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The aim of this work is to apply an innovative adaptive ℒ1 techniques to control flutter phenomena affecting highly flexible wings and to evaluate the efficiency of this control algorithm and architecture by performing the following tasks: i) adaptation and analysis of an existing simplified nonlinear plunging/pitching 2D aeroelastic model accounting for structural nonlinearities and a quasi-steady aerodynamics capable of describing flutter and post-flutter limit cycle oscillations, ii) implement the ℒ1 adaptive control on the developed aeroelastic system to perform initial control testing and evaluate the sensitivity to system parameters, and iii) perform model validation and calibration by comparing the performance of the proposed control strategy with an adaptive back-stepping algorithm. The effectiveness and robustness of the ℒ1 adaptive control in flutter and post-flutter suppression is demonstrated.

An integrated simulation tool has been developed, which is applicable to a wide range of design issues. A key feature introduced for the first time by this new tool is that it is truly a single code, with identical handling of engine, powertrain, vehicle, hydraulics, electrical, thermal and control elements. Further, it contains multiple levels of engine models, so that the user can select the appropriate level for the time scale of the problem (e.g. real-time operation). One possible example of such a combined simulation is the present study of engine block vibration in the mounts. The simulation involved a fully coupled model of performance, thermodynamics and combustion, with the dynamics of the cranktrain, engine block and the driveline. It demonstrated the effect of combustion irregularity on engine shaking in the mounts.

A line of five new row-crop tractors is being introduced by John Deere with innovative features including a 15-speed full power shift transmission, a high capacity, highly-maneuverable full-time mechanical front-wheel drive and micro-processor controlled instrumentation. In addition, the tractors have increased power, improved fuel economy, greater hydraulic power, improved hitch sensing, improved operator controls, lower sound levels, and revised styling. This paper documents the design and development of these new John Deere row-crop tractors.

Fuel economy can be part of a business case for a fleet making the decision to buy new HD hybrid drivetrain technologies. Chassis dynamometer tests using SAE Recommended Practice J2711 on a bus equipped with an Allison EP SYSTEM ™ hybrid system and operated on standard bus driving cycles have produced impressive gains of over 60%. Preliminary urban bus field tests, on the other hand, have shown lower fuel economy gains. The difference can be attributed, in part, to the use of accessories - most importantly air conditioning - which are parasitic loads on the vehicle. In this paper the characteristics of driving cycles are studied to determine those factors which have the strongest influence on fuel economy for hybrids. The data show that the number of stopping events in a route or cycle is a strong influence as is the average vehicle speed. Energy analysis will show the relationship of fuel economy benefit and battery energy within a driving cycle.

Understanding customer expectations is critical to satisfying customers. Holding customer clinics is one approach to set winning targets for the engineering functional measures to drive customer satisfaction. In these clinics, customers are asked to operate and interact with vehicle systems or subsystems such as doors, lift gates, shifters, and seat adjusters, and then rate their experience. From this customer evaluation data, engineers can create customer loss or preference functions. These functions let engineers set appropriate targets by balancing risks and benefits. Statistical methods such as cumulative customer loss function are regularly applied for such analyses. In this paper, a new approach based on the Taguchi method is proposed and developed. It is referred to as Taguchi Customer Loss Function (TCLF).

TFC/IW, total fuel consumption divided by inertia weight is reported with other engineering variables for recent EPA data for industry passenger cars and truck. TFC/IW is used in comparisons between gasoline and diesel engines, 49 States and California, passenger cars and trucks. The California fuel economy penalty due to more stringent emissions standards is discussed. The relationship between TFC/IW and ton miles per gallon is shown. Special attention is focused on 4 cylinder gasoline powered vehicles in 49 States passenger car fleet. The use of TFC/IW to answer the question, ‘What Changed?’ when comparing the fuel economies of two fleets is described.

