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Brazil, that presents one of the highest accidents indexes of the world, does not have any specific regulation related to the use of an external light during the day time which provides a better visibility of the vehicle in movement and according to studies gives more reaction time for the other road users. Many countries in Europe and North America shows good results since they adopted the lights on during the day with collision reduction of vehicle to vehicle, vehicle to pedestrian and vehicle to cyclists. The aim of this study is to show the benefits of the Daytime Running Lights (DRL) and its relation to the reduction of the traffic accidents, as well as a brief analysis on the use of a dedicated system, which can be more efficient since it can be designed to provide a light distribution allowing a better visibility as possible.

Normally the automaker uses a specific Engineering criteria for serviceability with minimum clearance specification. Due to Front Over Hang reduction (Figure 1) regarding to Emerging Markets countries and technology inside in the hood compartment, the H4 bulb serviceability is affected. This paper shows a solution that provides an easy service procedure reducing package and complete sealed connector system for an H4 head lamp bulb. Figure 1 Front over Hang Reduction.

On Current Automotive Application, including Brazil, there are significant initiatives to reduce fuel consumption and emissions, like INOVAR Auto and others worldwide. There are several initiatives for Hybrid vehicles, electrical vehicles and other fuel cell energy vehicles, besides the additional energy supply in order to reduce the fuel energy consumption and consequently the emissions. The vehicle features represents a huge part of energy consumption, because the generator needs to feed all of those features. To reduce this energy required from generator and consequently from vehicle accessory drive and engine itself, we are aiming to reuse one of the bigger energy wasted on vehicle combustion engine, the thermal one. For that end, the Thermal Energy Generator is applied on major heat sources and convert the thermal energy through electrical energy due to “See-beck effect cells”.

In recent past years, the most important challenges for car manufacturers in terms of crashworthiness have been related to the introduction of the Frontal Small Overlap crash test promoted by the IIHS. The introduction of this new configuration presents a new and critical load case that manufacturers are on the way to solving. Now, with several OEM's starting to achieve good results, a new configuration is being studied for introduction: the frontal oblique crash test against a deformable barrier based on the National Highway Traffic Safety Administration (NHTSA) proposal in the US. Towards providing the best tools for passive safety development, a tool to enable the analysis of the loads transmitted to the barrier in both tests has been developed.

According to the “Report 2010” of the Association des Constructeurs Européens de Motocycles (European motorcycle manufacturers' association), the number of motorcycles throughout the European Union rose from 16 million to more than 22 million between 2001 and 2008. Taking all two-wheeled motor vehicles into account, in 2008 approximately 33 million vehicles were registered. At the same time, motorcycles are by far the most dangerous means of transport. Two groups (children and elderly people) are especially vulnerable due to their weakness against impact, reflexes and reaction to risk, resistance to the generated forces, etc. According to the latest accidents data from the European Community database on road accidents (CARE), more than 110 children under 14 years old who were passengers on PTW's were killed on the roads of the Community between 1991 and 2000.

The clutch actuation system has the function of convert force made by the user on the pedal to a force acting on the clutch fingers. This system is compound with many components and one of than is the clutch release bearing. The clutch release bearing has direct contact with the finger of the clutch and materials in contact suffer a relative motion. In some case this relative motion is desired and other undesired. Thus this contact surface and the relative motion are important parameters to correct operation and to avoid wear. This paper will study the contact mechanic of this system and for this a large bibliographical review will be made and rise. Basic models and simulations will be developed to visualize the behavior of this system and also some experimental test will be done with different contact surface. This work will help to better understand the contact behavior and design contact geometry for minimum wear.

Vehicular emissions limits have been reduced throughout the world in compliance with environmental legislations. With the rapid increase in the number of flex-fuel vehicles on the market, the consumption of ethanol has also increased. As a result, there is expected to be a large abundance of unburned alcohol from tailpipe gas emissions. Another important factor arising from the use of ethanol is the formation of tropospheric ozone. The objective of this study was to measure the amount of unburned alcohol and legislated emissions as well as the ozone formation potential of a passenger (light-duty) vehicle fueled with gasoline containing different concentrations of ethanol. The main conclusion is that unburned alcohol emissions increase in direct proportion to the ethanol content in the fuel. The unburned alcohol was measured by two techniques: gas chromatography and FTIR.

