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This paper makes an analysis of problems encountered in assembling components from automotive vehicles. It shows wheel and tires assembling cases of an automaker that applies lean manufacturing concepts in the production process. This study not only makes the analysis from the best way to apply the methodology to seek for the root cause, but also uses methodology to identify containment measures, defining robust solutions capable of preventing the incidence of similar problems. This methodology can be applied to solving problems of any production process, even outside of the automotive industry

The current study shows interesting results obtained by a new virtual approaching for evaluating the final stresses presented in automotive components during its application in vehicle which suggests product engineers a new tool for measuring the residual stresses in casting. As part of this proposal, an automotive as-cast aluminum wheel belong to current production was evaluated in accordance with data acquired in its manufacturing process. At that step, it was taking into account the real information of casting process parameters and the metallurgic results obtained in laboratorial tests such as, metallographic, chemical and mechanical tests. FEA (Finite Element Analysis) on simulation of wheel loading stress was made regarding those preliminary data obtained in CRSFEA simulation (cast residual stress finite element analysis) as entered parameters.

It is known acoustic comfort is a key feature to meet customer expectations for many products. In the current automotive industry, vehicle interior quietness is seen as one of the most important product attributes regarding perceived quality. A quiet interior can be achieved through an appropriate balance of noise sources levels and acoustic materials. However, the choice of the most efficient acoustic content may be challenging under severe cost and mass restraints commonly found in emerging market vehicles. Therefore, it is fundamental to develop efficient materials which will provide high acoustic performance with lower weight and cost. In this paper the fine tuning of the headliner structure is presented as an efficient way to increase acoustic performance. Structures currently employed for this vehicle subsystem are described. Airflow resistance and sound absorption measurements are used to guide development and make precise manufacturing process changes.

The definition of the ride attribute is very difficult because it is part of human perception during driving. For vehicle dynamics work, have details of what is good or what is bad considering driving comfort, usually, induces some controversial opinions. In this work, the use of a single accelerometer is shown as a tool to characterize the basic vehicle vibrational behavior and so support the correlation between human perception and the resulting ride comfort presented. By using PSD theory, it is possible to “see” how the vehicle vibrates and so have a better understanding of where in the vehicle is located a possible issue and how to fix it. In a more advanced point of view is possible to characterize each vehicle with a ride “personality”, this meaning how each brand and model behave and so how vehicle behave to the consumer approve or complain about it..

This paper explores the method of modeling and validation the computational tools able to accurately replicate the dynamic behavior of a Formula SAE vehicle. Based on limitations in conducting physical tests, it is possible to mathematically predict the forces and momentum generated on the steering column of the vehicle, minimizing effort and improving driver comfort even before the component physically manufactured. The results in permanent state due technical instrumentations were used in the physical vehicles and compared with other proposals (skid Pad test). As the software simulating the same path, it was possible to adopt values of speed and wheel steering, allowing compare the dynamics of the vehicle, through the signals from other sensors installed in the data acquisition system, validating the behavior of the models presented in permanent state. Other aspects were studied to understand vehicle behavior concerning lateral stability and steering behavior.

According to several customer perception survey, Squeak and Rattle (S&R) is among the top most annoying defects. Consequently, GMB engineering design, development and validation process must be continuously improved and consistently applied to all platforms to guarantee that all products are free from squeaks and rattles. This paper introduces those concepts and discusses some strategies to eliminate or minimize S&R. Concepts and tests results are commented. Finally, the challenge in detection and analysis of S&R is discussed. Objective and subjective evaluation methodologies are being developed and suppliers training and integration have been improved

The globalization, rivalry and the technologies have changed the auto industry in a battlefield, where companies are fighting for quality, reliability, the reduction of development cycle and also cost. The manufacturing process of car body is the major responsible for time consumption, labor and investment. One of the bottleneck solutions is to use computational simulations during design phase in order to minimize the reworks. The car body is composed by several stamped parts, and its design requires a series of parallel activities, and one of the fundamental information is the accurate magnitude of spring back distortions, but due to the complexity of the phenomenon, the results are not so accurate as desired. The explored literatures are recommending numeric methods to simulate material's behavior and also the spring back phenomenon.

Since the globalization, the automotive competition is growing every day, and automotive products (vehicles and components) are often developed in one country though it's made, used and applied in other markets. The operating conditions such as height, climate, topography, customer perception and other variables are often different from one market to another and could influence on the products reliability. If the market operating conditions are not considered in the vehicle development phase, the product may not fully perform its intended function over useful life period, and also may experience an excessive level of field complaints and/or failure modes specific to those markets and also damage the image of the brand.

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.

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 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.

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.

Reliability, maintainability/serviceability and security are three qualities of product excellence desired by customers and users of products, however customer expectation for product reliability are continually increasing for almost all product and despite of most of the companies has worked on the philosophy of continuous improvement to meet or exceed the customer's expectations, its difficult to avoid failures or its difficult to ensure zero defect. Once it happens, it generate a customer complaint which is registered by companies. The way that companies used to register the complaints is through their warranty system and also a special database. Most of the companies maintain warranty databases for purposes of financial reporting and warranty expense forecasting. In some cases, there are attempts to extract engineering information from such databases. Another application is to use warranty data to detect potentially serious field reliability problems as early as possible.

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.

Vehicular manual transmissions systems often use a vent or breather to allow pressure control inside the main structure. This pressure variation comes along with differences caused by working temperature range. However along with air flow these vents may occasionally allow oil passage noticed by vehicle owner as a transmission leakage event. The more sophisticated the more expensive is the venting device which may contain membranes, labyrinths, baffles and other solutions to avoid leakage. The purpose of this paper is to present a simplified solution to avoid transmission fluid leakage by combining a regular sealing device (fiber concept gasket) and a baffle to avoid oil splash to reach the venting device. The proposed concept took into consideration a quick implementation aspect, low financial impact and less complexity to the overall current system modifying an existing component by adding secondary function instead of creating additional components.

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.

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.

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.

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.