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Technical Paper

“SHIFT-MATE” A Fuel Efficiency Monitor

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.
Technical Paper

“MBE 4000-A New Engine for the US Class 8 Truck Market”

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.
Technical Paper

Yield Mapping with Digital Aerial Color Infrared (CIR) Images

Yield potential was predicted and mapped for three corn fields in Central Illinois, using digital aerial color infrared images. Three methods, namely statistical (regression) modeling, genetic algorithm optimization and artificial neural networks, were used for developing yield models. Two image resolutions of 3 and 6 m/pixel were used for modeling. All the models were trained using July 31 image and tested using images from July 2 and August 31, all from 1998. Among the three models, artificial neural networks gave best performance, with a prediction error less than 30%. The statistical model resulted in prediction errors in the range of 23 to 54%. The lower resolution images resulted in better prediction accuracy compared to resolutions higher than or equal to the yield resolution. Images after pollination resulted in better accuracy compared to images before pollination.
Technical Paper

Winnebago Front-Wheel Drive Motor Home Design and Assembly

The development of this vehicle is described from concept, through design and assembly. The design intent of this unique vehicle was high fuel efficiency, good ride and handling characteristics, and a high degree of passenger safety at a competitive cost. A combination of some of the latest in automotive and motor home construction technology was used to meet the desired goals.
Technical Paper

Wind-Averaged Drag Determination for Heavy-Duty Vehicles Using On-Road Constant-Speed Torque Tests

To investigate the feasibility of various test procedures to determine aerodynamic performance for the Phase 2 Greenhouse Gas (GHG) Regulations for Heavy-Duty Vehicles in the United States, the US Environmental Protection Agency commissioned, through Southwest Research Institute, constant-speed torque tests of several heavy-duty tractors matched to a conventional 53-foot dry-van trailer. Torque was measured at the transmission output shaft and, for most tests, also on each of the drive wheels. Air speed was measured onboard the vehicle, and wind conditions were measured using a weather station placed along the road side. Tests were performed on a rural road in Texas. Measuring wind-averaged drag from on-road tests has historically been a challenge. By collecting data in various wind conditions at multiple speeds over multiple days, a regression-based method was developed to estimate wind-averaged drag with a low precision error for multiple tractor-trailer combinations.
Technical Paper

Wind Tunnel Concepts for Testing Heavy Trucks

The trucking industry is being encouraged by environmental and cost factors to improve fuel efficiency. One factor that affects fuel efficiency is the aerodynamic design of the vehicles; that is, the vehicles with lower aerodynamic drag will get better mileage, reducing carbon emissions and reducing costs through lower fuel usage. A significant tool towards developing vehicles with lower drag is the wind tunnel. The automobile industry has made great improvements in fuel efficiency by using wind tunnels to determine the best designs to achieve lower drag. Those wind tunnels are not optimum for testing the larger, longer heavy trucks since the wind tunnels are smaller than needed. The estimated costs for a heavy truck wind tunnel based on automotive wind tunnel technology are quite high. A potential nozzle concept to reduce wind tunnel cost and several other new possible approaches to lower wind tunnel costs are presented.
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Wiley SAE MOBILUS® eBook Package

Committed to being the primary source for aerospace and ground vehicle engineering resources, SAE International has added the full compilation of our Wiley eBook collections to the SAE MOBILUS® technical resource platform. Purchasable as an annual subscription and containing the titles from the Wiley Aerospace Collection, the Wiley Automotive Collection, the Wiley Computer Systems Collection, and the Wiley Cyber Security Collection.
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Wiley Automotive Collection

Purchasable as an annual subscription, the Wiley Automotive Collection contains 20 eBook titles and focuses on a wide range of categories, including engines, transmission, chassis, body, electrical, safety, and manufacturing. Titles covering new and emerging topics such as battery technology and electric and hybrid vehicles are included as well, making the series an essential addition to any institution’s automotive resources.
Technical Paper

Why Not a New Engine ?

