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The story of Power Farming is the great saga of our times. It is a story of free enterprise, perseverance and endurance of the individual, of vision, idealism and cooperation among men, of the lightening of human toil and the release of millions of workers from farms to feed the ever hungry industrial revolution. By no means least, it is the story of producing food necessary to win two global wars, keep our allies alive and millions of the defeated enemy from starvation. FOREWARD By 1915, the Steam Traction Engine had attained its highest development. It was the forerunner, rather than the predecessor, of the farm tractor. The former was the instrument of expansion; the latter, the instrument of progress. The invention of the tractor, following by only sixteen years Otto's practical embodiment application of the Beau de Rochas power cycle to a heat engine, marked the advent of a new order - - the age of Power Farming.

The model 753 skid steer loader was developed to address performance, service and manufacturing issues for the company's 1300 lb. class loader and to provide exciting new features for marketing. This paper describes many of the improvements and features that will accentuate the Bobcat skid steer loader family in the nineties.

The 9000T track-type agricultural tractors mark John Deere's entry into the high-horsepower, track tractor market. The 360-HP 9300T and the 425-HP 9400T tractors were designed with input from customers to meet customers' needs. Through customer input, on-farm research, and common sense, these tractors have been designed to work light in the spring, heavy in the fall, handle steep hillsides, turn under load and pull like a locomotive. Incorporating many of the already-market-dominating features of the 9000 wheel tractors plus innovative track vehicle features such as the wide stance, long wheel base, controllability, power, and versatility, these machines are truly amazing.

Recently designed and fabricated in Kennewick, Washington, a pair of 2000 ton capacity crawler/transporters has been used in moving refinery modules to permanent installations on Alaska's North Slope. Vehicle design features include four corner chain-driven, track driving sprockets (tumblers), resilient track roller suspensions, elevating load platform (hereinafter “bolsters”), dynamic braking, diesel/torque converter power, automatic lubrication and electro-pneumatic controls. Four independent power units provide 14 00 horse-power per crawler and over two million pounds of drawbar pull at converter stall. Weighing 300 tons, the pin-connected crawler dissembles for highway transport into loads of under 95,000 pounds.

The paper investigates the interaction between soil and tractor tires through a 2D numerical model. The tire is schematized as a rigid ring presenting a series of rigid tread bars on the external circumference. The outer profile of the tire is divided into a series of elements, each one able to exchange a normal and a tangential contact force with the ground. A 2D soil model was developed to compute the forces at the ground-tire interface: the normal force is determined on the basis of the compression of the soil generated by the sinking of the tire. The soil is modeled through a layer of springs characterized by two different stiffness for the loading (lower stiffness) and unloading (higher stiffness) condition. This scheme allows to introduce a memory effect on the soil which results stiffer and keeps a residual sinking after the passage of the tire. The normal contact force determines the maximum value of tangential force provided before the soil fails.

The paper discusses the fact that in a year when economic conditions might be saying “don't buy”, there may be good business reasons to buy trucks. It is based on a study made with the cooperation of a truck operator who permitted the analysis of all aspects of his operation. After the study, the operator did buy trucks in a year when, on the surface, it appeared new truck purchases wouldn't be justified because of economic conditions. The operator also changed his buying pattern from his past practice of glider kitting trucks for replacement and buying new trucks only for expansion.

A cartridge type pivotal pin and bushing joint has been patented and is being tested and refined both in the laboratory and on construction machinery. It features “dry lubricated” (Teflon) bearings which are assembled and sealed prior to installation. It is suitable for heavy unit loads and use under severe wear conditions, such as in crawler track chains and loader bucket pivotal pin joints. A brief history of U. S. manufactured track pin joints is included to show the progress in extending the service life of these devices.

This paper describes the application of statistical techniques related to the condensation of computational models so that gradient based optimization procedures can be used more effectively. The adoption of these techniques is encouraged by the possibility of an important reduction in time and cost associated to the vehicle development process. A sophisticated computational model of a Mini-baja vehicle is defined in the virtual environment by means of CAD/CAE software, intending to provide the major information related to the study of its dynamic behaviour and to define the statistical surrogates (approximate models). The creation of the computational model deals with the determination of physical and geometric properties, and is fed by stiffness and damping parameters obtained through experimental procedures.

