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Environmental stress crack resistance, ESCR, of several candidate plastics for instrument panels was studied using both constant load and constant strain methods. Poly-carbonate/ABS blends demonstrated significantly better ESCR properties than the polystyrene modified polyphenylene oxide system. The mechanism of failure was followed using SEM microscopy which showed that the load carrying phase was polycarbonate. Furthermore, a fracture mechanics study under dry conditions and in the presence of the aggressive environment was done. The data, based on the critical stress intensity factor in and away from the stress cracking environment, explains the behavior of polycarbonate/ ABS blends relative to the modified polyphenylene oxide system.

There can be no control over environmental pollution without methods for measuring how the environment is being affected by mankind. Consequently, when traffic noise was identified in 1964 by communities as an important form of pollution, it became necessary to measure the amounts of noise present and to assign relative importances to various sources in vehicular traffic. Truck tires were identified as being significant contributors and engineers from the tire and truck manufacturing industries acting under the auspices of the SAE set about to develop a test procedure that satisfied the immediate need - to initiate control over truck tire noise. This paper is a review of the outcome of that effort by one who participated in the earlier work on the testing standard. How well the method works, and how well it serves to meet the objectives now on the horizon are the preliminary topics of this discussion.

EQD-6102 diesel engine was developed on the basis of EQ-6100 and EQ-6105 gasoline engines. It has the direct injection W-type combustion chamber whose power performance is very close to the original gasoline engines. It has good economy, low speed torque property, acceleration performance and low noise. It has been proven that it works reliably and conveniently after continuous improvement and batch production. So EQ-6102 has won favourable comments from the end users.

The equations of motion of the two degree-of-freedom model of a two-axle road vehicle are expressed using vehicle cornering stiffness constants, which shows the effect of speed more clearly than stability derivatives. The forms of the equations of motion, for analysis in earth-fixed axes and vehicle-fixed axes, are compared. The properties of the characteristic equation are analysed by analogy with the single degree of freedom vibration equation. The undamped natural frequency, damping ratio and damped natural frequency are investigated. A simple extension of the model is considered, allowing inclusion of effects such as roll steer.

A methodology is presented for the design of vehicle suspension systems that vastly reduces the iteration required to achieve a given elasto-kinematic performance target. At the heart of the technique is the concept of an Equivalent Elastic Mechanism (EEM); a simple and intuitive mechanism, which can always be configured to replicate perfectly the elasto-kinematic behaviour of any compliant linkage, irrespective of its complexity. The paper describes the concept of the EEM, its derivation and different methods for its visualisation. Furthermore, it shows how an “ideal” EEM can also be calculated from an elasto-kinematic specification and how this EEM can be used to select and configure an appropriate suspension architecture.

Regarding a rubber seal used between a cylinder head cover and a sparking plug tube of an automobile, the author couldn't calculate escape load of the rubber seal in the head cover casing, because rubber friction coefficient and Young's modulus on the escape load was unknown. The effect of the measurement method of rubber friction coefficient and Young's modulus on the escape load, and method of measuring this escape load will be described in this report.

It has been reported that engine oils containing magnesium detergents gel under special conditions. The authors have previously reported on the mechanism by which magnesium detergents form needle crystals, which is the main cause of the gelation[1]. For this article, the authors conducted tests in actual vehicles using several types of engine oils containing magnesium detergents, including oils for which gelation problems have been reported in the market. The gelation was reproduced, and the test oils were ranked by their propensity to gel. In addition, a laboratory test method was used in which water and CO2 were mixed into engine oil under controlled conditions, then left stored in a bottle for twenty days, after which the kinematic viscosity and the quantity of insolubles of the mixture were measured. The study demonstrated the correlation between the laboratory test method and the actual vehicle tests.

This paper presents a new method for estimating the ambiguous change in a 4WS control system using a failure detection filter. This filter is designed to discriminate ambiguous failure modes in the control system by processing output errors between sensors and an observer. The result of the experiments using a 4WS vehicle revealed that the filter can estimate the failures of the sensors and the actuator with high accuracy. The effects of a lateral wind and other disturbances on the filter were also clarified.

Seat Effective Amplitude Transmissibility (SEAT) values can be obtained from direct measurements at seat track and top or estimated from transmissibility data and seat track input. Vertical transmissibility was measured for sixteen seats and six subjects on the Ford Vehicle Vibration Simulator, and these 96 functions used to estimate the seat top response for rough road input. SEAT values were calculated, and good correlation to values computed from direct seat top measurements obtained (R2 of 0.86). Averaging transmissibilities and direct seat measurements over the 6 subjects to obtain correlations for the 16 seats improved R2 to 0.94, validating this approach.

This paper presents the results of research, whose aim was to design and build a prototype device for the estimation of traction parameters of a car, including power output from engine. The estimation of the power of the powertrain system follows on the basis of measurements of the car's longitudinal acceleration in a special road test in actual driving conditions. The measurement of the longitudinal acceleration brings a number of problems which were solved due to the application of the new measurement method. The factors affecting deficiency of the precision of measurements and the methods applicable for its reduction were developed. As a result, it was possible to obtain a measurement method with reduced uncertainty and increased repeatability in terms of results. In addition, an interpretation of the results of the test is presented in reference to the power of the powertrain and engine.

