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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.

A Web-based version of the aircraft design program ACSYNT has been created. “Web-ACSYNT” provides the user with a familiar user interface and is accessible from multiple platforms. Analyses are based upon a set of baseline aircraft models which can be modified through a carefully selected set of parameters related to weight, aerodynamics, propulsion, economics, and mission. The software is intended to become one of the models that comprise the Aviation System Analysis Capability (ASAC) currently being developed by NASA under the Advanced Subsonic Technology (AST) program.

This paper demonstrates the possibilities of using Automotive waste plastic material from “end of life” vehicles (ELVs), in the Footwear Industry to manufacture shoe components. The study establishes the sustainability of the flow of ELVs, from the European Car Parc and identifies and estimates the quantity of plastic materials potentially available for recycling from ELVs. Four potential materials, Acrylonitrile/butadiene/styrene (ABS), Polypropylene (PP), Polypropylene/ethylene/propylene/diene (PP/EPDM) and Polyamide (PA), were identified and three materials (PP, PP/EPDM and ABS) were reprocessed from ELV components and evaluated by the Footwear Industry. As a result, ABS was recommended as an economically, suitable replacement for HIPS, the current material used for manufacturing shoe heel components.

A program was developed that provides a user friendly interface for developing and testing shift tables in a powershift transmission. This program is Windows based and runs on an IBM compatible P.C. When coupled with a suitable controller, transmission designers have a useful tool for the development of transmission shift timing. The system is designed to be used in an engine test cell or for actual vehicle tests. This allows the vehicle operator to call up and edit shifts on a P.C. screen and then drive the vehicle using the new shifts. This allows the operator to evaluate results of real time shifts immediately.

Countless articles and publications3,4,5 have documented and proven the efficacy, benefits and value of operating within a lean system. Furthermore, there exists common agreement amongst leading organizations successfully implementing a lean system that in order to do so it must take into consideration the entire enterprise, that is, from supplier to customer and everything in between6. One of the core issues this paper addresses is when the optimal time is to train and educate the people who currently have, or will have, influence over the ‘enterprise’.

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).

Pneumatic, manually operated, drilling machines are used to produce a significant proportion of all holes drilled during wing manufacture. Drilling machine design and the manual drilling process has not changed significantly in decades. By employing miniature, low power, electronics and interfacing techniques, a monitoring system has been developed. This system enables improved process control of the manual drilling operation. Machine calibration management, measurement of drill performance, jig drilling error control and asset management are some of the benefits attainable. This project will hopefully encourage others to discover the potential for improving historically established processes, by employing modern technological developments.

This paper presents, chemistry, test data and processing procedures on a non toxic and environmentally friendly chrome-free conversion coating alternative with the same level of adhesion and secondary corrosion resistance as that found in chrome containing conversion coating systems. Test data from military and independent sources will be presented on secondary coating adhesion, electrical conductivity, filiform and neutral salt-spray corrosion resistance as compared to chromate based systems .on magnesium, aluminum and zinc and their respective alloys. The European “RoSH” initiative will not allow for the presence of any hexavalent chromium on imported electrical components as of July first of 2006. Trivalent chromium based systems generate hexavalent chromium due to the oxidation of the trivalent chromium and as such will not be allowed.

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.

THE perfect, hypothetical headlight is visualized, and a set of standards formulated that makes night driving as safe as day driving, with the illumination invisible to approaching cars. Theory of glare elimination with polarized light is presented. The nature of “Polaroid” and how it solves the problem is pointed out. The new engineering and lighting problems, which the use of this material involves, are discussed. Examples of the use of the new control of light for industry are related.

This paper describes some of the design solutions adopted in solving two major problems besetting man-powered aircraft in use: that of breakage and storage. It describes work leading up to the building and testing of “Phoenix”, a man-powered aircraft with a polyester-film inflatable wing. The paper deals mainly with aspects relating to the wing design and construction.

A sense of “personal integrity” blocks pilot use of new information about how he thinks. Research on human performance under stress done over the past fifty years indicates increased rigidity and regression to earlier learned behavior in high stress, and in low Stress a shift in attention to any domestic situation or on the job controversy which is of higher stress than that of the job at hand, all without the pilot's knowledge. Informal surveys of commercial pilot training and commercial pilot attitudes towards these studies indicate that the study findings directly confront learned cultural responses. Pilot and trainer reactions prevent the information from being adequately investigated or formally taught. The findings are not written into training manuals and pilots who are informally given the information do not have adequate access to the knowledge when it is needed.

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.

A multi vector design tool to accurately predict instrument panel obscuration was developed to insure that critical legal displays in vehicles are not obscured. The concept provides for a computer generated light source shaped to replicate the human eyes. The light source is then projected onto a 3D math based arrangement and the resultant shadows are visible on the instrument panel surface and its displays. Design studios require criteria for the placement of the instrument cluster gages and displays, various controls, switches, and steering column stalks before an interior theme can be completed. Therefore, instrument panel obscuration and visibility must be determined early in the design process. The obscured areas are a function of the instrument panel surface, steering wheel rim, hub, spokes, and the location of the driver's eyes. This light source method allows engineers and designers the ability to quickly determine obscured areas.

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.

“Melmoth,” an amateur-designed and built light airplane, has a number of features unusual in general aviation aircraft, aiming to combine comfort, high cruising speed, aerobatic capability and transoceanic range in a single compact machine. Among these are high wing loading, large internal fuel capacity, variable aileron incidence, double-slotted Fowler flap, automatic fuel tank switching, internal cowl flaps, and an all-flying T-tail.