Indian automobile production increased at a CAGR of 12.2% over FY05-FY13, with a decline in Commercial Vehicle (CV) growth rate during FY09 and FY13. Globally, automotive industry suffered a decline in FY09 due to the global financial crisis and again on a decline in FY12 due to the European sovereign debt crisis. Apart from the global events, there are various internal risks the Indian OEMs need to consider: 1) regulatory risk due to excise duty hikes, decontrol of fuel pricing, etc., 2) market risks due to currency, inflation, interest rates, material cost, 3) industry risks due to increased competition, price war, etc. In this scenario, Indian Original Equipment Manufacturers (OEMs) need to constantly recalibrate their strategies to the changing market dynamics and associated risks. A research on megatrends affecting the Indian CV industry has identified more focus on Total Cost of Ownership (TCO) as one of the megatrend.

This paper starts with an analysis of design configurations of the drivelines with different power-dividing units (PDUs) of main dump truck manufacturing companies. As it follows from the analysis, improvements of articulated truck energy efficiency and reduction of fuel consumption by optimizing the power distribution to the drive wheels are still open issues. The problem is that a variety of operating and terrain conditions of dump trucks requires different wheel power distributions that cannot be provided by one set of PDUs employed in a truck. The central PDU in the transfer case was identified as the most important PDU among the five PDUs, which plays a crucial role in the power distribution between the front axle and the rear tandem of a 6×6 articulated dump truck. The paper formulates a constraint optimization problem to minimize the tire slippage power losses by optimizing the power distribution between the drive wheels.

Current trends in application technology indicate an increasing realization on the part of manufacturers and users of agricultural chemicals of the important role that application techniques and/or equipment play in the overall success of pesticide application. The trends that are most significantly influencing the way chemicals are currently applied include: increased emphasis on improving the accuracy of application increased use of low volume application (3-8 GPA) renewed interest in use of granular application increased use of conservation tillage increased emphasis on reduction in environmental contamination, both within and outside the target area increased use of highly active cam-pounds

The use of virtual prototyping early in the design stage of a product has gained popularity due to reduced cost and time to market. The state of the art in vehicle simulation has reached a level where full vehicles are analyzed through simulation but major difficulties continue to be present in interfacing the vehicle model with accurate powertrain models and in developing adequate formulations for the contact between tire and terrain (specifically, scenarios such as tire sliding on ice and rolling on sand or other very deformable surfaces). The proposed work focuses on developing a ground vehicle simulation capability by combining several third party packages for vehicle simulation, tire simulation, and powertrain simulation. The long-term goal of this project consists in promoting the Digital Car idea through the development of a reliable and robust simulation capability that will enhance the understanding and control of off-road vehicle performance.

The paper addresses some aspects of an ongoing research on a commercial compact excavator. The interest is focused on the analysis and modelling of the whole hydraulic circuit that, beside a load sensing variable displacement pump, features a stack of nine proportional directional control valves modules of which seven are of the load sensing type. Loads being sensed are the boom swing, boom, stick and bucket, right and left track motors and work tools; instead, the blade and the turret swing users do not contribute to the load sensing signal. Of specific interest are the peculiarities that were observed in the stack. In fact, to develop an accurate AMESim modelling, the stack was dismantled and all modules analysed and represented in a CAD environment as 3D parts. The load sensing flow generation unit was replaced on the vehicle by another one whose analysis and modelling have been developed using available design and experimental data.

In the truck industry there is a continuous demand to increase the efficiency and to decrease the emissions. To acknowledge both these issues a waste heat recovery system (WHR) is combined with a partially premixed combustion (PPC) engine to deliver an efficient engine system. Over the past decades numerous attempts to increase the thermal efficiency of the diesel engine has been made. One such attempt is the PPC concept that has demonstrated potential for substantially increased thermal efficiency combined with much reduced emission levels. So far most work on increasing engine efficiency has been focused on improving the thermal efficiency of the engine while WHR, which has an excellent potential for another 1-5 % fuel consumption reduction, has not been researched that much yet. In this paper a WHR system using a Rankine cycle has been developed in a modeling environment using IPSEpro.