In order to have a windshield wiper system according to wiped area and kinematic behavior requirements since the early phases of vehicle development, this paper makes use of a MATLAB optimization function to optimize the windshield wiper system. The main goal is to achieve the maximum wiped area by optimizing wiper blades lengths and orientations. Parallel to that, constrains make the method finds the optimum kinematic design for the windshield wiper linkage in terms of mobility, available area to fix the linkage on body and the maximum range of the blades oscillatory motion. This optimization is applied on an existent windshield wiper system of a domestic passenger car to present the benefits of the developed model.

Nowadays, due to the global warming questions related to CO2 emissions, many countries legislation lead automotive and fuel industries to search for higher efficiencies in their products. Therefore, new engine technologies and cleaner fuels are being developed and launched in the market. This paper presents a study of efficiencies on chassis dynamometer tests, in order to evaluate vehicle and fuel contributions. Tests were performed using one Brazilian flex fuel vehicle in full load condition at constant speeds to evaluate the losses of each part of the system, such as, wheel, air resistance and powertrain. The vehicle energy parcels were determined. So, it was possible to assess vehicles mechanical losses, aerodynamic losses and also the engine efficiencies.

The detailed study of cosmic ray's influence is recent, as well as the invention of the transistor. Ionizing particles from space that focus on silicon integrated circuits (IC) can cause many undesirable effects. These particles are mainly from solar activity, and can be classified into two basic groups: charged particles, e.g, electrons, protons or heavy ions, and electromagnetic radiation (photons), as X-rays, Gamma -rays, or Ultraviolet (UV) light. When they collide in an IC, these energetic particles cause a current pulse, which can affect the correct functioning of the device. These electronic circuits have become increasingly susceptible to the effects of radiation, due to miniaturization, thus increasing the incidence of failures.

Changes in the macro economic scenario of Brazil during the latest 10 years resulted on several changes in the auto industry market. One, which affected important requirements of the light duty trucks, regards the migration of customers from passenger car segments to light duty pickups. A considerable portion of these new pick-up customers expects an overall level of comfort, handling, noise and vibration similar to the levels found in passenger cars. One possible conclusion of this trend is that an optimized vehicle system integration is vital to prevent potential issues and to assure the achievement of customer satisfaction. Among several vehicle systems, the Drivetrain integration deserves the major attention. This paper shares lessons learned on the integration of the manual Transmission, external shifter, mountings, propeller shaft, rear axle and suspension with the rest of the vehicle.

Nowadays, the influence of aerodynamics on vehicles capabilities is mostly studied in terms of energy efficiency; maximum speed; maximum linear accelerations; cooling capacity of brake systems; resistance and deformation of elements exposed to aerodynamic forces; stability during lateral wind and during braking for straight ahead maneuvers; noise caused by airflow; proper evacuation of exhaust gases and aesthetics of cars. Generally, a model for CFD analysis is used and six constant coefficients are determined. However, there is insufficient information about the interaction of vehicle aerodynamics with vehicle suspension and the effects that this interaction generates on the dynamic behavior of the vehicle. In this work this interaction is studied, and there is an analysis of how vehicle aerodynamic characteristics impact on suspension behavior and how suspension characteristics could diminish or amplify aerodynamic.

Stringent automotive emissions and fuel economy regulations have been bringing challenges for the development of new engine technologies to achieve greater levels of efficiency and pollutants reduction. In this scenario the homogeneous charge pre-chamber jet ignition system (HCJI) enables lean operation due the jet combustion gases emerging from the small pre-chamber combustor as the ignition source for main chamber combustion in an internal combustion engine. The present computational work was carrying out to investigate the interaction between the pre-chamber and main chamber fluid dynamics events. This CFD research was performed and validated with a experimental data for a single cylinder of a 4-stroke indirect fuel injection engine under the motoring condition running at 4500 rpm with 50% wide open throttle condition.

The objective of this article is to present a root-cause analysis performed to support the fault trace of a heavy duty diesel engine breakdown, operating in high altitude. The process to elaborate a cause-effect diagram, also known as Ishikawa diagram is briefly described. Some factors that can influence the engine behavior and its reliability are listed in the cause-effect diagram. According to the failure mode analyzed, the selected factors are then described, and how they could interfere in the engine functioning.

