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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.

Regulatory requirements in the European Union (EU) for off-road machines and road vehicles are different. Vehicles which transport passengers and goods, along with attached trailers, as well as road motorcycles must meet EEC type-approval requirements. All other types of self-propelled machines must meet the requirements of the Machinery Directive (Council Directive 98/37/EC), and the Electromagnetic Compatibility (EMC) Directive (Council Directive 89/336/EEC) and possibly other directives. This includes such categories as agriculture and forestry machines, construction machines, industrial trucks and similar products. The various directives outline the different processes for demonstrating compliance with the EU requirements. The intent of this paper is to summarize a few of the requirements that are of interest to off-highway equipment manufacturers and to identify some sources of information about the regulatory requirements.

The Nexus vehicle was designed and built for Transport Canada at the University of Saskatchewan to demonstrate that a safety compliant single passenger commuter vehicle could attain extremely low fuel consumption rates at modest highway speeds. Experimentally determined steady state fuel consumption rates of the Nexus prototype ranged from 1.6 L/100 km at 61 km/hr up to 2.8 L/100 km at 121 km/hr. Fuel consumption rates for the Society of Automotive Engineers (SAE) driving cycle tests were 4.5 L/100 km for the SAE Urban cycle and 2.0 L/100 km for the SAE Interstate 55 cycle. The efficiency of the power train was determined using a laboratory dynamometer, enabling the road test results to be compared to the results from an energy and performance simulation program. Predicted fuel economy was in good agreement with that determined experimentally. Widespread use of single passenger commuter vehicles would substantially reduce current transportation energy consumption.

Highway and roadway surface measurement is a practice that has been ongoing for decades now. This sort of measurement is intended to ensure a safe level of road perturbances. The measurement may be conducted by a slow moving apparatus directly measuring the elevation of the road, at varying distance intervals, to obtain a road profile, with varying degrees of resolution. An alternate means is to measure the surface roughness at highway speeds using accelerometers coupled with high speed distance measurements, such as laser sensors. Vehicles out rigged with such a system are termed inertial profilers. This type of inertial measurement provides a sort of filtered roadway profile. Much research has been conducted on the analysis of highway roughness, and the associated metrics involved. In many instances, it is desirable to maintain an off-road course such that the course will provide sufficient challenges to a vehicle during durability testing.

Overloading of trucks can easily cause damage to roads, bridges and other transportation facilities, and accelerate the fatigue loss of the vehicles themselves, and accidents are prone to occur under overload conditions. In recent years, various countries have formulated a series of management methods and governance measures for truck overloading. However, the detection method for overload behavior is not efficient and accurate enough. At present, the method of dynamic load identification is not perfect. No matter whether it is the dynamic weight measurement method of reconstructing the road surface or the non-contact dynamic weight measurement method, little attention is paid to the difference of different vehicles. Especially for different vehicles, there should be different load limits, and the current devices are not smart enough.

Prior to World War II, most heavy duty highway trucks and tractors were built as Conventionals, i. e., with the cab mounted behind the engine. In the late 1940's cab-over-engine types gained acceptance and in the 1950's the tilt cab COE was developed in its present form including sleeper cabs. The new concept is to combine the best features of conventionals and tilt cab COEs to develop a superior non-sleeper tractor that makes no compromises for sleeper cab types.

Road test simulation on test rig is widely used in the automobile industry to shorten the development circles. However, there is still room for further improving the time cost of current road simulation test. This paper described a new method considering both the damage error and the runtime of the test on a multi-axial test rig. First, the fatigue editing technique is applied to cut the small load in road data to reduce the runtime initially. The edited road load data could be reproduced on a multi-axial test rig successfully. Second, the rainflow matrices of strains on different proving ground roads are established and transformed into damage matrices based on the S-N curve and Miner rules using a reduction method. A standard simulation test for vehicle reliability procedure is established according to the proving ground schedule as a target to be accelerated.

Due to the variability of real traffic conditions for vehicle testing, real-world vehicle performance estimation using simulation method become vital. Especially for heavy duty vehicles (e.g. 40 t trucks), which are used for international freight transport, real-world tests are difficult, complex and expensive. Vehicle simulations use mathematical methods or commercial software, which take given driving cycles as inputs. However, the road situations in real driving are different from the driving cycles, whose speed profiles are obtained under specific conditions. In this paper, a real-world vehicle performance estimation method using simulation was proposed, also it took traffic and real road situations into consideration, which made it possible to investigate the performance of vehicles operating on any roads and traffic conditions. The proposed approach is applicable to all kind of road vehicles, e.g. trucks, buses, etc. In the method, the real-road network includes road elevation.

A one thousand horsepower machine to be used for milling and excavating concrete and asphalt pavement is currently being produced. The machine was designed primarily for large pavement removal or surface texturing jobs. This paper contains general description of the machine, its overall size, power distribution, drive configuration, etc. It is significant that the machine represents a proven, quick economically sound method of resurfacing, recycling, restoring and reclaiming our nations deteriorating highway system.