Leading contenders in the search for a superior alternative powerplant for light-duty automotive use include the steam and Stirling engines, the gas turbine, and the diesel. In this paper the status of each of those alternative engines is reviewed and i its prognosis considered. The steam engine is unsuitable because of poor fuel economy. Obstacles blocking acceptance of the Stirling and gas turbine engines are sufficient so that even if they are surmountable, significant-use in light-duty vehicles is unlikely before the 1990s. The light-duty diesel is here today but faces some difficult regulatory hurdles in the near future.
Technical Paper

Why Not 125 BMEP in an L-Head Truck Engine?

HIGH output per cubic inch of piston displacement is desirable not alone for the purpose of being able to transport more payload faster, but more particularly for the invariably associated byproduct of lower specific fuel consumption, and especially at road-load requirements. The only way of accomplishing this purpose is through the use of higher compression ratios, and the limiting factors for this objective are fuel distribution and the operating temperatures of the component parts. A manifold is proposed which not only definitely improves distribution at both full and road loads, but has the inherent additional advantage of reducing the formation of condensate, thus still further facilitating a reduction in road-load specific fuel consumption. Hydraulic valve lifters, obviation of mechanical and thermal distortion, and controlled water flow are the essentials in improved cooling.
Technical Paper

Whole Body Vibration Levels: A Realistic Baseline for Standards

Statistical measures of whole-body vibration from ambulation are shown to be higher than those from operation of earthmoving machinery and significantly higher than published guidelines for human exposure to whole-body vibration. The inconsistency of human response to low level vibration of technological origin as compared to human imperceptiveness to high level vibration from ambulation is discussed.
Journal Article

Wheel Chock Key Design Elements and Geometrical Profile for Truck Vehicle Restraint

Abstract Wheel chocks are rather simple compliant mechanisms for stabilizing vehicles at rest. However, chocks must be carefully designed given the complex interaction between the chock and the tire/suspension system. Despite their importance for safety, literature is surprisingly limited in terms of what makes a wheel chock efficient. Using simple but reliable quasi-static mechanical models, this study identifies mechanical requirements that help to avoid a number of failure modes associated with many existing wheel chocks. Given that chock grounding is not always possible, a chock’s maximum restraining capacity is only obtained when the wheel is completely supported by the chock. A generic chock profile is proposed to achieve this objective while mitigating undesirable failure modes. The profile is based on fundamental mechanical principles and no assumption is made on the load interaction between the chock and the wheel.
Technical Paper

What SPC Can Do for You

Quality improvement, widely accepted as the key to survival in today's global marketplace, can only be achieved through a disciplined approach to problem solving based on proven statistical process control (SPC) techniques. Improving quality also improves productivity, and SPC applications are generating substantial savings for both product and service organizations throughout industry.
Technical Paper

What Every Engineer Should Know About Finite Element Analysis Methods

The scope of Finite Element Analysis in the Product Development Cycle is given. A brief review of the development process is given. A brief description of the analysis method is presented. A description of how it works, how is it implemented, and where do I use it are included. The entire range of questions are answered through, how do I train for it, how do I manage it, along with what are the limitations and what are the benefits of this analysis method.
Technical Paper

Well-to Wheel Greenhouse Gas Emissions of LNG Used as a Fuel for Long Haul Trucks in a European Scenario

The EU Commission's “Clean Power for Transport” initiative aims to break the EU's dependence on imported oil whilst promoting the use of alternative fuels to reduce greenhouse gas emissions. Among the options considered is the use of liquefied natural gas (LNG) as a substitute for diesel in long haul trucks. It is interesting to ask how the lifecycle greenhouse gas (GHG) emissions of LNG compare with conventional diesel fuel for this application. The LNG available in Europe is mainly imported. This paper considers the “well-to-tank” emissions of LNG from various production routes, including: gas production, treatment and liquefaction, shipping to Europe, terminal, distribution and refuelling operations. “Tank-to-Wheel” emissions are considered for a range of currently-available engine technologies of varying efficiency relative to diesel.
Technical Paper