Fulfill emission restrictions is the most challenging task of future engines development. In this context, improvements with regard to the spray and mixture formation in internal combustion engines are necessary. Experimental investigation and numerical simulation have been used to predict and analyze complex in cylinder processes. In this paper, a diesel spray characterization using optical diagnostics was made in order to provide input data and boundary conditions for a diesel spray computational fluid dynamics simulation (CFD), using the Eulerian-Lagrangian model. Combining the advantages of Eulerian and Lagrangian approaches, this model is able to predict continuously the whole spray evolution. The main difficulty of numerical spray simulation is the correct representation of the two characteristic spray zones: dense near the nozzle and dilute downstream.

This paper presents a thermal analysis of a sub-set drum/shoe brake lining of a braking system in a rear drum brake for a lightweight passenger vehicle with engines of up to 1,000 cc, for a future application to hybrid power trains. In academic databases, as well as free research database, it is difficult to find papers and even technical works which show the complete cycle of the design of an automotive braking system. It occurs mostly due to the confidentiality of industries and industrial parts suppliers, once the brake system is a product of high added value. In this study, transient temperature field distributions of the shoe lining were obtained by numerical simulations. Boundary conditions of the model were calculated according to a reference paper. The geometry and mechanical and thermal properties of the brake shoe lining were obtained from data provided by the manufacturer.

Some chemical characteristics and natural impurities of diesel fuel used in diesel engines may damage the operation of emission control devices as well as contribute to the formation of secondary pollutants in the atmosphere. Sulfur is one of the natural impurities of diesel fuel, which upon burning, combines with oxygen to form SO2, creating emissions that adversely affect both the environment and human health. Many countries around the world have adopted stringent diesel emission standards to drastically reduce the sulfur content in diesel fuel and thereby improve air quality. Many authors have addressed the need to regulate transportation fuel emissions from pollutants, including sulfur (S), carbon monoxide (CO), particulate matter (PM), nitrogen oxides (NOx) and hydrocarbons (HC). This paper addresses both regulated and non-regulated emissions from four types of diesel fuels, each with a different sulfur concentration.

The clutch pedal is one of the most used commands on vehicles and demands a robust project, good ergonomics and an adequate feeling. According to Shaver [3], a comfortable clutch pedal should have a load between 10 kgf and 13 kgf, but the total stroke, the maintenance of the load during the travel, peak load, etc. still has to be considered in the project. Basically the suggested curve for a comfortable clutch pedal starts with a progressive increase load until approximately ¼ of the stroke, and after a decreasing load until the pedal reaches its stroke limits. This effect can be produced through an auxiliary spring that ranges its force direction according to the position of the pedal. This article presents a methodology of modeling an auxiliary spring for clutch pedals and its installation geometry on the pedal box to achieve an adequate pedal feel. This theory is applied to semi-hydraulic and hydraulic systems clutches.

The purpose of this paper is to provide an overview about rowing clunk on RWD MT transmissions for pick-up trucks through means of sound pressure, case acceleration and torsional vibration. Intended to identify the proper synchronizer design features necessary for its prevention. This paper will introduce the rowing clunk phenomena and present the driving maneuvers executed to reproduce the noise. The process of analysis and the phenomena composition based on simulations results, noise measurements and vibration analysis. The objective is to share with Product Engineering community an approach for Rowing Clunk Noise mitigation on Pick-up Trucks.

A vehicle is a product that encloses high levels of complexity. Assessing its quality requires taking into account several variables simultaneously. Usually, this kind of analysis is made over one variable at a time, ignoring the multidimensional nature of the quality. This is even more critical when two or more vehicles are included in the analysis (e.g. for benchmarking purposes), or when the aim of the analysis is to evaluate the performance of more than one variable over time. This study presents an overview of the biplot, which is a low-dimensional representation of observations and variables, and the possibility to use it in monitoring multiple quality variables. We show a case study demonstrating that Principal Components Analysis (PCA) allows us to summarize in a two-dimensional biplot the information that would require a correlation matrix, several conventional plots and further analysis when comparing eight variables measured on two vehicles over the last four years.