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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.

ZF debuts ADAS deal and flexible inverter tech at CES 2022

Instantaneous combine grain yield monitors need to provide reliable yield measurements since yield as a function of location is key information needed to manage fields by management zones. A scale and a yield monitor measured the same stream of grain and provided similar results when compared to each other. Data from either device may be misinterpreted if care in calibration and operation is not taken. Careful operators who pay attention to calibration, maintenance, and manufacturer's instructions will be required.

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.

It is the goal of this paper, to discuss the impact of electronics on modern day commercial vehicles an buses. Seen from the position of advanced engineering of an European commercial vehicle manufacturer, the emphasis will be placed on the mechanical-electronical system itself, rather than the electronics themselves. User friendly, logic protected systems will minimize operator unfamiliarity and misapplication and will offer not only component control, but shortly the integration of all of these subsystems in the total vehicle control. Total vehicle control will be the ultimate result, when the driver, the truck and the environment are brought together. Such vehicles will be more responsive, safer and easier to drive than today's commercial vehicles and buses and offer a cost effective utilization of these new technologies to the customer.

The quality and availability of distillate fuels in the coming decades has become an increasing concern to the U.S. Navy. In response, the Energy Research and Development Office of the David Taylor Naval Ship Research and Development Center (DTNSRDC) has conducted a worldwide survey of commercial marine fuels. An effort was made to obtain 50 commercial marine fuel samples from various suppliers worldwide. The purpose of the survey was to assess the current quality of available fuels by analytically characterizing each of the fuel samples obtained. This assessment consisted of the measurement of more than 44 fuel properties. This paper contains a summary of the analytical results which were obtained. In addition, the current analytical results are compared with refinery specifications, with the current Navy specification, and with the results of a similar survey conducted in 1983. Finally, the resulting conclusions and recommendations are presented.

United States construction equipment manufacturers are subject to a maze of product-oriented regulations in marketing their U.S.-built products in foreign countries. These same obstacles face their foreign-built products. In the past, these foreign regulations were more apt to be trade barriers to protect domestic markets than bonafide regulations to protect the users. These trade barriers are gradually being lifted because manufacturers in virtually all countries have now expanded beyond their domestic markets. Thus, the same manufacturers that formerly encouraged trade barriers must now cope with them. This expansion of markets now encourages the elimination of trade barriers and the harmonization of regulations. For the future, regulations will be retained and expanded. They will, however, be harmonized with international voluntary standards rather than having different regulations for each country.

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.

Standardization and “Zero-Defects” are buzz-words among today's truck manufacturers. Electrical components is an area where these words must become reality. Components costing less than 1% of the final truck price should not cause problems for the end user or the manufacturer. The way to insure this is communication and design. Design out problems with new components.

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.

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.

A 1:10-scale wind tunnel development program was undertaken by the National Research Council of Canada and Airshield Inc. in 1994 to develop trailer side skirts that would reduce the aerodynamic drag of single and tandem trailers. Additionally, a second wind tunnel program was performed by the NRC to evaluate the fuel-saving performance of boat-tail panels when used in conjunction with the skirt-equipped single and tandem trailers. Side skirts on tandem, 8.2-m-long trailers (all model dimensions converted to full scale) were found to reduce the wind-averaged drag coefficient at 105 km/h (65 mi/h) by 0.0758. The front pair of skirts alone produced 75% of the total drag reduction from both sets of skirts and the rear pair alone produced 40% of that from both pairs. The sum of the drag reductions from front and rear skirts separately was 115% of that when both sets were fitted, suggesting an interaction between both.

A wind tunnel experiment has been conducted to determine the changes in drag and side force due to the presence and position of cab extenders on a model of a commercial tractor-trailer truck. The geometric variables investigated are the cab extenders angle of incidence, the tractor-trailer spacing and the yaw angle of the vehicle. Three cab extender angles were tested-0°, 15° (out) and -15° (in) with respect to the side of the tractor. The cab and trailer models have the same width and height. The minimum drag coefficient was found for the tractor and trailer combination when the cab extenders were set to 0° angle of incidence with respect to the headwind. This result holds for all yaw angles with moderate gap spacing between the tractor and trailer. This study suggests that commercial tractor-trailer trucks can benefit from adjustable cab extender settings; 0° when using a trailer and -15° when no trailer is used.

The use of devices to reduce aerodynamic drag on large trailers and save fuel in long-haul, over-the-road freight operations has spurred innovation and prompted some trucking fleets to use them in combinations to achieve even greater gains in fuel-efficiency. This paper examines aerodynamic performance and potential drag reduction benefits of using trailer aerodynamic components in combinations based upon wind tunnel test data. Representations of SmartWay-verified trailer aerodynamic components were tested on a one-eighth scale model of a class 8 sleeper tractor and a fifty three foot, van trailer model. The open-jet wind tunnel employed a rolling floor to reduce floor boundary layer interference. The drag impacts of aerodynamic packages are evaluated for both van and refrigerated trailers. Additionally, the interactions between individual aerodynamic devices is investigated.

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.

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.

New technology placed on specific components within the wheel end system, required modifications to existing tapered wheel bearing adjustment procedures. A new method for vehicles, which use tapered roller bearings, required a procedure addressing new technologies for the wheel end system. OEM and service technicians would benefit from concise procedures. Technologies engineered and developed for ABS (Anti-skid Brake Systems), extended brake blocks and synthetic lubricants, required research for the data base. Research to optimize the operating environment through improved maintenance procedures helped in achieving optimum wheel system operation. A tapered wheel bearing adjustment procedure and visual chart are the results profiting the vehicle manufacturers and field service technicians.

This paper discusses the relationship between users of construction equipment and the manufacturers and dealers of the equipment The people involved in this relationship are the deciding factors in whether all participants are satisfied, as the people are responsible ultimately for the product The paper points out that the major qualities necessary in the considerations behind a user's satisfaction with a manufacturer's product are those belonging to people, ingenuity, improvement, and integrity. Examples are shown from the user's point of view of the need for these qualities, of which integrity is the most important.