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The effects of specific parts inside the vehicle body in a radiated immunity numerical simulation is addressed. The benefits of numerical simulations for electromagnetic compatibility analysis is well known and reported in the literature, nevertheless, the accuracy of the results depends on the mathematical models that is being considered. Numerous simulations were performed, detailing how specific parts of a vehicle can affect the electric field inside a vehicle. The commercial package ANSYS HFSS™ was used due to the extremely fast and accurate simulations since it uses the finite element method technique, which includes hybridizations with the method of moments. This allows full simulations to be performed in a few minutes with controlled convergence, allowing a more extensive investigation. Simulation results are compared with experimental data obtained from experiments performed at Instituto Nacional de Pesquisas Espaciais showing a good agreement.

Acoustics, in a broad sense, is an essential product attribute in the automotive industry, therefore, it is relevant to study and compare theoretical and numerical predictions to experimental acoustic measurements, key elements of many acoustic development processes. The numerical methods used in the industry for acoustic predictions are widely used for exhaust system optimization. However, the numerical and theoretical predictions very often differ from experimental results, due to modeling simplifications, temperature variations (which have high influence on speed of sound), manufacturing variations in prototype parts among others. This article aims to demonstrate the relevant steps for acoustics development applied in automotive exhaust systems and present a comparative study between experimental tests and computer simulations results for each process. The exhaust system chosen for this development was intended for a popular car 4-cylinder 1.0-liter engine.

In the middle of the global competition, inside the automotive sector, the perceived quality of costumers, related to the beauty and harmony of the outer skin surfaces of motor vehicles, has become one of the main determinant factors in the purchase process decision. In general, the initial perceived quality of a car is determined by an appealing design of its body, the color and gloss of its paint, and also the manufacturing and assembly accuracy of the skin panels. The appealing design makes the skin panel even more complex and hard to produce with current metal forming technologies and the results are often small distortions on the outer surfaces about tens of microns and most of the times paint does not cover such imperfections. Despite the technological advances along the years, surface quality inspection was still being performed by manual and subjective evaluation by experts.

Using current technologies, a single “entry level” vehicle has millions of electrical signals sent through dozens of modules, sensors and actuators, and those signals can be sent over the air, creating a telemetry data that can be used for several ends. One electrical device is set up to have diagnosis, in order to make maintenance feasible and support repair, plus giving improvement directions for specialists on new developments and specifications, but in several cases the diagnosis can only determine the mechanism of failure, but not the event that triggered that failure. Current evaluation method involves teardown, testing and knowledge from the involved specialized team, but this implies in recovering of failed parts, which in larger automakers with thousands of dealers/repair shops, reduces the sample for analyses when there is a systemic issue with one component.

The high level of reliability of virtual analysis for suspension system development should not be thinking only for comfort and performance purpose, considering the `growing number of failures due to the touch between components in dynamic condition. The study establishes a simple and optimized methodology, able to predict more accurately the flexible brake hose path subject to the steering motion and associates with the independent suspension course, aiming the best route in order to achieve a low cost and robust design. In turn, the flexible brake hose non-linear model invalidates the multibody study to get the best route. However, with the aid of motion making use of NX9 [1] CAD [2] software was prepared dynamic movement that subjects front independent suspension system that establishes a Cartesian routine that maps 977 points, much higher than 9 points from previous studies, comprising a more accurate path performed by the hose.

The current study has the proposal to approach the differences in dynamic behavior between camshaft manufactured in the traditional gray cast iron and an alloyed gray cast iron with the improvement on mechanical properties in order to stresses found on roller finger follower applied systems. The main objective of this paper is to show that camshaft made of modified gray cast iron and heat treated through the remelting process is still a good solution for application with roller finger followers systems which requires higher wear resistance standards. The proposed experimental study consists of comparative analysis of microstructure and hardness, dynamometers tests, dimensional measurements of camshafts, and after that, intends to show the higher performance of this manufacturing process in more severe applications of internal combustion engines.

