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The authors present the supervisory control of a parallel hybrid powertrain, focusing on several issues related to the real-time implementation of optimal control based techniques, such as the Equivalent Consumption Minimization Strategies (ECMS). Real-time implementation is introduced as an intermediate step of a complete chain of tools aimed at investigating the supervisory control problem. These tools comprise an offline optimizer based on Pontryagin Minimum Principle (PMP), a two-layer real-time control structure, and a modular engine-in-the-loop test bench. Control results are presented for a regulatory drive cycle with the aim of illustrating the benefits of optimal control in terms of fuel economy, the role of the optimization constraints dictated by drivability requirements, and the effectiveness of the feedback rule proposed for the adaptation of the equivalence factor (Lagrange multiplier).

Compliance with tighter emission regulations has increased the proportion of parasitic weight in commercial vehicles. In turn, the amount of payload must be reduced to comply with transportation weight requirements. A re-design of commercial vehicle components is necessary to decrease the vehicle weight and improve payload capacity. Side rails have traditionally been manufactured from high strength steels, but significant weight reductions can be achieved by substituting steel side rails with 6013 high strength aluminum alloy side rails. Material and stress analyses are presented in this paper in order to understand the effect of manufacturing process on the material's mechanical behavior. Metallographic and tensile test experiments for the 6013-T4 alloy were performed in preparation for residual stress measurements of a punching operation. Punched holes are critical to the function of the side rail and can lead to high stress levels and cracking.

The ride dynamics of typical North-American soil compactors were investigated via analytical and experimental methods. A 12-degrees-of-freedom in-plane ride dynamic model of a single-drum compactor was formulated through integrations of the models of various components such as driver seat, cabin, roller drum and drum isolators, chassis and the tires. The analytical model was formulated for the transit mode of operation at a constant forward speed on undeformable surfaces with the roller vibrator off. Field measurements were conducted to characterize the ride vibration environments during the transit mode of operation. The measured data revealed significant magnitudes of whole-body vibration of the operator-station along the vertical, lateral, pitch and roll-axes. The model results revealed reasonably good agreements with ranges of the measured vibration data.

With the growing environmental concerns, biodegradable materials are gaining more importance. Biocomposites which are made from a combination of biological fiber such as flax and hemp together with plastics are finding a good number of applications in day to day life. Flax has good physical and mechanical properties that can be utilized in areas like construction, biomedical & bioproducts and electronics applications. The quality of fiber depends upon various unit operations used in the processing. Drying is one of the most important unit operations which significantly affect the quality of the fiber. The method of drying for removal of moisture from the fiber significantly affects the drying time and quality. In the present study the raw flax fiber was subjected to drying before and after chemical treatment. The physical properties such as; tensile strength, color and structural changes were measured for raw and chemically treated flax fibers.

The research on using natural fibres as the reinforcement in plastic composites has increased dramatically in the last few years. Flax fibres are renewable resources with low specific mass, reduced energy consumption, and relatively low in cost. These advantages make flax fibres recognized as a potential replacement for glass fibres in composites. Among plastic, polyethylene was concluded to be a suitable material used as matrix in natural fibre reinforced biocomposites. However there are few studies on this area so far. In this paper, the processing method of flax fibre-reinforced polyethylene biocomposites is introduced. Flax fibre polyethylene biocomposite consists of flax fibre as the reinforcing component and high density polyethylene as the matrix. Acrylic acid pre-treatment was applied to flax fibre to improve the bonding between fibre and polyethylene.

Modern diesel Fuel Injection Equipment (FIE) systems are susceptible to the formation of a variety of deposits. These can occur in different locations, e.g. in nozzle spray-holes and inside the injector body. The problems associated with deposits are increasing and are seen in both Passenger Car (PC) and Heavy Duty (HD) vehicles. Mechanisms responsible for the formation of these deposits are not limited to one particular type. This paper reviews FIE deposits developed in modern PC and HD engines using a variety of bench engine testing and field trials. Euro 4/ IV and Euro 5/V engines were selected for this programme. The fuels used ranged from fossil only to distillate fuels containing up to 10% Fatty Acid Methyl Ester (FAME) and then treated with additives to overcome the formation of FIE deposits.

