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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.

Among all types of vehicle crashes, rollover is the most complex and yet least understood. During the last decades, a constant increase in the studies involving rollover crashes and injuries associated with it can be observed. Although the rollover is not the most frequent type of accident, it is of the greatest significance with respect to injury and trauma caused to the vehicle occupants. The existing standards and procedures to test rollover crashworthiness are still not suitable to computer simulation because of the huge computational effort required, and the need of faithful/overly complex representation of the aspects involved in real crashes. The objective of the present work is the development of computational models particularly adapted to simulate different standards and procedures used to evaluate the vehicles' roof strength. The models are compared with other approaches, and their advantages/disadvantages are discussed.

Even though the rollover is not the most frequent type of accident, it is of the greatest significance with respect to injury and trauma caused to the vehicle occupants. The need to reduce death incidence and serious injuries has increased the importance of computational simulations and prototype testing. This study presents finite element model to simulate rollover events and to predict possible injuries caused in the head, neck, thorax and cervical spine. Numerical models of a sport utility vehicle (SUV) are simulated including anthropomorphic dummy to represent the driver. The injury risks and traumas are verified to the driver considering belted and unbelted dummies. The computational methodology developed proved to be efficient for the evaluation of the vehicle's roof structure in rollover events.

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.

In the automotive industries, time and parts production costs are fundamental, mainly in prototyping production. The RTV (Room Temperature Vulcanized) process is an important alternative production to flexible silicone molds when you need to inject polyurethane parts. The objective is time reduction in tooling production and parts. RTV requires notable initial investments in equipments. Many times, this cost does not fit in the automotive third part company's budget. This work shows how is possible to obtain parts by RTV process with excellent quality, without high investments in equipments and without quality loss in produced parts. Lead times and tooling and parts costs are analyzed. Due to equipments low costs, this alternative is accessible not only to automotive industries but also to small and medium suppliers.

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.

Through computational dynamic simulations is possible to achieve high reliability index in the development of automotive components, thus reducing the time and component cost can generate significant levels of competitiveness and quality. This work suggests the validation of a methodology for simulation, able to predict and quantify the best design of the parking brake cable that although it is flexible, has in its structure composite elements of different mechanical properties. Known difficulty of mathematically predict nonlinear relationships deformation under forces and moments effect was first established, studies based on experimental measurements serve as input parameters for simulating the dynamic behavior of the flexible cable. With the aid of motion making use of NX9 CAD software, it was prepared the dynamic movement that the leaf spring suspension system does.

Through computational dynamic simulations is possible to achieve high reliability index in the development of automotive components, thereby enabling the reduction of cost and time of a product development with considerable gain in quality. This work suggests the validation of a methodology for simulation where is possible to improve the confidence level for design flexible components, such Heater and Cooling hoses that are under dynamic engine action, in relation to the physical model. Known the difficulty in predicting non-linear mathematical relationship deformation under effect of forces and moments, was established a study based on experimental measurements where were used as input parameters to simulate the dynamic behavior of flexible components, in this case, coolant hoses.

Nowadays the automotive market is reducing product development time and launching more technological vehicles, always focusing on having even more safety with better customer experience which generates big competitiveness and requires more accurate and faster development, the virtual simulations make it possible to meet this new reality with a high confidence level. This work comprises the validation of a methodology to analyze the design confidence level for flexibles associated with suspension kinematics. To validate the methodology, the scanned physical model was compared with the virtual simulations using the Simcenter 3D Flexible Pipe software. As inputs data for simulation, it is used geometrical, physical, and chemical information. Through the suspension kinematics study was establish possible movement situations to obtain the flexibles deformations attending to all suspension positions.

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 work presents aspects related to research and development of high-speed steels for valve seat inserts application. Five series of materials were evaluated: high speed steel M3/2 infiltrated with copper during sintering; high speed steel M3/2 with Cu3P addition; high speed steel M3/2 with Cu3P addition and further copper infiltrated during sintering; high speed steel M3/2 mixed with iron powder; high speed steel M3/2 mixed with iron powder and niobium carbide. The physical and mechanical properties of the evaluated high-speed steels are presented in terms of densification, hardness, and radial mechanical strength. These properties are compared according to the materials processing and heat treatment.

Rollover crashes are responsible for more than 20% of total passengers deaths in vehicular accidents. Every year a higher number of consumers have been critically injured in rollovers, which translates into hundreds of millions of dollars of unnecessary health care cost. Efforts to reduce the incidence of death and catastrophic injuries associated with rollover crashes have increased the importance of both, prototype testing and computational simulations. Automotive industry and individual researchers have performed numerous rollover tests using instrumented anthropomorphic test devices (ATD), with the objective of predicting possible head, neck, and cervical spine injuries. Some of these works measured accelerations, forces and moments on head, neck and cervical spines, which can cause several other injuries according to medical traumas databases.

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.

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.

The Brazilian Automotive regulations that are aimed towards the safety of drivers, passengers and pedestrians have gone through recent changes to prevent and/or minimize injury and trauma from different types of accidents. Until now, National Traffic Council (CONTRAN) Resolution n° 14/98 required vehicles to only have safety belts for an occupant restraint system, and frontal airbags were not required. Since the recent CONTRAN n° 311/09 Resolution requires mandatory frontal airbags, the occupant restraint system must be tuned due to the interaction with different components that may make up the system, like safety belts with pretensioners and seatbelt load limiting devices. The present study was developed to optimize the restraint system of a current vehicle in production, while focusing on minimizing the vehicle complexity. The optimization tool helped to develop a robust restraint system for the frontal passenger during a frontal impact [1].

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