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A new way of representing tyre data obtained from measurements in pure cornering and pure braking conditions has been developed in order to further improve the Dynamic Safety of vehicles. The method makes use of a formula with coefficients which describe some of the typifying quantities of a tyre, such as slip stiffnesses at zero slip and force and torque peak values. The formula is capable of describing the characteristics of side force, brake force and self aligning torque with great accuracy. This mathematical representation is limited to steady-state conditions during either pure cornering or pure braking and forms the basis for a model describing tyre behaviour during combined braking and cornering.

In light of the drive for energy efficiency and low CO2 emissions, extensive research is performed to reduce vehicle aerodynamic drag. The wheels are relatively shielded from the main flow compared to the exterior of the passenger car; however, they are typically responsible for around 25% of the overall vehicle drag. This contribution is large as the wheels and tyres protrude into the flow and change the flow structure around the vehicle underbody. Given that the tyre is the first part of the wheel to get in contact with the oncoming flow, its shape and features have a significant impact on the flow pattern that develops. This study aims at identifying the general effects of two main tyre features, the longitudinal rain grooves and lateral pattern grooves, using both Computational Fluid Dynamics (CFD) and wind tunnel tests. This is performed by cutting generic representations of these details into identical slick tyres.

Intensified search for alternative fuels is the main interest across the world due to the impact of fossil fuel crisis, ever increasing vehicle population and oil price and stringent emission norms. On the other hand, the disposal of waste tyres from automotive vehicles becomes complex. Apart from alternative biomass derived fuels like Ethanol, Methanol, Hydrogen, Vegetable oils etc, the new sources for alternative fuels are also appreciable. In this context, Pyrolysis of solid wastes is currently receiving renewed interest. The disposal of waste tyres can be simplified to some extent by Pyrolysis. In this paper, the properties of the pyrolysis oil derived from the waste automobile tyres were analysed and compared with the petroleum products and pure rubber pyrolysis oil. Also, Tyre pyrolysis oil-Diesel blends were used as alternate fuel in a four stroke Diesel Engine without any modification in the engine and the performance and emission characteristics have been studied.

Intelligent tyres can offer crucial insights into tyre dynamics, serving as a fundamental information source for vehicle state estimation and thereby enabling vehicular safety control. Among the numerous tyre parameters, slip ratio stands out as a direct influencer of vehicle motion characteristics. Accurate estimation of tyre slip ratio is essential for vehicle safety. Firstly, an analysis of the fundamental composition of tyres was conducted, and appropriate simplifications were applied to the tyre structure. Additionally, a finite element model of the tyre was constructed using ABAQUS software. To validate the reliability of the model, a real vehicle testing system was established, consisting of the experimental vehicle, data acquisition system, and supervisory computer. The reliability of the finite element model was confirmed by assessing the consistency of acceleration signals in three different directions of the tyre.

A new laboratory has been built to carry out research and development into the noise, comfort and handling characteristics of pneumatic tyres, and to produce the optimum matching of tyres to vehicles. The vehicles covered range from cars to the largest trucks. The equipment includes rolling roads fitted with various road replica surfaces for noise and comfort testing. Single tyre testing is carried out on laboratory suspension units. Multi-channel real-time analysers are used to process the information from accelerometers and microphones. Special test techniques have been developed to produce the ranking of vibration transmission through the various paths between the road surface and vehicle occupants. For handling evaluation, cornering characteristics of tyres are measured by the Dynamics Machine. These are correlated with proving ground instrumented tests in mathematical simulations; the vehicle characteristics for these are measured on the Vehicle Inertia Rig.

