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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 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.

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.

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.

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.

There are many different vibration sources in a car. Engine, gears, road roughness, impacts against the wheels cause vibration and sound that can decrease the parts and the car durability as well as affect drivability, safety and passengers and community comfort. In 4×4 cars, some extra vibration sources are the parts responsible for transmitting the torque and power to the rear wheels. Each of them has their own vibration modes, excited mostly by its imbalance or by the second order engine vibration. The engine vibration is a very well known phenomena and the rear driveshaft is designed not to have any vibration mode in the range of frequencies that the engine works or its second order. The imbalance of a driveshaft is also a design requirement. That means, the acceptable imbalance of the driveshaft is limited to a maximum value.

The “Rigidization-on-Command”™ (ROC™) resin development has focused on the development of resin systems that use UV light cure for rigidization. Polymeric sensitizers have been incorporated into the resin formulations to promote cure using Pen-Ray lamps and UV light-emitting diodes (LED's). Formulations containing the polymeric sensitizers were examined by FTIR and DSC. Complete cure was observed after 15 min. exposure with the Pen-Ray lamps. Performance of the Pen-Ray lamps and UV LEDs was thoroughly characterized. Thermal models were developed to optimize the performance of the of the MLI insulation thermal oven used for orbital cure of the boom. Results show that -12°C is the lowest temperature required for cure of the ROC™ resin systems.

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.

This paper describes the engine design details of the Pratt & Whitney JT15D-1 engine as related to noise generation. Design principles and factors contributing to the very low-noise levels on the Cessna Citation aircraft are illustrated. Noise testing experiences and data from static tests on the United Aircraft of Canada Ltd. (UACL) flight test aircraft and from both static and flight tests on the Citation aircraft are discussed. Lessons learned from these tests and some future probabilities are outlined.

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.

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.