One of the latest off-road, rear dump truck developments in the earthmoving industry is GMC Euclid Division’s R-X truck, an all-wheel drive vehicle capable of hauling pay-loads up to 105 tons, at speeds of 53 mph. The R-X truck incorporates many innovations new to off-road truck design. A hinged frame, pivot steering arrangement, and equal load distribution on the two drive axles provide exceptional tractive effort and maneuverability. It reduces tire scrubbing in turns, which has been a major contributor to excessive tire wear, and allows the use of smaller tires, which lowers load height. Also unique in the R-X truck design is the suspension system which features the use of a patented “A” frame axle mounting which maintains axle alignments while permitting oscillation against stacked rubber disc spring members.

Contrary to the Japanese and American markets, the European market for Diesel-engined passenger cars has experienced a strong growth which today is tending to stabilise. This article proposes to analyse this market, including comments on the performance and engine technology associated with this market explosion. The accent is placed also on the efforts of the manufacturers to improve the Diesel engines quality of function, linked to the fuel quality, and on the drive to make the Diesel competitive with the gasoline engine. The consequences of more severe emissions regulations on the characteristics of the engines and the systems which control them, including the adoption of the injection flow and timing device, are also treated. A rapid analysis of the changes in the domain of utility vehicles is presented.

“Without lubricants, all the machines in the whole world would grind to a halt”. This often used sentence, summarises rather well the increasingly important role of lubrication in our modern world in constant evolution.

A specific objective of the European Mg-Engine project is to qualify at least two die cast Mg alloys with improved high temperature properties, in addition to satisfactory corrosion resistance, castability and costs. This paper discusses the selection criteria for high temperature alloys leading to four candidate alloys, AJ52A, AJ62A, AE44 and AE35. Tensile-, creep- and fatigue testing of standard die cast test specimens at different temperatures and conditions have led to a very large amount of material property data. Numerous examples are given to underline the potential for these alloys in high temperature automotive applications. The subsequent use of the basic property data in material models for design of automotive components is illustrated.

EUROSID is the side impact dummy that has been designed and has now been almost completely developed by a group of European research laboratories working together under the auspices of the European Experimental Vehicles Committee (EEVC). It represents a bringing together of components and ideas from the three experimental sided impact dummies sponsored by the EEC1 as part of their Biomechanics Programme. These were produced by APR (Peugeot-Renault), ONSER, and MIRA. This paper describes the evolution of the EUROSID dummy and discusses the advances in biofidelity, the responses of its various components to impact, and the types of measurements it can record.

We studied the mechanism of occurrence and evaluation of the surge that is produced in motorcycles equipped with 2-stroke cycle engines by simultaneously measuring chassis behavior and combustion. When modal analysis was performed by measuring the acceleration of each chassis component while placing the test vehicle on a chassis dynamo, it was found that pitching, in which the tires serve as springs, and resonance, generated from the rear suspension spring, occurred simultaneously during surge generation. The major component that is felt physically is pitching. Although a certain degree of correlation was observed between fluctuations in combustion and occurrence of pitching, since the drive line contains a large amount of back lash, the system has a high degree of non-linearity, thus making it difficult to obtain a well-defined correlation.

Nations around the world have implemented various policies to control and manage air quality but VOCs (volatile organic compounds) aldehydes, and micro hazardous air pollutants are not subject to strict regulation compared to other exhaust emission sources of passenger cars. In this regarde, this study was conducted to evaluate how hazardous pollutants from passenger cars contribute to air pollution using gasoline and LPG fuels. For the study, a passenger car with GDI(Gasoline Direct Injection) and one with the LPI(LPG Port Injection) system were selected to evaluate the contribution rate of hazardous pollutants. Catalyst temperatures were measured for the prevention of emission variation in the process of stabilizing the catalyst and the modal data from the test mode was validated by using a chassis dynamometer (Horiba).

On the basis of existing methods, a new method of evaluating ABS performance is proposed in the paper. This method can evaluate lateral stability of vehicle during vehicle braking process. It is verified by simulation. The most advantage of this method is that it can evaluate the performance of ABS during design phase. It also can short the developing cycle of ABS, and save the developing expenditure of ABS. This method can be applied to the design and simulation study of ABS.

Since the Adapted Frontlighting System (AFS) was commercialized in 2003, it has helped improve visibility on curves. This paper reports that: The driver’s eye-fixation points change for different areas on a curve. This was found by observing the driver’s gaze behavior in horizontal directions and the road geometry of curves; and There is a correlation between the gaze behavior in horizontal directions and the headlamp lighting, AFS lighting in particular. This correlation was used to evaluate the AFS lighting performance.

In this paper three evaluating parameters for cam lubrication characteristics in I.C. engine are introduced, namely the lubrication characteristic number Ns, the hydrodynamic characteristic number Nγ, and the non-dimensional lubrication characteristic number N̄s. The relations among them are deduced. From viewpoint of lubrication some basic points for the design of the cam profile are presented. The requirement for the condition Ns =0 is also proposed, i.e. (dNs /dϕ)Ns =0 ≥3mm/°. These evaluating parameters for cam lubrication characteristics of several current I.C. engines are computed, and finally some conclusions are drawn.