Carbon canisters are used in gasoline passenger vehicle and light duty truck applications. The component is part of the vehicle emission control system. Activated carbon (also known as charcoal) traps hydrocarbon vapors from the fuel tank and vapors created during the fuel tank refueling and venting events. Canister design, charcoal type and performance have been driven by evaporative emission regulations around the world, and evaporative emission requirements have enhanced through the years. The trend of evaporative emission requirements in Brazil indicates the use of improved carbon canisters in the near future. Carbon canisters are needed to store hydrocarbons that would otherwise pollute the environment. Wood based activated carbon is manufactured from sawdust, which is a renewable resource. The result is a healthier earth on which we live. Figure 1 illustrates the activation process of carbon. Figure 1 Activation process of carbon.

The purpose of this study is to establish the criteria of election of an electrical architecture tailor-made for the emerging markets, to be applied during the whole vehicle's lifecycle. A literature review about related subjects as the meaning of "electrical architecture," its techniques, criteria and methodologies of development, and the definitions of emerging and developed markets is also presented. Based on the bibliographical research, documentary analysis and unstructured interviews with active members of the automotive industry, the criteria for election of electrical architectures for emerging markets was established, as well as their describers and swing-weights, required by the use of the additive aggregation method - a multi-criteria decision taking method. The criteria were applied in two case studies of automotive industry: the developments of a low-cost hatch vehicle and a mid-size luxury sedan vehicle, both designed for emerging markets.

Nowadays, electromagnetic compatibility (EMC) has taken an important role in automotive development. This is because the effects that EMC can cause in a vehicle or on the environment. All systems contained in a vehicle emit EMC, and can be influenced by it also. During the vehicle design phase some variables have to be considered and improved to make the vehicle to be electromagnetic compatible. We can list the vehicle systems as electromagnetic generators or victims, as below: Generators: Ignition GPS transmission system Mobile phone transmission system Electrical motors Radars Power modules Victims: Sensors Cables Control modules (BCM, ECM, etc.) An example of a complete system subject to the EM effects is the X-by-wire (or drive-by-wire) system, where mechanical systems are substituted by modules, cables, sensors, actuators. This system has to be designed considering electromagnetic compatibility.

The growing need to avoid failures in vehicle components have become the methods of quality control of manufacturing processes more efficient and accurate, especially in safety components like automotive wheels. The aim of this work is examines the efficiency of aluminum-silicon specifications related to wheel quality for avoiding the poor results obtained in impact and fatigue tests as result of improper settings in the chemical composition and manufacture process. It is evaluated mainly the content of magnesium in aluminum alloys and certified the correct degree of silicon modification in the microstructure on the performance of these wheels. The test results indicate that even with the chemical composition parameters specified by the standard, the technical validation of the product may not be adequate.

The current study proposes to approach the fatigue behavior of stabilizer bars and specimens manufactured in quenched / tempered and as-received SAE5160 steels with and without a surface micro-notch. Some S-N specimens and stabilizer bars were shot-peened to improve the fatigue strength due to creation of compressive surface residue stresses and by surface plastic strain and others samples received a surface micro-notch of 0.3 mm depth introduced by EDM process. The crack growth evaluation at micro-notch was made comparatively with da/dN-ΔK curves in CT specimens. The proposed experimental study consists of comparative analysis of da/dN-ΔK and S-N curves, fractographic and, metallographic analysis, stabilizer bar bench tests, and after that, it is intended to show the relevant aspects of two microstructural classes currently specified for stabilizer bars, the beneficial effects obtained by shot peening and the bad influences of surface micro-notches.

In order to illustrate the constant development of the automatic transmission controls area, this paper describes how the garage shift calibration works in vehicles with transverse front wheel drive powertrains. A garage shift (GS) is the turbine speed transient commanded by the shift lever movement from Park to Drive or Reverse, from Neutral to Drive or Reverse, from Drive to Reverse, from Reverse to Drive, or from Drive or Reverse to Neutral [1]. A usual metric to verify the garage shift comfort is the data acquisition of the fore-aft acceleration on the seat track, but also the shift time should be considered, as well as the clutch energy and the repeatability of the shift feeling for different temperatures and engine idle speed levels. This paper demonstrates the transmission calibration strategies to determine a sensitive and a non-sensitive garage shift and its interactions with the engine calibration.

The application of press hardening steels (PHS) Al-Si coating has been increasing in body in white vehicles as an approach to meet the demands of safety and CO2 reduction regulations. The vehicle structures with PHS largely depend on the integrity and the mechanical performance of the spots weld. During the spot welding process, intermetallic phase may appear in function of the chemical composition of the steel and coating. One of these intermetallics is the Fe-Al phase which brittleness decreases the strength of the weld joint. In this study, resistance spot welding (RSW) experiments were performed in order to evaluate the influence of the welding parameters of single-lap joints PHS - 22MnB5 steel grade.

