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Technical Paper

1500 Hp Diesel Electric Tractor

The experience accumulated with a prototype 1000 HP diesel electric tractor since 1969 is described. The new 1500 HP V220 diesel electric tractors are described along with some of the initial operation of these two units. Experience with the initial 1000 HP unit and the two 1500 HP tractors confirm the necessity of additional testing and experimentation to refine the design to get greater productivity with reduced operator fatigue. The unpredictability of the load and operating surface are major problems that present a real challenge to the engineer.
Technical Paper

50 Years of Agricultural Tractor Development

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.
Journal Article

6-Axis Measuring Wheels for Trucks or Heavy Vehicles

The measurement of the contact forces between road and tires is of fundamental importance while designing road vehicles. In this paper, the design and the employment of measuring wheels for trucks and heavy vehicles is presented. The measuring wheels have been optimized in order to obtain high stiffness and the approximately the same mass of the wheels normally employed. The proposed multicomponent measuring wheels are high- accuracy instruments for measuring the dynamic loads during handling and durability testing. The measuring wheels can replace the wheels of the truck under normal operation. Such family of wheels plays a major role in modern road vehicles development. The measuring wheel concept design is based on a patented three-spoke structure connected to the wheel rim. The spokes are instrumented by means of strain gauges and the measuring wheel is able to measure the three forces and the three moments acting at the interface between the tire and the road.
Technical Paper

A Basis for Estimating Mechanical Efficiency and Life of a Diesel Engine from its Size, Load Factor and Piston Speed

Parameters like brake mean effective pressure, mean velocity of the piston, hardness of the wear surface, oil film thickness, and surface areas of critical wear parts are similar for all the diesel engines. The mean piston velocity at the rated speed is nearly the same for all the diesel engines. The mechanical efficiency normalized to an arbitrary brake mean effective pressure (bmep) is dependent on the size of the engine. The engine life seems to be proportional directly to the square of a characteristic dimension namely, cylinder bore of the engine and inversely to speed and load factor for engines varying widely in sizes and ratings.
Technical Paper

A Bench Test for the Evaluation of Silver-Steel Lubrication Properties of Railroad Diesel Oils

A pin and disc machine has been modified for the evaluation of silver-steel lubrication characteristics of railroad diesel oils. Use of silver pins on polished steel discs at selected loads and rubbing speeds allows good correlation with known engine behavior. In comparison with wear and friction data obtained by the four ball method, this pin and disc test gives better correlation with engine tests than the Modified Four Ball Test.
Technical Paper

A Braking Force Distribution Strategy in Integrated Braking System Based on Wear Control and Hitch Force Control

A braking force distribution strategy in integrated braking system composed of the main braking system and the auxiliary braking system based on braking pad wear control and hitch force control under non-emergency braking condition is proposed based on the Electronically Controlled Braking System (EBS) to reduce the difference in braking pad wear between different axles and to decrease hitch force between tractors and trailers. The proposed strategy distributes the braking force based on the desired braking intensity, the degree of the braking pad wear and the limits of certain braking regulations to solve the coupling problems between braking safety, economical efficiency of braking and the comfort of drivers. Computer co-simulations of the proposed strategy are performed.
Technical Paper

A Cartridge Type Pivotal Pin and Bushing Joint

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.
Technical Paper

A Comparative Analysis of a Rigid Bicycle Model with an Elastic Bicycle Model for Small Trucks

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.
Technical Paper

A Comparative Study of Automotive System Fatigue Models Processed in the Time and Frequency Domain

The objective of this paper is to demonstrate that frequency domain methods for calculating structural response and fatigue damage can be more widely applicable than previously thought. This will be demonstrated by comparing results of time domain vs. frequency domain approaches for a series of fatigue/durability problems with increasing complexity. These problems involve both static and dynamic behavior. Also, both single input and multiple correlated inputs are considered. And most important of all, a variety of non-stationary loading types have been used. All of the example problems investigated are typically found in the automotive industry, with measured loads from the field or from the proving ground.
Technical Paper

A Comparison of Braking Performance of Asbestos, Non-Asbestos, and Semi-Metallic Friction Material

To date, no definitive work to quantify and compare the braking rating horsepower relationships between vehicles equipped with brake assemblies containing asbestos, non-asbestos, and semi-metallic friction material has been completed. This paper will report the results of a brake fade evaluation performed on a 34,000-lb. GVW vehicle in accordance with SAE J880 Brake System Rating Test Code Procedures and has quantified braking horsepower, fade temperature resistance, thermal response temperature rise, lining wear, and drum wear.
Technical Paper

A Comparison of Controller Designs for an Active, Electromagnetic, Offroad Vehicle Suspension System Traveling at High Speed

This paper discusses controller development for an active, off-road vehicle suspension system. A brief review of electronic filters and their characteristics is used to provide insight on the difficulties of designing a control algorithm for negotiating hilly and rough terrain at higher speeds. Two controller designs are presented. One was designed by pole placement and causes the suspension response to approximate a Type 1 Chebychev filter. The other was designed using constrained optimization. A comparison and discussion of simulation results leads to the conclusion that the suspension should be adaptively or predictively controlled for arbitrary terrain and velocity conditions.
Technical Paper

A Comparison of Fatigue Life Estimation on the Frequency Domain with Test Data and Time Domain Calculations

