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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.

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.

SIX BASIC suggestions are offered on how to design for practical, producible, economical structures of brazed honeycomb sandwich. The author illustrates the application of some of these design suggestions and explores the step-by-step theoretical reasoning a designer might use to arrive at a satisfactory design for a hypothetical large missile wing. The final design of a honeycomb sandwich component must take into account the process as well as structural and configuration requirements.

Data obtained when harvesting with a combine equipped with a yield monitor were used to develop yield maps. A prototype yield monitor was developed that uses a combination of light emitters and receivers mounted in a rectangular frame. The monitor was mounted in the combine in the top of the clean grain elevator. As grain flows through the monitor, a voltage change proportional to light reduction was recorded. This voltage was then correlated to grain flow rate. At the same time, site-specific location was recorded using the global positioning satellites (GPS) system. The location data, yield monitor output, cutting width, and combine forward speed were stored in a spreadsheet format. The data were then used to prepare the yield maps.

The idea of a world truck is a fascinating challenge - whereas cars are purchased more or less as seen; truck purchasers demand more individual configurations. In national and global terms, that means a highly complex truck market. Historically, a few European and North American manufacturers produced almost all the trucks for the world market. That changed through the 60's and 70's, with more local assembly plants around the world and increasing worldwide manufacturing capabilities. Concurrently, international component design standards have made some progress towards compatibility. Much greater co-operation is needed, however, before a genuinely international set of standards can be applied. As the task assigned to trucks is the same worldwide, namely to transport goods from A to B; it should be desirable and possible to work towards a greater commonality of vehicle - to ultimately achieve a world truck. The only unknown is the time scale.

In this study, we propose a method of measuring and analyzing the load on bolted joints used in a machine under off-road vehicle operation. Working load measurement under actual machine operation and the results of its analysis are shown as load frequency diagrams. An example of the measurement analysis of a load (three types of load: axial force, bending moment, and torsional torque) added to a bolted joint shank during actual machine operation is shown. In this paper, we describe how to apply the results of load analysis to the load condition at the design and experimental development stages.

Knitted wiremesh along with radial gas tight seals provide reliable mounting system for low temperature underbody converters. The compression characteristics of the wiremesh is modified by wire material, wire diameter, wire geometry, mesh crimp heights; wire density, wiremesh courses per inch, needle count, number of strands, wiremesh temper, wiremesh surface profile and surface characteristics. The radial mounting pressure provided by the wiremesh is matched with the mounting pressure requirement. Wiremesh systems can be tailored to any required radial mounting pressure from conventional to ultra thin-wall substrates. The wiremesh mounting system is proven durable, without any failure on more than 25 million underbody converters in light duty vehicles. Cp and Cpk show the capability of the manufacturing process. Thus the wiremesh mounting support is a viable alternate for low temperature gasoline and diesel applications.

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.

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.

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.

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.

Welding residual stress is one of the primary factors responsible for cracking at the access hole interface between the flange and web plate of welded heavy W-shapes. During multi-pass welding, cracks can be found in either the flange plate or the web plate, depending upon welding sequence, joint details and access hole size. In this study, an integrated numerical and experimental investigation was conducted to evaluate the effects of welding parameters and joint geometry on the magnitude and distribution of residual stresses in thick-section butt joints. The results provide guidelines for improved design for welding of heavy W-shapes.

An important emerging technical area is computer-based modeling of the various manufacturing processes that are used in many diverse industries. These models are used to optimize manufacturing techniques to reduce fabrication costs and improve the service performance. One manufacturing process important in steel fabrication is welding. It can be a useful tool to aid in reducing fabrication costs and service durability by optimizing the weld process and is the subject of this paper.

Abstract The use of appropriate loads and regulations is of great importance in weld fatigue assessment of rail on-track maintenance equipment and similar vehicles for optimized design. The regulations and available loads, however, are often generalized for several categories, which proves to be overly conservative for some specific categories of machines. EN (European Norm) and AAR (Association of American Railroads) regulations play a pivotal role in determining the applicable loads and acceptance criteria within this study. The availability of track-induced fatigue load data for the cumulative damage approach in track maintenance machines is often limited. Consequently, the FEA-based validation of rail track maintenance equipment often resorts to the infinite life approach rather than cumulative damage approach for track-induced travel loads, resulting in overly conservative designs.

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.

Weight reduction in construction equipment is sought to achieve energy conservation and also to comply with the vehicle safety and compliance regulations, managing the weight distribution across the rear and the front end of the equipment to achieve the optimum balancing. Of late the thrust on product weight has increased along with reduced time to market, leading to increased usage of structural optimization methods. This has been further supported by the availability of high performance computing at relatively low cost. VOC and CTQ tools provided the motivation and initial screening of the design variables. The structural optimization software provides an integrated platform for analysis as well as optimization of components. In this work, an optimization tool has been used for size and shape optimization of a construction equipment assembly and a commercial FEA package was used for verification and validation of the results.

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.

A significant driver for the development of future commercial vehicles is likely to be the introduction of fuel consumption related legislation in various regions around the world. The application of a waste heat recovery system to the powertrain of such vehicles is seen as a possible step, amongst many, to help them achieve the required fuel economy. In particular, the Rankine Cycle (a closed steam cycle) is often proposed as a potential means for deriving work from the engine exhaust heat. Rankine Cycle systems are already in use in off-highway applications, such as stationary engines or marine power-packs. However, the technical and commercial viability of these systems for on-highway, principally long haul truck application is as yet unproven. Aspects such as the in-use economy benefits, the system performance density, the component robustness and all interactions with the other vehicle systems have to be evaluated.

Nearly a third of the fuel energy is wasted through the exhaust of a vehicle. An efficient waste heat recovery process will undoubtedly lead to improved fuel efficiency and reduced greenhouse gas (GHG) emissions. Currently, there are multiple waste heat recovery technologies that are being investigated in the auto industry. One innovative waste heat recovery approach uses Thermoacoustic Converter (TAC) technology. Thermoacoustics is the field of physics related to the interaction of acoustic waves (sonic power) with heat flows. As in a heat engine, the TAC produces electric power where a temperature differential exists, which can be generated with engine exhaust (hot side) and coolant (cold side). Essentially, the TAC converts exhaust waste heat into electricity in two steps: 1) the exhaust waste heat is converted to acoustic energy (mechanical) and 2) the acoustic energy is converted to electrical energy.

The use of reciprocating internal combustion engines (ICE) dominates the sector of the in-the-road transportation sector, both for light and heavy duties. CO2 reduction is the technological driver, considering the severe worldwide greenhouse commitments. In ICE more than one third of the fuel energy used is rejected to the environment as thermal waste through the exhaust gases. Therefore, a greater fuel economy could be achieved, recovering this energy and converting it into useful electric power on board. Financial benefits will be produced in terms of fuel cost which will rebound similar benefits in terms of CO2 emitted. For long hauling vehicles, which run for thousands of miles, frequently at fixed engine operating conditions, this recovery appears very worthy of attention. In this activity, an ORC-based power unit was designed, built and tested fed by a heavy duty diesel engine, so contributing to the huge efforts on going in that specific sector.