Overturning on a road turn has always been a problem in vehicles. Based on a half- vehicle model, the results of vehicle stability after incorporating a hydraulic-actuator system is analyzed. It has been shown in the paper that the stability of a vehicle on a road turn can be increased promisingly by tilting its body towards the inner direction. The results are compared with the corresponding results of a conventional vehicle. Because of the feasibility and effectiveness of the proposed algorithm, the above system shows a definite improvement in vehicle stability.

For years, producers of low to medium volume products of high unit cost have been faced with the questions-“How much do we test?” and “What if we don't?” Today, manufacturers cannot compete in the market if these questions are not answered. This paper presents a methodology for answering these questions quantitatively. It applies Bayes Theorem of “apriori knowledge” to generate a probabalistic model of the new product testing task. It uses the existing knowledge and expertise within the organization and a simple matrix technique to determine the testing needs for the project at hand. This paper is intended to address the issues of durability and reliability of new products that are manufactured in relatively low volumes, such as Lift Trucks and Farm Equipment and/or products of high unit cost such as construction or off highway machinery.

Transportation in the second half of this century tends towards employing large vehicles that offer cheap freights. Tied up to their century-old gauges, the railroads are the only exception. In Argentina, highway and railroad infrastructures mainly converge to fluvial ports which, owing to their lack of depth, cannot take in present-day vessels. This paper describes a fast wide-gauge train, which cannot be derailed or overturned; it shall enjoy a cheap t/km freight, cheaper than that of current trucks and trains, and even of river and ocean-going ships. It shall unite the North and South regions of Argentina as one backbone, and shall behave like a vast river or inland channel, linking it up with the Patagonian deep-sea ports, integrating and developing the country, which will cause its products to be competitive all over the world.

Applications of active suspension control for both on-highway and off-highway vehicles are reviewed. Suspension design is evaluated in terms of ride vibration exposure and road/terrain handling. Active, semi-active, and slow-active suspension types are described in terms of their performance capabilities. Finally, numerous design concepts and their application to a wide range of ground vehicle types (i.e, truck, automotive, agricultural, and construction) are described.

Japan's truck production in 1962 accounted for 70% of total vehicles manufactured. Of this, 85% consisted of compacts and midget models for use by private enterprises and over congested narrow roads. Because of severe operating conditions on unpaved bumpy roads, large payloads require sturdier vehicles and higher ratios of power to weight than do those in other countries. Passenger bus transportation is expanding and extending service distances. Practically all large vehicles are diesel powered, but smaller ones are gasoline powered. The modernization of highways will bring larger and speedier models with more engine horsepower for longer distances.

In the past, a vehicles ride had been evaluated subjectively which allowed many different interpretations of what the ride goal for a new vehicle program should be. With the advent of a ride metric system that evaluates ride based on customer input and provides an objective measure, we have been able to: Benchmark competitive vehicles, Define suitable road surfaces to evaluate, Define a target ride objective, Sort out various vehicle modifications, Track performance towards the objective throughout the development of a new vehicle. Now that an objective measure of ride has been established, ride and handling engineers will be much more effective in providing customers with the level of ride required on new product programs.

A road simulator system has been developed for heavy duty vehicles. The system utilizes vertical inputs to the tires and corrects for heavy duty vehicle simulation problems such as solid axle cross-coupling, different tire contact patches for front and rear tires, tire nonlinearity, and variation in vehicle speed. The system operates in two modes which allow reproduction of response measured on a particular road, or simulation of vehicle response to a class of roads described by a PSD Matrix. The road profile generation techniques for each mode of operation are described. These techniques determine effective road inputs from measured vehicle response through a multiple input-multiple output systems analysis of the vehicle. Laboratory test results for both modes of simulator operation are presented.

Right now, most of the industries are doing real world fuel economy test of their proto-types/mules by deploying them to city, state highways and national highways to declare their FE value. Which involves lot of unexpected problems, large amount of labor and the worst part is the pollution, traffic and uncontrolled randomness (difficulty in completing the test during festivals). Among already existing drive cycles, this is different because of a simplified mathematics of error and probabilities for method of cycle creation and it has been correlated with the real-world results. This paper reveals a 10-min city drive cycle which was created after studying most of the parameters of vehicle which may affect fuel economy and a whole method, which was devised to form this cycle and then to simplify it enough to drive.

Mountainous area makes up more than half of the whole land area of China, the road of which is full of ups and downs. Heavy commercial vehicles as the main means of transport in mountainous areas, braking torque recession, even brake failure, often happens because of the overheating in long downhill journey, which seriously threatens the safety of the driving. Therefore, this paper presents an intelligent assistance system based on Geographic Information System and vehicle dynamics. The main brake duration and heat generation can be effectively reduced through adjusting the speed at the slope top, applying the engine auxiliary brake in the initial stage and choosing braking strategy appropriately, in order to prolong the downhill driving distance and improve the safety during continuous braking. This paper characterizes and analyses the road gradients and their effects on braking heat generation.

An improved hydraulic suspension strut has been developed for applications on large mining dumpers. This dramatically improves the isolation of the structural components and operator from dynamic haul road effects and thus, increases productivity and machine life. The performance requirements of a suspension system are defined with a discussion of the development of a 190-ton dumper hydraulic suspension strut.