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A Hybrid Projectile (HP) is a ballistically launched round that transforms into an Unmanned Aerial Vehicle (UAV) at a designated point during flight. Aerodynamic control surfaces and associated control laws were sought that would extend the projectile's range using body lift and include guidance for a selected point of impact. Several challenges were encountered during the modification of an existing projectile, in this case a 40mm round, to achieve range extension and controllability. The control surfaces must be designed to allow for de-spin, controllability, and natural static stability. Also, a control system with laws and guidance relationships between heading, pitch or glide rate, and the associated aerodynamic surface movements needed to be developed. The designed aerodynamic surfaces, external ballistics, and control methods developed were modeled in a projectile flight simulator built in MATLAB.

Diesel Particulate Filters (DPFs) are well assessed exhaust aftertreatment devices currently equipping almost every modern diesel engine to comply with the most stringent emission standards. However, an accurate estimation of soot content (loading) is critical to managing the regeneration of DPFs in order to attain optimal behavior of the whole engine-after-treatment assembly, and minimize fuel consumption. Real-time models can be used to address challenges posed by advanced control systems, such as the integration of the DPF with the engine or other critical aftertreatment components or to develop model-based OBD sensors. One of the major hurdles in such applications is the accurate estimation of engine Particulate Matter (PM) emissions as a function of time. Such data would be required as input data for any kind of accurate models. The most accurate way consists of employing soot sensors to gather the real transient soot emissions signal, which will serve as an input to the model.

Recent advances in Metal Matrix Composites have made them ready for transition to large-volume production and commercialization. Such new materials seem to allow the fabrication of higher quality parts at less than 50 percent of the weight as compared to steel. The increasing requirements of weight savings and extended durability motivated the potential application of MMC technology into the heavy vehicle market. However, significant technical barriers such as joining are likely to hinder the broad applications of MMC materials in heavy vehicles. The focus of this paper is to examine the feasibility of manufacturing and the behavior of bolted joint connections made from aluminum matrix reinforced with Silicon Carbide (SiC) particles. Two reinforcement ratios: 20% and 45% were considered in this study. The first part of the paper concentrates on experimental evaluation of bolted MMC joints.

This paper presents results from a study on speciation of the emission profiles and on the ozone forming potential of heavy-duty diesel exhaust under steady state engine operation. Very limited attempts have been made at determining the ozone forming potential of heavy duty diesel exhaust emissions. In this study a proportional sample of the dilute exhaust was drawn from a CFV-CVS system using a temperature controlled sampling line. The particulate matter was collected on a 70 mm Teflon coated glass fiber filter (TX40HI20WW), the semi-volatiles on XAD-2 copolymer resin and volatiles in Tedlar bags. The samples were analyzed by gas chromatography after conditioning and chemical extractions. The initial phase of the study was directed towards developing techniques and establishing protocols to determine the ozone forming potential of heavy-duty diesel exhaust. A pre-chamber naturally aspirated engine was tested on steady-state modes 1, 3, 5, 7 and 8 of the ISO 8 mode cycle.

With the implementation of a closed loop fuel control system, operation of lean-burn natural gas engines can be optimized in terms of reducing emissions while maximizing efficiency. Such a system would compensate for variations in fuel composition, but also would correct for variations in volumetric efficiency due to immediate engine history and long-term engine component wear. Present day engine controllers perform well when they are operated with the same gas composition for which they were calibrated, but because fuel composition varies geographically as well as seasonally, some method of compensation is required. A closed loop control system on a medium-duty lean-burn engine will enhance performance by maintaining the desired air-fuel ratio to eliminate any unwanted rich or lean excursions (relative to the desired air-fuel ratio) that produce excess engine-out emissions. Such a system can also guard against internal engine damage due to overheating and/or engine knock.

A family of transmission systems based on a “Planetary Gear - CVT” mechanism is presented here. The systems considered consist of two compound planetary gear trains connected through a CVT pulley system to provide the power/torque split and recirculation function, without the use of additional clutches and/or chain drives. A two degree of freedom system results in which one of the degrees of freedom is directly related to the CVT ratio. The mechanisms considered here combine the gear reduction function of compound planetary gear trains with the continuously variable trans- used as a circulating power control unit. The kinematics and dynamics of this family of systems is presented with emphasis on the belt forces, torques on the various shafts and the overall input/output velocity ratios through the CVT ratio span. Then a parametric analysis is conducted to characterize the effect of the various functional ratios and parameters of the system in terms of the overall performance.