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Unmanned ground vehicles (UGVs) may encounter difficulties accommodating environmental uncertainties and system degradations during harsh conditions. However, human experience and onboard intelligence can may help mitigate such cases. Unfortunately, human operators have cognition limits when directly supervising multiple UGVs. Ideally, an automated decision aid can be designed that empowers the human operator to supervise the UGVs. In this paper, we consider a connected UGV platoon under cyber attacks that may disrupt safety and degrade performance. An observer-based resilient control strategy is designed to mitigate the effects of vehicle-to-vehicle (V2V) cyber attacks. In addition, each UGV generates both internal and external evaluations based on the platoons performance metrics. A cloud-based trust-based information management system collects these evaluations to detect abnormal UGV platoon behaviors.

In this paper, a distributed driver-in-the-loop and hardware-in-the-loop simulator is described with a driver on a motion simulator at the U.S. Army TARDEC Ground Vehicle Simulation Laboratory (GVSL). Realistic power system response is achieved by linking the driver in the GVSL with a full-sized hybrid electric power system located 2,450 miles away at the TARDEC Power and Energy Systems Integration Laboratory (P&E SIL), which is developed and maintained by Science Applications International Corporation (SAIC). The goal is to close the loop between the GVSL and P&E SIL over the Internet to provide a realistic driving experience in addition to realistic power system results. In order to preserve a valid and safe hardware-in-the-loop experiment, the states of the GVSL must track the states of the P&E SIL.

A long-distance microscope with pulse-laser as optical shutter up to 25kHz was used to magnify the diesel spray at the nozzle hole vicinity onto 35-mm photographic film through a still or a high-speed drum camera. The injectors examined are high-pressure valve-covered-orifice (VCO) nozzles, from unit injector and common rail injection systems. For comparison, a mini-sac injector from a hydraulic unit injector is also investigated. A phase-Doppler particle analyzer (PDPA) system with an external digital clock was also used to measure the droplet size, velocity and time of arrival relative to the start of the injection event. The visualization results provide very interesting and dynamic information on spray structure, showing spray angle variations, primary breakup processes, and spray asymmetry not observed using conventional macroscopic visualization techniques.

There is evidence to suggest that before military equipment ever experiences sustainment delays the equipment carries state patterns within its logistics and supply chain data history that could be leveraged for risk mitigation. Analysis of these patterns can also identify new research & development (R&D) and technology transition candidates that relate the seemingly disparate activities of R&D project management and Diminishing Manufacturing Sources and Material Shortages (DMSMS) management. Relating eligible R&D activities to the DMSMS risk identification phase helps stage potential sustainment risk mitigations ahead of time on the one hand, while creating additional demand and resources to mature prototypes on the other hand.

Experimental results focused towards developing tribological surface coatings coupled with liquid lubricant boundary layer effects, for advanced high temperature military diesel engine applications are presented. The primary focus of this work is in the area of advanced, low heat rejection (LHR) high output diesel engines, where high temperature boundary lubrication between the piston ring and the cylinder liner wall surface is critical for successful engine operation. The target temperature focused upon in our research is an operating top ring reversal (TRR) temperature of approximately 538°C. The technology advancement used for this application involves treating porous iron oxide/titanium oxide (Fe2O3/TiO2) and molybdenum (Mo) based composite thermal sprayed coatings with chemical binders to improve coating strength, integrity, and tribological properties. This process dramatically decreases open porosity to form an almost monolithic appearing coating at the surface1.

Tank Automotive Research, Development, and Engineering Center (TARDEC) researched flame, smoke, and toxicity requirements for energy attenuating (EA) materials for use in U.S. Army Ground System Vehicle (GSV) applications. The purpose of this project is to reduce secondary thermal injury as a result of introducing EA materials into the military vehicle’s interior. Commercial-off-the-shelf materials were evaluated for their flame, smoke, and toxicity performance using three American Society for Testing and Materials (ASTM) standards: ASTM E1354, ASTM E162, and ASTM E162. The results of this effort identified solutions which may potentially meet the needs of the Army’s unique thermal environment. TARDEC used the knowledge gained from this project to create performance specification requirements for interior head impact protective materials for us in U.S. Army vehicles.

This paper discusses the evolution of skid steer systems, and takes a new look at the advantages and implications of designing future ground combat vehicles with all non-steerable wheels. The traditional “skid steer” designation of such vehicles is dropped in favor of the more descriptive phrase “differential torque steer” vehicle. The possible advantages of such systems for combat vehicle application are presented along with a synopsis of various past modeling, simulation, and vehicle hardware efforts to evaluate skid steer systems. A comprehensive vehicle modeling effort for a differential torque steer system is then presented. Two independent implementations of the model are presented along with model verification and validation results. Finally the model is used to evaluate potential turning performance for a 4×4 vehicle with differential torque steer.

The paper presented herein, combines various aspects of hybrid electric powertrain technology with the mechanics of multi-axle drivelines. Starting with a review of why automotive engineers desire to implement electrified powertrain technology, the paper will then explore the reasons for multi-axle drivetrains and finally, will explore the benefits and challenges of combining hybrid-electric and multiaxle driveline technology.

The U.S. Army utilizes both world wide available diesel fuel and jet fuel (JP-8) for ground mobility applications and must maintain such fuel flexibility in order to meet mission requirements. Understanding of combustion system sensitivity to JP-8 is not well documented for such vehicle applications and thus the current knowledge base on standard diesel spray combustion must be extrapolated in order to assess fuel effects on military combustion systems. In particular, the liquid length of developed, high pressure fuel sprays is a key combustion affecting parameter that is sensitive to fuel type, the fuel delivery system, and combustion chamber thermodynamic condition. This parameter provides targeting information that is employed for assessing bulk jet mixing, cylinder pressure rise (evaporation rate), jet-wall interaction, and the formation of nitrous oxide and particulate matter.

The design of vehicles increasingly challenges existing cost, weight, durability, and handling regimes. This challenge is further compounded by pressure to decrease or limit the duration of the design cycle. The simulation of vehicle dynamic behavior commonly applies just rigid, or better rigid and linear flexibility models to predict motions and determine load cases. However, as the boundaries of materials are pushed these are becoming insufficient to accurately predict behavior. Alternatively, complete nonlinear finite element representations of vehicle dynamics are always possible but are presently infeasible for the support of a single design under virtual test, not to mention several design iterations. To address these issues, a novel abstract multi-rate simulation method is outlined which is designed to exploit the richness of available model in the vehicle dynamics domain.

The objective of this work is to develop a strategy to reduce the penalties in the diesel engine performance, fuel economy and HC and CO emissions, associated with the operation in the low temperature combustion regime. Experiments were conducted on a research high speed, single cylinder, 4-valve, small-bore direct injection diesel engine equipped with a common rail injection system under simulated turbocharged conditions, at IMEP = 3 bar and engine speed = 1500 rpm. EGR rates were varied over a wide range to cover engine operation from the conventional to the LTC regime, up to the misfiring point. The injection pressure was varied from 600 bar to 1200 bar. Injection timing was adjusted to cover three different LPPCs (Location of the Peak rate of heat release due to the Premixed Combustion fraction) at 10.5° aTDC, 5 aTDC and 2 aTDC. The swirl ratio was varied from 1.44 to 7.12. Four steps are taken to move from LTC to ALTC.