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The 16 papers in this technical paper colection present advancement of auto safety-related technologies that deal with roof crush testing, pedestrian safety, front, side and rear impact, simulation of interior head impact, FE study of factors on risk of KTH injuries in frontal impact, CAE methods and testing, and field modeling and assessment techniques.

This technical paper collection contains 20 papers presenting new technologies and research in the area of vehicle rear-end collision, rollover collision and lateral impacts. Papers may be related to analysis of crash compatibility, statistical data analysis, design of vehicle systems, biomechanics and dummy development. To see a listing of papers included in this special publication, click on the papers link below.

Hybrid Electric Drive (HED) provides the potential to improve military vehicle capabilities beyond the well understood fuel economy benefits. Additional HED benefits for military operations can be realized in the areas of mobility, survivability, lethality, power generation and maintainability. General Dynamics Land Systems (GDLS) continues to demonstrate significant advantages that HED can offer to military vehicle platforms. This presentation will focus on the advanced military capabilities provided by HED utilizing in-hub wheel motors and include a summary of GDLS demonstrator vehicles with integrated HED. Presenter Andrew Silveri, GENERAL DYNAMICS LAND SYST

The 23 papers in this technical paper collection address occupant protection with regards to rear impact, rollover, and side impact. Topics include: the effectiveness of curtain side air bags; side impact sensing calibration; door side impact countermeasure; off-road rollover dynamics; steer-induced rollovers; estimating variation in roof strength; occupant pocketing kinematics during whiplash assessments; rear occupant head restraint interaction in high-severity rear impact using BioRID and HIII; and more.

The 13 papers in this technical paper collection look at occupant protection in terms of structural crashworthiness and safety test methodology. Topics covered include: crash energy in vehicle-to-vehicle (VTV) impacts; plastic beams for automobile low-speed rear impact; evaluation of dynamic roof deformation in rollover crash tests; vehicle integrated non-intrusive monitoring of driver biological signals; and more.

The 22 papers in this technical paper collection discuss occupant safety, including rollover and side impact, safety test methodology, and structural crashworthiness. Topics covered included vehicle design, restraint systems design, crash test analysis, CAE simulations and statistical trends analysis, post-crash pedestrian kinematics, and more. The 23 papers in this technical paper collection discuss occupant safety, including rollover and side impact, safety test methodology, and structural crashworthiness. Topics covered included vehicle design, restraint systems design, crash test analysis, CAE simulations and statistical trends analysis, post-crash pedestrian kinematics, and more.

This technical paper collection covers papers with an emphasis on, but not limited to, innovative ideas to enhance automotive safety with improved material constitutive modeling, analysis method developments, simulation and pre/post processing tools, optimization techniques, crash code developments, finite element model updating, model validation and verification techniques, dummies and occupants, restraint systems, passive safety as well as lightweight material applications and designs.

Papers with an emphasis on, but not limited to, innovative ideas to enhance automotive safety with improved material constitutive modeling, analysis method developments, simulation and pre/post processing tools, optimization techniques, crash code developments, finite element model updating, model validation and verification techniques, dummies and occupants, restraint systems, passive safety as well as lightweight material applications and designs are included in the collection.

Papers with an emphasis on, but not limited to, innovative ideas to enhance automotive safety with improved material constitutive modeling, analysis method developments, simulation and pre/post processing tools, optimization techniques, crash code developments, finite element model updating, model validation and verification techniques, dummies and occupants, restraint systems, passive safety as well as lightweight material applications and designs are included in the collection.

Abstract This article investigates the fuel savings potential of a series hybrid military truck using a simultaneous battery pack design and powertrain supervisory control optimization algorithm. The design optimization refers to the sizing of the lithium-ion battery pack in the hybrid configuration. The powertrain supervisory control optimization determines the most efficient way to split the power demand between the battery pack and the engine. Despite the available design and control optimization techniques, a generalized mathematical formulation and solution approach for combined design and control optimization is still missing in the literature. This article intends to fill that void by proposing a unified framework to simultaneously optimize both the battery pack size and power split control sequence. This is achieved through a combination of genetic algorithm (GA) and Pontryagin’s minimum principle (PMP) where the design parameters are integrated into the Hamiltonian function.

The continual reduction of diesel engine heavy-duty nitrous oxides and particulate matter emissions due to Environmental Protection Agency (EPA) regulations has resulted in significant changes to engine hardware since 1998. Such changes have included use of cooled exhaust gas recirculation, clean gas induction, oxidation catalysts, variable geometry turbochargers, lean nitrous oxide traps, urea selective catalytic reduction, passive and catalyzed particulate matter filters, and engine design changes to reduce oil consumption while allowing use of low sulfur diesel fuel (DF-2) and maintaining oil change intervals and subsystem durability levels of previous model years. The net result from a propulsion system perspective is increased heat rejection, additional induction and exhaust system volume, increased system weight, and less tolerance to military fuels and lubricants.

Modern heavy duty Commercial Off The Shelf (COTS) diesel engines represent the state of the art in engine performance and design features, control architecture, and the use of light weight high strength materials. These engines, with appropriate adaptation for operation on military fuels, make excellent choices for defense applications. This paper reviews the selection and modification of a COTS engine suitable for potential defense applications. Considerations for robust operation of the engine on JP8, engine system modifications appropriate for military vehicle emission requirements, reduction of engine system heat rejection, and optimization of engine efficiency will be discussed using example data from converting a 2011 model year COTS engine for defense applications. This work was funded by the Tank Automotive Research, Development and Engineering Center (TARDEC) from Broad Agency Announcement (BAA) Topic 15, awarded in 2009.

