite (OWLSS) was designed specifically for tracking dense, fast fragment fields generated in warhead arena testing. OWLSS is an optimized hardware/software solution for measuring correlated properties of detonating warhead fragment distributions. The OWLSS automated track algorithm returns time-dependent 3D position, velocity, size, aerodynamic drag, and mass estimates for each fragment tracked. These data products fill a significant gap in our ability to characterize munitions for weapon effectiveness modeling. Furthermore, the system is modular and can be reconfigured for many tracking applications. In this paper, we present an overview of legacy arena measurement techniques, an overview of the OWLSS optical tracking approach, and we discuss how OWLSS can be employed to collect test data needed to improve the survivability of armored vehicles. Citation: J. P. Burke, Jr, J. Roe, S. F. Henke, B. P. Walker, W. Koons, “An Enhanced Optical
Burke, James P.Roe, JeffreyHenke, Steven F.Walker, Bradley P.Koons, William A.
ABSTRACT As part of DARPA’s Adaptive Vehicle Make (AVM) portfolio of programs, blast and ballistic survivability analysis tools were developed. The intent of these tools was to facilitate design and design optimization by making it possible for designers to perform survivability analysis from CAD and to automate the survivability analysis pipeline to allow optimization codes to invoke the survivability tools and obtain results. This paper describes some of the tools and their capabilities through highlighting five innovations utilized in the program: multi-fidelity modeling; automated meshing and welding; uncertainty quantification and 95% bounds; a large material property database and more accurate blast loads; and automating the entire computational pipeline
Walker, James D.Chocron, SidneyMoore, Michael S.Willden, Gregory C.
ABSTRACT Improvised Explosive Devices (IEDs) and mines pose significant threat to military ground vehicles and soldiers in the field. Due to the severity of the forces exerted by a blast, ground vehicles may undergo multiple sub-events subsequent to an explosion, including local structural deformation of the floor, gravity flight and slam-down. The current method of choice to simulate the effect of a shallow-buried IED or mine on a Lagrangian vehicle model, is a fluid-structure interaction with the environment modelled with an Eulerian formulation (explosive, ground, air) [1]. This method, also called Arbitrary Lagrangian-Eulerian (ALE), is more expensive and involved than pure structural methods (usually pressure loads applied to the vehicle surface). However, it allows for taking into account the effect of the shape, type and size of the charge and the soil characteristics on the impulse transmitted to the vehicle. Three approaches are proposed to reduce the analytical simulation
Parthasarathy, MohanKosarek, Philip G.Santini, JulienThyagarajan, Ravi
Seventeen research posters were prepared and presented by student authors. The posters covered a wide breadth of works-in-progress and recently completed projects. Topics included a variety of body regions and injury scenarios: Biofidelity Corridors of Powered Two-Wheeler Rider Kinematics from Full-Scale Crash Testing Using Postmortem Human Subjects, Meringolo et al. Cervical Vertebral and Spinal Cord Injuries Remain Overrepresented in Rollover Occupants, Al-Salehi et al. The Effect of Surfaces on Knee Biomechanics during a 90-Degree Cut, Rhodes et al. Investigating the Variabilities in the Spinal Cord Injury in Pig Models Using Benchtop Test Model and Ultrasound Analyses, Borjali et al. Relationship between Tackle Form and Head Kinematics in Youth Football, Holcomb et al. Comparing Motor Vehicle Collision Injury Incidence between Pregnant and Nonpregnant Individuals: A Case–Control Study, Levine et al. Development of an Automated Pipeline to Characterize Full Rib Cage Shape
Bautsch, Brian T.Cripton, Peter A.Cronin, Duane
Extreme out-of-position pre-crash postures may need high-force pre-pretensioner (PPT) for effective repositioning (Mishra et al., 2023). To avoid applying a high force on the chest, we hypothesized that in case of these extreme postures the PPT may be activated in the absence of a pre-crash motion as a cautionary measure. Therefore, the aims of this study were: (1) to understand the effect of the PPT in repositioning a forward-leaning occupant in static conditions and (2) to characterize occupants’ kinematic variability during repositioning. Sixteen healthy volunteers (8 males, 8 females, 23.8 ± 4.2 years old) were seated with a 40° forward posture on a vehicle seat and restrained with a 3-point seat belt equipped with a PPT. Two PPT seatbelt conditions were examined: low PPT (100 N) and high PPT (300 N). Head and trunk rearward displacements relative to the initial forward-leaning position at 350 ms from PPT onset were collected with a 3D motion-capture system and compared between
Witmer, MaitlandGriffith, MadelineGraci, Valentina
The primary purpose of the active safety feature is to reduce the danger of a collision between the car and an obstruction. To improve occupant safety, active safety systems must be included on all new vehicles; nonetheless, not all incidents are preventable. The frequency of incidents on the road has recently increased in tandem with the number of cars, making it critical to investigate the crashworthiness of a vehicle because human life is at the top of the priority list. This study examines an occupant's responses prior to a crash event, as well as studies into how occupant posture influences injury data. Most of the existing research focuses on the pre-crash event or the occupant's optimal seated position. However, it is critical to understand an occupant's reflex or behavior during the pre-crash event, when the occupant is typically not in an appropriate seating posture due to the panic reflex. As a result, an occupant's reflex in a panic situation will change their seating
Shankara Murthy, SantoshSrinivasa, PraveenCK, UmeshPatil, ShubhamJois, Rahul
Energy efficiency in both internal combustion engine (ICE) and electric vehicles (EV) is a strategic advantage of automotive companies. It provides a better user experience that emanates amongst others from the reduction in operation expenses, particularly critical for fleets, and the increase in range. This is especially important in EVs where customers may experience range anxiety. The energetical impact of using the air conditioning system in vehicles is not negligible with power consumptions in the range of kilowatts, even with a stopped vehicle. This becomes particularly important in areas with high temperature and humidity levels where the usage of the air conditioning systems becomes safety factor. In such areas, drivers are effectively forced to use the air conditioning system continuously. Hence, the air conditioning system becomes an ideal choice to deploy control strategies for optimized energy usage. In this paper, we propose and implement a control strategy that allows a
Jaybhay, SambhajiKapoor, SangeetKulkarni, Shridhar DilipraoPalacio Torralba, JavierLocks, Olaf
Effective thermal management is crucial for vehicles, impacting both passenger comfort and safety, as well as overall energy efficiency. Electric vehicles (EVs) are particularly sensitive to thermal considerations, as customers often experience range anxiety. Improving efficiency not only benefits customers by extending vehicle range and reducing operational costs but also provides manufacturers with a competitive edge and potential revenue growth. Additionally, efficient thermal management contributes to minimizing the environmental impact of the vehicle throughout its lifespan. Digital twins have gained prominence across various industries due to their ability to accelerate development while minimizing testing costs. Some applications have transitioned to comprehensive three-dimensional models, while others employ model reduction techniques or hybrid approaches that combine different modeling methods. The discovery of unknown working mechanisms, more efficient and effective control
Palacio Torralba, JavierKapoor, SangeetJaybhay, SambhajiLocks, OlafKulkarni, Shridhar DilipraoShah, Geet
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