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Advanced Vehicle Technologies (AVT), a Ballarat Australia based company, has developed the World's first diesel to 100% LPG conversion for heavy haul trucks. There is no diesel required or utilized on the trucks. The engine is converted with minimal changes into a spark ignition engine with equivalent power and torque of the diesel. The patented technology is now deployed in 2 Mercedes Actros trucks. The power output in engine dynamometer testing exceeds that of the diesel (in excess of 370 kW power and 2700 Nm torque). In on-road application the power curve is matched to the diesel specifications to avoid potential downstream power-train stress. Testing at the Department of Transport Energy & Infrastructure, Regency Park, SA have shown the Euro 3 truck converted to LPG is between Euro 4 and Euro 5 NOx levels, CO2 levels 10% better than diesel on DT80 test and about even with diesel on CUEDC tests.

Two new 4 X 4 drivetrain systems have been developed for highway tractors that are used to pull multiple trailer combinations. The first one is a 4 X 2 that automatically becomes a 4 X 4 when conditions exist that require 4 X 4 operation. The second one is a full-time 4 X 4 that proportions the drive torque 36% to the front axle and 64% to the rear axle. A unique front driving steering axle has also been developed that permits a 4 X 4 system to be installed in a standard 4 X 2 truck. There is no need to relocate any major components to make space available for a front driving steering axle.

J I Case Company has produced four-wheel-drive agricultural tractors since 1964. In 1984 however, the flagship of the Case fleet changed hands. Rising labor costs and larger farming operations spearheaded the need for a more efficient larger tractor. January 1984 marked the introduction of the largest four-wheel-drive tractor in the history of Case, the 4994, a 400-gross engine horsepower tractor, Figure 1. Sheer horsepower alone however, would not meet the requirements of today's farming operations. Case Engineering realized that tomorrows tractors must have sufficient power to handle the wide variety of attachments available. They also realized that along with the unmatched power must come precise control of the attachment. These advancements in farming have required improvements to the tractor hydraulic system. This paper describes the hydraulic system of the 4994, Case's new flagship.

Over the past several years the Institute of Electrical and Electronic Engineers (IEEE) Standards Association has developed standards for the 5.9 GHz Dedicated Short Range Communications protocols, also known as Wireless Access in Vehicular Environments. These standards consist of IEEE 1609 as well as an amendment to the IEEE 802.11 standard or 802.11p. The 1609 standards were published for Trial Use and these as well as the 802.11p draft have been implemented in a variety of test beds to provide lessons learned and feedback into the standards working groups. Based on ongoing testing, the protocols display a strong capability to address the requirements of crash avoidance and transportation mobility applications. The corresponding test results provide information necessary to update the standards after the first trial phase as industry moves toward commercial implementations.

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.

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.

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.

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.

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.

“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.”

A Decision Network is an explicit model of the Thinking Breakdown Structure of any complex scientific, engineering, or societal challenge. Each node in the Decision Network represents a fundamental question that must be answered, i.e. a choice that demands a solution. A Decision Network provides an integrated Decision Management framework for any Systems Engineering effort that links business, technology and design choices. Effective Decision Management is the key to Systems Engineering success. This paper will provide an overview of a decision-centric approach to Systems Engineering built around Decision Networks. Lessons learned through the use of Decision Networks in other industries will be extrapolated for use in vehicle Systems Engineering.

A new hydro-mechanical coupling has been developed for use as a slip limiting device in differentials, axle and transfer cases as well as a stand alone, self contained transmission coupling for all wheel drive applications. The exceptional torque capacity to packaging size ratio of this device allows secondary axles to be driven exclusively through the coupling before or after the final drive reduction. In this paper, the operation principle and general construction of the Gerodisc type coupling devices are discussed as well as analysis and comparison of theoretical performance capabilities, laboratory bench test data and actual on vehicle field testing data.