Ride control of military vehicles is challenging due to varied terrain and mission requirements such as operating weight. Achieving top speeds on rough terrain is typically considered a key performance parameter, which is always constrained by ride discomfort. Many military vehicles using passive suspensions suffer with compromised performance due to single tuning solution. To further stretch the performance domain to achieving higher speeds on rough roads, semi-active suspensions may offer a wide range of damping possibilities under varying conditions. In this paper, various semi-active control strategies are examined, and improvements have been made, particularly, to the acceleration-driven damper (ADD) strategy to make the approach more robust for varying operating conditions. A seven degrees of freedom ride model and a quarter-car model were developed that were excited by a random road process input modeled using an auto-regressive time series model.

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) phase, 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. In a prior study [16], an extensive parametric study was conducted in a systematic manner so as to create look-up tables or automated software tools that decision-makers can use to quickly estimate the different injury responses for both stroking and non-stroking seat systems in terms of a suitable blast load parameter. The primary objective of this paper is to quantitatively evaluate the accuracy of using such a tool in lieu of building a detailed model for simulation and occupant injury assessment.

Vehicle handing and ride are the critical attributes for customers while buying new passenger vehicle. Hence it is very important to design suspension which meets customer expectations. Often tuning of suspension parameters is very difficult at later stage like wheelbase, vehicle center of Gravity and other suspension parameters like roll center heights etc. A parametric mathematical model is built to study the effect of these parameters of vehicle handling and ride attributes at concept stage. These models are used to calculate the suspension ride rates, spring rates and Anti roll bar diameters for meeting target vehicle ride and handling performance. The model also calculates natural frequency of suspension and vehicle for understanding pitch and roll behaviours.

Investigating the impact of Gasoline fuel on diesel engine performance and emission is very important for military heavy- duty combat vehicles. Gasoline has great potential as alternative fuel due to rapid depletion of petroleum reserves and stringent emission legislations, under multi fuel strategy program for military heavy- duty combat vehicle. There is a known torque, horsepower and fuel economy penalty associated with the operation of a diesel engine with Gasoline fuel. On the other hand, experimental studies have suggested that Gasoline fuel has the potential for lowering exhaust emissions, especially NOx, CO, CO2, HC and particulate matter as compared to diesel fuel. Recent emission legislations also restrict the total number of nano particles emitted in addition to particulate matter, which has adverse health impact.

We have recently obtained experimental data and used them to develop computational models to quantify occupant impact responses and injury risks for military vehicles during frontal crashes. The number of experimental tests and model runs are however, relatively small due to their high cost. While this is true across the auto industry, it is particularly critical for the Army and other government agencies operating under tight budget constraints. In this study we investigate through statistical simulations how the injury risk varies if a large number of experimental tests were conducted. We show that the injury risk distribution is skewed to the right implying that, although most physical tests result in a small injury risk, there are occasional physical tests for which the injury risk is extremely large. We compute the probabilities of such events and use them to identify optimum design conditions to minimize such probabilities.

Design of military vehicle needs to meet often conflicting requirements such as high mobility, excellent fuel efficiency and survivability, with acceptable cost. In order to reduce the development cost, time and associated risk, as many of the design questions as possible need to be addressed with advanced simulation tools. This paper describes a methodology to design a fuel efficient powerpack unit for a series hybrid electric military vehicle, with emphasis on the e-machine design. The proposed methodology builds on previously published Finite element based analysis to capture basic design features of the generator with three variables, and couples it with a model reduction technique to rapidly re-design the generator with desired fidelity. The generator is mated to an off the shelf engine to form a powerpack, which is subsequently evaluated over a representative military drive cycles.

Military vehicles experience a wide range of duty cycles depending on the place and purpose of their deployment. Vehicle fuel consumption directly depends on those use cases, which are ranging from patrolling during peace keeping operations to direct engagements in hostiles areas. Vehicle design should accommodate this wide range of operation modes to maximize the vehicle practicality during their service life. This paper aims to quantify the sensitivity of the powerpack design for a notional 15-ton series hybrid electric vehicle for two highly dynamic military drive cycles. The optimal design for a powerpack (engine coupled with a generator) will be separately determined for each of the use cases through a previously developed optimization routine that use the Genetic Algorithm. For each iteration of the Genetic Algorithm a design benchmarking was incorporated by using Dynamic Programming.

This paper considers optimal power management during the establishment of an expeditionary outpost using battery and vehicle assets for electrical generation. The first step in creating a new outpost is implementing the physical protection and barrier system. Afterwards, facilities that provide communications, fires, meals, and moral boosts are implemented that steadily increase the electrical load while dynamic events, such as patrols, can cause abrupt changes in the electrical load profile. Being able to create a fully functioning outpost within 72 hours is a typical objective where the electrical power generation starts with batteries, transitions to gasoline generators and is eventually replaced by diesel generators as the outpost matures. Vehicles with power export capability are an attractive supplement to this electrical power evolution since they are usually on site, would reduce the amount of material for outpost creation, and provide a modular approach to outpost build-up.