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This paper discusses individually and collectively the several factors which will affect future fuel trends in the farm tractor field. These factors are (1) past and present fuel consumption trends, (2) fuel manufacturing trends, (3) engine design and production trends, (4) economic trends. On the basis of this analysis it is concluded that the predominating farm tractor fuel of the immediate future will be regular grade gasoline, followed by LP-gas and diesel fuel. Future consumption of kerosine-type distillate will be insignificant. Gasoline tractors will continue to increase in compression ratio in order to take full advantage of the high octane number level of present gasoline. Gasoline tractors designed to burn premium grade fuel represent a trend in the more distant future.

Conventional materials like steel, brass, aluminum etc will fail without any indication, cracks initiation, propagation, will takes place with a short span. Now-a-days to overcome these problem, conventional materials are replaced by hybrid composite material. Not only have this conventional material failed to meet the requirement of high technology applications, like space applications and marine applications and structural applications in order to meet the above requirements new materials are being searched. Hybrid composites materials found to the best alternative with its unique capacity of designing the materials to give required properties and light weight. This paper aims to preparing hybrid composite using artificial fibers. Epoxy as resin and glass fiber as fiber for artificial hybrid composite to make a laminate for preparing leaf spring.

Fuel cells are a promising energy source on account of their high efficiency and low emissions. Proton exchange membrane fuel cells (PEMFC) are clean and environmental-friendly power sources, which can become future energy solutions especially for transport vehicles. They exhibit good energy efficiency and high power density per volume. Working at low temperatures (<90°C), hydrogen fuelled proton exchange membrane fuel cells (PEMFCs) are identified as promising alternatives for powering autos, houses and electronics. At the middle of the proton exchange membrane (PEM) fuel cell is the membrane electrode assembly (MEA). The MEA consists of a proton exchange membrane, catalyst layers, and gas diffusion layers (GDL). However, most of the researchers have already mentioned that PEMFC are not competitive enough to rechargeable lithium ion battery with respect to price because of the rare metal used such as platinum in it.

This paper details the investigation of the properties of inlet gases and shows how they affect the flow patterns immediately in front of the catalyst and the subsequent loss of efficiency. A thorough analysis of the flow distribution at the inlet of the catalyst enabled the effective catalyst diameter to be calculated. Subsequent calculations were then carried out to determine the loss of catalyst function through flow maldistribution. Experimental work involved flowing engine proportioned amounts of air through canisters of a fixed geometric profile containing a catalyst. Inlet cones of angles 10°, 15° and 45° were flowed to estimate the effect of the cone design on the velocity distributions at the face of the catalyst. Simple geometric profiles were investigated to allow a thorough understanding of the mechanism of flow to be comprehended and its affect on catalyst conversion to be analysed.

Mechanical handling of fruits from harvesting to marketing has often led to excessive bruises such that few of them make it to the fresh market. This has, therefore, called for a new engineering approach to determine the parameters which influence the firmness of fruits in order to reflect the optimum maturity for mechanical harvesting and post harvest handling. This paper reviews both the destructive and non-destructive techniques for determination of mechanical properties that influence the firmness of fruits. Mathematical equations relating fruit parameters like the Modulus of Elasticity, Poisson's ratio, bruise volumes, impact forces, energy absorbed by the fruit, fruit deformation and contact stresses are presented. Also, recent techniques used in mechanical handling of fruits to minimize bruises are addressed.

The cold starting and low temperature pumpability performance of twenty-one new and used multigrade oil formulations was determined in fired engine tests conducted with Caterpillar 3406B, Cummins NTC-365 and Detroit Diesel S-60 heavy duty engines. Viscosity grades included SAE 0W-30, 5W-40, 10W-30, 10W-40 and 15W-40, formulated with various commercial viscosity index improvers (VII's) including olefin copolymer (OCP), dispersant multifunctional olefin copolymer (MFOCP), polymethacrylate (PMA) and styrene-isoprene copolymer (SICP). Significant differences in pumpability characteristics were observed among the test engines, but there was no evidence of pumpability problems with the oils evaluated. In fact, significant pressurization of the oil delivery system occurred during engine cranking, prior to ignition. Good correlations were observed between the MRV test oil viscosities and pumpability characteristics in the test engines, both on an individual and on an average engine basis.

Truck driver's perception of ride quality/comfort is influenced by many factors relating to the driver, the vehicle and road surface roughness. A subjective rating survey was undertaken to identify the range of roughness wavelengths in the longitudinal road surface profile that affect the perceived ride of heavy articulated vehicles. They were found to range between 4.8 and 19.5 meters. Accordingly, a new roughness index called Profile Index (PI) was established. During the survey, data was collected on factors such as driver's age, years of driving experience, weight, vehicle's age, loading condition, cab location, type of driving axle suspension, weather condition and time of the rating. The effects of these factors were studied at different PI levels to test the viability of the PI as a measure of the perceived heavy vehicle ride and to establish if any of the above factors influenced the drivers' judgments during the survey.