The enactment of FMVSS 126 requires specific safety performance in vehicles 4,536 Kg (10,000 pounds) or less using an Electronic Stability Control (ESC) system as standard equipment by 2011. Further, in 2012, the regulation requires vehicles that have undergone aftermarket modification to remain in compliance with the performance standard. This paper describes: • a brief overview of the standard and its implications • the collaborative approach used in the first successful approach in meeting that requirement by a lift kit manufacturer o a Hardware In the Loop (HIL) test alternative for establishing a reasonable expectation for a vehicle to demonstrate compliance after modification. • Collaborative challenges overcome: o aftermarket manufacturers seeking information sharing with OEMs and Tier One suppliers: o respecting the intellectual property of OEMs and Tier One suppliers o maintaining the integrity between tool competitors and their customers in cross-collaborative efforts

Dynamic and quasi-static axial cutting of circular AA6061-T6 extrusions with variable instantaneous wall thickness in the axial direction was completed to investigate the capability of controlling the load/displacement responses of the extrusions. Circular specimens considered for this research had an original nominal wall thickness of 3.175 mm, an external diameter of 50.8 mm, and a tube length of 300 mm. Variations of the wall thickness were completed by material removal of the extrusions using a CNC machine. Specially designed cutters having a block height of 20 mm, a blade tip width of 1.0 mm and a blade shoulder width of 3.0 mm were employed to generate the axial cutting deformation mode. Either one or two cutters were selected to initiate a single or dual cutting deformation. A curved deflector with a profile radius of 50.8 mm was used to flare the cut petalled sidewalk and facilitate the cutting system.

In this paper, the microstructure-based finite element modeling method is used in investigating the loading path dependence of formability of transformation induced plasticity (TRIP) steels. For this purpose, the effects of different loading path on the forming limit diagrams (FLD) of TRIP steels are qualitatively examined using the representative volume element (RVE) of a commercial TRIP800 steel. First, the modeling method was introduced, where a combined isotropic/kinematic hardening rule is adopted for the constituent phases in order to correctly describe the cyclic deformation behaviors of TRIP steels during the forming process with combined loading paths which may include the unloading between the two consecutive loadings. Material parameters for the constituent phases remained the same as those in the authors' previous study [ 1 ] except for some adjustments for the martensite phase due to the introduction of the new combined hardening rule.

Predicting AHSS cracking during crash events and forming processes is an enabling technology for AHSS application. Several fracture criteria including MatFEM and Modified Mohr-Coulomb Criterion were developed recently. However, none of them are designed to cover more fracture modes such as bending fracture and tearing fracture with initial damage. A mixed-mode fracture criterion (MMFC) is proposed and developed to capture multiple fracture modes including in-plane shearing fracture, cross-thickness shearing fracture with bending effect and tearing fracture with initial damage. The associated calibration procedure for this criterion is developed. The criterion is implemented in a commercial FEA code and several lab validations are conducted. The results show its promising potential to predict AHSS cracking at large strain conditions.

Neutron diffraction is a powerful tool that can be used to identify the phases present and to measure the spacing of the atomic planes in a material. Thus, the residual stresses can be determined within a component and/or the phases present. New intercritically austempered irons rely on the unique properties of the austenite phase present in their microstructures. If these materials are to see widespread use, methods to verify the quality (behavior consistency) of these materials and to provide guidance for further optimization will be needed. Neutron diffraction studies were performed at the second generation neutron residual stress facility (NRSF2) at the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory on a variety of intercritically austempered irons. For similar materials, such as TRIP steels, the strengthening mechanism involves the transformation of metastable austenite to martensite during deformation.

Magnesium and aluminum alloys offer lightweighting opportunities in automotive applications. Joining of dissimilar materials, however, generally requires methods that do not involve fusion. This paper explores the use of self-pierce riveting (SPR) to join magnesium to aluminum alloys for structural and closure applications. The preliminary results indicate that SPR is a viable option for joining aluminum extrusions to magnesium die castings, as well as stamped sheet aluminum to quick-plastic-formed (QPF) sheet magnesium.

Experimental decklids for the Cadillac STS sedan were made with Al AA5083 sheet outer panels and Mg AZ31B sheet inner panels using regular-production forming processes and hardware. Joining and coating processes were developed to accommodate the unique properties of Mg. Assembled decklids were evaluated for dimensional accuracy, slam durability, and impact response. The assemblies performed very well in these tests. Explicit and implicit finite element simulations of decklids were conducted, and showed that the Al/Mg decklids have good stiffness and strength characteristics. These results suggest the feasibility of using Mg sheet closure panels from a structural perspective.

