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Electric power steering is a technology that will define the future. It eliminates the need for a power steering pump, hoses, hydraulic fluids, and a drive belt and pulley on the engine. As a result, electric power steering is energy efficient and environmentally compatible - while offering extras like simplified tuning, packaging flexibility and engine-off steering assist. With superior performance, electric power steering will be the technology that challenges the familiar, 50-year-old concepts of hydraulics.

Catalytic converter substrates for automobile emission control have to operate under the hostile conditions of the automotive exhaust. This paper will first discuss the mechanical and physical properties to ensure durable mechanical function of the catalytic substrate and converter system. High temperature mechanical and thermal shock substrate requirements and properties will be discussed. The functionality of a catalytic converter is significantly influenced by the catalytic coating. At the same time, substrate characteristics as will be shown, also effect converter functional parameters like back pressure, light-off and conversion efficiency. The importance of the substrate parameters cell shape, cell density and substrate mass and their effect on thermohydraulic parameters like heat- and mass transfer factors for various cell structures and substrates will be presented.

Automotive catalysts deactivate by thermal and poison mechanisms. Thermal degradation reduces catalyst efficiency by both agglomeration of precious metals and by reduction in surface area of the washcoat. Engine oil derived poisons degrade catalyst performance by coating the outer surface of the washcoat. Numerous catalyst technologies are aged using accelerated dynamometer aging schedules that simulate the thermal and poison degradation of field aged catalysts. Pd, Pd/Rh, Pt/Pd/Rh, and Pt/Rh catalyst technologies are aged and evaluated on various rapid aging test (RATsm) schedules in an effort to ascertain what catalyst technologies may be best for low temperature and high temperature applications. The performance of these catalyst technologies are evaluated on an air/fuel sweep test and a 3.8L auto-driver FTP stand. Results show that the RATsm schedule applies a phosphorus poison distribution (due to engine oil consumption) similar to vehicle aged catalysts.

In some important situations a structure and joints within it are required to collapse in a controlled way so as to absorb energy and mitigate the effects of the impact loading. Under rapid collapse in a crash situation, the behaviour of the joints forming a structure can be different to that of the statically loaded case. In this paper, an experimental investigation is described which explores the behaviour of lap joints under dynamic conditions. It was found that the failure modes are insensitive to the test speed although the absorbed energy and mean loads increase significantly with respect to the test velocity.

The growing proportion of comfort equipment and electronics in modern vehicles results in the fact that increasingly extensive tests and parameter setting tasks occure at the end of line. With the concept of the end of line tests of today, which means use of highly specialized single test stands, these requirements can no longer be complied with. The trend is towards flexible test stands designed according to the vehicle equipment and the test profile. This results in a test concept in which the tests are no longer carried out by the control of the respective test stand but by the vehicle's ECU. In the first step, this isa mobile test unit which communicates directly with the vehicle's control device and automatically generates test programs which are worked-off with the help of the respective test stand. Apart from performing the test itself, this unit also sets the parameters of the ECU.

During SAE BRASIL/96 a paper was presented showing that it was possible to represent the influence of the coefficient of friction in the stamping process using numerical simulation and some results were shown where it became clear that the correct definition of the friction conditions is very important for the results reliability. It was also shown that the current practice of assuming a typical value for the coefficient of friction, independent of the lubrication conditions, can lead to imprecise results. Along the drawing operation, the blank contacts different regions of the die and for each region there are different contact conditions (contact pressure, sliding velocity, etc.). These differences can lead to friction conditions where the coefficient depends on the contact variables and the Coulomb friction model is not applicable.

In this paper, we analyze a McPherson vehicle suspension from the point of view of vibration transmission to the body. We developed a simple linear mathematical model to study how the characteristics of the components of the suspension (spring, shock absorber and upper mounting) affect vibration's transmission. Finally, we experimentally verified one of the adopted solutions to lower the level of vibrations and the level of interior noise of the vehicle.

Due to the growing need to reduce the development time of new products, a tendency to rationalize field tests through test benches, in shorter times and with lower costs, has been noted in recent years. During the 90's, such a tendency has generated, in the automotive industry, a great effort to substitute classic field tests, which until recently represented 70% of the development work, for bench tests, with benches well “calibrated” in relation to the traditional methodology. The present work intends to show the development of a test bench to simulate solar radiation and relative humidity effects upon parts and interior lining materials of truck cabins. The traditional test was carried out exposing the cabin to weather conditions in predetermined locations, or in a hot-house, monitoring the cabin interior for temperature and relative humidity variations.

The MacPherson strut is an excellent solution for front wheel drive suspensions that has been used worldwide by car manufacturers. Besides the advantages of this suspension it presents many difficulties due to the characteristic of being a bending structure. Little attention has been given to the contribution of the MacPherson strut flexibility to vehicle dynamics. The flexibility of the structure affects the suspension geometry, mainly the camber angle, and this influences the vehicle handling and the driving safety. It is presented the effect of forces and bending moments on the piston rod, reservoir and pressure tubes and their contributions to the suspension flexibility. It is discussed the effect of the several standard piston rod diameters commonly used and the influence of the variation of the bending resistance arm. The effects of other parts are also analyzed, as the tensile strength, design safety factors and other important data.