This paper traces the evolution of heavy-duty truck transmissions in Europe, comments on the factors that have influenced and will influence the designs, compares some of the types in current use, and gives the author's views on possible lines of further development in the next decade. The ultimate predominance of any particular truck transmission will, of course, be the result of compromise between legislative, economic, and geographic factors. All these influences vary considerably in their effects on European truck manufacture as compared to that in the United States. The discussion of these differences points up areas of interest to manufacturers of transmissions who engage in export of their products.

This paper investigates the coefficients of static and kinetic friction between the hardwood flooring of a used van-type semi-trailer and the bottom surfaces of pallets fabricated from: high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), oak, or hickory. Tests to determine static and kinetic coefficients of friction (COF) were performed with the pallets moving longitudinally or transversely across the cargo trailer floor, and with varying loads. Using a general linear model to analyze the data collected, the best estimates of the COF (static, kinetic) for each pallet were found to be: HDPE (0.31, 0.20), LLDPE (0.29, 0.24), hickory (0.32, 0.21), oak (0.35, 0.25). The analysis also showed that pallet load had a small but statistically significant effect on the friction coefficients.

Man's use and control of energy is ever expanding and demanding new concepts and technology. One of the demands on construction equipment designers is that the operator be considered a “variable” component in the man/machine system. This paper deals with man's physical and psychological attributes along with machine characteristics that affect man and productivity. Guidelines are laid down for assignment of functions to the man versus the machine and design rules are spelled out. Some new technological concepts for earthmoving are also discussed.

With the development of autonomous driving technology, automated buses have begun trial operations in many cities around the world, and marketization has become an important issue. In order to explore the influencing factors of the public's willingness to use automated buses, two rounds of surveys were conducted. Firstly, the importance of the attributes of automated buses was studied, based on which questionnaires on willingness to use automated buses were designed. Using data from 266 questionnaires collected, a logistic regression model was established. Model results show that demographic variables and historical travel behavior characteristics will have a significant impact. Women are less willing to choose automated buses than men, and older people aged above 50 are more likely to use the mode. People who often use regular buses to travel have higher willingness to choose automated buses than people using other modes.

The incidence of pelvic and lower extremity fractures is examined by reference to data extracted from police and hospital records. It is shown that the incidence and number of fractures to the pelvis and the lower extremities is strongly dependent on the age of the struck pedestrian and the speed of the vehicle. Pelvic injuries are shown to be more common in elderly females than in other age groups and it is suggested that this is due to elderly females being more likely, with current vehicle front end heights, to sustain a direct blow at the level of the pelvis. Pubic rami fractures appear to result when there are distributed impact forces at the level of the pelvis and acetabular fractures occur when there are concentrated forces applied to the greater trochanter.

Investigations were carried out on five different soils at different moisture conditions. Soil resistance was measured with a hydraulic dynamograph on a single bottom plough operated with a tractor at 20-22 cm depth with a width of 60 cm. On light soils (sandy and loess soils) the soil resistance to ploughing was relatively small. The amplitude of instantaneous soil resistance measured from the mean value was also small. In the heavy loam soils, these variations were high. The highest instantaneous as well as the total soil resistance were found on the soil made of limy rock soil with a low organic matter. The magnitude of instantaneous soil resistance increased considerably with soil drying. The tillage tools must, therefore, overcome this short duration of high soil resistance. Such factors should be taken into consideration while designing new tillage tools.

ANALYSIS of engine cooling failures indicates the need for a special study of the automotive cooling system from the standpoint of design and construction, as well as of maintenance. Mr. Green carries out such a study here, discussing, in turn, the factors entering into each type of failure.

This work describes a statistic analysis of the service life of tires applied in off-highway trucks used in open-pit mining. Understanding the process of occurrence of structural failures, correlated to the fatigue mechanism and often observed in mechanic components, is of vital importance for the current industry. Since these failures usually happen suddenly, understanding them in the most diverse components submitted to cyclic loads helps analyzing the material’s progressive deterioration along time; it acts as a return to potential improvements in the product, giving feedback of computing simulation data; and it potentially increases operational safety by mitigating the consequences it has on the productive process and on the people exposed to such failures. The tires, components that integrate great part of the on wheels vehicles fleet - amongst them: transportation equipment, industrial mobile equipment and mining equipment - are inserted in this context.

Commercial vehicles have steering systems with one or more steering links connecting the steering gear box pitman arm and front axle steering arm. In case of twin steer vehicles, intermediate pivot arm is used to transfer the motion proportionately between the two front axles. Intermediate pivot arm is also used in some longer front over-hang vehicles to overcome their packaging constraints and to optimize the mechanical leverage. The pivot shaft is a mechanical part of the intermediate pivot arm assembly upon which pivot arm can swivel in one axis. Steering forces transferred through the drag links generates resultant forces and bending moments on the pivot shaft. In this work, study has been carried out on premature failure of the pivot shaft in city bus application model (Entry + 1 step). Metallurgical analysis of failed part indicated the failure to be due to fatigue. Pivot shaft was tested in rig with similar load conditions in order to replicate the failure.