Drive a vehicle through corners is a very complex activity, since it means change of movement states. Considering a typical corner, the driver starts in a transient state, changes to a steady state and again changes to transient. Those variations make the vehicle change its behavior due specific suspension and steering characteristics. The idea of this paper is show how only one of those characteristics, the understeer gradient, have influence in the stability perception of the driver. The focus is show how the understeer gradient variation can induce perception of low stability in vehicle when cornering no matter the vehicle still keeps its correct path. This variation means an understeer gradient “acceleration”, the metric human being can perceive, in other words the feeling of stability or its lack of.

The current study shows important results obtained by a new technique of residual stress virtual evaluation in automotive components for improving the development and quality of new products, aiming the structural performance, mass and cost reductions. The approaching those virtual results were adjusted by metallurgic data obtained in metallography, mechanical and chemical analysis. As part of this proposal, an automotive aluminum wheel belong to current production was evaluated in accordance with data acquired in the wheel manufacturing process. It was taking in account the real information of casting process parameters and the metallurgic information obtained in laboratorial tests. In this work, the results show that product residual stresses shall be considerate and evaluated during design phases as improving proposal, new technical concerns and quality improving.

This Paper presents the “Frequency Sweep Virtual Analysis” as a tool to help to define the best powertrain mount concept in order to identify the resonance mode frequency on Powertrain System. Applying this method, we can identify proposals to reduce loads in the Powertrain system due the resonance mode and consequently minimize possibility of exceeding material strength. The “Frequency Sweep Virtual Analysis” drives the powertrain mounts design to avoid running many Road Load Data Acquisitions (RLDA) in a trial-and-error process (Cost reduction and timing savings).

The development of fuel systems components are becoming challenging with the increasing use of Biofuels like Biodiesels and Ethanol around the world. Biodiesels are one of the most challenging fuels, once they can have multiple sources, which influences its characteristics, mainly the oxidization stability and peroxide levels. As the fuel characteristics changes along the time, the correct materials selection during the development phase is very important for the fuel system performance during the vehicle lifetime. One of the components most affected by the Biodiesel is the in tank fuel pump system. During the vehicle lifetime, it is exposed to all sorts of fuel and its contaminants and exposed to system stress factors like temperature and voltage variation. The wires insulation in the fuel pump systems are one of the most affected components.

This paper proposes a methodology for automotive manufacturing lines scheduling. This methodology is based on generalized stochastic Petri Nets and Markov decision processes with imprecise probabilities. The usual generalized stochastic Petri Nets is extended by allowing imprecision about probabilities to be explicitly represented and by human task time graph of different products to be attached. Once the system is modeled using this tool and its extensions, we translate the resulting models into Markov decision processes with imprecise probabilities, in order to compute optimal policies that will result in the line scheduling. This paper introduces an algorithm that performs this translation.

The present work gives an overview of the current situation of failures that may occur in automotive components, showing their distribution in the vehicle and the causes that make them occur, trying to emphasize the different materials which are used in the manufacturing of these components. This work is a technical approach strictly supported by an engineering concept which aims to discuss the different factors which contribute to cause premature failures of automotive components, prior to their utilization in the field or when they are exposed to the most variable conditions of use. One of the most important objectives of this study is to call the attention of design engineers, research engineers and manufacturing people to the importance of the components integrity which shall be taken into primary consideration in the design phase as well as in the specification of the material and process of manufacturing.

The purpose of the theme developed in this work is to increase the volume of information related to vehicle evaluation and how human perception can be translated into numbers, thus facilitating the process of definitions, refinement and analysis of its performance. Based on the discipline of psychophysics, where it is possible to study the relationship between stimulus and sensation and the use of post processing tool known as PSD (Power Spectral Density), post process the acceleration data of inputs perceived by the occupants of the vehicle, when driving in routes considered ergodic. By this, in a summarized way, get to human subjective perception of comfort. This material shows in a conceptual way a sequence of studies that were conducted to make it possible, to generate a performance classification of the subjective vehicle attribute of Smoothness, by processing values of acceleration measured the driver's seat.