In our permanent and continuous work to fulfill customers expectations and get their enthusiasm. GM of Brazil has put strenuous efforts to improve the vehicles quality. “The major drive of change for General Motors today is the same as for most companies: its globalization. Advances in technology and communication are making the ‘small world’ a reality,and the world will only get smaller and smaller in coming years.

Recent studies in the USA show 2800 passenger casualties/year, due to automobiles and light vehicles impacting against the front structure of medium and heavy trucks at speeds over 45 mph. This same driver or passenger leaves the vehicle and becomes a pedestrian. What is being done in the automotive industry to face this situation? What improvements can be expected in automobiles, trucks and buses in the XXI century? The results obtained in this work show that it is possible and very important for new projects and modernization of commercial vehicles (trucks and buses) to introduce a front bumper concept foreseeing the Passive Safety of third parties (passenger vehicles).

The present work was aimed at evaluating, on a bench scale, the influences of the operation temperature and the Ca/S molar ratio in the fraction of SO2 removal in a continuous binary fluidized bed reactor, through a reaction with dolomitic limestone. It showed a significant contribution of the added Ca/S molar ratio for the 500-600°C range, as well as the strong influence of the temperature in the gas removal fraction for the 550-700°C range.}

Through numerical simulations of a cyclist+bicycle system, a performance comparison was carried out between a traction drive continuously variable transmission (TD-CVT) and a traditional transmission (step-variable transmission) for bicycles. The objective was verifying the performance of both of them when the cycling frequency was kept invariable. For that, the principles of a TD-CVT were initially described. After that, the human characteristics of producing power in different intervals of time were considered. Then, the cycling frequencies which are most commonly used in biomechanical tests related to cycling were analyzed. Finally, the cyclist-bicycle system was modeled through Lagrance's movement equations. During the simulations, the cycling frequency values and the description of the transmissions used in a certain course were stored in order to be compared.

The main objective of this work is the structuration of a complete software for reliability analysis of mechanical components, as well its application in failure tests to obtain useful lifetime employed in some advanced maintenance techniques. The software has a theoretical revision for better understanding of the basics concepts of reliability and it presents procedure to evaluate reliability functions through the main statistical methods. Making use of the statistical theory applied to components and systems trials, the most common types of trials and their application to the sample population were studied. Basics concepts as parametric and non-parametric trials and descriptive statistic are applied. Afterwards, it was made an analysis of correlation and regression of the obtained data from the trials and curve fitting (lineal, logarithmic, exponential, etc.).

The objective of this paper is to study the design characteristics more viable to build an autonomous vehicle for disabled people (AVD). In this paper, some components are examined for available options and how these options effect the performance of the vehicle. Besides, the dynamic model of a tricycle configuration of AVD is shown. The equations of motion governing the behavior of the vehicle are obtained with the Newton and Euler's equations. Through the dynamic equations, the analyses of dynamic stability and dirigibility for the configuration are made and compared with other configurations with different kinds of driving and steering. Considering the results of stability and dirigibility, a fuzzy controller for navigation and obstacle avoidance control is design. The fuzzy controller was simulated and the results indicate that it is better use the velocity control only on final approach to goal position.

This work is concerned about the conception of computer programs to aid the process of mechanical design. Today it urges the development of systems that works further than the traditional areas dedicated by CAD systems (Computer Aided Design) that are the area of draft. CAD systems must aid in the conceptual phase of design. This paper presents the development of a software system as a solution to this problem in design field. It was developed in visual object oriented language, and it was split into 3 modules with tasks of: design process management, requirements determination and conception development.

Multifunctionality for release agents is a requirement to ensure the quality of the product, mainly in automotive components molded with Integral Skin Polyurethane Systems. This multifunctionality comes from a synergism of various release agent characteristics and process related factors, allowing to obtain components with the visual aspect and properties required. The constant development of base raw materials and solvents in the release agents together with new spraying techniques ensure that the multifunctionality will be always present generating new and efficient release agents that preserve the environment.

A new system of actuation of the clutch release bearing was developed, that became promising for the evolution of its assembly in application on passengers cars. This central hydraulic actuation system came to revolute the automotive components industry and complete the cycle of evolution of the clutch release bearing as we know it today. The application of modern projects technology, the calculation of the state of the art to fatigue, systems of computer aided drawings (CAD) associated to intense materials research, made possible an evolution that can be expressed in performance terms. The utilization of engineering plastics in these systems and the technology of transformation of steel bands through the drawn cup process is particularly noted. The association with developments in actuation systems brought a considerable gain in energy saving, space saving comfort, safety and reliability, and cost reduction.

The lag inside shock absorbers is a very undesirable problem. Lag can hinder shock performance by interfering with the forces that control it. Unfortunately, lag is a frequent problem, for that reason, we decided to study it, we hope to understand its causes and implement solutions.

Using new process and new assembly concept, where P.T.F.E rings are directly molded in the piston it because possible to obtain a considerable gain in the rebound forces of shock absorbers This gain is obtained by a better ring anchorage, less dimensional variation when assembled to the piston and using a flexible skirt that warrants a complete piston sealing in respect to the pressure tube.