The tyre industry faces high expectations to design and produce tyres that meet the continually stringent tyre-road noise level requirements. With increasing market pressure, the demand for low noise tyres is on the rise. Since tyre prototyping is an expensive and time-consuming process, a robust method for the prediction of tyre-road interaction noise using simulation techniques is required. Based on the physical mechanism, tyre rolling noise sources can be broadly divided into structure based wall vibrations and fluid induced tread pumping sources. In this work, a combination of structural and acoustic FEA based simulation methodology has been used for the prediction of tyre tread pattern noise. First step of the methodology is an explicit structural finite element simulation, which is used to obtain the nodal displacements of the tyre. The results of this first calculation are then used in a second step in the frequency domain.

The generation and propagation of noise from vehicles is governed by several different mechanisms, but it is mainly produced by motor vibration at speeds below 50 km/h and the tyre/pavement contact at speeds above 50 km/h. In the latter case the noise can be mitigated through the use of special asphalt mixes. This study evaluates the sound absorption coefficient, using the impedance tube method, of different types of asphalt mixes (common dense asphalt mix, dense mix with asphalt-rubber, coating of drainage mix with voids and porous friction layer, the latter two with rubber asphalt). The results show that the sound absorption coefficient is dependent on the volume of total and interconnecting voids as well as the thickness of the sample.

Tyre road noise today has become an important subject for the design of quieter vehicles and for the protection of environment. Tyre design (Tread pattern geometry) and Road surface (microstructure), both are responsible for noise generation and thus there is a scope of reducing the noise through joint work. The purpose of this paper is to review and discuss the dominant mechanism (excitation/vibration) which generates tyre noise, its prediction techniques and pattern geometry of the tread responsible for it. The work uses virtual tool in a computer environment which predicts the pattern noise (exterior) and the data is correlated with the experimental noise (measured in an anechoic chamber on a dyno) which helps assess the behaviour of a pattern before an actual prototype is built. This helps compress design cycle time of a new tyre. Tyres with different pattern geometry have been considered to show the effect of geometry on noise generation.

This paper is a study of the changes that have been incorporated in passenger cars sold in the U.S. in recent years to improve fuel economy, and of the significant improvements that have been achieved. Promising areas of new technology are also described that should have the capability of providing further substantial fuel economy improvements. Market acceptance, economic considerations, potential government actions and other factors that may affect fuel economy are also discussed. Although this study is focused on U.S. passenger car developments, the results should also be of relevance in Europe. For consistency with U.S. legislated requirements, fuel economy values in the paper are in miles per U.S. gallon; corresponding fuel consumption figures in litres/100 km are also shown.

Side impact field crashes from the University of Michigan Crash Injury Research and Engineering Network (UM CIREN) database were studied in detail. These cases involved seriously injured occupants that spanned 1997 - 2006 model year vehicles. Specific injury risks are not presented because the database used was populated only with occupants requiring treatment at a Level 1 Trauma Center. This study analyzes side impact collisions for AIS ≥ 3 injury patterns in crash configuration, injury contact locations, gender and by age. Field crashes were also categorized into those that represent existing standard side impact laboratory test methods. Over half of the cases were identified as collisions into the passenger compartment with occupants seated on the near side of the vehicle closest to the impact, which is consistent with current standard laboratory tests. The next two largest categories involved either far-side occupants or impacts primarily centered onto the engine compartment.

This paper presents a method of using CAE to determine the pre-load and torque applied to a U-Bolt rear Spring Seat. In this paper it is review two U-bolt design and the stresses generated by the pre-load torque applied, based in this study a process to determine the minimal preload and the torque is discussed. By this process it is possible to determine the minimum Torque and the correct pre-load in the U-Bolt element and assuring the correct fastening of the components avoiding over stress in the Bar elements.

Motorcycles arrange the radiator in front of the engine. So, the size of radiator is not wider than the width of engine or the width of frame. We design the motorcycle similar to road-racer. We hope that the width of radiator is as narrow as possible, because motorcycle can run as fast as possible. So, it is necessary that the width of engine and frame is narrow as much as we can, and the width of radiator is limited. But for the water-cooled engine, the temperature of coolant has better be low so as to product the effective combustion. So, it is necessary that the width of radiator has better be wide, but it contradict the above. “U-Shaped Radiator” solves the above problem. The structure is that radiator bends U-form in the front of motorcycle. Now we can improve the cooling performance (+30%) in comparison with the same width radiator.