Weld Durability Analysis by Equilibrium-Equivalent Structural Stress Approach

Welding has been used extensively in automotive components design due to its flexibility to be applied in manufacturing, high structural strength and low cost. To improve fuel economy and reduce material cost, weight reduction by optimized structural design has been a high priority in auto industry. In the majority of heavy duty vehicle's chassis components design, the ability to predict the mechanical performance of welded joints is the key to success of structural optimization. FEA (finite element analysis) has been used in the industry to analyze welded parts. However, mesh sensitivity and material properties have been major issues due to geometry irregularity, metallurgical degradation of the base material, and inherent residual stress associated with welded joints. An approach, equilibrium-equivalent structural stress method, led by Battelle and through several joint industrial projects (JIP), has been developed.
Technical Paper

Weight Optimisation of Dumper Body Structure Conserving Stiffness, Buckling and Dent Performance

The entire commercial vehicle industry is moving towards weight reduction to leverage on the latest materials available to benefit in payload & fuel efficiency. General practice of weight reduction using high strength steel with reduced thickness in reference to Roark’s formula does not consider the stiffness & dent performance. While this helps to meet the targeted weight reduction keeping the stress levels within the acceptable limit, but with a penalty on stiffness & dent performance. The parameters of stiffener like thickness, section & pitching are very important while considering the Stiffness, bucking & dent performance of a dumper body. The Finite Element Model of subject dumper body has been studied in general particularly on impact of dent performance and is correlated with road load data to provide unique solution to the product. The impact of payload during loading of dumper is the major load case.
Training / Education

Weibull-Log Normal Analysis Workshop

RMS (Reliability-Maintainability-Safety-Supportability) engineering is emerging as the newest discipline in product development due to new credible, accurate, quantitative methods. Weibull Analysis is foremost among these new tools. New and advanced Weibull techniques are a significant improvement over the original Weibull approach. This workshop, originally developed by Dr. Bob Abernethy, presents special methods developed for these data problems, such as Weibayes, with actual case studies in addition to the latest techniques in SuperSMITH® Weibull for risk forecasts with renewal and optimal component replacement.
Technical Paper

Wear Generation in Hydraulic Pumps

This paper is concerned with the synergistic effects of pump wear modes. The objective is to investigate the wear produced by cavitation, adhesion, abrasion, and corrosion and to verify a proposed model of the synergistic pump wear process. The approach followed includes identification of the combined effects of different wear modes (synergisms) in a pump and the development of a synergistic wear model that includes pump operating and environmental conditions as trigger factors of wear modes. An experimental program was designed to evaluate the cavitation, adhesion, and corrosion wear effects in conjunction with the abrasive wear produced in a pump by measuring wear debris, particle size and gravimetric levels of fluid. The generation of wear was traced to different pump locations. The results obtained here suggest that improved pump design and longer pump service life can be obtained when synergisms between failure modes are properly understood.
Technical Paper

Ways to Meet Future Emission Regulations for Agricultural Tractor Engines

After a review of current and future emission legislation for non-road engines (India, Europe, USA), the various options available to reduce the emissions of diesel tractor engines are discussed. Special emphasis is put on naturally aspirated engines in the 37 - 50 kW power range. AVL has recently designed and developed several naturally aspirated heavy-duty diesel tractor engines to comply with current exhaust emissions standards for the Indian domestic and the US markets (EPA Tier 2). In doing so, different levels of technologies were applied. Their impact on mean effective pressure, specific fuel consumption and emissions will be shown. The future non-road engine exhaust emissions legislation in different markets will be addressed (India, Europe and USA). Compliance with the new emission standards will require the introduction of more advanced technology.