High performance lubricant additive systems have been developed to formulate SAE 5W-30 passenger car engine oils which meet current and anticipated requirements of the North American original equipment manufacturers. The trend in North America is to recommend SAE 5W-30 oils that not only meet the API SF requirements for gasoline engines (“first-generation” oils), but also meet the stringent API CC requirement for light duty diesel engines (“second-generation” oils). Furthermore, the engine builders have issued “world specifications” for motor oils which incorporate additional “second-generation” SAE 5W-30 characteristics, such as enhanced API SF limits, improved fuel efficiency, an increased margin of bearing protection, and lower finished-oil phosphorus levels. The additive systems described herein exceed API SF and CC requirements as well as “second-generation” performance hurdles.

The SHIFT-MATE is a dashboard mounted computer based device that cues a truck driver to shift more efficiently. Through electronic circuitry, key vehicle parameters are monitored, computed, then via graphic display, instructs the driver when to shift for improved fuel economy. The theory of operation is described in the text.

Estimation of soot deposited on a wall flow type DPF, is a vital information to ensure safe and efficient DPF management. Accuracy in determining mass of soot present inside the DPF ensures a correct regeneration management strategy in-terms of fuel efficiency and DPF safety considering soot overloading and too frequent regenerations. It also ensures an efficient detection of anomalies in the PM filtration mandated by the BSVI/EURO VI legislation as a part of On-board diagnostics. Classical approach of determining soot present inside DPF involves monitoring increase in pressure drop. Real time usage of such a model is limited by the inaccuracy of measuring pressure drop at low exhaust flows. Hence, contemporary engine controllers use pressure drop based models as a failsafe and estimate DPF soot loading by modelling soot release rate due to engine combustion and the rate at which it is oxidized.

The simulation system “Roadrunner” has the ability to compute 3-dimensional vehicle behavior during simulated ABS-stops or Traction Control (TC) operation on a PC based test rig system. This can be done in real-time mode with fast DSP (digital signal processor) boards and an ABS/TC-ECU as a ‘Hardware-in-the-loop’ device (HIL) or off-line (non-real-time), on the PC only. In the off-line-mode, the PC additionally performs the ABS/TC control algorithms. The simulated system includes model equations for chassis and wheel movement, hydraulics and road to tire interactions. A driver model enables the reproduction of standard steering maneuvers.

This paper presents a fatigue criterion based on stress invariants for the frequency-based analysis of multiaxial random stresses. The criterion, named “Projection-by-Projection” (PbP) spectral method, is a frequency-based reformulation of its time-domain definition. In the time domain PbP method, a random stress path is first projected along the axes of a principal reference frame in the deviatoric space, thus defining a set of uniaxial random stress projections. In the frequency-domain approach, the damage of stress projections is estimated from the stress PSD matrix. Fatigue damage of the multiaxial stress is next calculated by summing up the fatigue damage of every stress projection. The criterion is calibrated on fatigue strength properties for axial and torsion loading. The calculated damage is shown to also depend on the relative ratio of hydrostatic to deviatoric stress components.

This paper describes the initial works related to the study of Internal Combustion Engines, as an object of mechanical design, at the Universidad Tecnológica de Pereira. It is reported a concise, complete methodology for simple model of internal combustion engine. The emphasis of the paper is placed on the use of the in-cylinder parameters (pressure and temperature) and inertial loads in the crank-slider mechanism to derive the loads that act on all the components of the crank-slider mechanism as well as the theoretical output torque for a given geometrical structure and inertial properties. These loads can then be used to estimate the preliminary dimensions of engine components in the initial stage of engine development. To obtain the pressure and temperature inside the cylinder, under different operation parameters, such as air fuel ratio and spark angle advance, a Zero dimensional model is applied. The heat transfer from the cylinder and friction are not taken into account.

The ability to carry cargo efficiently in passenger aircraft has influenced airline economics to the point that optimisation of the freight capacity is mandatory. This document discusses the alternative loading possibilities in defined Lover Deck Compartments and their doors to cater for current and future trends in ULD dimensions. As a result items for study centred on: 1) Optimisation of the available volumes Freight capacity resulting in the selection of “Pallets”-doors for both the Forward and AFT Compartments. Flexibility to meet Freight and Baggage requirements. Possible load arrangements to optimize aircraft C of G 2) Bulk Cargo Compartment Additional LD3 Container position in AFT/Bulk compartment to cater for an uneven number of Baggage container, allowing the carriage of an additional pallet. What is regarded as an optimum is presented.