Two aspects of electric vehicle development in the UK are discussed; vehicle chassis, hardware and battery development and operational experience. Electric delivery vans of the one to two ton payload range in the Lucas and Chloride programmes are discussed. The improving prospects for molten sodium sulphur battery in large vans and buses is examined. The GLC ‘London Goes Electric’ scheme for placing up to 62 vehicles in service in Central London is covered in addition to the Electricity Council trial of 60 Enfield city cars.

Voice technology provides a potential for alleviating the extremely high visual and manual workload of Army helicopter pilots. Before voice technology can be successfully employed in the cockpit, there are many human factors issues that must be resolved. This paper describes the approach used to identify potential applications of voice technology in an Army helicopter and the emulation of a voice interactive doppler navigation set.

This paper summarizes the present state-of-the-art in U. S. Army research in electrical vehicular propulsion systems. The powerplants discussed are: compression ignition and spark ignition engine generators, hybrid engines, turbine generators, Stirling engines, Rankine cycle engines, fuel cells, and batteries. The liquid hydrogen fuel cell offers the greatest potential for military applications because of the compatibility of the fuel. Also covered are the power conditioning units and drive units. The authors discuss in detail the five electric propulsion test beds being used at USAERDL: the BEST, ultra high speed, a-c electric wheel, d-c brushless and fuel cell.

Development of the U.S. Army's 1500-shp advanced technology demonstrator engines was initiated in 1967. Presented are several lessons of a technical and nontechnical nature learned from the program. Several problem areas encountered are highlighted and analyzed. Reflected is the need for standardization within the industry of methods of bookkeeping component efficiencies and of conducting engine performance analysis. Scheduling, development approach, and instrumentation experiences and requirements are also discussed.

The Body Division of the Automotive Corrosion and Prevention Committee of SAE (ACAP) has conducted biannual surveys of automotive body corrosion in the Detroit area since 1985. The purpose of these surveys is to track industry-wide corrosion protection improvements and to make this information available for public consumption. The survey consists of a closed car parking lot survey checking for perforations, blisters, and surface rust. This paper reports the results of the seven surveys conducted since 1985.

Automotive fuels are reviewed from the perspective of the declining petroleum demand and prices of I982. For the next 20 years, petroleum will remain the predominant source of automotive fuels worldwide; U.S. petroleum imports and their vulnerability to interruptions will be lower than in the late 1970's. The U.S. production of natural gas may exceed that of petroleum and will be supplemented by relatively secure imports. Barring major disruptions in the Middle East, or a strong OPEC, the rate of U.S. petroleum price increases will match or slightly exceed that of inflation. Consequently, in the near future fuels from coal, oil shale or biomass will be unattractive for private investment in the U.S. under [illegible]ree-market economics. This pessimistic forecast may not apply to methanol because of the high efficiency of methanol engines and the potential for lower methanol costs. However, coordination of methanol and methanol-vehicle production and distribution rates are problems.

The General Aviation safety record through 1970 is discussed, both statistically and in the non-quantitative sense. Related functions of the cognizant aviation accident investigatory agency, the National Transportation Safety Board, are also reviewed to place the data in proper perspective. Finally, a matrix is provided as an outline for participants in the General Aviation system to assess their own contribution to accident/injury prevention in this most rapidly growing segment of aviation.

In order to formulate policy for the orderly development and use of the nation's navigable air space, federal agencies such as the FAA and the Department of Transportation have launched several programs to determine aviation requirements for the next 10 years. This paper outlines their conclusions concerning airborne activities such as flow control, approach and departure control, wake vortex problems, and operating procedures as well as airport capacity and ground operations. The impact of the FAA's Research and Development Program and the implications of the current fuel shortage and economic situation are also discussed.