The planar rigid bicycle model is one of the most popular models used in vehicle dynamics. It has widely been used in studying vehicle handling characteristics and designing steering control system for vehicles. This paper analyses a modified dynamic model called the "Elastic Bicycle Model." This model improves upon the classical bicycle model by taking into account the flexibility of the vehicle frame by using concepts from the Euler beam theory. Complete set of the resulting dynamic equations of this model are presented. Non-dimensional versions of the equations are used to investigate the steady state response of the model. Finally, the results of the response study obtained by modeling a small truck with an elastic model and the classical bicycle model are presented. These include the steady state solutions as function of different parameters as well as a transient solution in response to a saw-tooth steering input and a step input. Octave® has been used for simulation purpose.

The Standard Multipass (Beta) Filter Method (ISO 4572) has been a highly recognized and widely accepted test throughout industry since its introduction in the early 1970's. In the past decade, the Beta Method has indeed made a major contribution in assisting users in selecting filters to meet system design requirements. However, many complaints have been voiced by users that filters normally produce a lower particle removal efficiency under field applications than they do during laboratory tests. Research results from work carried out at the Fluid Power Research Center at Oklahoma State University indicate that the degradation of the filtration (Beta) ratio in service depends mainly on the filter's retentivity characteristic. This paper highlights the theoretical basis of the Epsilon Rating Method and the concept of retentivity. Most important, the paper uses these concepts to correlate filter performance between laboratory tests and field operation.

Engine mounts are an integral part of the vehicle that helps in reducing the vibrations generated from the engine. Engine mounts require a simple yet complicated amalgamation of two very different materials, steel and rubber. Proper adhesion between the two is required to prevent any part failure. Therefore, it becomes important that a comprehensive study is done to understand the mating phenomenon of both. A good linking between rubber and metal substrate is governed by surface pretreatment. Various methodologies such as mechanical and chemical are adopted for the same. This paper aims to present a comparative study as to which surface pretreatment has an edge over other techniques in terms of separation force required to break the bonding between the two parts. The study also presents a cost comparison between the techniques so that the best possible technique can be put to use in the commercial vehicle industry.

In recent years due to significant increased cost of raw material, fuel and energy, vehicle cost is increased. As vehicle cost is one of the major factors that attracts prospective buyers, it has created specific demand for low weight and low-cost components than traditional components with better performance to meet customer expectations. Suspension is one of the critical aggregates where lot of material is used and reduction in weight tends to give lot of cost benefit. As suspension system derives vehicle’s handling performance, it has to be ensured that handling performance of vehicle is maintained the same or made better while reducing weight of the suspension. Advancements in simulation capabilities coupled with manufacturing technology has enabled development non-traditional leaf springs. One of such springs is mono-leaf spring without shackle. This type of leaf spring provides advantages such as low weight and nonlinear stiffness.

Despite the general similarity of U.S. and European heavy trucks, there are differences in design properties that affect braking and turning performance. A European tractor-semitrailer was studied for the purpose of comparing its properties to those of U.S. vehicles and assessing the comparative performance. Mass, suspension, and braking system properties of the European tractor and semitrailer were measured in the laboratory and on the proving ground. Turning and braking performance qualities were evaluated by computer simulation and by experimental tests. In turning performance the European combination had a 9 percent advantage in rollover threshold, compared to a generic U.S. vehicle with properties that were in the midrange of U.S. design practice. Higher suspension roll stiffness and higher chassis weight on the European tractor and semitrailer accounted for the higher threshold.

This paper presents the analytical results of two different computer simulations of the vehicle pedestrian impact; PROMETHEUS 2 and the MacLaughlin/Daniel (MACDAN) models. The results presented illustrate the simularity and differences between the two models and accuracy of both to predict the actual occurrance. Also presented is a discussion relative to the modeling techniques of obtaining data for the pedestrian. This presentation illustrates the scaling techniques and actual data obtained in order to accurately simulate the pedestrian.