Advanced diesel engines developed for the commercial market need to be adapted to the military requirements by OPERAS (Optimizing the injection pressure P, the Exhaust gas recirculation E, injection events Retard and/or Advance and the swirl ratio S). The different after treatment devices, already used or expected to be applied to diesel engines, require feed gases of appropriate properties for their efficient operation. To produce these gases some OPERAS are needed to control the diesel combustion process. Since military vehicles do not need the after treatment devices, the OPERAS of the commercial engines should be modified to meet the military requirements for high power density, better fuel economy, reduction of parasitic losses caused by the cooled EGR system, and reduction of invisible black and white smoke in the field.

Presented in this paper is a brief review of momentum exchange theory for Jet Noise Suppression. “Experimental Results from Scale Model Tests” are included. These data exhibit peak to peak attenuation of 20 db along maximum exhaust noise azimuths at a nozzle pressure ratio of 3.1.

Vehicle dynamics is a discipline of mechanical engineering that benefited of significant improvements thanks to the progress of computational engineering. Vehicle dynamics engineers are using CAE for the development of a vehicle with MBS and FEA. The concurrent use of these two technologies is a standard in the automotive industry. However the current simulation process is not fully efficient because local geometrical and material nonlinearities are not accurately modeled in classical MBS software. This paper introduces a methodology for vehicle dynamics simulation integrating MBS capabilities in one single nonlinear FEA environment enabling an accurate modeling of nonlinearity in vehicles.

Mathematical modeling and control of artificial ecosystems, such as MELISSA, require first the study of physical and biological characteristics in optimal and limiting conditions. Following the previous determination of the stoichiometric equations (Spirulina compartment) and regarding the two phototrophic compartments of MELISSA (Rhodospirillaceae and Spirulina), we have first to focus our control study on the growth kinetics for the light source. In this paper, we recall the theoretical equations of microbial growth kinetics and emphasise the problem of the light transfer in a photobioreactor. We present their adaptations to our pilot plant taking into account technological and biological specifics (lamp spectrum, working illuminated volume, growth rate,…). We then develop the principles and structure of the control system and describe tests of both the hardware and software for several steady state configurations.

This paper describes the application of statistical techniques known as Design of Experiments (D.O.E.) to efficiently use the results of numerical analysis data in order to improve the configuration of automotive systems. The general framework of these techniques is presented in a format aiming at the design engineer as their end user. Besides, a case study is presented with the purpose of illustrating their practical use. The first step of the case study is to build predictive models for the behaviour of the automotive system being developed by means of the Response Surface Method (RSM), using the proper D.O.E. options. Once these predictive models are available, automatic numerical optimization algorithms are used to improve the responses of interest for given operating conditions. Finally, the automotive systems are robust designed taking into account that the operating conditions vary randomly.

Due to ever soaring fuel costs and even more stringent emission regulations which require more elaborate technical efforts and unfortunately lead to a negative trend on fuel economy as well, todays and future trucking business is extremely challenged. These facts create an urgent requirement for the engine manufacturer to offer an engine with an optimized cost-benefit-ratio for the trucking business. Mercedes-Benz, as the leader in the European commercial vehicle market - of which e. g. high fuel costs, long maintenance intervals and high engine power-to-weight ratios have always been key characteristics - has developed a new class 8 engine for the US market. The MBE 4000 is a 6 cylinder inline engine in the compact size and low weight category, but due to its displacement of 12,8 liters it offers high performance characteristics like heavier big block engines.

A lithium ion battery system has been developed for use in Honda's FCX Clarity fuel cell vehicle. This represents the first time that Honda has employed lithium ion batteries. The battery system equals the high level of power of the ultracapacitor system used in the previous FCX vehicle but achieves a higher level of energy, contributing to various improvements in performance, such as the Clarity's superior acceleration feel and improved fuel efficiency. The system displays sufficient durability and reliability at the same time as satisfying requirements from the perspective of safety. In addition, positioning the battery system under the floor of the vehicle has increased cabin space, boosting the Clarity's commercial appeal.