The Michelin Tweel tire structure has recently been developed as an innovative non-pneumatic tire which has potential for improved handling, grip, comfort, low energy loss when impacting obstacles and reduced rolling resistance when compared to a traditional pneumatic tire. One of the potential sources of vibration during rolling of a non-pneumatic tire is the buckling phenomenon and snapping back of the spokes in tension when they enter and exit the contact zone. Another source of noise was hypothesized due to a flower petal ring vibration effect due to discrete spoke interaction with the ring and contact with the ground during rolling as the spokes cycle between tension and compression. Transmission of vibration between the ground force, ring and spokes to the hub was also considered to be a significant contributor to vibration and noise characteristics of the Tweel.

In Chemistry “Inert” implies ‘not readily reactive with other elements; forming few or no chemical compounds or something that is not chemically active’. “Inerting” is the process that renders a substance inert. A method for making a fuel-tank inert without the use of an inert gas is described. In this method fuel-air ratio of ullage is reduced until it becomes inert. The method does not discharge fuel vapors as an inert gas inerting system. Two systems employing the method are described explaining their pros and cons. Advantages of the method over Nitrogen Enriched Air (NEA) inerting method with an On-board Inert Gas Generating System (OBIGGS) are discussed. Patent application on the method and system is pending.

Boeing has contracts for military application of twin engine airplanes generically identified in this paper as the MX airplane. Unlike previous derivatives, the MX airplanes are produced with a streamlined manufacturing process to improve cost and schedule performance. The final assembly of each MX airplane includes a series of integration tests, called factory functional tests (FFTs), which are modified from those of typical commercial versions and verify correctness of equipment installation and basic functionalities. Two airplanes have been through the production line resulting in a number of FFT lessons learned. Addressed are the power distribution lessons learned: 1) the expanded coverage of the basic automated power-on generation system test, 2) the need for a manual wire continuity test, 3) salient features of the power distribution tests, and 4) keys to make first pass power distribution test smooth and successful.

Dimensional variation simulation is a computer aided engineering (CAE) method that analyzes the statistical efforts of the component variation to the quality of the final assembly. The traditional tolerance analysis method and commercial CAE software are often based on the assumptions of the rigid part assembly. However, the vehicle functional attributes, such as, ride and handling, NVH, durability and reliability, require understanding the assembly quality under various dynamic conditions while achieving vehicle dimensional clearance targets. This paper presents the methods in evaluating and analyzing the impacts of the assembly variations for the vehicle dynamic performance. Basic linear tolerance stack method and advanced study that applies various CAE tools for the virtual quality analysis in the product and process design will be discussed.

Extended-duration space missions entailing expanded crew sizes and activities will produce a need for habitats that combine advantages of conventional hard/fixed and soft/deployable structures. Rigid modules enable pre-integration of utility and equipment systems prior to launch and apply proven technologies. Soft pressure vessels can be compacted to optimize launch payload volume and habitable volume/mass efficiencies, but impose hardware integration challenges, operational readiness requirements, and long-term structural performance uncertainties. This paper discusses concepts and applications that incorporate both approaches. Examples draw upon research and design investigations undertaken by SICSA in support of a NASA-sponsored study conducted by two independent teams, one headed by Boeing, and the other by ILC-Dover. SICSA had key roles in developing overall configuration architectures for both teams.

Research has been conducted on an extended expansion engine, using a multiple linkage system to increase the thermal efficiency of general-purpose engines. In this research, first, the test engine was subjected to an engine acoustics measurement to clarify its noise characteristics. Then, based on the analysis results of the noise characteristics, we propose the direction to reduce the noise of the multiple linkage system engine. When the test engine was operated under a no-load firing condition, rattle noise was observed. Also it was found that the timing of the occurrence of the rattle noise was near after top dead center (ATDC) 90 degrees in crank angle (degCA). Focusing on the gear for linkage drive as a cause of the rattle noise, the authors formulated the torque acting on the gear.

The paper aims at performing an environmental and energetic optimization of a naturally aspirated, light-duty direct injection (DI) diesel engine, equipped with a Common Rail injection system. Injection modulation into up to three pulses is considered starting from an experimental campaign conducted under non-evaporative conditions in a quiescent optically-accessible cylindrical vessel containing nitrogen at different densities. The engine performances in terms of power and emitted NOx and soot are reproduced by multidimensional modelling of the in-cylinder processes. The radiated noise is evaluated by resorting to a recently developed methodology, based on the decomposition of the CFD 3D computed in-cylinder pressure signal. Once validated, both the CFD and the acoustic procedures are applied to the simulation of the prototype engine and are coupled to an external optimizer with the aim of minimizing fuel consumption, pollutant emissions and radiated noise.