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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.

Powertrain electrification is becoming increasingly common in the transportation sector to address the challenges of global warming and deteriorating air quality. This paper introduces a novel “Build Your Hybrid” approach to experience and test various hybrid powertrain concepts. This approach is applied to the light commercial vehicles (LCV) segment due to the attractive combination of a Diesel engine and a partly electrified powertrain. For this purpose, a demonstrator vehicle has been set up with a flexible P02 hybrid topology and a prototype Hybrid Control Unit (HCU). Based on user input, the HCU software modifies the control functions and simulation models to emulate different sub-topologies and levels of hybridization in the demonstrator vehicle. Three powertrain concepts are considered for LCVs: HV P2, 48V P2 and 48V P0 hybrid. Dedicated hybrid control strategies are developed to take full advantage of the synergies of the electrical system and reduce CO2 and NOx emissions.

GREATER ease of servicing is one of the ultimate goals in the development of dry-type air cleaners. The authors acknowledge, however, that the oil-bath cleaner is a rugged proved component that has done a good job for the farmers who serviced it properly. This paper describes studies made in Illinois of oil-bath and dry air cleaners in field service. At the same fuel/air ratios, the maximum horsepower of a test engine was greater with the dry-type filter than with the oil-bath cleaner. It was found that with AC fine dust and steady airflow, the oil-bath cleaners had significantly lower efficiencies than the dry-type filter. At less than rated airflow the efficiency of the oil-bath cleaner decreased while that of the dry filter remained high.

ZF uses innovative motor cooling, winding technology and its transmission heritage to produce a more efficient and powerful drivetrain for electric vehicles.

This paper describes the ZF - Intarder, a wear-free vehicle brake for commercial vehicles. Qualities such as optimum weight saving, compactness, compatibility with all PTOs and no change in driveshaft length, are the results of a new development. Performance measurements demonstrate connection with engine cooling system. Field test measurements provide new information about frequency of use of various brake levels and electronic speed control. An evaluation of financial issues indicates advantages for operation.

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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.

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.

Tractor semi-trailer stability during emergency braking and steering maneuvers has been an issue that was improved through implementation of Anti-lock Braking Systems (ABS). Although some improvements have been achieved, the need for new control methodologies is evident from the number of accidents reported by NHTSA involving tractor semi-trailers. In this paper, a new control algorithm has been developed for improving the tractor semi-trailer stability through utilization of yaw moment, i.e., tire differential braking strategy. This new, multifaceted, adaptive control algorithm which allows the estimation of the unknown vehicle parameters through use of the adaptation laws is based on the Lyapunov Direct Method. A tractor semi-trailer model with four degrees of freedom was used to develop the control algorithm and the adaptation laws. The controller was implemented on a 2-axle tractor 1-axle van trailer in TruckSim 7©.

This paper investigates the yaw dynamic behaviour of a seven axle tractor semitrailer combination vehicle developed by VRDE (Vehicle Research & Development). The semitrailer has four steerable axles which follow command steering law i.e. all axles of semitrailer are steered in a particular relation with articulation of tractor. A 4 dof (degree of freedom) linear yaw plane model was developed for this combination vehicle. Yaw response characteristics such as lateral acceleration, yaw rate and articulation angle for step and sine steer is obtained from this model. Effects of speed on the above parameters are also studied to the same steering inputs. Lateral tyre forces due to semitrailer steering at various speeds are estimated to understand its distribution on each axle. Steady state yaw rate and articulation angle gain are obtained to predict the understeer / oversteer behaviour of combination vehicle.

All around the world, steps are being taken to improve the quality of our environment. Prominent among these are the definition, implementation, and attainment of increasingly stringent emissions regulations for all types of engines, including off-highway diesels. These rigorous regulations have driven use of technologies like after-treatment, advanced air systems, and advanced fuel systems. Fuel dispensed off-highway is routinely and significantly dirtier than fuel from on-highway outlets. Furthermore, fuels used in developing countries can be up to 30 times dirtier than the average fuels in North America. Poor fuel cleanliness, coupled with the higher pressures and performance demands of modern fuel systems, create life challenges greater than encountered with cleaner fuels. This can result in costly disruption of operations, loss of productivity, and customer dissatisfaction in the off-highway market.

With COSMOsim, OTSL is looking to better virtually recreate diverse driving conditions to enable safe and accurate verifications at a point when autonomous driving continues to move toward practical use around the world.

The published SAE J2954 standard established an industry-wide specification that defines acceptable criteria for interoperability, electromagnetic compatibility, EMF, minimum performance, safety, and testing for wireless power transfer (WPT) for light-duty plug-in electric vehicles. This SAE Information Report, SAE J2954/2, defines new power transfer levels in the higher power ranges needed for heavy-duty electric vehicles. This document addresses the requirements based on these charge levels and different vehicle applications as a first step in the process of completing a standard that the industry can use, both for private (fleet) and public wireless power transfer, including for charging electric vehicle batteries. This document is the first step in a process towards HD static and dynamic WPT. This document lacks specific requirements and solutions, for which field data is needed.

This report is concerned with the effects of braid angle on the behavior of hydraulic hose. For equilibrium conditions to exist, and if the braid layers are assumed to bear tension forces only, the angle of the reinforcement layers must be along that of the total force exerted by the internal pressure. This is the neutral angle θN, which has a theoretical value of 54.74° (54°44′). It is possible to hypothesize a fretting wear model in which wires move on top of one another inside a braid layer if the braid angle is different from this theoretical neutral angle. Even though theoretical claims are made by some technical professionals, the hydraulic hose industry has been successfully making hoses with non-neutral braid angles for years. Testing and application have shown that fretting wear is not a principal cause of hose failure and fatigue.

This SAE Recommended Practice establishes uniform test procedures and performance requirements for the defrosting system of enclosed cab trucks, buses, and multipurpose vehicles. It is limited to a test that can be conducted on uniform test equipment in commercially available laboratory facilities. Current engineering practice prescribes that for laboratory evaluation of defroster systems, an ice coating of known thickness be applied to the windshield and left- and right-hand side windows to provide more uniform and repeatable test results, even though under actual conditions such a coating would necessarily be scraped off before driving. The test condition, therefore, represents a more severe condition than the actual condition, where the defroster system must merely be capable of maintaining a cleared viewing area.

The effect of eight installation and component parameters on cooling system heat rejection and air flow were examined in detail in a wind tunnel facility. A quarter-replicate, two level factorial test plan was followed. Within the ranges of each parameter tested, the fan characteristics and the projection of fan into the shroud are highly significant parameters. The fan to radiator distance, the radiator characteristics, and the fan tip to shroud clearance are significant parameters. The fan to engine block distance and the type of shroud are not significant parameters.

Through this work, Wind River and Airbiquity look to enable secure and intelligent software updates and data management for these vehicles through over-the-air (OTA) programming technology. The work may also lead to similar solutions for traditional aerospace and unmanned aircraft system (UAS) industries.

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.

Cast iron is generally thought of as a weak, dirty, cheap, brittle material that does not have a place in applications requiring high strength and defined engineering properties. While gray cast iron is relatively brittle by comparison with steel, ductile iron is not. In fact, ductile iron has strengths and toughness very similar to steel and the machinability advantages make an attractive opportunity for significant cost reductions. Gray and ductile iron bar stock is commercially available and can be used as a direct replacement in applications that are currently being made from carbon steel bar. Ductile iron bar stock conversions are very prevalent in many fluid power applications including glands and rod guides, cylinders, hydrostatic transmission barrels and in high-pressure manifolds. Automotive gears are being converted to ductile iron for its damping capacity and cost reductions.

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.