This paper focus on some of the fatigue methodologies based on the frequency domain and how they can be used on the heavy vehicle industry. A calculation flow was developed which consist of two steps. At first the stresses on the desired frequency bandwidth are calculated using a finite element software and those are then used as inputs on a Matlab script that estimate the expected life using two different theories, Bendat’s narrow band and Dirlik. The proposed methodology is then compared with more established time domain calculations. At first a plain hand calculation with a simpler input is performed on both domains before evaluating the differences with a more complex random stress signal input. Finally, test data from a rig test is used to validate the frequency domain fatigue methods using real life data.
Technical Paper

A Comparison of the Fatigue Lives of Polyvinylchloride & Steel Welds

This paper describes the results of a series of fatigue studies relating the lives of several weld geometries. Rotating beam and axially loaded specimens were used. A comparison between steel and plastic (polyvinylchloride scale models is made. Using plastic scale models of welded structures for fatigue life determination is the ultimate goal of this work.
Technical Paper

A Composite Approach to Reducing Abrasive Wear

“Today, wearing parts are regularly subjected to abnormal loading conditions. They must be able to accept these conditions without failure. In continuous operations, unscheduled downtime greatly increases maintenance costs, not to mention the cost of lost production. White iron castings offer premium abrasion resistance for many of these applications, but are often not used due to the possibility of brittle failure and the difficulty of mechanical attachment. This paper discusses the properties and applications of a composite of martensitic white iron and mild steel. This laminate will accept medium to high impact without loss of service failure, and can be installed by mechanical means or with welded attachment.”
Technical Paper

A Computer Program for Truck Frame Design

The classical methods of deflection analysis are finding more application to complex automotive chassis frame structures. Much too time consuming for manual application, they are now coming into more widespread use with the aid of high-speed computers. This paper describes a computerized deflection analysis for complete truck frames under the cases of torsion and flexure. The rapid, accurate analysis permits investigation of more design problems resulting in the eventual production of more efficient frame structures.
Technical Paper

A Contact Stress Model for Predicting Rolling Contact Fatigue

Predicting fatigue performance in concentrated contacts under thin film (or mixed) lubrication conditions has historically involved various empirical approaches. Typically a lubrication parameter is used in an experimentally derived equation to predict the expected rolling contact performance. However, this model doesn't explain the performance improvements. Enhanced finish bearings have exhibited longer life than standard finish bearings, especially when bearings are operated with thin EHL film. In this paper, the contact surfaces of test bearings were analyzed by using a micro-macro contact model in which the macro-contact was elastic contact, and the micro-contact was elastic-plastic contact. The interior subsurface stress maps were calculated from the real contact surfaces, which included the effects of roughnesses, waviness, and profiles.
Technical Paper

A Design Guide for Wet Multiple Plate Clutches on Forklift Truck Transmissions Considering Strength Balance between Friction Material and Mating Plate

Wet multiple plate clutches consist of friction plates, on which a friction material is bonded, and mating plates that are plain metal plates. Since the frequency and the range of load in the field of forklift trucks vary widely and are more severe than those for passenger cars, the wet multiple plate clutches on forklift trucks are often damaged. Damaged clutches that were returned from the field typically had 3 types of symptoms: 1.Only the friction material was damaged, 2.Only the mating plates were deformed, 3.Both symptoms were observed. It was clear that the cause of these symptoms depended on the difference of the operating application and the strength criteria of each part. This showed that a design guide for wet multiple plate clutches considering the strength balance between the two parts according to the work application was required. The relevant flow chart of this design process was proposed.
Technical Paper

A Detailed Analysis of Proper Safety Features Implementation in the Design and Construction of Modern Automotive LPG and CNG Containers

Paper describes analysis of the design process of modern automotive LPG and CNG containers. Over decade experience in the field of both computer based analysis as well as in the real conditions testing has been collected and presented in the paper. Authors present the potentials of modern FEM methodologies in the optimization and production of lightweight steel containers. It has been proved that the most sophisticated numerical analysis have to be followed by the construction verification, particularly considering direct exposure to fire. Bonfire test have become obligatory for both liquid and compressed gases containers. Properly chosen fire protection system, together with the adequate level of quality of materials applied for its production together with proper directing of the gas flowing out from safety devices are the essential factors defining gas containers fire safety.
Technical Paper

A Diesel Oxidation Catalyst for Exhaust Emissions Reduction

The authors used a mass spectrometer to determine an SOF reduction mechanism of a diesel oxidation catalyst. The results indicate that SOF reduction lies in the catalytic conversion of high molecular organic matter to low molecular organic matter. And unregulated emissions are also reduced through this conversion. It is also found that the SOF reduction performance is highly dependent up on the condition of the wash coat. There is some limitation to improving diesel oxidation catalyst performance because of the sulfur content found in diesel fuel. Finally, the authors have determined what we think are the specifications of the presently best catalytic converter.
Technical Paper

A Direct Method for Designing Fuel Filler Door with Torsional Spring

A direct method is developed for designing a vehicle fuel filler door with torsional spring. The design parameters include the door's geometrical parameters and spring dimensions. The design requirements are based on the finger force curve during closing and opening, and the bending stress in the spring. An example is included to demonstrate the effectiveness of the new method.