Heavy commercial vehicle axle shafts are designed for torsion load. Typically, axle shaft fracture mode during the test is torsional in nature through either shaft body diameter or spline end. However, some of the field return axles shows fracture mode on axle shaft flange. This fracture mode does not resemble with a typical lab test torsional fracture. Metallurgical investigation report indicated that the fracture mode is bending in nature. This paper thus focuses on detail study of change in boundary condition and load transfer path under abusive vertical bending load on axle. A detail finite element analysis is performed to understand stress state change in axle shaft under this condition. A fracture hypothesis is proposed based on observations of finite element analysis results. A detail case study is presented depicting correlation of proposed hypothesis with physical fracture mode.

Adjuster rings are used in commercial vehicle axle assembly to preload differential bearings and provide support in the axial direction. Adjuster along with the carrier and bearing cap combined to form a threaded joint. Adjuster with external threads engages with internal threads formed in carrier and bearing cap. Preload in differential assembly maintains the system rigidity and helps to maintain an optimized hypoid gear engagement. An adequate preload is important to achieve a desirable bearing life. Reduction in thread engagement at adjuster joint fully or partially will cause a reduction in preload and can lead to gear misalignment. This can cause severe durability concerns. In some cases, it is observed that under vehicle operating loads adjuster ring is backed off from its assembled condition by bending the split pin (split pin is, positive lock, used to maintain adjuster position) and adjuster threads were stripped off.

The simulation of the longitudinal performance of trucks and articulated vehicles requires careful attention to tandem axle dynamics, the brake system model, and the tire model. The approach which was taken to these problems in a recently developed digital simulation is given. Results for the braking performance of an articulated vehicle and a straight truck are compared to empirical data. In addition, simulation results are given for the articulated vehicle equipped with a simple antiskid system.

The need to reduce the injury to pedestrians that are run over or pinned beneath a bus is an ongoing concern for transit authorities and other operators. Occasionally, a pedestrian will be run over by the right rear wheel while exiting the rear door. This accident occurs in various scenarios such as when people exit the bus and become entangled in the door grab bars, or when they fall between the curb and the bus while it approaches or departs. With all scenarios, the S-1 Gard acts similar to a cow catcher, pushing the fallen pedestrian out and away from the rear tire. This paper will: outline various incident scenarios, evaluate the S-1 Gard's performance in a city environment, review installation of the guard as well as its maintenance requirements. The purpose of this paper is to bring to the attention of transit authorities and shuttle operators the overall value of this device.

The Vehicle Energy Consumption calculation Tool (VECTO) is used for the official calculation and reporting of CO2 emissions of HDVs in Europe. It uses certified input data in the form of energy or torque loss maps of driveline components and engine fuel consumption maps. Such data are proprietary and are not disclosed. Any further analysis of the fleet performance and CO2 emissions evolution using VECTO would require generic inputs or reconstructing realistic component input data. The current study attempts to address this issue by developing a process that would create VECTO input files based as much as possible on publicly available data. The core of the process is a series of models that calculate the vehicle component efficiency maps and produce the necessary VECTO input data. The process was applied to generate vehicle input files for rigid trucks and tractor-trailers of HDV Classes 4, 5, 9 and 10.

As a non-predictive model of the scavenging process, a generalized thermodynamic model has been suggested. This model can give a thermodynamic description for any possible scavenging process. Having specified a history of the scavenging process, this model is suitable for all scavenging systems including cross, loop and uniflow scavenging schemes. For the simplified isobaric and isochoric model with respectively constant coefficients of intake and discharge proportions during different scavengine phases, analytical solutions for this model have been obtained. From these, all existing models with the isobaric and isochoric assumptions can be derived.

The use of instrumentation on agricultural equipment slowly evolved from human observation of the operation of the equipment to a level of instrumentation which parallels that found on automobiles, and shared that automotive plateau for approximately 40 years. It has now embarked on a path which differs from that of the automobile. These differences are now openly competitive within the agricultural industry in both the choice of display technology and in function selection. This paper reviews both the early and modern agricultural instrumentation along with some of the unique functions now being monitored.

The object of this paper is to review developments taking place in Europe on truck transmission design. The existing design principles used in synchronized mechanical transmissions are reassessed. A new approach where the main emphasis is given to synchronizer duty is described. The paper also discusses the logical extension of the use of stepped transmissions into semiautomatic versions and the possibilities of stepless transmissions.